WorldWideScience

Sample records for bird migration flight

  1. Circadian flight schedules in night-migrating birds caught on migration.

    Science.gov (United States)

    Coppack, Timothy; Becker, Simon F; Becker, Philipp J J

    2008-12-23

    Many species of migratory birds migrate in a series of solitary nocturnal flights. Between flights, they stop to rest and refuel for the next segment of their journey. The mechanism controlling this behaviour has long remained elusive. Here, we show that wild-caught migratory redstarts (Phoenicurus phoenicurus) are consistent in their flight scheduling. An advanced videographic system enabled us to determine the precise timing of flight activity in redstarts caught at a northern European stopover site during their return trip from Africa. Birds were held captive for three days in the absence of photoperiodic cues (constant dim light) and under permanent food availability. Despite the absence of external temporal cues, birds showed clear bimodal activity patterns: intense nocturnal activity alternating with diurnal foraging and resting periods. The onset of their migratory activity coincided with the time of local sunset and was individually consistent on consecutive nights. The data demonstrate that night-migrating birds are driven by autonomous circadian clocks entrained by sunset cues. This timekeeping system is probably the key factor in the overall control of nocturnal songbird migration.

  2. Palaearctic-African Bird Migration

    DEFF Research Database (Denmark)

    Iwajomo, Soladoye Babatola

    Bird migration has attracted a lot of interests over past centuries and the methods used for studying this phenomenon has greatly improved in terms of availability, dimension, scale and precision. In spite of the advancements, relatively more is known about the spring migration of trans-Saharan m......Bird migration has attracted a lot of interests over past centuries and the methods used for studying this phenomenon has greatly improved in terms of availability, dimension, scale and precision. In spite of the advancements, relatively more is known about the spring migration of trans...... of birds from Europe to Africa and opens up the possibility of studying intra-African migration. I have used long-term, standardized autumn ringing data from southeast Sweden to investigate patterns in biometrics, phenology and population trends as inferred from annual trapping totals. In addition, I...... in the population of the species. The papers show that adult and juvenile birds can use different migration strategies depending on time of season and prevailing conditions. Also, the fuel loads of some individuals were theoretically sufficient for a direct flight to important goal area, but whether they do so...

  3. Avian Alert - a bird migration early warning system

    NARCIS (Netherlands)

    van Gasteren, H.; Shamoun-Baranes, J.; Ginati, A.; Garofalo, G.

    2008-01-01

    Every year billions of birds migrate from breeding areas to their wintering ranges, some travelling over 10,000 km. Stakeholders interested in aviation flight safety, spread of disease, conservation, education, urban planning, meteorology, wind turbines and bird migration ecology are interested in

  4. Comparing aerodynamic efficiency in birds and bats suggests better flight performance in birds.

    Directory of Open Access Journals (Sweden)

    Florian T Muijres

    Full Text Available Flight is one of the energetically most costly activities in the animal kingdom, suggesting that natural selection should work to optimize flight performance. The similar size and flight speed of birds and bats may therefore suggest convergent aerodynamic performance; alternatively, flight performance could be restricted by phylogenetic constraints. We test which of these scenarios fit to two measures of aerodynamic flight efficiency in two passerine bird species and two New World leaf-nosed bat species. Using time-resolved particle image velocimetry measurements of the wake of the animals flying in a wind tunnel, we derived the span efficiency, a metric for the efficiency of generating lift, and the lift-to-drag ratio, a metric for mechanical energetic flight efficiency. We show that the birds significantly outperform the bats in both metrics, which we ascribe to variation in aerodynamic function of body and wing upstroke: Bird bodies generated relatively more lift than bat bodies, resulting in a more uniform spanwise lift distribution and higher span efficiency. A likely explanation would be that the bat ears and nose leaf, associated with echolocation, disturb the flow over the body. During the upstroke, the birds retract their wings to make them aerodynamically inactive, while the membranous bat wings generate thrust and negative lift. Despite the differences in performance, the wake morphology of both birds and bats resemble the optimal wake for their respective lift-to-drag ratio regimes. This suggests that evolution has optimized performance relative to the respective conditions of birds and bats, but that maximum performance is possibly limited by phylogenetic constraints. Although ecological differences between birds and bats are subjected to many conspiring variables, the different aerodynamic flight efficiency for the bird and bat species studied here may help explain why birds typically fly faster, migrate more frequently and migrate

  5. Comparing aerodynamic efficiency in birds and bats suggests better flight performance in birds.

    Science.gov (United States)

    Muijres, Florian T; Johansson, L Christoffer; Bowlin, Melissa S; Winter, York; Hedenström, Anders

    2012-01-01

    Flight is one of the energetically most costly activities in the animal kingdom, suggesting that natural selection should work to optimize flight performance. The similar size and flight speed of birds and bats may therefore suggest convergent aerodynamic performance; alternatively, flight performance could be restricted by phylogenetic constraints. We test which of these scenarios fit to two measures of aerodynamic flight efficiency in two passerine bird species and two New World leaf-nosed bat species. Using time-resolved particle image velocimetry measurements of the wake of the animals flying in a wind tunnel, we derived the span efficiency, a metric for the efficiency of generating lift, and the lift-to-drag ratio, a metric for mechanical energetic flight efficiency. We show that the birds significantly outperform the bats in both metrics, which we ascribe to variation in aerodynamic function of body and wing upstroke: Bird bodies generated relatively more lift than bat bodies, resulting in a more uniform spanwise lift distribution and higher span efficiency. A likely explanation would be that the bat ears and nose leaf, associated with echolocation, disturb the flow over the body. During the upstroke, the birds retract their wings to make them aerodynamically inactive, while the membranous bat wings generate thrust and negative lift. Despite the differences in performance, the wake morphology of both birds and bats resemble the optimal wake for their respective lift-to-drag ratio regimes. This suggests that evolution has optimized performance relative to the respective conditions of birds and bats, but that maximum performance is possibly limited by phylogenetic constraints. Although ecological differences between birds and bats are subjected to many conspiring variables, the different aerodynamic flight efficiency for the bird and bat species studied here may help explain why birds typically fly faster, migrate more frequently and migrate longer distances

  6. Avian Alert - a bird migration early warning system

    OpenAIRE

    van Gasteren, H.; Shamoun-Baranes, J.; Ginati, A.; Garofalo, G.

    2008-01-01

    Every year billions of birds migrate from breeding areas to their wintering ranges, some travelling over 10,000 km. Stakeholders interested in aviation flight safety, spread of disease, conservation, education, urban planning, meteorology, wind turbines and bird migration ecology are interested in information on bird movements. Collecting and disseminating useful information about such mobile creatures exhibiting diverse behaviour is no simple task. However, ESA’s Integrated Application Promo...

  7. The Flight of Birds and Other Animals

    Directory of Open Access Journals (Sweden)

    Colin J. Pennycuick

    2015-09-01

    Full Text Available Methods of observing birds in flight now include training them to fly under known conditions in wind tunnels, and fitting free-flying birds with data loggers, that are either retrieved or read remotely via satellite links. The performance that comes to light depends on the known limitations of the materials from which they are made, and the conditions in which the birds live. Bird glide polars can be obtained by training birds to glide in a tilting wind tunnel. Translating these curves to power required from the flight muscles in level flight requires drag coefficients to be measured, which unfortunately does not work with bird bodies, because the flow is always fully detached. The drag of bodies in level flight can be determined by observing wingbeat frequency, and shows CD values around 0.08 in small birds, down to 0.06 in small waders specialised for efficient migration. Lift coefficients are up to 1.6 in gliding, or 1.8 for short, temporary glides. In-flight measurements can be used to calculate power curves for birds in level flight, and this has been applied to migrating geese in detail. These typically achieve lift:drag ratios around 15, including allowances for stops, as against 19 for continuous powered flight. The same calculations, applied to Pacific Black-tailed Godwits which start with fat fractions up to 0.55 at departure, show that such birds not only cross the Pacific to New Zealand, but have enough fuel in hand to reach the South Pole if that were necessary. This performance depends on the “dual fuel” arrangements of these migrants, whereby they use fat as their main fuel, and supplement this by extra fuel from burning the engine (flight muscles, as less power is needed later in the flight. The accuracy of these power curves has never been checked, although provision for stopping the bird, and making these checks at regular intervals during a simulated flight was built into the original design of the Lund wind tunnel. The

  8. Atmospheric conditions create freeways, detours and tailbacks for migrating birds.

    Science.gov (United States)

    Shamoun-Baranes, Judy; Liechti, Felix; Vansteelant, Wouter M G

    2017-07-01

    The extraordinary adaptations of birds to contend with atmospheric conditions during their migratory flights have captivated ecologists for decades. During the 21st century technological advances have sparked a revival of research into the influence of weather on migrating birds. Using biologging technology, flight behaviour is measured across entire flyways, weather radar networks quantify large-scale migratory fluxes, citizen scientists gather observations of migrant birds and mechanistic models are used to simulate migration in dynamic aerial environments. In this review, we first introduce the most relevant microscale, mesoscale and synoptic scale atmospheric phenomena from the point of view of a migrating bird. We then provide an overview of the individual responses of migrant birds (when, where and how to fly) in relation to these phenomena. We explore the cumulative impact of individual responses to weather during migration, and the consequences thereof for populations and migratory systems. In general, individual birds seem to have a much more flexible response to weather than previously thought, but we also note similarities in migratory behaviour across taxa. We propose various avenues for future research through which we expect to derive more fundamental insights into the influence of weather on the evolution of migratory behaviour and the life-history, population dynamics and species distributions of migrant birds.

  9. Thermal impact of migrating birds' wing color on their flight performance: Possibility of new generation of biologically inspired drones.

    Science.gov (United States)

    Hassanalian, M; Abdelmoula, H; Ben Ayed, S; Abdelkefi, A

    2017-05-01

    The thermal impact of the birds' color on their flight performance are investigated. In most of the large migrating birds, the top of their wings is black. Considering this natural phenomenon in the migrating birds, such as albatross, a thermal analysis of the boundary layer of their wings is performed during the year depending on the solar insulation. It is shown that the temperature difference between the bright and dark colored top wing surface is around 10°C. The dark color on the top of the wing increases the temperature of the boundary layer over the wing which consequently reduces the skin drag force over the wing. This reduction in the drag force can be considered as one of the effective factors for long endurance of these migrating birds. This research should lead to improved designs of the drones by applying the inspired colors which can help drones increase their endurance. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Bird or bat: comparing airframe design and flight performance

    International Nuclear Information System (INIS)

    Hedenstroem, Anders; Johansson, L Christoffer; Spedding, Geoffrey R

    2009-01-01

    Birds and bats have evolved powered flight independently, which makes a comparison of evolutionary 'design' solutions potentially interesting. In this paper we highlight similarities and differences with respect to flight characteristics, including morphology, flight kinematics, aerodynamics, energetics and flight performance. Birds' size range is 0.002-15 kg and bats' size range is 0.002-1.5 kg. The wingbeat kinematics differ between birds and bats, which is mainly due to the different flexing of the wing during the upstroke and constraints by having a wing of feathers and a skin membrane, respectively. Aerodynamically, bats appear to generate a more complex wake than birds. Bats may be more closely adapted for slow maneuvering flight than birds, as required by their aerial hawking foraging habits. The metabolic rate and power required to fly are similar among birds and bats. Both groups share many characteristics associated with flight, such as for example low amounts of DNA in cells, the ability to accumulate fat as fuel for hibernation and migration, and parallel habitat-related wing shape adaptations

  11. Methods of quantitative and qualitative analysis of bird migration with a tracking radar

    Science.gov (United States)

    Bruderer, B.; Steidinger, P.

    1972-01-01

    Methods of analyzing bird migration by using tracking radar are discussed. The procedure for assessing the rate of bird passage is described. Three topics are presented concerning the grouping of nocturnal migrants, the velocity of migratory flight, and identification of species by radar echoes. The height and volume of migration under different weather conditions are examined. The methods for studying the directions of migration and the correlation between winds and the height and direction of migrating birds are presented.

  12. Light pollution is greatest within migration passage areas for nocturnally-migrating birds around the world.

    Science.gov (United States)

    Cabrera-Cruz, Sergio A; Smolinsky, Jaclyn A; Buler, Jeffrey J

    2018-02-19

    Excessive or misdirected artificial light at night (ALAN) produces light pollution that influences several aspects of the biology and ecology of birds, including disruption of circadian rhythms and disorientation during flight. Many migrating birds traverse large expanses of land twice every year at night when ALAN illuminates the sky. Considering the extensive and increasing encroachment of light pollution around the world, we evaluated the association of the annual mean ALAN intensity over land within the geographic ranges of 298 nocturnally migrating bird species with five factors: phase of annual cycle, mean distance between breeding and non-breeding ranges, range size, global hemisphere of range, and IUCN category of conservation concern. Light pollution within geographic ranges was relatively greater during the migration season, for shorter-distance migrants, for species with smaller ranges, and for species in the western hemisphere. Our results suggest that migratory birds may be subject to the effects of light pollution particularly during migration, the most critical stage in their annual cycle. We hope these results will spur further research on how light pollution affects not only migrating birds, but also other highly mobile animals throughout their annual cycle.

  13. Obese super athletes: fat-fueled migration in birds and bats.

    Science.gov (United States)

    Guglielmo, Christopher G

    2018-03-07

    Migratory birds are physiologically specialized to accumulate massive fat stores (up to 50-60% of body mass), and to transport and oxidize fatty acids at very high rates to sustain flight for many hours or days. Target gene, protein and enzyme analyses and recent -omic studies of bird flight muscles confirm that high capacities for fatty acid uptake, cytosolic transport, and oxidation are consistent features that make fat-fueled migration possible. Augmented circulatory transport by lipoproteins is suggested by field data but has not been experimentally verified. Migratory bats have high aerobic capacity and fatty acid oxidation potential; however, endurance flight fueled by adipose-stored fat has not been demonstrated. Patterns of fattening and expression of muscle fatty acid transporters are inconsistent, and bats may partially fuel migratory flight with ingested nutrients. Changes in energy intake, digestive capacity, liver lipid metabolism and body temperature regulation may contribute to migratory fattening. Although control of appetite is similar in birds and mammals, neuroendocrine mechanisms regulating seasonal changes in fuel store set-points in migrants remain poorly understood. Triacylglycerol of birds and bats contains mostly 16 and 18 carbon fatty acids with variable amounts of 18:2n-6 and 18:3n-3 depending on diet. Unsaturation of fat converges near 70% during migration, and unsaturated fatty acids are preferentially mobilized and oxidized, making them good fuel. Twenty and 22 carbon n-3 and n-6 polyunsaturated fatty acids (PUFA) may affect membrane function and peroxisome proliferator-activated receptor signaling. However, evidence for dietary PUFA as doping agents in migratory birds is equivocal and requires further study. © 2018. Published by The Company of Biologists Ltd.

  14. The role of the antioxidant system during intense endurance exercise: lessons from migrating birds.

    Science.gov (United States)

    Cooper-Mullin, Clara; McWilliams, Scott R

    2016-12-01

    During migration, birds substantially increase their metabolic rate and burn fats as fuel and yet somehow avoid succumbing to overwhelming oxidative damage. The physiological means by which vertebrates such as migrating birds can counteract an increased production of reactive species (RS) are rather limited: they can upregulate their endogenous antioxidant system and/or consume dietary antioxidants (prophylactically or therapeutically). Thus, birds can alter different components of their antioxidant system to respond to the demands of long-duration flights, but much remains to be discovered about the complexities of RS production and antioxidant protection throughout migration. Here, we use bird migration as an example to discuss how RS are produced during endurance exercise and how the complex antioxidant system can protect against cellular damage caused by RS. Understanding how a bird's antioxidant system responds during migration can lend insights into how antioxidants protect birds during other life-history stages when metabolic rate may be high, and how antioxidants protect other vertebrates from oxidative damage during endurance exercise. © 2016. Published by The Company of Biologists Ltd.

  15. Stop early to travel fast: modelling risk-averse scheduling among nocturnally migrating birds

    NARCIS (Netherlands)

    McLaren, J.D.; Shamoun-Baranes, J.; Bouten, W.

    2013-01-01

    Many migrating birds divide their journeys into nocturnal flights interspersed by stopovers where they build up energy reserves (fuel) for subsequent flights. Given the difficulty in monitoring fuel loads of individual migrants over long distances, theoretical models are often used to interpret

  16. Aerodynamics of bird flight

    Directory of Open Access Journals (Sweden)

    Dvořák Rudolf

    2016-01-01

    Full Text Available Unlike airplanes birds must have either flapping or oscillating wings (the hummingbird. Only such wings can produce both lift and thrust – two sine qua non attributes of flying.The bird wings have several possibilities how to obtain the same functions as airplane wings. All are realized by the system of flight feathers. Birds have also the capabilities of adjusting the shape of the wing according to what the immediate flight situation demands, as well as of responding almost immediately to conditions the flow environment dictates, such as wind gusts, object avoidance, target tracking, etc. In bird aerodynamics also the tail plays an important role. To fly, wings impart downward momentum to the surrounding air and obtain lift by reaction. How this is achieved under various flight situations (cruise flight, hovering, landing, etc., and what the role is of the wing-generated vortices in producing lift and thrust is discussed.The issue of studying bird flight experimentally from in vivo or in vitro experiments is also briefly discussed.

  17. Bird migration patterns in the arid southwest-Final report

    Science.gov (United States)

    Ruth, Janet M.; Felix, Rodney K.; Dieh, Robert H.

    2010-01-01

    To ensure full life-cycle conservation, we need to understand migrant behavior en route and how migrating species use stopover and migration aerohabitats. In the Southwest, birds traverse arid and mountainous landscapes in migration. Migrants are known to use riparian stopover habitats; we know less about how migrant density varies across the Southwest seasonally and annually, and how migrants use other habitat types during migratory stopover. Furthermore, we lack information about migrant flight altitudes, speeds, and directions of travel, and how these patterns vary seasonally and annually across the Southwest. Using weather surveillance radar data, we identified targets likely dominated by nocturnally migrating birds and determined their flight altitudes, speeds, directions over ground, and variations in abundance. Migrating or foraging bats likely are present across the region in some of these data, particularly in central Texas. We found that migrants flew at significantly lower altitudes and significantly higher speeds in spring than in fall. In all seasons migrants maintained seasonally appropriate directions of movement. We detected significant differences in vertical structure of migrant densities that varied both geographically within seasons and seasonally within sites. We also found that in fall there was a greater and more variable passage of migrants through the central part of the borderlands (New Mexico and west Texas); in spring there was some suggestion of greater and more variable passage of migrants in the eastern borderlands (central and south Texas). Such patterns are consistent with the existence of at least two migration systems through western North America and the use of different migration routes in spring and fall for at least some species. Using radar data and satellite land cover data, we determined the habitats with which migrants are associated during migration stopover. There were significant differences in bird densities among

  18. Green Light for Nocturnally Migrating Birds

    Directory of Open Access Journals (Sweden)

    Hanneke Poot

    2008-12-01

    Laboratory experiments have shown the magnetic compass to be wavelength dependent: migratory birds require light from the blue-green part of the spectrum for magnetic compass orientation, whereas red light (visible long-wavelength disrupts magnetic orientation. We designed a field study to test if and how changing light color influenced migrating birds under field conditions. We found that nocturnally migrating birds were disoriented and attracted by red and white light (containing visible long-wavelength radiation, whereas they were clearly less disoriented by blue and green light (containing less or no visible long-wavelength radiation. This was especially the case on overcast nights. Our results clearly open perspective for the development of bird-friendly artificial lighting by manipulating wavelength characteristics. Preliminary results with an experimentally developed bird-friendly light source on an offshore platform are promising. What needs to be investigated is the impact of bird-friendly light on other organisms than birds.

  19. Modeling Bird Migration under Climate Change: A Mechanistic Approach

    Science.gov (United States)

    Smith, James A.

    2009-01-01

    How will migrating birds respond to changes in the environment under climate change? What are the implications for migratory success under the various accelerated climate change scenarios as forecast by the Intergovernmental Panel on Climate Change? How will reductions or increased variability in the number or quality of wetland stop-over sites affect migratory bird species? The answers to these questions have important ramifications for conservation biology and wildlife management. Here, we describe the use of continental scale simulation modeling to explore how spatio-temporal changes along migratory flyways affect en-route migration success. We use an individually based, biophysical, mechanistic, bird migration model to simulate the movement of shorebirds in North America as a tool to study how such factors as drought and wetland loss may impact migratory success and modify migration patterns. Our model is driven by remote sensing and climate data and incorporates important landscape variables. The energy budget components of the model include resting, foraging, and flight, but presently predation is ignored. Results/Conclusions We illustrate our model by studying the spring migration of sandpipers through the Great Plains to their Arctic breeding grounds. Why many species of shorebirds have shown significant declines remains a puzzle. Shorebirds are sensitive to stop-over quality and spacing because of their need for frequent refueling stops and their opportunistic feeding patterns. We predict bird "hydrographs that is, stop-over frequency with latitude, that are in agreement with the literature. Mean stop-over durations predicted from our model for nominal cases also are consistent with the limited, but available data. For the shorebird species simulated, our model predicts that shorebirds exhibit significant plasticity and are able to shift their migration patterns in response to changing drought conditions. However, the question remains as to whether this

  20. Efficient Parallel Sorting for Migrating Birds Optimization When Solving Machine-Part Cell Formation Problems

    Directory of Open Access Journals (Sweden)

    Ricardo Soto

    2016-01-01

    Full Text Available The Machine-Part Cell Formation Problem (MPCFP is a NP-Hard optimization problem that consists in grouping machines and parts in a set of cells, so that each cell can operate independently and the intercell movements are minimized. This problem has largely been tackled in the literature by using different techniques ranging from classic methods such as linear programming to more modern nature-inspired metaheuristics. In this paper, we present an efficient parallel version of the Migrating Birds Optimization metaheuristic for solving the MPCFP. Migrating Birds Optimization is a population metaheuristic based on the V-Flight formation of the migrating birds, which is proven to be an effective formation in energy saving. This approach is enhanced by the smart incorporation of parallel procedures that notably improve performance of the several sorting processes performed by the metaheuristic. We perform computational experiments on 1080 benchmarks resulting from the combination of 90 well-known MPCFP instances with 12 sorting configurations with and without threads. We illustrate promising results where the proposal is able to reach the global optimum in all instances, while the solving time with respect to a nonparallel approach is notably reduced.

  1. The function of migratory bird calls

    DEFF Research Database (Denmark)

    Reichl, Thomas; Andersen, Bent Bach; Larsen, Ole Næsbye

    The function of migratory bird calls: do they influence orientation and navigation?   Thomas Reichl1, Bent Bach Andersen2, Ole Naesbye Larsen2, Henrik Mouritsen1   1Institute of Biology, University of Oldenburg, Oldenburg, D-26111 Oldenburg, Germany 2Institute of Biology, University of Southern...... migration and to stimulate migratory restlessness in conspecifics. We wished to test if conspecific flight calls influence the flight direction of a nocturnal migrant, the European Robin (Erithacus rubecula), i.e. if flight calls help migrants keeping course. Wild caught birds showing migratory restlessness...... the experimental bird could be activated successively to simulate a migrating Robin cruising E-W, W-E, S-N or N-S at a chosen height (mostly about 40 m), at 10 m/s and emitting Robin flight calls of 80 dB(A) at 1 m. The simulated flight of a "ding" sound served as a control. During an experiment the bird was first...

  2. Extracting bird migration information from C-band Doppler weather radars

    NARCIS (Netherlands)

    van Gasteren, H.; Holleman, I.; Bouten, W.; van Loon, E.; Shamoun-Baranes, J.

    2008-01-01

    Although radar has been used in studies of bird migration for 60 years, there is still no network in Europe for comprehensive monitoring of bird migration. Europe has a dense network of military air surveillance radars but most systems are not directly suitable for reliable bird monitoring. Since

  3. Actogram analysis of free-flying migratory birds

    DEFF Research Database (Denmark)

    Bäckman, Johan; Andersson, Arne; Pedersen, Lykke

    2017-01-01

    The use of accelerometers has become an important part of biologging techniques for large-sized birds with accelerometer data providing information about flight mode, wing-beat pattern, behaviour and energy expenditure. Such data show that birds using much energy-saving soaring/gliding flight like...... frigatebirds and swifts can stay airborne without landing for several months. Successful accelerometer studies have recently been conducted also for free-flying small songbirds during their entire annual cycle. Here we review the principles and possibilities for accelerometer studies in bird migration. We use...... of the life cycle. Accelerometer recording of the annual activity patterns of individual birds will open up a new dimension in bird migration research....

  4. Hovering and intermittent flight in birds

    International Nuclear Information System (INIS)

    Tobalske, Bret W

    2010-01-01

    Two styles of bird locomotion, hovering and intermittent flight, have great potential to inform future development of autonomous flying vehicles. Hummingbirds are the smallest flying vertebrates, and they are the only birds that can sustain hovering. Their ability to hover is due to their small size, high wingbeat frequency, relatively large margin of mass-specific power available for flight and a suite of anatomical features that include proportionally massive major flight muscles (pectoralis and supracoracoideus) and wing anatomy that enables them to leave their wings extended yet turned over (supinated) during upstroke so that they can generate lift to support their weight. Hummingbirds generate three times more lift during downstroke compared with upstroke, with the disparity due to wing twist during upstroke. Much like insects, hummingbirds exploit unsteady mechanisms during hovering including delayed stall during wing translation that is manifest as a leading-edge vortex (LEV) on the wing and rotational circulation at the end of each half stroke. Intermittent flight is common in small- and medium-sized birds and consists of pauses during which the wings are flexed (bound) or extended (glide). Flap-bounding appears to be an energy-saving style when flying relatively fast, with the production of lift by the body and tail critical to this saving. Flap-gliding is thought to be less costly than continuous flapping during flight at most speeds. Some species are known to shift from flap-gliding at slow speeds to flap-bounding at fast speeds, but there is an upper size limit for the ability to bound (∼0.3 kg) and small birds with rounded wings do not use intermittent glides.

  5. Hovering and intermittent flight in birds

    Energy Technology Data Exchange (ETDEWEB)

    Tobalske, Bret W, E-mail: bret.tobalske@mso.umt.ed [Field Research Station at Fort Missoula, Division of Biological Sciences, University of Montana, Missoula, MT 59812 (United States)

    2010-12-15

    Two styles of bird locomotion, hovering and intermittent flight, have great potential to inform future development of autonomous flying vehicles. Hummingbirds are the smallest flying vertebrates, and they are the only birds that can sustain hovering. Their ability to hover is due to their small size, high wingbeat frequency, relatively large margin of mass-specific power available for flight and a suite of anatomical features that include proportionally massive major flight muscles (pectoralis and supracoracoideus) and wing anatomy that enables them to leave their wings extended yet turned over (supinated) during upstroke so that they can generate lift to support their weight. Hummingbirds generate three times more lift during downstroke compared with upstroke, with the disparity due to wing twist during upstroke. Much like insects, hummingbirds exploit unsteady mechanisms during hovering including delayed stall during wing translation that is manifest as a leading-edge vortex (LEV) on the wing and rotational circulation at the end of each half stroke. Intermittent flight is common in small- and medium-sized birds and consists of pauses during which the wings are flexed (bound) or extended (glide). Flap-bounding appears to be an energy-saving style when flying relatively fast, with the production of lift by the body and tail critical to this saving. Flap-gliding is thought to be less costly than continuous flapping during flight at most speeds. Some species are known to shift from flap-gliding at slow speeds to flap-bounding at fast speeds, but there is an upper size limit for the ability to bound ({approx}0.3 kg) and small birds with rounded wings do not use intermittent glides.

  6. Testing an emerging paradigm in migration ecology shows surprising differences in efficiency between flight modes.

    Directory of Open Access Journals (Sweden)

    Adam E Duerr

    Full Text Available To maximize fitness, flying animals should maximize flight speed while minimizing energetic expenditure. Soaring speeds of large-bodied birds are determined by flight routes and tradeoffs between minimizing time and energetic costs. Large raptors migrating in eastern North America predominantly glide between thermals that provide lift or soar along slopes or ridgelines using orographic lift (slope soaring. It is usually assumed that slope soaring is faster than thermal gliding because forward progress is constant compared to interrupted progress when birds pause to regain altitude in thermals. We tested this slope-soaring hypothesis using high-frequency GPS-GSM telemetry devices to track golden eagles during northbound migration. In contrast to expectations, flight speed was slower when slope soaring and eagles also were diverted from their migratory path, incurring possible energetic costs and reducing speed of progress towards a migratory endpoint. When gliding between thermals, eagles stayed on track and fast gliding speeds compensated for lack of progress during thermal soaring. When thermals were not available, eagles minimized migration time, not energy, by choosing energetically expensive slope soaring instead of waiting for thermals to develop. Sites suited to slope soaring include ridges preferred for wind-energy generation, thus avian risk of collision with wind turbines is associated with evolutionary trade-offs required to maximize fitness of time-minimizing migratory raptors.

  7. Testing an emerging paradigm in migration ecology shows surprising differences in efficiency between flight modes.

    Science.gov (United States)

    Duerr, Adam E; Miller, Tricia A; Lanzone, Michael; Brandes, Dave; Cooper, Jeff; O'Malley, Kieran; Maisonneuve, Charles; Tremblay, Junior; Katzner, Todd

    2012-01-01

    To maximize fitness, flying animals should maximize flight speed while minimizing energetic expenditure. Soaring speeds of large-bodied birds are determined by flight routes and tradeoffs between minimizing time and energetic costs. Large raptors migrating in eastern North America predominantly glide between thermals that provide lift or soar along slopes or ridgelines using orographic lift (slope soaring). It is usually assumed that slope soaring is faster than thermal gliding because forward progress is constant compared to interrupted progress when birds pause to regain altitude in thermals. We tested this slope-soaring hypothesis using high-frequency GPS-GSM telemetry devices to track golden eagles during northbound migration. In contrast to expectations, flight speed was slower when slope soaring and eagles also were diverted from their migratory path, incurring possible energetic costs and reducing speed of progress towards a migratory endpoint. When gliding between thermals, eagles stayed on track and fast gliding speeds compensated for lack of progress during thermal soaring. When thermals were not available, eagles minimized migration time, not energy, by choosing energetically expensive slope soaring instead of waiting for thermals to develop. Sites suited to slope soaring include ridges preferred for wind-energy generation, thus avian risk of collision with wind turbines is associated with evolutionary trade-offs required to maximize fitness of time-minimizing migratory raptors.

  8. Spring Bird Migration Phenology in Eilat, Israel

    Directory of Open Access Journals (Sweden)

    Reuven Yosef

    2009-12-01

    Full Text Available Analysis of the mean date of first captures and median arrival dates of spring migration for 34 species of birds at Eilat, Israel, revealed that the earlier a species migrates through Eilat, the greater is the inter-annual variation in the total time of its passage. Birds arrive during spring migration in Eilat in four structured and independent waves. The annual fluctuation in the initial arrival dates (initial capture dates and median dates (median date of all captures, not including recaptures, did not depend on the length of the migratory route. This implies that migrants crossing the Sahara desert depart from their winter quarters on different Julian days in different years. We suggest that negative correlations between the median date of the spring migration of early and late migrants depends upon the easterly (Hamsin wind period. Moreover, we believe that the phenology of all birds during spring migration in Eilat is possibly also determined by external factors such as weather conditions on the African continent or global climatic processes in the Northern hemisphere. Orphean Warblers (Sylvia hortensis show a strong positive correlation (rs=-0.502 of initial capture date with calendar years, whereas other species such as Barred Warbler (S. nisoria; rs = -0.391 and Spotted Flycatcher (Muscicapa striata; rs = -0.398 display an insignificant trend. The Dead Sea Sparrow (Passer moabiticus and Red-Backed Shrike (Lanius collurio are positively correlated regarding initial arrival date and medians of spring migration.

  9. Seasonal associations with urban light pollution for nocturnally migrating bird populations.

    Science.gov (United States)

    La Sorte, Frank A; Fink, Daniel; Buler, Jeffrey J; Farnsworth, Andrew; Cabrera-Cruz, Sergio A

    2017-11-01

    The spatial extent and intensity of artificial light at night (ALAN) has increased worldwide through the growth of urban environments. There is evidence that nocturnally migrating birds are attracted to ALAN, and there is evidence that nocturnally migrating bird populations are more likely to occur in urban areas during migration, especially in the autumn. Here, we test if urban sources of ALAN are responsible, at least in part, for these observed urban associations. We use weekly estimates of diurnal occurrence and relative abundance for 40 nocturnally migrating bird species that breed in forested environments in North America to assess how associations with distance to urban areas and ALAN are defined across the annual cycle. Migratory bird populations presented stronger than expected associations with shorter distances to urban areas during migration, and stronger than expected association with higher levels of ALAN outside and especially within urban areas during migration. These patterns were more pronounced during autumn migration, especially within urban areas. Outside of the two migration periods, migratory bird populations presented stronger than expected associations with longer distances to urban areas, especially during the nonbreeding season, and weaker than expected associations with the highest levels of ALAN outside and especially within urban areas. These findings suggest that ALAN is associated with higher levels of diurnal abundance along the boundaries and within the interior of urban areas during migration, especially in the autumn when juveniles are undertaking their first migration journey. These findings support the conclusion that urban sources of ALAN can broadly effect migratory behavior, emphasizing the need to better understand the implications of ALAN for migratory bird populations. © 2017 John Wiley & Sons Ltd.

  10. Are birds stressed during long-term flights? A wind-tunnel study on circulating corticosterone in the red knot

    NARCIS (Netherlands)

    Jenni-Eiermann, Susanne; Hasselquist, Dennis; Lindstrom, Ake; Koolhaas, Anita; Piersma, Theunis; Lindström, Åke

    2009-01-01

    During endurance flight most birds do not feed and have to rely on their body reserves. Fat and protein is catabolised to meet the high energetic demands. Even though the hormonal regulation of migration is complex and not yet fully understood. the adrenocortical hormone corticosterone crystallizes

  11. Understanding soaring bird migration through interactions and decisions at the individual level

    NARCIS (Netherlands)

    van Loon, E.E.; Shamoun-Baranes, J.; Bouten, W.; Davis, S.L.

    2011-01-01

    Many soaring bird species migrate southwards in autumn from their breeding grounds in Europe and Central Asia towards their wintering grounds. Our knowledge about interactions between migrating birds, thermal selection during migration and mechanisms that lead to flocking or convergent travel

  12. Is there a connection between weather at departure sites, onset of migration and timing of soaring-bird autumn migration in Israel?

    NARCIS (Netherlands)

    Shamoun-Baranes, J.; van Loon, E.E.; Alon, D.; Alpert, P.; Yom-Tov, Y.; Leshem, Y.

    2006-01-01

    Aims Different aspects of soaring-bird migration are influenced by weather. However, the relationship between weather and the onset of soaring-bird migration, particularly in autumn, is not clear. Although long-term migration counts are often unavailable near the breeding areas of many soaring birds

  13. Flight calls and orientation

    DEFF Research Database (Denmark)

    Larsen, Ole Næsbye; Andersen, Bent Bach; Kropp, Wibke

    2008-01-01

    flight calls was simulated by sequential computer controlled activation of five loudspeakers placed in a linear array perpendicular to the bird's migration course. The bird responded to this stimulation by changing its migratory course in the direction of that of the ‘flying conspecifics' but after about......  In a pilot experiment a European Robin, Erithacus rubecula, expressing migratory restlessness with a stable orientation, was video filmed in the dark with an infrared camera and its directional migratory activity was recorded. The flight overhead of migrating conspecifics uttering nocturnal...... 30 minutes it drifted back to its original migration course. The results suggest that songbirds migrating alone at night can use the flight calls from conspecifics as additional cues for orientation and that they may compare this information with other cues to decide what course to keep....

  14. Fish Swimming and Bird/Insect Flight

    Science.gov (United States)

    Wu, Theodore Yaotsu

    2011-01-01

    This expository review is devoted to fish swimming and bird/insect flight. (a) The simple waving motion of an elongated flexible ribbon plate of constant width propagating a wave distally down the plate to swim forward in a fluid, initially at rest, is first considered to provide a fundamental concept on energy conservation. It is generalized to include variations in body width and thickness, with appended dorsal, ventral and caudal fins shedding vortices to closely simulate fish swimming, for which a nonlinear theory is presented for large-amplitude propulsion. (b) For bird flight, the pioneering studies on oscillatory rigid wings are discussed with delineating a fully nonlinear unsteady theory for a two-dimensional flexible wing with arbitrary variations in shape and trajectory to provide a comparative study with experiments. (c) For insect flight, recent advances are reviewed by items on aerodynamic theory and modeling, computational methods, and experiments, for forward and hovering flights with producing leading-edge vortex to yield unsteady high lift. (d) Prospects are explored on extracting prevailing intrinsic flow energy by fish and bird to enhance thrust for propulsion. (e) The mechanical and biological principles are drawn together for unified studies on the energetics in deriving metabolic power for animal locomotion, leading to the surprising discovery that the hydrodynamic viscous drag on swimming fish is largely associated with laminar boundary layers, thus drawing valid and sound evidences for a resounding resolution to the long-standing fish-swim paradox proclaimed by Gray (1936, 1968 ).

  15. Bird flight characteristics near wind turbines in Minnesota

    Science.gov (United States)

    Osborn, R.G.; Dieter, C.D.; Higgins, K.F.; Usgaard, R.E.

    1998-01-01

    During 1994-1995, we saw 70 species of birds on the Buffalo Ridge Wind Resource Area. In both years bird abundance peaked in spring. Red-winged blackbirds (Agelaius phoeniceus), mallards (Anas platyrhynchos), common grackles (Quiscalus quiscula), and barn swallows (Hirundo rustica) were the species most commonly seen. Most birds (82-84%) flew above or below the height range of wind turbine blades (22-55 m). The Buffalo Ridge Wind Resource Area poses little threat to resident or migrating birds at its current operating level.

  16. A Comparitive Analysis of the Influence of Weather on the Flight Altitudes of Birds.

    Science.gov (United States)

    Shamoun-Baranes, Judy; van Loon, Emiel; van Gasteren, Hans; van Belle, Jelmer; Bouten, Willem; Buurma, Luit

    2006-01-01

    Birds pose a serious risk to flight safety worldwide. A Bird Avoidance Model (BAM) is being developed in the Netherlands to reduce the risk of bird aircraft collisions. In order to develop a temporally and spatially dynamic model of bird densities, data are needed on the flight-altitude distribution of birds and how this is influenced by weather. This study focuses on the dynamics of flight altitudes of several species of birds during local flights over land in relation to meteorological conditions.We measured flight altitudes of several species in the southeastern Netherlands using tracking radar during spring and summer 2000. Representatives of different flight strategy groups included four species: a soaring species (buzzard ), an obligatory aerial forager (swift Apus apus), a flapping and gliding species (blackheaded gull Larus ridibundus), and a flapping species (starling Sturnus vulgaris).Maximum flight altitudes varied among species, during the day and among days. Weather significantly influenced the flight altitudes of all species studied. Factors such as temperature, relative humidity, atmospheric instability, cloud cover, and sea level pressure were related to flight altitudes. Different combinations of factors explained 40% 70% of the variance in maximum flight altitudes. Weather affected flight strategy groups differently. Compared to flapping species, buzzards and swifts showed stronger variations in maximum daily altitude and f lew higher under conditions reflecting stronger thermal convection. The dynamic vertical distributions of birds are important for risk assessment and mitigation measures in flight safety as well as wind turbine studies.

  17. Phenotypic flexibility during migration : optimization of organ size contingent on the risks and rewards of fueling and flight?

    NARCIS (Netherlands)

    Piersma, T

    1998-01-01

    Avian long-distance migration involves the storage and expenditure of very large fuel loads. Birds may double in weight before take-off on flights of many 1000 km, and they may lose half their body mass over the subsequent few days that such trips take. Recent studies indicate that in addition to

  18. Do birds in flight respond to (ultra)violet lighting?

    Institute of Scientific and Technical Information of China (English)

    Roel May; Jens Åström; Øyvind Hamre; Espen Lie Dahl

    2017-01-01

    Background: Concerns for bird collisions with wind turbines affect the deployment of onshore and offshore wind-power plants. To avoid delays in consenting processes and to streamline the construction and operation phase, func-tional mitigation measures are required which efficiently reduces bird mortality. Vision is the primary sensory system in birds, which for a number of species also includes the ultraviolet spectrum. Many bird species that are known to collide with offshore wind turbines are sensitive in the violet or ultraviolet spectrum. For species that are mainly active at lower ambient light levels, lighting may deter birds from the lit area. Utilizing (ultra)violet lights may in addition not disturb humans. However, we do not know whether UV-sensitive birds in flight actually respond behaviourally to UV lights. Methods: We therefore tested the efficacy of two types of lights within the violet (400 nm) and ultraviolet (365 nm) spectrum to deter birds from the lit area. These lights were placed vertically and monitored continuously between dusk and dawn using an avian radar system. Results: Relative to control nights, bird flight activity (abundance) was 27% lower when the ultraviolet light was on. Violet light resulted in a 12% decrease in overall abundance, and in addition, a vertical displacement was seen, increasing the average flight altitude by 7 m. Although temporal changes occurred, this effect persisted over the season below 40 m above sea level. Conclusions: Although the results from this pilot study are promising, we argue there still is a long way to go before a potentially functional design to mitigate collisions that has proven to be effective in situ may be in place.

  19. Bone histological correlates of soaring and high-frequency flapping flight in the furculae of birds.

    Science.gov (United States)

    Mitchell, Jessica; Legendre, Lucas J; Lefèvre, Christine; Cubo, Jorge

    2017-06-01

    The furcula is a specialized bone in birds involved in flight function. Its morphology has been shown to reflect different flight styles from soaring/gliding birds, subaqueous flight to high-frequency flapping flyers. The strain experienced by furculae can vary depending on flight type. Bone remodeling is a response to damage incurred from different strain magnitudes and types. In this study, we tested whether a bone microstructural feature, namely Haversian bone density, differs in birds with different flight styles, and reassessed previous work using phylogenetic comparative methods that assume an evolutionary model with additional taxa. We show that soaring birds have higher Haversian bone densities than birds with a flapping style of flight. This result is probably linked to the fact that the furculae of soaring birds provide less protraction force and more depression force than furculae of birds showing other kinds of flight. The whole bone area is another explanatory factor, which confirms the fact that size is an important consideration in Haversian bone development. All birds, however, display Haversian bone development in their furculae, and other factors like age could be affecting the response of Haversian bone development. Copyright © 2017 Elsevier GmbH. All rights reserved.

  20. A comparative analysis of the influence of weather on the flight altitudes of birds

    NARCIS (Netherlands)

    Shamoun-Baranes, J.; van Loon, E.; van Gasteren, H.; van Belle, J.; Bouten, W.; Buurma, L.

    2006-01-01

    Birds pose a serious risk to flight safety worldwide. A Bird Avoidance Model (BAM) is being developed in the Netherlands to reduce the risk of bird-aircraft collisions. In order to develop a temporally and spatially dynamic model of bird densities, data are needed on the flight-altitude distribution

  1. Tracking bird migration at the Baie-des-Sables wind farm site : Innergex II Inc.; Suivi des migrations des oiseaux sur le site d'implantation d'un parc eolien a Baie-des-Sables : Innergex II Inc.

    Energy Technology Data Exchange (ETDEWEB)

    Castonguay, M.; Beauchesne, J.A.; Ouellet, J.F.; Pelletier, N.; Gallant, F.; Lavoie, J. [Pesca Environnement, Maria, PQ (Canada)

    2004-12-21

    The global production of electricity from wind power has increased significantly in recent years. As part of Hydro-Quebec's plans to increase wind power production, Cartier Wind Power plans to install 61 wind turbines at Baie-des-Sables on Quebec's Gaspe Peninsula where wind energy is abundant. This study evaluated the impact of the proposed wind turbine array on birds and their habitat and migration patterns. In particular, it characterized the migratory passage of birds in the area through 900 hours of visual and auditory observation beginning with spring migration, spring nesting to autumnal migration. The behavior of different migratory birds as well as local species was studied and the results of the ornithological inventory were revealed in terms of species abundance and diversity; distribution and use of the territory by birds; migratory activities; period and importance of migration; characterization of displacement; height of flight; direction of migration; and, use of the territory by the avifauna. The inventory identified 121 species of birds including 14 species of raptors which moved mainly along the river and flew very high. The study revealed that although the bird habitats at Baie-des-Sables were already strongly disturbed by agricultural activities, it is unlikely that the turbines will not have any impact on the avifauna. However, most of the wind turbines will be installed in farmers fields, and as such, will not exert additional pressure on the forest medium. The factors that influence the rate of bird collisions with wind turbines were discussed. In order to lessen the impact on birds, it was suggested that installation work should occur outside of the nesting season and that the electrical supply networks should be hidden to limit the harmful effects posed by power lines. 16 refs., 9 tabs., 4 figs., 11 maps, 9 appendices.

  2. Bone-associated gene evolution and the origin of flight in birds.

    Science.gov (United States)

    Machado, João Paulo; Johnson, Warren E; Gilbert, M Thomas P; Zhang, Guojie; Jarvis, Erich D; O'Brien, Stephen J; Antunes, Agostinho

    2016-05-18

    Bones have been subjected to considerable selective pressure throughout vertebrate evolution, such as occurred during the adaptations associated with the development of powered flight. Powered flight evolved independently in two extant clades of vertebrates, birds and bats. While this trait provided advantages such as in aerial foraging habits, escape from predators or long-distance travels, it also imposed great challenges, namely in the bone structure. We performed comparative genomic analyses of 89 bone-associated genes from 47 avian genomes (including 45 new), 39 mammalian, and 20 reptilian genomes, and demonstrate that birds, after correcting for multiple testing, have an almost two-fold increase in the number of bone-associated genes with evidence of positive selection (~52.8 %) compared with mammals (~30.3 %). Most of the positive-selected genes in birds are linked with bone regulation and remodeling and thirteen have been linked with functional pathways relevant to powered flight, including bone metabolism, bone fusion, muscle development and hyperglycemia levels. Genes encoding proteins involved in bone resorption, such as TPP1, had a high number of sites under Darwinian selection in birds. Patterns of positive selection observed in bird ossification genes suggest that there was a period of intense selective pressure to improve flight efficiency that was closely linked with constraints on body size.

  3. Analysis of genomic data as an approach to understanding migration in song birds

    OpenAIRE

    Boss, John

    2015-01-01

    Many species of birds migrate every year thousands of kilometers, relying on sight, memory, magnetic sensors and instincts to find their way across continents. Many juvenile birds travel complicated migration routes without the guidance of more experienced adults. To successfully accomplish this they need instincts that utilizes multiple navigational senses together with a time dependent schedule. Little is known of the genetics behind migration behavior and which cellular processes are invol...

  4. Spring Flyways of Migrating Soaring Birds in Akkar/Northern Lebanon

    International Nuclear Information System (INIS)

    Ramadan Jaradi, Gh.; Ramadan Jaradi, M.

    2015-01-01

    Beale and Ramadan Jaradi initiated in 2001 the first large scale survey in Lebanon to trace the main routes of migrating raptors and other soaring birds, aiming at contributing to the conservation of flyways and stopover sites through the identification of areas where protection is most needed. Nowadays, the study of the flyways and stopover sites at micro level becomes necessary following the development of the national wind atlas map that will assist among others in locating potential wind farms which on their turn may influence the migratory birds flyways, especially that the wind farms use winds for their function and the soaring birds use wind for their transportation. The present work starts from where the work of Beale and Ramadan-Jaradi ended but in an attempt toprovide policy makers, scientists and experts with a conceptual framework, as well as methodological and operational tools for dealing with wind farms impacts and to prevent collisions of birds with blades of wind urbines. The study is meant to be conducted during spring and autumn passage ofbirds. This paper concerns the spring migration as at the time of writing it the autumn migration didn't start yet. The present spring season study revealed among others that the migratory soaring birds that may use the wind ridge lifts for their soaring travel in windy areas are more influenced by two other main factors:1) presence of depressions perpendicular to mountains ridgesand 2) abundance of the thermals in these depressions, a matter that naturally reduce the impact of wind turbines by attracting the birds away from their blade. (author)

  5. Application of ground-truth for classification and quantification of bird movements on migratory bird habitat initiative sites in southwest Louisiana: final report

    Science.gov (United States)

    Barrow, Wylie C.; Baldwin, Michael J.; Randall, Lori A.; Pitre, John; Dudley, Kyle J.

    2013-01-01

    This project was initiated to assess migrating and wintering bird use of lands enrolled in the Natural Resources Conservation Service’s (NRCS) Migratory Bird Habitat Initiative (MBHI). The MBHI program was developed in response to the Deepwater Horizon oil spill in 2010, with the goal of improving/creating habitat for waterbirds affected by the spill. In collaboration with the University of Delaware (UDEL), we used weather surveillance radar data (Sieges 2014), portable marine radar data, thermal infrared images, and visual observations to assess bird use of MBHI easements. Migrating and wintering birds routinely make synchronous flights near dusk (e.g., departure during migration, feeding flights during winter). Weather radars readily detect birds at the onset of these flights and have proven to be useful remote sensing tools for assessing bird-habitat relations during migration and determining the response of wintering waterfowl to wetland restoration (e.g., Wetlands Reserve Program lands). However, ground-truthing is required to identify radar echoes to species or species group. We designed a field study to ground-truth a larger-scale, weather radar assessment of bird use of MBHI sites in southwest Louisiana. We examined seasonal bird use of MBHI fields in fall, winter, and spring of 2011-2012. To assess diurnal use, we conducted total area surveys of MBHI sites in the afternoon, collecting data on bird species composition, abundance, behavior, and habitat use. In the evenings, we quantified bird activity at the MBHI easements and described flight behavior (i.e., birds landing in, departing from, circling, or flying over the MBHI tract). Our field sampling captured the onset of evening flights and spanned the period of collection of the weather radar data analyzed. Pre- and post-dusk surveys were conducted using a portable radar system and a thermal infrared camera. Landbirds, shorebirds, and wading birds were commonly found on MBHI fields during diurnal

  6. Metabolic 'engines' of flight drive genome size reduction in birds.

    Science.gov (United States)

    Wright, Natalie A; Gregory, T Ryan; Witt, Christopher C

    2014-03-22

    The tendency for flying organisms to possess small genomes has been interpreted as evidence of natural selection acting on the physical size of the genome. Nonetheless, the flight-genome link and its mechanistic basis have yet to be well established by comparative studies within a volant clade. Is there a particular functional aspect of flight such as brisk metabolism, lift production or maneuverability that impinges on the physical genome? We measured genome sizes, wing dimensions and heart, flight muscle and body masses from a phylogenetically diverse set of bird species. In phylogenetically controlled analyses, we found that genome size was negatively correlated with relative flight muscle size and heart index (i.e. ratio of heart to body mass), but positively correlated with body mass and wing loading. The proportional masses of the flight muscles and heart were the most important parameters explaining variation in genome size in multivariate models. Hence, the metabolic intensity of powered flight appears to have driven genome size reduction in birds.

  7. Fuel load and flight ranges of blackcaps Sylvia atricapilla in northern Iberia during autumn and spring migrations

    Directory of Open Access Journals (Sweden)

    JUAN ARIZAGA, EMILIO BARBA

    2009-12-01

    Full Text Available Fuel accumulation, mainly as fatty acids, is one of the main characteristics of migratory birds. Studying to what extent each population or species manages fuel load and how it varies along routes of migration or between seasons (autumn and spring migrations is crucial to our understanding of bird migration strategies. Our aim here was to analyse whether migratory blackcaps Sylvia atricapilla passing through northern Iberia differ in their mean fuel loads, rate of fuel accumulation and 'potential' flight ranges between migration seasons. Blackcaps were mist netted for 4 h-periods beginning at dawn from 16 September to 15 November 2003–2005, and from 1 March to 30 April 2004–2006 in a European Atlantic hedgerow at Loza, northern Iberia. Both fuel load and fuel deposition rate (this latter assessed with difference in body mass of within-season recaptured individuals were higher in autumn than in spring. Possible hypotheses explaining these results could be seasonal-associated variations in food availability (likely lower during spring than during autumn, the fact that a fraction of the migrants captured in spring could breed close to the study area and different selective pressures for breeding and wintering [Current Zoology 55 (6: 401–410, 2009].

  8. How birds weather the weather: avian migration in the mid-latitudes

    NARCIS (Netherlands)

    Kemp, M.U.

    2012-01-01

    The life cycle of many bird species involves the twice-annual movement between a breeding ground and a wintering ground that we refer to as `migration'. To complete these journeys, birds must successfully navigate many obstacles including a dynamic atmosphere. To make optimal use of this

  9. Wind-governed flight altitudes of nocturnal spring migrants over the ...

    African Journals Online (AJOL)

    Flight costs make up a large proportion of energy expenditure during migration and are strongly dependent on atmospheric conditions aloft. Birds crossing the Sahara can take advantage of the fairly reliable trade-wind regime. In our study, we investigated whether birds adapt flight altitude to minimise energy or water loss.

  10. Homing pigeons externally exposed to Deepwater Horizon crude oil change flight performance and behavior.

    Science.gov (United States)

    Perez, Cristina R; Moye, John K; Cacela, Dave; Dean, Karen M; Pritsos, Chris A

    2017-11-01

    The Deepwater Horizon oil spill was the largest in U.S. history, contaminating thousands of miles of coastal habitat and affecting the lives of many avian species. The Gulf of Mexico is a critical bird migration route area and migrants that were oiled but did not suffer mortality as a direct result of the spill faced unpredictable fates. This study utilized homing pigeons as a surrogate species for migratory birds to investigate the effects a single low level external oiling event has on the flight performance and behavior of birds flying repeated 161 km flights. Data from GPS data loggers showed that lightly oiled pigeons changed their flight paths, increased their flight durations by 2.6 fold, increased their flight distances by 28 km and subsequently decreased their route efficiencies. Oiled birds also exhibited reduced rate of weight gain between flights. Our data suggest that contaminated birds surviving the oil spill may have experienced flight impairment and reduced refueling abilities, likely reducing overall migration speed. Our findings contribute new information on how oil spills affect avian species, as the effects of oil on the flight behavior of long distance free-flying birds have not been previously described. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Tracking migrating birds

    DEFF Research Database (Denmark)

    Willemoes, Mikkel

    habitats with those in rural habitats. Some species have decreased the frequency of migrants and migration distance in urban environments, and others have not. The other manuscript describes the small scale movements of three different Palaearctic migrants during winter in Africa in a farmland habitat....... In another species, environmental conditions are not a good predictor of movements, and possibly effects of timing constraints or food type play a role. Two manuscripts focus on the effects of human-induced habitat alterations on migratory behaviour. One compares the movements of partial migrants in urban...... and a forest reserve. In the degraded habitat all species used more space, although the consequence on bird density is less clear. Two manuscripts relate the migratory movements of a long-distance migrant with models of navigation. One compares model predictions obtained by simulation with actual movements...

  12. Hippocampal Astrocytes in Migrating and Wintering Semipalmated Sandpiper Calidris pusilla.

    Science.gov (United States)

    Carvalho-Paulo, Dario; de Morais Magalhães, Nara G; de Almeida Miranda, Diego; Diniz, Daniel G; Henrique, Ediely P; Moraes, Isis A M; Pereira, Patrick D C; de Melo, Mauro A D; de Lima, Camila M; de Oliveira, Marcus A; Guerreiro-Diniz, Cristovam; Sherry, David F; Diniz, Cristovam W P

    2017-01-01

    Seasonal migratory birds return to the same breeding and wintering grounds year after year, and migratory long-distance shorebirds are good examples of this. These tasks require learning and long-term spatial memory abilities that are integrated into a navigational system for repeatedly locating breeding, wintering, and stopover sites. Previous investigations focused on the neurobiological basis of hippocampal plasticity and numerical estimates of hippocampal neurogenesis in birds but only a few studies investigated potential contributions of glial cells to hippocampal-dependent tasks related to migration. Here we hypothesized that the astrocytes of migrating and wintering birds may exhibit significant morphological and numerical differences connected to the long-distance flight. We used as a model the semipalmated sandpiper Calidris pusilla , that migrates from northern Canada and Alaska to South America. Before the transatlantic non-stop long-distance component of their flight, the birds make a stopover at the Bay of Fundy in Canada. To test our hypothesis, we estimated total numbers and compared the three-dimensional (3-D) morphological features of adult C. pusilla astrocytes captured in the Bay of Fundy ( n = 249 cells) with those from birds captured in the coastal region of Bragança, Brazil, during the wintering period ( n = 250 cells). Optical fractionator was used to estimate the number of astrocytes and for 3-D reconstructions we used hierarchical cluster analysis. Both morphological phenotypes showed reduced morphological complexity after the long-distance non-stop flight, but the reduction in complexity was much greater in Type I than in Type II astrocytes. Coherently, we also found a significant reduction in the total number of astrocytes after the transatlantic flight. Taken together these findings suggest that the long-distance non-stop flight altered significantly the astrocytes population and that morphologically distinct astrocytes may play

  13. Hippocampal Astrocytes in Migrating and Wintering Semipalmated Sandpiper Calidris pusilla

    Directory of Open Access Journals (Sweden)

    Dario Carvalho-Paulo

    2018-01-01

    Full Text Available Seasonal migratory birds return to the same breeding and wintering grounds year after year, and migratory long-distance shorebirds are good examples of this. These tasks require learning and long-term spatial memory abilities that are integrated into a navigational system for repeatedly locating breeding, wintering, and stopover sites. Previous investigations focused on the neurobiological basis of hippocampal plasticity and numerical estimates of hippocampal neurogenesis in birds but only a few studies investigated potential contributions of glial cells to hippocampal-dependent tasks related to migration. Here we hypothesized that the astrocytes of migrating and wintering birds may exhibit significant morphological and numerical differences connected to the long-distance flight. We used as a model the semipalmated sandpiper Calidris pusilla, that migrates from northern Canada and Alaska to South America. Before the transatlantic non-stop long-distance component of their flight, the birds make a stopover at the Bay of Fundy in Canada. To test our hypothesis, we estimated total numbers and compared the three-dimensional (3-D morphological features of adult C. pusilla astrocytes captured in the Bay of Fundy (n = 249 cells with those from birds captured in the coastal region of Bragança, Brazil, during the wintering period (n = 250 cells. Optical fractionator was used to estimate the number of astrocytes and for 3-D reconstructions we used hierarchical cluster analysis. Both morphological phenotypes showed reduced morphological complexity after the long-distance non-stop flight, but the reduction in complexity was much greater in Type I than in Type II astrocytes. Coherently, we also found a significant reduction in the total number of astrocytes after the transatlantic flight. Taken together these findings suggest that the long-distance non-stop flight altered significantly the astrocytes population and that morphologically distinct astrocytes

  14. Do birds of like feather flock together? The use of a novel 13C+D combustion isotope analyzer to track bird migration

    Science.gov (United States)

    Saad, N.

    2011-12-01

    Information on spring migration routes, geographic linkages among winter, spring, and breeding locations, and potential geographic effects on arrival body condition of a variety of avian species is so far little known. Stable isotope ratios are exquisitely sensitive to the biochemistry of living organisms and the nutrients available to them. Isotope ratios provide detailed knowledge useful in a variety of fields, including birds migration, through a combination of stable-isotope measurements of carbon (13C/12C) and hydrogen (D/H) isotopes of flight feathers and breast feathers of tissues representing different periods of dietary integration and body composition analyses. Associations among specific geographic areas, habitat use, and arrival condition can be elucidated through the measurement of these dual isotopes. We report here on the development of a novel laser spectroscopy based system for the simultaneous analysis of the stable isotope ratios of carbon (13C/12C) and hydrogen (D/H) that is robust, easy-to-use, and is the first stable isotope ratio analysis system to combine the measurement of 13C/12C and D/H in one simple analysis from a bulk organic sample with an application to bird migration. The system comprises a combustion module to convert the organic sample into CO2 and H2O and a Cavity Ring-Down Spectrometer (CRDS) that analyzes the combustion species inside an optical cavity based on the molecular absorption of individual isotopomers. This CRDS uses dual lasers to target the four isotpomers of interest: 12CO2, 13CO2, H2O and HDO. The system delivers a typical precision of 0.1 permil for δ13C and 1.5 permil for δD that parallels that achieved by IRMS, but with an unprecedented simplicity that allows ecologists to leverage the science and elucidate the avian migration patterns.

  15. Follow-up on the migration of birds of prey at the Baie-des-Sables wind park site : preliminary report; Suivi de la migration des oiseaux de proie sur le site d'implantation du parc eolien de Baie-des-Sables : rapport preliminaire

    Energy Technology Data Exchange (ETDEWEB)

    Castonguay, M.; Beauchesne, J.A.; Boulianne, F.; Bujold, J.; Ouellet, J.F. [Pesca Environnement, Maria, PQ (Canada)

    2005-06-15

    Cartier Wind Power plans to install a wind turbine array at Baie-des-Sables in the Gaspe Peninsula. This study evaluated the impact of the proposed wind turbine array on the thousands of birds of prey that fly along Quebec's St. Lawrence River each year. Their migration patterns were evaluated through visual and auditory observations during the springtime reproductive and nesting season. The proposed 109.5 MW wind turbine park in Baie-des-Sables was presented to the Quebec Ministry of Sustainable Development, Environment and Parks. In order to complete a feasibility study for this project, it was necessary to document and characterize the spring migration pattern of birds of prey in the area. An inventory of raptors was carried out between March 31 and May 23, 2005. This current study supplemented an existing inventory from a previous study carried out in the spring of 2004. This current study included data on dates of observations of the migratory birds during the monitoring period. Nine species of birds of prey were identified. Overall, 448 individual birds were observed over a total period of 92 hours. With 137 sightings of the red-tailed hawk and 95 sightings of the rough-legged hawk, these 2 species were the most frequently indexed species, accounting for 51.8 per cent of the sightings. No evidence of nesting particular to birds of prey was observed at the site. The flight patterns of the birds were also observed with reference to height and direction of flight. 7 refs., 4 tabs., 1 fig., 3 appendices.

  16. Temperature-influenced energetics model for migrating waterfowl

    Science.gov (United States)

    Aagaard, Kevin; Thogmartin, Wayne E.; Lonsdorg, Eric V.

    2018-01-01

    Climate and weather affect avian migration by influencing when and where birds fly, the energy costs and risks of flight, and the ability to sense cues necessary for proper navigation. We review the literature of the physiology of avian migration and the influence of climate, specifically temperature, on avian migration dynamics. We use waterfowl as a model guild because of the ready availability of empirical physiological data and their enormous economic value, but our discussion and expectations are broadly generalizable to migratory birds in general. We detail potential consequences of an increasingly warm climate on avian migration, including the possibility of the cessation of migration by some populations and species. Our intent is to lay the groundwork for including temperature effects on energetic gains and losses of migratory birds with the expected consequences of increasing temperatures into a predictive modeling framework. To this end, we provide a simulation of migration progression exclusively focused on the influence of temperature on the physiological determinants of migration. This simulation produced comparable results to empirically derived and observed values for different migratory factors (e.g., body fat content, flight range, departure date). By merging knowledge from the arenas of avian physiology and migratory theory we have identified a clear need for research and have developed hypotheses for a path forward.

  17. Artificial light at night confounds broad-scale habitat use by migrating birds

    Science.gov (United States)

    McLaren, James D.; Buler, Jeffrey J.; Schreckengost, Tim; Smolinsky, Jaclyn A.; Boone, Matthew; van Loon, E. Emiel; Dawson, Deanna K.; Walters, Eric L.

    2018-01-01

    With many of the world's migratory bird populations in alarming decline, broad-scale assessments of responses to migratory hazards may prove crucial to successful conservation efforts. Most birds migrate at night through increasingly light-polluted skies. Bright light sources can attract airborne migrants and lead to collisions with structures, but might also influence selection of migratory stopover habitat and thereby acquisition of food resources. We demonstrate, using multi-year weather radar measurements of nocturnal migrants across the northeastern U.S., that autumnal migrant stopover density increased at regional scales with proximity to the brightest areas, but decreased within a few kilometers of brightly-lit sources. This finding implies broad-scale attraction to artificial light while airborne, impeding selection for extensive forest habitat. Given that high-quality stopover habitat is critical to successful migration, and hindrances during migration can decrease fitness, artificial lights present a potentially heightened conservation concern for migratory bird populations.

  18. Local temperature fine-tunes the timing of spring migration in birds

    DEFF Research Database (Denmark)

    Tøttrup, Anders P.; Rainio, Kalle; Coppack, Timothy

    2010-01-01

    and predict consequences of climatic change for migratory birds. In order to better understand migration phenology and adaptation in environmental changes, we here assess the scale at which weather affects timing of spring migration in passerine birds. We use three commonly used proxies of spring......-time climatic conditions: (1) vegetation "greenness" (NDVI) in Europe, (2) local spring temperatures in northern Europe, and (3) the North Atlantic Oscillation Index (NAO) as predictors of the phenology of avian migration as well as the strength of their effect on different subsets of populations...... breeding area. Local temperature was the best single predictor of phenology with the highest explanatory power achieved in combination with NAO. Furthermore, early individuals are more affected by climatic variation compared to individuals on later passage, indicating that climatic change affects subsets...

  19. Artificial light at night confounds broad-scale habitat use by migrating birds

    NARCIS (Netherlands)

    McLaren, J.D.; Buler, J.J.; Schreckengost, T.; Smolinsky, J.A.; Boone, M.; van Loon, E.E.; Dawson, D.K.; Walters, E.L.

    With many of the world's migratory bird populations in alarming decline, broad-scale assessments of responses to migratory hazards may prove crucial to successful conservation efforts. Most birds migrate at night through increasingly light-polluted skies. Bright light sources can attract airborne

  20. Physiological modelling of oxygen consumption in birds during flight

    Science.gov (United States)

    Bishop; Butler

    1995-01-01

    This study combines data on changes in cardiovascular variables with body mass (Mb) and with exercise intensity to model the oxygen supply available to birds during flight. Its main purpose is to provide a framework for identifying the factors involved in limiting aerobic power input to birds during flight and to suggest which cardiovascular variables are the most likely to have been influenced by natural selection when considering both allometric and adaptive variation. It is argued that natural selection has acted on heart rate (fh) and cardiac stroke volume (Vs), so that the difference in the arteriovenous oxygen content (CaO2-Cv¯O2) in birds, both at rest and during flight, is independent of Mb. Therefore, the Mb exponent for oxygen consumption (V(dot)O2) during flight can be estimated from measurements of heart rate and stroke volume. Stroke volume is likely to be directly proportional to heart mass (Mh) and, using empirical data, values for the Mb coefficients and exponents of various cardiovascular variables are estimated. It is concluded that, as found for mammals, fh is the main adaptive variable when considering allometric variation, although Mh also shows a slight scaling effect. Relative Mh is likely to be the most important when considering adaptive specialisations. The Fick equation may be represented as: (V(dot)O2)Mbz = (fh)Mbw x (Vs)Mbx x (CaO2 - Cv¯O2)Mby , where w, x, y, z are the body mass exponents for each variable and the terms in parentheses represent the Mb coefficients. Utilising this formula and data from the literature, the scaling of minimum V(dot)O2 during flight for bird species with a 'high aerobic capacity' (excluding hummingbirds) is calculated to be: 166Mb0.77±0.09 = 574Mb-0.19±0.02 x 3.48Mb0.96±0.02 x 0.083Mb0.00±0.05 , and for hummingbirds (considered separately owing to their unique wing kinematics) it is: 314Mb0.90±0.22 = 617Mb-0.10±0.06 x 6.13Mb1.00±0.11 x 0.083Mb0.00±0.05 . These results are largely dependent on the

  1. A generalizable energetics-based model of avian migration to facilitate continental-scale waterbird conservation

    Science.gov (United States)

    Lonsdorf, Eric V.; Thogmartin, Wayne E.; Jacobi, Sarah; Coppen, Jorge; Davis, Amélie Y.; Fox, Timothy J.; Heglund, Patricia J.; Johnson, Rex; Jones, Tim; Kenow, Kevin P.; Lyons, James E.; Luke, Kirsten E.; Still, Shannon; Tavernia, Brian G.

    2016-01-01

    Conserving migratory birds is made especially difficult because of movement among spatially disparate locations across the annual cycle. In light of challenges presented by the scale and ecology of migratory birds, successful conservation requires integrating objectives, management, and monitoring across scales, from local management units to ecoregional and flyway administrative boundaries. We present an integrated approach using a spatially explicit energetic-based mechanistic bird migration model useful to conservation decision-making across disparate scales and locations. This model moves a mallard-like bird (Anas platyrhynchos), through spring and fall migration as a function of caloric gains and losses across a continental scale energy landscape. We predicted with this model that fall migration, where birds moved from breeding to wintering habitat, took a mean of 27.5 days of flight with a mean seasonal survivorship of 90.5% (95% CI = 89.2%, 91.9%) whereas spring migration took a mean of 23.5 days of flight with mean seasonal survivorship of 93.6% (95% CI = 92.5%, 94.7%). Sensitivity analyses suggested that survival during migration was sensitive to flight speed, flight cost, the amount of energy the animal could carry and the spatial pattern of energy availability, but generally insensitive to total energy availability per se. Nevertheless, continental patterns in the bird-use days occurred principally in relation to wetland cover and agricultural habitat in the fall. Bird-use days were highest in both spring and fall in the Mississippi Alluvial Valley and along the coast and near-shore environments of South Carolina. Spatial sensitivity analyses suggested that locations nearer to migratory endpoints were less important to survivorship; for instance, removing energy from a 1,036 km2 stopover site at a time from the Atlantic Flyway suggested coastal areas between New Jersey and North Carolina, including Chesapeake Bay and the North Carolina piedmont, are

  2. Emergence of long distance bird migrations: a new model integrating global climate changes

    Science.gov (United States)

    Louchart, Antoine

    2008-12-01

    During modern birds history, climatic and environmental conditions have evolved on wide scales. In a continuously changing world, landbirds annual migrations emerged and developed. However, models accounting for the origins of these avian migrations were formulated with static ecogeographic perspectives. Here I reviewed Cenozoic paleoclimatic and paleontological data relative to the palearctic paleotropical long distance (LD) migration system. This led to propose a new model for the origin of LD migrations, the ‘shifting home’ model (SHM). It is based on a dynamic perspective of climate evolution and may apply to the origins of most modern migrations. Non-migrant tropical African bird taxa were present at European latitudes during most of the Cenozoic. Their distribution limits shifted progressively toward modern tropical latitudes during periods of global cooling and increasing seasonality. In parallel, decreasing winter temperatures in the western Palearctic drove shifts of population winter ranges toward the equator. I propose that this induced the emergence of most short distance migrations, and in turn LD migrations. This model reconciliates ecologically tropical ancestry of most LD migrants with predominant winter range shifts, in accordance with requirements for heritable homing. In addition, it is more parsimonious than other non-exclusive models. Greater intrinsic plasticity of winter ranges implied by the SHM is supported by recently observed impacts of the present global warming on migrating birds. This may induce particular threats to some LD migrants. The ancestral, breeding homes of LD migrants were not ‘northern’ or ‘southern’ but shifted across high and middle latitudes while migrations emerged through winter range shifts themselves.

  3. Researches regarding the influence of the weather on the flight of the white storks (Ciconia ciconia in the spring migration across the Doamnei River hydrographical basin (Argeş County, Romania (II. Other considerations about the migration over the area.

    Directory of Open Access Journals (Sweden)

    Adrian MESTECANEANU

    2011-11-01

    Full Text Available In this last part of the series of articles concerning the migration of the white storks (Ciconia ciconia in the Doamnei River hydrographical basin, the authors make some considerations regarding the overflown areas and habitats, the aerial activity dependingon the lapse of time and the intra- and inter-specific bonds. The most individuals were observed in the hilly area, flying principally over the settlements and forests. April was the most intense month regarding the migration, the maximum of the aerial activity being between 16:00 and 17:00 for the observations per hour and between 17:00 and 18:00 for the observed individuals per hour. The birds avoided to fly on bad weather conditions and they preferred to use the soaring and gliding flights. Usually, they did not emit any sound.Rarely, the storks were temporarily accompanied in flight by other birds (Pernis apivorus, Accipiter nisus and Falco tinnunculus.

  4. Collision risks at sea: species composition and altitude distributions of birds in Danish offshore wind farms

    Energy Technology Data Exchange (ETDEWEB)

    Blew, J.; Hoffmann, M.; Nehls, G. [BioConsult SH (Germany)

    2007-07-01

    This study investigates the collision risks of birds in operating offshore wind farms, focussing on all bird species present in the direct vicinity of the wind farms, their altitude distribution and reactions. The project was conducted jointly by BioConsult SH and the University of Hamburg in the two Danish offshore wind farms Horns Rev (North Sea) and Nysted (Baltic Sea) in the framework of a Danish-German cooperation and financed by the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU). Data were collected between March 2005 and November 2006, using a ship anchored at the edge of the offshore wind farms. In this way, bird species of all sizes could be considered. Daytime observations yielded data on species composition, flight routes and potential reactions of the birds. Radar observations provided altitude distributions inside and outside the wind farm area and also reactions. The results shall help to further describe and assess the collision risk of different species groups. Since data analysis is still running, exemplary results will be presented here. 114 species have been recorded in Nysted and 99 in Horns Rev, approximately 65% of which have been observed inside the wind farm areas. Migrating birds seem to avoid flying into the wind farms, whereas individuals present in the areas for extended time periods utilize areas within the wind farms. While a barrier effect exists for species on migration, resident species probably have a higher collision risk. Raptors migrating during daylight frequently enter the wind farm area on their flight routes, correcting their flight paths in order to avoid collisions. Radar results show that during times of intensive migration, the proportion of birds flying at high altitudes and thus above windmill height is higher than in times of low migration intensity. Consequently, there is a lower proportion of migrating birds flying within the risk area. Data will be further analysed to

  5. Water requirements and drinking rates of homing pigeons: A consideration for exposure risk of migratory birds.

    Science.gov (United States)

    Perez, Cristina R; Moye, John K; Pritsos, Chris A

    2017-09-01

    Access to water along a bird's migratory flyway is essential during the vital process of migration. Because of the scarcity of water in some environments, there is potential for migratory birds to encounter and drink from contaminated bodies of water. Ingestion of contaminated water may cause injury and compromise flying ability, leading to a disruption of migration. To determine injury to birds from potential exposure, it is essential to know not only the concentration of a given contaminant in the water but also the quantity and rate of water consumption by the birds. Homing pigeons (Columba livia) were used in a series of experiments to determine differences in drinking behavior after various flights and after periods of resting. Results from the present study demonstrate that homing pigeons' water consumption is dramatically different when assessed according to activity, flight distance, and time elapsed after flight. This suggests that the drinking rates of birds during migration are extremely important and much greater than estimated using traditional exposure assessment procedures. Thus, exposure to contaminants via drinking water may be greatly underestimated, and the rate of water consumption should be considered when estimating potential exposure risk to avian species. Integr Environ Assess Manag 2017;13:870-876. © 2017 SETAC. © 2017 SETAC.

  6. Excess Baggage for Birds: Inappropriate Placement of Tags on Gannets Changes Flight Patterns

    Science.gov (United States)

    Vandenabeele, Sylvie P.; Grundy, Edward; Friswell, Michael I.; Grogan, Adam; Votier, Stephen C.; Wilson, Rory P.

    2014-01-01

    Devices attached to flying birds can hugely enhance our understanding of their behavioural ecology for periods when they cannot be observed directly. For this, scientists routinely attach units to either birds' backs or their tails. However, inappropriate payload distribution is critical in aircraft and, since birds and planes are subject to the same laws of physics during flight, we considered aircraft aerodynamic constraints to explain flight patterns displayed by northern gannets Sula bassana equipped with (small ca. 14 g) tail- and back-mounted accelerometers and (larger ca. 30 g) tail-mounted GPS units. Tail-mounted GPS-fitted birds showed significantly higher cumulative numbers of flap-glide cycles and a higher pitch angle of the tail than accelerometer-equipped birds, indicating problems with balancing inappropriately placed weights with knock-on consequences relating to energy expenditure. These problems can be addressed by carefully choosing where to place tags on birds according to the mass of the tags and the lifestyle of the subject species. PMID:24671007

  7. Migrating birds and carnivores introduce ticks and tick borne pathogens to Denmark – but are they also a public health risk?

    DEFF Research Database (Denmark)

    Bødker, Rene; Vrbová, Erika; Højgaard, Jesper

    Since the end of the ice age, spring migrating birds from Africa and Europe and autumn migrating birds from Northern Scandinavia have entered Denmark, and recently a small wave of long migrating carnivores have started arriving in Denmark from Central Europe. Theoretically, migrating birds could...... introduce new tick species as well as tick-associated pathogens to Denmark. These migrating animals may also carry ticks and pathogens which already exist in native tick populations in Denmark. The potential supplement of native ticks and existing pathogens to the established high density tick populations...... in Danish forest and nature areas can be expected to be of little practical importance. However, some of the infected ticks, introduced by migrating birds, may be deposited in private gardens and public parks that are otherwise not able to sustain a viable tick population. Migrating birds may therefore...

  8. Using high resolution GPS tracking data of bird flight for meteorological observations

    NARCIS (Netherlands)

    Treep, J.; Bohrer, G.; Shamoun-Baranes, J.; Duriez, O.; Prata de Moraes Frasson, R.; Bouten, W.

    2016-01-01

    Bird flight is strongly influenced by local meteorological conditions. With increasing amounts of high-frequency GPS data of bird movement becoming available, as tags become cheaper and lighter, opportunities are created to obtain large datasets of quantitative meteorological information from

  9. Hemispheric-scale wind selection facilitates bar-tailed godwit circum-migration of the Pacific

    Science.gov (United States)

    Gill, Robert E.; Douglas, David C.; Handel, Colleen M.; Tibbitts, T. Lee; Hufford, Gary; Piersma, Theunis

    2014-01-01

    The annual 29 000 km long migration of the bar-tailed godwit, Limosa lapponica baueri, around the Pacific Ocean traverses what is arguably the most complex and seasonally structured atmospheric setting on Earth. Faced with marked variation in wind regimes and storm conditions across oceanic migration corridors, individuals must make critical decisions about when and where to fly during nonstop flights of a week's duration or longer. At a minimum, their decisions will affect wind profitability and thus reduce energetic costs of migration; in the extreme, poor decisions or unpredictable weather events will risk survival. We used satellite telemetry to track the annual migration of 24 bar-tailed godwits and analysed their flight performance relative to wind conditions during three major migration legs between nonbreeding grounds in New Zealand and breeding grounds in Alaska. Because flight altitudes of birds en route were unknown, we modelled flight efficiency at six geopotential heights across each migratory segment. Birds selected departure dates when atmospheric conditions conferred the greatest wind assistance both at departure and throughout their flights. This behaviour suggests that there exists a cognitive mechanism, heretofore unknown among migratory birds, that allows godwits to assess changes in weather conditions that are linked (i.e. teleconnected) across widely separated atmospheric regions. Godwits also showed adaptive flexibility in their response not only to cues related to seasonal changes in macrometeorology, such as spatial shifting of storm tracks and temporal periods of cyclogenesis, but also to cues associated with stochastic events, especially at departure sites. Godwits showed limits to their response behaviours, however, especially relative to rapidly developing stochastic events while en route. We found that flight efficiency depended significantly upon altitude and hypothesize that godwits exhibit further adaptive flexibility by varying

  10. The natural link between Europe and Africa - 2.1 billion birds on migration

    NARCIS (Netherlands)

    Hahn, S.M.; Bauer, S.; Liechti, F.

    2009-01-01

    The Palaearctic–African migration system comprises enormous numbers of birds travelling between Europe and Africa twice each year. Migratory birds may form strong links between the two continents given they can act as both transport vehicles for parasites and diseases as well as temporary consumers

  11. American Exceptionalism: Population Trends and Flight Initiation Distances in Birds from Three Continents

    Science.gov (United States)

    Møller, Anders Pape; Samia, Diogo S. M.; Weston, Mike A.; Guay, Patrick-Jean; Blumstein, Daniel T.

    2014-01-01

    Background All organisms may be affected by humans' increasing impact on Earth, but there are many potential drivers of population trends and the relative importance of each remains largely unknown. The causes of spatial patterns in population trends and their relationship with animal responses to human proximity are even less known. Methodology/Principal Finding We investigated the relationship between population trends of 193 species of bird in North America, Australia and Europe and flight initiation distance (FID); the distance at which birds take flight when approached by a human. While there is an expected negative relationship between population trend and FID in Australia and Europe, we found the inverse relationship for North American birds; thus FID cannot be used as a universal predictor of vulnerability of birds. However, the analysis of the joint explanatory ability of multiple drivers (farmland breeding habitat, pole-most breeding latitude, migratory habit, FID) effects on population status replicated previously reported strong effects of farmland breeding habitat (an effect apparently driven mostly by European birds), as well as strong effects of FID, body size, migratory habit and continent. Farmland birds are generally declining. Conclusions/Significance Flight initiation distance is related to population trends in a way that differs among continents opening new research possibilities concerning the causes of geographic differences in patterns of anti-predator behavior. PMID:25226165

  12. Flight range, fuel load and the impact of climate change on the journeys of migrant birds

    Science.gov (United States)

    Sheard, Catherine; Butchart, Stuart H. M.

    2018-01-01

    Climate change is predicted to increase migration distances for many migratory species, but the physiological and temporal implications of longer migratory journeys have not been explored. Here, we combine information about species' flight range potential and migratory refuelling requirements to simulate the number of stopovers required and the duration of current migratory journeys for 77 bird species breeding in Europe. Using tracking data, we show that our estimates accord with recorded journey times and stopovers for most species. We then combine projections of altered migratory distances under climate change with models of avian flight to predict future migratory journeys. We find that 37% of migratory journeys undertaken by long-distance migrants will necessitate an additional stopover in future. These greater distances and the increased number of stops will substantially increase overall journey durations of many long-distance migratory species, a factor not currently considered in climate impact studies. PMID:29467262

  13. Can variation in risk of nest predation explain altitudinal migration in tropical birds?

    Science.gov (United States)

    Boyle, W Alice

    2008-03-01

    Migration is among the best studied of animal behaviors, yet few empirical studies have tested hypotheses explaining the ultimate causes of these cyclical annual movements. Fretwell's (1980) hypothesis predicts that if nest predation explains why many tropical birds migrate uphill to breed, then predation risk must be negatively associated with elevation. Data from 385 artificial nests spanning 2,740 m of elevation on the Atlantic slope of Costa Rica show an overall decline in predation with increasing elevation. However, nest predation risk was highest at intermediate elevations (500-650 m), not at lowest elevations. The proportion of nests depredated by different types of predators differed among elevations. These results imply that over half of the altitudinal migrant bird species in this region migrate to safer breeding areas than their non-breeding areas, suggesting that variation in nest predation risk could be an important benefit of uphill migrations of many species.

  14. Ecomorphology of the external flight apparatus of blackcaps (Sylvia atricapilla) with different migration behavior.

    Science.gov (United States)

    Fiedler, Wolfgang

    2005-06-01

    An analysis of the external flight apparatus of 700 blackcaps from eight different populations (sedentary to long-distance migrators) is presented. With increasing migration distances of populations, (1) wing length, aspect ratio, and wing pointedness increase; (2) wing load decreases; (3) slots on the wing tips become relatively shorter; (4) the alula tends to be shorter in relation to wing length; and (5) the tail is shorter in relation to wing length. Although body mass increases from southern to northern populations, changes in wing length and wing area are two to three times larger than expected for simple isometric relationships. Regarding the aerodynamic background of these changes, it can be stated that traits for energy-effective flight are more strongly developed and traits for maneuverability are less developed in birds traveling longer distances, presumably as a consequence of trade-offs. Nonmigratory blackcaps from Madeira and the Cape Verde islands do not always show the traits we would expect in view of their sedentary behavior. This can be seen as a result of recent colonization of these islands by migrants or of selection by factors other than migration behavior. In migratory populations, changes between the first and the second set of primaries during first complete molt show almost the same pattern as the changes from nonmigratory to migratory populations. During molt of the primaries, blackcaps of nonmigratory populations do not show these changes. Hybrids between migrating and nonmigrating blackcap populations (Moscow and Madeira) showed intermediate values between parent populations in wing length, wing shape, and wing area; in the other variables they resembled either parent population.

  15. An implantable instrument for studying the long-term flight biology of migratory birds

    Energy Technology Data Exchange (ETDEWEB)

    Spivey, Robin J., E-mail: r.spivey@bangor.ac.uk, E-mail: c.bishop@bangor.ac.uk; Bishop, Charles M., E-mail: r.spivey@bangor.ac.uk, E-mail: c.bishop@bangor.ac.uk [Department of Biological Sciences, Bangor University, Gwynedd LL57 2UW (United Kingdom)

    2014-01-15

    The design of an instrument deployed in a project studying the high altitude Himalayan migrations of bar-headed geese (Anser indicus) is described. The electronics of this archival datalogger measured 22 × 14 × 6.5 mm, weighed 3 g, was powered by a ½AA-sized battery weighing 10 g and housed in a transparent biocompatible tube sealed with titanium electrodes for electrocardiography (ECG). The combined weight of 32 g represented less than 2% of the typical bodyweight of the geese. The primary tasks of the instrument were to continuously record a digitised ECG signal for heart-rate determination and store 12-bit triaxial accelerations sampled at 100 Hz with 15% coverage over each 2 min period. Measurement of atmospheric pressure provided an indication of altitude and rate of ascent or descent during flight. Geomagnetic field readings allowed for latitude estimation. These parameters were logged twice per minute along with body temperature. Data were stored to a memory card of 8 GB capacity. Instruments were implanted in geese captured on Mongolian lakes during the breeding season when the birds are temporarily flightless due to moulting. The goal was to collect data over a ten month period, covering both southward and northward migrations. This imposed extreme constraints on the design's power consumption. Raw ECG can be post-processed to obtain heart-rate, allowing improved rejection of signal interference due to strenuous activity of locomotory muscles during flight. Accelerometry can be used to monitor wing-beat frequency and body kinematics, and since the geese continued to flap their wings continuously even during rather steep descents, act as a proxy for biomechanical power. The instrument enables detailed investigation of the challenges faced by the geese during these arduous migrations which typically involve flying at extreme altitudes through cold, low density air where oxygen availability is significantly reduced compared to sea level.

  16. Flight response of slope-soaring birds to seasonal variation in thermal generation

    Science.gov (United States)

    Adam E. Duerr; Tricia A. Miller; Michael Lanzone; David Brandes; Jeff Cooper; Kieran O' Malley; Charles Maisonneuve; Junior A. Tremblay; Todd. Katzner

    2014-01-01

    Animals respond to a variety of environmental cues, including weather conditions, when migrating. Understanding the relationship between weather and migration behaviour is vital to assessing time- and energy limitations of soaring birds. Different soaring modes have different efficiencies, are dependent upon different types of subsidized lift and are weather dependent...

  17. Arthropods and associated arthropod-borne diseases transmitted by migrating birds. The case of ticks and tick-borne pathogens.

    Science.gov (United States)

    Sparagano, Olivier; George, David; Giangaspero, Annunziata; Špitalská, Eva

    2015-09-30

    Geographic spread of parasites and pathogens poses a constant risk to animal health and welfare, particularly given that climate change is expected to potentially expand appropriate ranges for many key species. The spread of deleterious organisms via trade routes and human travelling is relatively closely controlled, though represents only one possible means of parasite/pathogen distribution. The transmission via natural parasite/pathogen movement between geographic locales, is far harder to manage. Though the extent of such movement may be limited by the relative inability of many parasites and pathogens to actively migrate, passive movement over long distances may still occur via migratory hosts. This paper reviews the potential role of migrating birds in the transfer of ectoparasites and pathogens between geographic locales, focusing primarily on ticks. Bird-tick-pathogen relationships are considered, and evidence provided of long-range parasite/pathogen transfer from one location to another during bird migration events. As shown in this paper not only many different arthropod species are carried by migrating birds but consequently these pests carry many different pathogens species which can be transmitted to the migrating birds or to other animal species when those arthropods are dropping during these migrations. Data available from the literature are provided highlighting the need to understand better dissemination paths and disease epidemiology. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Overseas seed dispersal by migratory birds.

    Science.gov (United States)

    Viana, Duarte S; Gangoso, Laura; Bouten, Willem; Figuerola, Jordi

    2016-01-13

    Long-distance dispersal (LDD) promotes the colonization of isolated and remote habitats, and thus it has been proposed as a mechanism for explaining the distributions of many species. Birds are key LDD vectors for many sessile organisms such as plants, yet LDD beyond local and regional scales has never been directly observed nor quantified. By sampling birds caught while in migratory flight by GPS-tracked wild falcons, we show that migratory birds transport seeds over hundreds of kilometres and mediate dispersal from mainland to oceanic islands. Up to 1.2% of birds that reached a small island of the Canary Archipelago (Alegranza) during their migration from Europe to Sub-Saharan Africa carried seeds in their guts. The billions of birds making seasonal migrations each year may then transport millions of seeds. None of the plant species transported by the birds occurs in Alegranza and most do not occur on nearby Canary Islands, providing a direct example of the importance of environmental filters in hampering successful colonization by immigrant species. The constant propagule pressure generated by these LDD events might, nevertheless, explain the colonization of some islands. Hence, migratory birds can mediate rapid range expansion or shifts of many plant taxa and determine their distribution. © 2016 The Author(s).

  19. Avian influenza H5N1 viral and bird migration networks in Asia

    Science.gov (United States)

    Tian, Huaivu; Zhou, Sen; Dong, Lu; Van Boeckel, Thomas P.; Cui, Yujun; Newman, Scott H.; Takekawa, John Y.; Prosser, Diann J.; Xiao, Xiangming; Wu, Yarong; Cazelles, Bernard; Huang, Shanqian; Yang, Ruifu; Grenfell, Bryan T.; Xu, Bing

    2015-01-01

    The spatial spread of the highly pathogenic avian influenza virus H5N1 and its long-term persistence in Asia have resulted in avian influenza panzootics and enormous economic losses in the poultry sector. However, an understanding of the regional long-distance transmission and seasonal patterns of the virus is still lacking. In this study, we present a phylogeographic approach to reconstruct the viral migration network. We show that within each wild fowl migratory flyway, the timing of H5N1 outbreaks and viral migrations are closely associated, but little viral transmission was observed between the flyways. The bird migration network is shown to better reflect the observed viral gene sequence data than other networks and contributes to seasonal H5N1 epidemics in local regions and its large-scale transmission along flyways. These findings have potentially far-reaching consequences, improving our understanding of how bird migration drives the periodic reemergence of H5N1 in Asia.

  20. Multicore Considerations for Legacy Flight Software Migration

    Science.gov (United States)

    Vines, Kenneth; Day, Len

    2013-01-01

    In this paper we will discuss potential benefits and pitfalls when considering a migration from an existing single core code base to a multicore processor implementation. The results of this study present options that should be considered before migrating fault managers, device handlers and tasks with time-constrained requirements to a multicore flight software environment. Possible future multicore test bed demonstrations are also discussed.

  1. Flight range, fuel load and the impact of climate change on the journeys of migrant birds.

    Science.gov (United States)

    Howard, Christine; Stephens, Philip A; Tobias, Joseph A; Sheard, Catherine; Butchart, Stuart H M; Willis, Stephen G

    2018-02-28

    Climate change is predicted to increase migration distances for many migratory species, but the physiological and temporal implications of longer migratory journeys have not been explored. Here, we combine information about species' flight range potential and migratory refuelling requirements to simulate the number of stopovers required and the duration of current migratory journeys for 77 bird species breeding in Europe. Using tracking data, we show that our estimates accord with recorded journey times and stopovers for most species. We then combine projections of altered migratory distances under climate change with models of avian flight to predict future migratory journeys. We find that 37% of migratory journeys undertaken by long-distance migrants will necessitate an additional stopover in future. These greater distances and the increased number of stops will substantially increase overall journey durations of many long-distance migratory species, a factor not currently considered in climate impact studies. © 2018 The Authors.

  2. Combining radar systems to get a 3D - picture of the bird migration

    NARCIS (Netherlands)

    Liechti, F.; Dokter, A.; Shamoun, J.; van Gasteren, H.; Holleman, I.

    2008-01-01

    For military training flights bird strikes en route are still a severe problem. To reduce collisions an international project has been launched by the European Space agency (ESA), aiming 1) for a compilation of information on current bird movements by various sensors, 2) to combine them in a single

  3. The Nocturnal Avian Migration Experiment Final Campaign Report

    Energy Technology Data Exchange (ETDEWEB)

    Stepanian, P. M. [Univ. of Oklahoma, Norman, OK (United States); Horton, K. G. [Univ. of Oklahoma, Norman, OK (United States)

    2016-03-01

    Remote sensing techniques are playing a greater role in ornithology, and radar has proven a valuable tool for high resolution, long-term observations of airborne animals. The major disadvantage in radar remote sensing is the current inability to gain taxonomic information from these measurements. One solution is the incorporation of collocated acoustic monitoring that can provide recordings of species-specific nocturnal flight calls of migrating birds in flight. In addition, by taking multichannel recordings of these calls, the position of the calling bird can be calculated and linked to collocated radar measurements.

  4. Influenza a virus migration and persistence in North American wild birds.

    Directory of Open Access Journals (Sweden)

    Justin Bahl

    Full Text Available Wild birds have been implicated in the emergence of human and livestock influenza. The successful prediction of viral spread and disease emergence, as well as formulation of preparedness plans have been hampered by a critical lack of knowledge of viral movements between different host populations. The patterns of viral spread and subsequent risk posed by wild bird viruses therefore remain unpredictable. Here we analyze genomic data, including 287 newly sequenced avian influenza A virus (AIV samples isolated over a 34-year period of continuous systematic surveillance of North American migratory birds. We use a Bayesian statistical framework to test hypotheses of viral migration, population structure and patterns of genetic reassortment. Our results reveal that despite the high prevalence of Charadriiformes infected in Delaware Bay this host population does not appear to significantly contribute to the North American AIV diversity sampled in Anseriformes. In contrast, influenza viruses sampled from Anseriformes in Alberta are representative of the AIV diversity circulating in North American Anseriformes. While AIV may be restricted to specific migratory flyways over short time frames, our large-scale analysis showed that the long-term persistence of AIV was independent of bird flyways with migration between populations throughout North America. Analysis of long-term surveillance data provides vital insights to develop appropriately informed predictive models critical for pandemic preparedness and livestock protection.

  5. The effect of the Sep wind park near Oosterbierum, Friesland, The Netherlands, on birds

    International Nuclear Information System (INIS)

    Winkelman, J.E.

    1992-01-01

    The study concerns 1984-1991. The wind park consists of 18 three-bladed 300 kW horizontal axis wind turbines of 35 meters height, and a rotor diameter of 30 meters, seven meteorological towers, and three cluster and control buildings. Aspects studied included disturbance of breeding, resting or feeding, and migrating birds, behavior of birds approaching the wind turbines during the day and night, and bird victims due to collision with the wind turbines and the meteorological towers. The flight behavior of birds approaching the wind park system during daylight is also dealt with. For at least a fifth of the observations it was noted whether the birds passing within 100 meters distance of a turbine showed a reaction or not. The proportion of the reactions was related to the wind park in operation or not in operation, and to the distance between the wind turbines, species, flight height, the passing distance, wind direction and wind force. Secondly the flight path of birds approaching the wind park from eastern directions during daylight (real autumn migration) and from southern directions during late afternoon (flights of gulls to night roosts) was studied in detail. Significantly more reactions (11-18%) were recorded with the wind park fully operational compared to the wind park not operational (2%). In total 2203 flight paths of birds approaching the wind park were recorded during 151 hours of observation. The test results showed that a passing distance of less or more than 100 meters of the nearest wind turbine did not affect the proportion of reactions. Several reaction types and combinations were noted, varying from gradual and calm reactions (circa 75%), and panic reactions, occurring just before or while passing the wind turbines. The reactions are shift in the flight path in the horizontal plane (30%), shift in the flight path in the vertical plane (14%), one passing attempt (87%), an accelerated wing beat (14%), an alteration of the angle of the body (21%)

  6. The effects of a wind farm on birds in a migration point: the Strait of Gibraltar.

    OpenAIRE

    Lucas, Manuela de; Janss, Guyonne, F.E.; Ferrer, Miguel

    2004-01-01

    The interaction between birds and wind turbines is an important factor to consider when a wind farm is constructed. A wind farm and two control areas were studied in Tarifa (Andalusia Province, southern Spain, 30STF590000–30STE610950).Variables were studied along linear transects in each area and observations of flight were also recorded from fixed points in the wind farm. The main purpose of our research was to determine the impact and the degree of flight behavioural change in birds flights...

  7. How birds direct impulse to minimize the energetic cost of foraging flight

    Science.gov (United States)

    Chin, Diana; Lentink, David

    2017-11-01

    Foraging arboreal birds frequently hop and fly between branches by extending long-jumps with a few wingbeats. Their legs transfer impulse to the branch during takeoff and landing, and their wings transfer impulse to the air to support their bodyweight during flight. To determine the mechanical energy tradeoffs of this bimodal locomotion, we studied how Pacific parrotlets transfer impulse during voluntary perch-to-perch flights. We tested five foraging flight variations by varying the inclination and distance between instrumented perches inside a novel aerodynamic force platform. This setup enables direct, time-resolved in vivo measurements of both leg and wing forces, which we combined with high-speed kinematics to develop a new bimodal long-jump and flight model. The model demonstrates how parrotlets direct their leg impulse to minimize the mechanical energy needed for each flight, and further shows how even a single proto-wingbeat would have significantly lengthened the long-jump of foraging arboreal dinosaurs. By directing jumps and flapping their wings, both extant and ancestral birds could thus improve foraging effectiveness. Similarly, bimodal robots could also employ these locomotion strategies to traverse cluttered environments more effectively.

  8. Habitat associations of migrating and overwintering grassland birds in Southern Texas

    Science.gov (United States)

    Igl, Lawrence D.; Ballard, Bart M.

    1999-01-01

    We report on the habitat associations of 21 species of grassland birds overwintering in or migrating through southern Texas, during 1991-1992 and 1992-1993. Ninety percent of our grassland bird observations were made during winter and spring, and only 10% occurred during fall. Grassland species made up a high proportion of the total bird densities in grassland and shrub-grassland habitats, but much lower proportions in the habitats with more woody vegetation. Fewer grassland species were observed in grassland and woodland than in brushland, parkland, and shrub-grassland habitats. Grassland birds generally were found in higher densities in habitats that had woody canopy coverage of < 30%; densities of grassland birds were highest in shrub-grassland habitat and lowest in woodland habitat. Species that are grassland specialists on their breeding grounds tended to be more habitat specific during the nonbreeding season compared to shrub-grassland specialists, which were more general in their nonbreeding-habitat usage. Nonetheless, our data demonstrate that grassland birds occur in a variety of habitats during the nonbreeding season and seem to occupy a broader range of habitats than previously described.

  9. Prevalence of West Nile virus in migratory birds during spring and fall migration

    Science.gov (United States)

    Dusek, Robert J.; McLean, R.G.; Kramer, L.D.; Ubico, S.R.; Dupuis, A.P.; Ebel, G.D.; Guptill, S.C.

    2009-01-01

    To investigate the role of migratory birds in the dissemination of West Nile virus (WNV), we measured the prevalence of infectious WNV and specific WNV neutralizing antibodies in birds, principally Passeriformes, during spring and fall migrations in the Atlantic and Mississippi flyways from 2001-2003. Blood samples were obtained from 13,403 birds, representing 133 species. Specific WNV neutralizing antibody was detected in 254 resident and migratory birds, representing 39 species, and was most commonly detected in northern cardinals (Cardinalis cardinalis) (9.8%, N = 762) and gray catbirds (Dumetella carolinensis) (3.2%,N = 3188). West Nile virus viremias were detected in 19 birds, including 8 gray catbirds, and only during the fall migratory period. These results provide additional evidence that migratory birds may have been a principal agent for the spread of WNV in North America and provide data on the occurrence of WNV in a variety of bird species. Copyright ?? 2009 by The American Society of Tropical Medicine and Hygiene.

  10. Variation in wing characteristics of monarch butterflies during migration: Earlier migrants have redder and more elongated wings

    Directory of Open Access Journals (Sweden)

    Satterfield Dara A.

    2014-01-01

    Full Text Available The migration of monarch butterflies (Danaus plexippus in North America has a number of parallels with long-distance bird migration, including the fact that migratory populations of monarchs have larger and more elongated forewings than residents. These characteristics likely serve to optimize flight performance in monarchs, as they also do with birds. A question that has rarely been addressed thus far in birds or monarchs is if and how wing characteristics vary within a migration season. Individuals with superior flight performance should migrate quickly, and/or with minimal stopovers, and these individuals should be at the forefront of the migratory cohort. Conversely, individuals with poor flight performance and/or low endurance would be more likely to fall behind, and these would comprise the latest migrants. Here we examined how the wing morphology of migrating monarchs varies to determine if wing characteristics of early migrants differ from late migrants. We measured forewing area, elongation (length/width, and redness, which has been shown to predict flight endurance in monarchs. Based on a collection of 75 monarchs made one entire season (fall 2010, results showed that the earliest migrants (n = 20 in this cohort had significantly redder and more elongated forewings than the latest migrants (n = 17. There was also a non-significant tendency for early migrants to have larger forewing areas. These results suggest that the pace of migration in monarchs is at least partly dependent on the properties of their wings. Moreover, these data also raise a number of questions about the ultimate fate of monarchs that fall behind

  11. Using radar to advance migratory bird management: An interagency collaboration

    Science.gov (United States)

    Sojda, R.; Ruth, J.M.; Barrow, W.C.; Dawson, D.K.; Diehl, R.H.; Manville, A.; Green, M.T.; Krueper, D.J.; Johnston, S.

    2005-01-01

    Migratory birds face many changes to the landscapes they traverse and the habitats they use. Wind turbines and communications towers, which pose hazards to birds and bats in flight, are being erected across the United States and offshore. Human activities can also destroy or threaten habitats critical to birds during migratory passage, and climate change appears to be altering migratory patterns. The U.S. Fish and Wildlife Service (USFWS) and other agencies are under increasing pressure to identify and evaluate movement patterns and habitats used during migration and other times.

  12. Classification of Birds and Bats Using Flight Tracks

    Energy Technology Data Exchange (ETDEWEB)

    Cullinan, Valerie I.; Matzner, Shari; Duberstein, Corey A.

    2015-05-01

    Classification of birds and bats that use areas targeted for offshore wind farm development and the inference of their behavior is essential to evaluating the potential effects of development. The current approach to assessing the number and distribution of birds at sea involves transect surveys using trained individuals in boats or airplanes or using high-resolution imagery. These approaches are costly and have safety concerns. Based on a limited annotated library extracted from a single-camera thermal video, we provide a framework for building models that classify birds and bats and their associated behaviors. As an example, we developed a discriminant model for theoretical flight paths and applied it to data (N = 64 tracks) extracted from 5-min video clips. The agreement between model- and observer-classified path types was initially only 41%, but it increased to 73% when small-scale jitter was censored and path types were combined. Classification of 46 tracks of bats, swallows, gulls, and terns on average was 82% accurate, based on a jackknife cross-validation. Model classification of bats and terns (N = 4 and 2, respectively) was 94% and 91% correct, respectively; however, the variance associated with the tracks from these targets is poorly estimated. Model classification of gulls and swallows (N ≥ 18) was on average 73% and 85% correct, respectively. The models developed here should be considered preliminary because they are based on a small data set both in terms of the numbers of species and the identified flight tracks. Future classification models would be greatly improved by including a measure of distance between the camera and the target.

  13. Morphological constraints on changing avian migration phenology.

    Science.gov (United States)

    Møller, A P; Rubolini, D; Saino, N

    2017-06-01

    Many organisms at northern latitudes have responded to climate warming by advancing their spring phenology. Birds are known to show earlier timing of spring migration and reproduction in response to warmer springs. However, species show heterogeneous phenological responses to climate warming, with those that have not advanced or have delayed migration phenology experiencing population declines. Although some traits (such as migration distance) partly explain heterogeneity in phenological responses, the factors affecting interspecies differences in the responsiveness to climate warming have yet to be fully explored. In this comparative study, we investigate whether variation in wing aspect ratio (reflecting relative wing narrowness), an ecomorphological trait that is strongly associated with flight efficiency and migratory behaviour, affects the ability to advance timing of spring migration during 1960-2006 in a set of 80 European migratory bird species. Species with larger aspect ratio (longer and narrower wings) showed smaller advancement of timing of spring migration compared to species with smaller aspect ratio (shorter and wider wings) while controlling for phylogeny, migration distance and other life-history traits. In turn, migration distance positively predicted aspect ratio across species. Hence, species that are better adapted to migration appear to be more constrained in responding phenologically to rapid climate warming by advancing timing of spring migration. Our findings corroborate the idea that aspect ratio is a major evolutionary correlate of migration, and suggest that selection for energetically efficient flights, as reflected by high aspect ratio, may hinder phenotypically plastic/microevolutionary adjustments of migration phenology to ongoing climatic changes. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

  14. Assessing Arboreal Adaptations of Bird Antecedents: Testing the Ecological Setting of the Origin of the Avian Flight Stroke

    Science.gov (United States)

    Dececchi, T. Alexander; Larsson, Hans C. E.

    2011-01-01

    The origin of avian flight is a classic macroevolutionary transition with research spanning over a century. Two competing models explaining this locomotory transition have been discussed for decades: ground up versus trees down. Although it is impossible to directly test either of these theories, it is possible to test one of the requirements for the trees-down model, that of an arboreal paravian. We test for arboreality in non-avian theropods and early birds with comparisons to extant avian, mammalian, and reptilian scansors and climbers using a comprehensive set of morphological characters. Non-avian theropods, including the small, feathered deinonychosaurs, and Archaeopteryx, consistently and significantly cluster with fully terrestrial extant mammals and ground-based birds, such as ratites. Basal birds, more advanced than Archaeopteryx, cluster with extant perching ground-foraging birds. Evolutionary trends immediately prior to the origin of birds indicate skeletal adaptations opposite that expected for arboreal climbers. Results reject an arboreal capacity for the avian stem lineage, thus lending no support for the trees-down model. Support for a fully terrestrial ecology and origin of the avian flight stroke has broad implications for the origin of powered flight for this clade. A terrestrial origin for the avian flight stroke challenges the need for an intermediate gliding phase, presents the best resolved series of the evolution of vertebrate powered flight, and may differ fundamentally from the origin of bat and pterosaur flight, whose antecedents have been postulated to have been arboreal and gliding. PMID:21857918

  15. Assessing arboreal adaptations of bird antecedents: testing the ecological setting of the origin of the avian flight stroke.

    Directory of Open Access Journals (Sweden)

    T Alexander Dececchi

    Full Text Available The origin of avian flight is a classic macroevolutionary transition with research spanning over a century. Two competing models explaining this locomotory transition have been discussed for decades: ground up versus trees down. Although it is impossible to directly test either of these theories, it is possible to test one of the requirements for the trees-down model, that of an arboreal paravian. We test for arboreality in non-avian theropods and early birds with comparisons to extant avian, mammalian, and reptilian scansors and climbers using a comprehensive set of morphological characters. Non-avian theropods, including the small, feathered deinonychosaurs, and Archaeopteryx, consistently and significantly cluster with fully terrestrial extant mammals and ground-based birds, such as ratites. Basal birds, more advanced than Archaeopteryx, cluster with extant perching ground-foraging birds. Evolutionary trends immediately prior to the origin of birds indicate skeletal adaptations opposite that expected for arboreal climbers. Results reject an arboreal capacity for the avian stem lineage, thus lending no support for the trees-down model. Support for a fully terrestrial ecology and origin of the avian flight stroke has broad implications for the origin of powered flight for this clade. A terrestrial origin for the avian flight stroke challenges the need for an intermediate gliding phase, presents the best resolved series of the evolution of vertebrate powered flight, and may differ fundamentally from the origin of bat and pterosaur flight, whose antecedents have been postulated to have been arboreal and gliding.

  16. Thermal soaring flight of birds and unmanned aerial vehicles

    International Nuclear Information System (INIS)

    Akos, Zsuzsa; Nagy, Mate; Vicsek, Tamas; Leven, Severin

    2010-01-01

    Thermal soaring saves much energy, but flying large distances in this form represents a great challenge for birds, people and unmanned aerial vehicles (UAVs). The solution is to make use of the so-called thermals, which are localized, warmer regions in the atmosphere moving upward with a speed exceeding the descent rate of birds and planes. Saving energy by exploiting the environment more efficiently is an important possibility for autonomous UAVs as well. Successful control strategies have been developed recently for UAVs in simulations and in real applications. This paper first presents an overview of our knowledge of the soaring flight and strategy of birds, followed by a discussion of control strategies that have been developed for soaring UAVs both in simulations and applications on real platforms. To improve the accuracy of the simulation of thermal exploitation strategies we propose a method to take into account the effect of turbulence. Finally, we propose a new GPS-independent control strategy for exploiting thermal updrafts.

  17. Researches regarding the influence of the weather on the flight of the white storks (Ciconia ciconia in the spring migration across the Doamnei River hydrographical basin (Argeş county, Romania

    Directory of Open Access Journals (Sweden)

    Adrian MESTECĂNEANU

    2011-05-01

    Full Text Available The authors show a preliminary study regarding the influence of the weather on the flight (soaring, gliding and flapping flight of the white storks (Ciconia ciconia in the spring migration across the Doamnei River hydrographical basin. The research is based on 289 observations and 3153 individuals observed during 1998 – 2010. The lapse of time, the temperature of the air, the atmospheric nebulosity, the type of clouds, and the wind intensity were considered. We stated that the presence of the ascendant air played a major role in the migratory flight, this rising air being used by birds in their economical flight that combine the soaring flight and the gliding one.

  18. Basal metabolic rate declines during long-distance migratory flight in great knots

    NARCIS (Netherlands)

    Battley, PF; Dekinga, A; Dietz, MW; Piersma, T; Tang, SX; Hulsman, K; Battley, Phil F.; Tang, Sixian

    2001-01-01

    Great Knots (Calidris tenuirostris) make one of the longest migratory flights in the avian world, flying almost 5500 km from Australia to China during northward migration. We measured basal metabolic rate (BMR) and body composition in birds before and after this flight and found that BMR decreased

  19. Soaring migratory birds avoid wind farm in the Isthmus of Tehuantepec, southern Mexico.

    Science.gov (United States)

    Villegas-Patraca, Rafael; Cabrera-Cruz, Sergio A; Herrera-Alsina, Leonel

    2014-01-01

    The number of wind farms operating in the Isthmus of Tehuantepec, southern Mexico, has rapidly increased in recent years; yet, this region serves as a major migration route for various soaring birds, including Turkey Vultures (Cathartes aura) and Swainson's Hawks (Buteo swainsoni). We analyzed the flight trajectories of soaring migrant birds passing the La Venta II wind farm during the two migratory seasons of 2011, to determine whether an avoidance pattern existed or not. We recorded three polar coordinates for the flight path of migrating soaring birds that were detected using marine radar, plotted the flight trajectories and estimated the number of trajectories that intersected the polygon defined by the wind turbines of La Venta II. Finally, we estimated the actual number of intersections per kilometer and compared this value with the null distributions obtained by running 10,000 simulations of our datasets. The observed number of intersections per kilometer fell within or beyond the lower end of the null distributions in the five models proposed for the fall season and in three of the four models proposed for the spring season. Flight trajectories had a non-random distribution around La Venta II, suggesting a strong avoidance pattern during fall and a possible avoidance pattern during spring. We suggest that a nearby ridgeline plays an important role in this pattern, an issue that may be incorporated into strategies to minimize the potential negative impacts of future wind farms on soaring birds. Studies evaluating these issues in the Isthmus of Tehuantepec have not been previously published; hence this work contributes important baseline information about the movement patterns of soaring birds and its relationship to wind farms in the region.

  20. The potential of fruit trees to enhance converted habitats for migrating birds in southern Mexico

    Science.gov (United States)

    Foster, M.S.

    2007-01-01

    Migration routes used by Nearctic migrant birds can cover great distances; they also differ among species, within species, and between years and seasons. As a result, migration routes for an entire migratory avifauna can encompass broad geographic areas, making it impossible to protect continuous stretches of habitat sufficient to connect the wintering and breeding grounds for most species. Consequently, ways to enhance habitats converted for human use (i.e. for pasture, crop cultivation, human settlement) as stopover sites for migrants are especially important. Shelterbelts around pastures and fields, if planted with species targeted to support migrant (and resident) bird species that naturally occupy mature forest habitats and that are at least partially frugivorous, could be a powerful enhancement tool for such species, if the birds will enter the converted areas to feed. I tested this approach for Nearctic migrant birds during the spring migration through an area in Chiapas, Mexico. Mature forest tree species whose fruits are eaten by birds were surveyed. Based on life form, crop size and fruit characteristics, I selected three tree species for study: Cymbopetalum mayanum (Annonaceae), Bursera simaruba (Burseraceae) and Trophis racemosa (Moraceae). I compared the use of fruits of these species by migrants and residents in forest with their use of the fruits of isolated individuals of the same species in pasture and cropland. All three plant species were useful for enhancing converted habitats for forest-occupying spring migrants, although species differed in the degree to which they entered disturbed areas to feed on the fruits. These tree species could probably enhance habitats for migrants at sites throughout the natural geographic ranges of the plants; in other geographic areas for other target bird groups, other tree species might be more appropriate.

  1. Spatio-temporal dynamics of global H5N1 outbreaks match bird migration patterns

    Directory of Open Access Journals (Sweden)

    Yali Si

    2009-11-01

    Full Text Available The global spread of highly pathogenic avian influenza H5N1 in poultry, wild birds and humans, poses a significant pandemic threat and a serious public health risk. An efficient surveillance and disease control system relies on the understanding of the dispersion patterns and spreading mechanisms of the virus. A space-time cluster analysis of H5N1 outbreaks was used to identify spatio-temporal patterns at a global scale and over an extended period of time. Potential mechanisms explaining the spread of the H5N1 virus, and the role of wild birds, were analyzed. Between December 2003 and December 2006, three global epidemic phases of H5N1 influenza were identified. These H5N1 outbreaks showed a clear seasonal pattern, with a high density of outbreaks in winter and early spring (i.e., October to March. In phase I and II only the East Asia Australian flyway was affected. During phase III, the H5N1 viruses started to appear in four other flyways: the Central Asian flyway, the Black Sea Mediterranean flyway, the East Atlantic flyway and the East Africa West Asian flyway. Six disease cluster patterns along these flyways were found to be associated with the seasonal migration of wild birds. The spread of the H5N1 virus, as demonstrated by the space-time clusters, was associated with the patterns of migration of wild birds. Wild birds may therefore play an important role in the spread of H5N1 over long distances. Disease clusters were also detected at sites where wild birds are known to overwinter and at times when migratory birds were present. This leads to the suggestion that wild birds may also be involved in spreading the H5N1 virus over short distances.

  2. Waterbird flight initiation distances at Barberspan Bird Sanctuary, South Africa

    Directory of Open Access Journals (Sweden)

    Carina Coetzer

    2017-05-01

    Full Text Available With tourism in South Africa expanding, the number of avitourists increases. The increase in infrastructure and human activities in protected areas, if not managed properly, can be harmful to birds. Flight initiation distances (FID can be used as a method to monitor habituation to disturbances. This study was performed at the Barberspan Bird Sanctuary, North West province, South Africa, to determine the levels of habituation among waterbirds and make appropriate recommendations regarding the management of the reserve. Our results indicated a 0.29 m increase in FID per gram reported mean biomass. Compared with conspecific or congeneric birds from Australia, Europe and North America, South African birds have relatively larger FIDs to human disturbance, which may indicate lower habituation. We also calculated buffer zones based on the maximum FID of the waterbirds for three mass groups. These buffer zones were then matched with the spatial distribution of the birds along the shoreline. We recommend that the mean FID for the blacksmith lapwing, Vanellus armatus (62 m, can be used as approach distance outside the breeding season in areas where the birds are sparsely distributed and 104 m during the breeding season in breeding areas. A large buffer of 200 m is suggested for areas with threatened, sensitive and skittish species. However, it is still preferable for avitourists to use the bird hides along the shores. Conservation implications: This study provides information for conservation management at Barberspan, based on typical birder activity. Smaller birds would need smaller buffer zones, while larger birds need much greater distances from observers to minimise disturbance. Similar studies can be applied elsewhere.

  3. Follow-up on the migration of birds of prey at L'Anse-a-Valleau wind park site : preliminary report; Suivi de la migration des oiseaux de proie sur le site d'implantation du parc eolien de l'Anse-a-Valleau : rapport preliminaire

    Energy Technology Data Exchange (ETDEWEB)

    Castonguay, M.; Beauchesne, J.A.; Boulianne, F.; Bujold, J.; Ouellet, J.F. [Pesca Environnement, Maria, PQ (Canada)

    2005-06-15

    Cartier Wind Power plans to install a wind turbine array at L'Anse-a-Valleau in the Gaspe Peninsula. This study evaluated the impact of the proposed wind turbine array on the thousands of birds of prey that fly along Quebec's St. Lawrence River each year. Their migration patterns were evaluated through visual and auditory observations during the springtime reproductive and nesting season. The proposed 100.5 MW wind turbine park in L'Anse-a-Valleau was presented to the Quebec Ministry of Sustainable Development, Environment and Parks. In order to complete a feasibility study for this project, it was necessary to document and characterize the spring migration pattern of birds of prey in the area. An inventory of raptors was carried out between April 1 and May 14, 2005. This current study supplemented an existing inventory from a previous study carried out in the spring of 2003. This current study included data on dates of observations of the migratory birds over a 12 day period in L'Anse-a-Valleau as well as Lac du Grand Etang. During the 12 day observation period, bird watching took place for about four hours a day, from 10:00 to 15:00, given favourable weather conditions such as absence of rain and good visibility. Overall, 14 birds of prey were observed over a period of 44 hours. With 5 sightings, the red-tailed hawk was the most frequently observed species during this study. Very few signs of migration were noticed in L'Anse-a-Valleau. The results indicate that this region is not on the migratory path of birds of prey during their flight on the south side of the Saint-Lawrence River. 6 refs., 1 tab., 4 figs., 3 appendices.

  4. Effects of Vehicle Speed on Flight Initiation by Turkey Vultures: Implications for Bird-Vehicle Collisions

    Science.gov (United States)

    DeVault, Travis L.; Blackwell, Bradley F.; Seamans, Thomas W.; Lima, Steven L.; Fernández-Juricic, Esteban

    2014-01-01

    The avoidance of motorized vehicles is a common challenge for birds in the modern world. Birds appear to rely on antipredator behaviors to avoid vehicles, but modern vehicles (automobiles and aircraft) are faster than natural predators. Thus, birds may be relatively ill-equipped, in terms of sensory capabilities and behaviors, to avoid vehicles. We examined the idea that birds may be unable to accurately assess particularly high speeds of approaching vehicles, which could contribute to miscalculations in avoidance behaviors and ultimately cause collisions. We baited turkey vultures (Cathartes aura) to roads with animal carcasses and measured flight initiation distance and effective time-to-collision in response to a truck driving directly towards vultures from a starting distance of 1.13 km and at one of three speeds: 30, 60, or 90 kph (no vultures were struck). Flight initiation distance of vultures increased by a factor of 1.85 as speed increased from 30 to 90 kph. However, for 90-kph approaches there was no clear trend in flight initiation distance across replicates: birds appeared equally likely to initiate escape behavior at 40 m as at 220 m. Time-to-collision decreased by a factor of 0.62 with approach speeds from 30 to 90 kph. Also, at 90 kph, four vehicle approaches (17%) resulted in near collisions with vultures (time-to-collision ≤1.7 s), compared to none during 60 kph approaches and one during 30 kph approaches (4%). Our findings suggest that antipredator behaviors in turkey vultures, particularly stimulus processing and response, might not be well tuned to vehicles approaching at speeds ≥90 kph. The possible inability of turkey vultures to react appropriately to high-speed vehicles could be common among birds, and might represent an important determinant of bird-vehicle collisions. PMID:24503622

  5. Advancing migratory bird conservation and management by using radar: An interagency collaboration

    Science.gov (United States)

    Ruth, Janet M.; Barrow, Wylie C.; Sojda, Richard S.; Dawson, Deanna K.; Diehl, Robert H.; Manville, Albert; Green, Michael T.; Krueper, David J.; Johnston, Scott

    2005-01-01

    Migratory birds face many changes to the landscapes they traverse and the habitats they use. Wind turbines and communications towers, which pose hazards to birds and bats in flight, are being erected or proposed across the United States and offshore. Human activities can also destroy or threaten habitats critical to birds during migratory passage, and climate change appears to be altering migratory patterns. The U.S. Fish and Wildlife Service (USFWS) and other agencies are under increasing pressure to identify and evaluate movement patterns and habitats used during migration and other times.

  6. Soaring migratory birds avoid wind farm in the Isthmus of Tehuantepec, southern Mexico.

    Directory of Open Access Journals (Sweden)

    Rafael Villegas-Patraca

    Full Text Available The number of wind farms operating in the Isthmus of Tehuantepec, southern Mexico, has rapidly increased in recent years; yet, this region serves as a major migration route for various soaring birds, including Turkey Vultures (Cathartes aura and Swainson's Hawks (Buteo swainsoni. We analyzed the flight trajectories of soaring migrant birds passing the La Venta II wind farm during the two migratory seasons of 2011, to determine whether an avoidance pattern existed or not. We recorded three polar coordinates for the flight path of migrating soaring birds that were detected using marine radar, plotted the flight trajectories and estimated the number of trajectories that intersected the polygon defined by the wind turbines of La Venta II. Finally, we estimated the actual number of intersections per kilometer and compared this value with the null distributions obtained by running 10,000 simulations of our datasets. The observed number of intersections per kilometer fell within or beyond the lower end of the null distributions in the five models proposed for the fall season and in three of the four models proposed for the spring season. Flight trajectories had a non-random distribution around La Venta II, suggesting a strong avoidance pattern during fall and a possible avoidance pattern during spring. We suggest that a nearby ridgeline plays an important role in this pattern, an issue that may be incorporated into strategies to minimize the potential negative impacts of future wind farms on soaring birds. Studies evaluating these issues in the Isthmus of Tehuantepec have not been previously published; hence this work contributes important baseline information about the movement patterns of soaring birds and its relationship to wind farms in the region.

  7. Soaring Migratory Birds Avoid Wind Farm in the Isthmus of Tehuantepec, Southern Mexico

    Science.gov (United States)

    Villegas-Patraca, Rafael; Cabrera-Cruz, Sergio A.; Herrera-Alsina, Leonel

    2014-01-01

    The number of wind farms operating in the Isthmus of Tehuantepec, southern Mexico, has rapidly increased in recent years; yet, this region serves as a major migration route for various soaring birds, including Turkey Vultures (Cathartes aura) and Swainson's Hawks (Buteo swainsoni). We analyzed the flight trajectories of soaring migrant birds passing the La Venta II wind farm during the two migratory seasons of 2011, to determine whether an avoidance pattern existed or not. We recorded three polar coordinates for the flight path of migrating soaring birds that were detected using marine radar, plotted the flight trajectories and estimated the number of trajectories that intersected the polygon defined by the wind turbines of La Venta II. Finally, we estimated the actual number of intersections per kilometer and compared this value with the null distributions obtained by running 10,000 simulations of our datasets. The observed number of intersections per kilometer fell within or beyond the lower end of the null distributions in the five models proposed for the fall season and in three of the four models proposed for the spring season. Flight trajectories had a non-random distribution around La Venta II, suggesting a strong avoidance pattern during fall and a possible avoidance pattern during spring. We suggest that a nearby ridgeline plays an important role in this pattern, an issue that may be incorporated into strategies to minimize the potential negative impacts of future wind farms on soaring birds. Studies evaluating these issues in the Isthmus of Tehuantepec have not been previously published; hence this work contributes important baseline information about the movement patterns of soaring birds and its relationship to wind farms in the region. PMID:24647442

  8. Flight performance of western sandpipers, Calidris mauri, remains uncompromised when mounting an acute phase immune response.

    Science.gov (United States)

    Nebel, Silke; Buehler, Deborah M; MacMillan, Alexander; Guglielmo, Christopher G

    2013-07-15

    Migratory birds have been implicated in the spread of some zoonotic diseases, but how well infected individuals can fly remains poorly understood. We used western sandpipers, Calidris mauri, to experimentally test whether flight is affected when long-distance migrants are mounting an immune response and whether migrants maintain immune defences during a flight in a wind tunnel. We measured five indicators of innate immunity in 'flown-healthy' birds (flying in a wind tunnel without mounting an immune response), 'flown-sick' birds (flying while mounting an acute phase response, which is part of induced innate immunity), and a non-flying control group ('not-flown'). Voluntary flight duration did not differ between flown-healthy and flown-sick birds, indicating that mounting an acute phase response to simulated infection did not hamper an individual's ability to fly for up to 3 h. However, in comparison to not-flown birds, bacterial killing ability of plasma was significantly reduced after flight in flown-sick birds. In flown-healthy birds, voluntary flight duration was positively correlated with bacterial killing ability and baseline haptoglobin concentration of the blood plasma measured 1-3 weeks before experimental flights, suggesting that high quality birds had strong immune systems and greater flight capacity. Our findings indicate that flight performance is not diminished by prior immune challenge, but that flight while mounting an acute phase response negatively affects other aspects of immune function. These findings have important implications for our understanding of the transmission of avian diseases, as they suggest that birds can still migrate while fighting an infection.

  9. Potential impacts of wind turbines on birds at North Cape, Prince Edward Island

    Energy Technology Data Exchange (ETDEWEB)

    Kingsley, A.; Whitman, B.

    2001-12-13

    As the number of new wind power generating stations in Canada grows, so do concerns regarding the environmental impact of turbines on birds, particularly on raptors and migrating songbirds. These birds are generally at greatest risk of injury or death from turbines, but the impact of these structures on all bird species must be considered on a site-by-site basis. Disturbance to breeding and wintering as a result of turbines must be better researched. This report reviews the literature on the effects of wind turbines on birds, with reference to the North Cape, Prince Edward Island. It recommends ways to reduce potential impacts of turbines on birds in that area, and suggests a program whereby the potential effects of wind turbines on birds can be monitored. The bird groups likely to be seen at North Cape include water birds, raptors, songbirds, and 5 bird species that are considered to be provincially rare. The main causes of bird mortality at wind powered energy facilities are birds flying into rotating turbine blades. Migrating birds are attracted to warning lights on the turbines and collide with the structures and they also collide with the power lines connected to the station. Poor weather conditions, such as fog, increase the occurrence of collisions with towers. Several studies have shown that most migrating and wintering bird species alter their flight paths to avoid turbines. Studies also indicate that bird mortalities at wind energy facilities are not biologically significant and that impacts are not likely to be significant if wind turbines are located in areas of poor habitat and low bird densities. 61 refs., 1 tab., 1 fig.

  10. Soft-tissue and dermal arrangement in the wing of an Early Cretaceous bird: Implications for the evolution of avian flight

    Science.gov (United States)

    Navalón, Guillermo; Marugán-Lobón, Jesús; Chiappe, Luis M.; Luis Sanz, José; Buscalioni, Ángela D.

    2015-01-01

    Despite a wealth of fossils of Mesozoic birds revealing evidence of plumage and other soft-tissue structures, the epidermal and dermal anatomy of their wing’s patagia remain largely unknown. We describe a distal forelimb of an enantiornithine bird from the Lower Cretaceous limestones of Las Hoyas, Spain, which reveals the overall morphology of the integument of the wing and other connective structures associated with the insertion of flight feathers. The integumentary anatomy, and myological and arthrological organization of the new fossil is remarkably similar to that of modern birds, in which a system of small muscles, tendons and ligaments attaches to the follicles of the remigial feathers and maintains the functional integrity of the wing during flight. The new fossil documents the oldest known occurrence of connective tissues in association with the flight feathers of birds. Furthermore, the presence of an essentially modern connective arrangement in the wing of enantiornithines supports the interpretation of these primitive birds as competent fliers. PMID:26440221

  11. On the importance of radiative heat exchange during nocturnal flight in birds.

    Science.gov (United States)

    Léger, Jérôme; Larochelle, Jacques

    2006-01-01

    Many migratory flights take place during cloudless nights, thus under conditions where the sky temperature can commonly be 20 degrees C below local air temperature. The sky then acts as a radiative sink, leading objects exposed to it to have a lower surface temperature than unexposed ones because less infrared energy is received from the sky than from the surfaces that are isothermic to air. To investigate the significance of this effect for heat dissipation during nocturnal flight in birds, we built a wind tunnel with the facility to control wall temperature (TASK) and air temperature (TAIR) independently at air speeds (UWIN) comparable to flying speeds. We used it to measure the influence of TASK, TAIR and UWIN on plumage and skin temperatures in pigeons having to dissipate a thermal load while constrained at rest in a flight posture. Our results show that the temperature of the flight and insulation plumages exposed to a radiative sink can be accurately described by multiple regression models (r2>0.96) based only on TAIR, TASK and UWIN. Predictions based on these models indicate that while convection dominates heat loss for a plumage exposed to air moving at flight speed in a thermally uniform environment, radiation may dominate in the presence of a radiative sink comparable to a clear sky. Our data also indicate that reducing TASK to a temperature 20 degrees C below TAIR can increase the temperature difference across the exposed plumage by at least 13% and thus facilitate heat flow through the main thermal resistance to the loss of internally produced heat in birds. While extrapolation from our experimentally constrained conditions to free flight in the atmosphere is difficult, our results suggest that the sky temperature has been a neglected factor in determining the range of TAIR over which prolonged flight is possible.

  12. Do migratory birds need a nap after a long non-stop flight?

    NARCIS (Netherlands)

    Schwilch, R; Piersma, T; Holmgren, NMA; Jenni, L

    2002-01-01

    After a prolonged period of sleep deprivation, the urge to sleep overrules all other activities. Despite this well-known fact, the occurrence of sleep after naturally occurring sleep deprivation during long non-stop migratory flight in birds has hardly been investigated. The aim of this

  13. Bird Migration Under Climate Change - A Mechanistic Approach Using Remote Sensing

    Science.gov (United States)

    Smith, James A.; Blattner, Tim; Messmer, Peter

    2010-01-01

    The broad-scale reductions and shifts that may be expected under climate change in the availability and quality of stopover habitat for long-distance migrants is an area of increasing concern for conservation biologists. Researchers generally have taken two broad approaches to the modeling of migration behaviour to understand the impact of these changes on migratory bird populations. These include models based on causal processes and their response to environmental stimulation, "mechanistic models", or models that primarily are based on observed animal distribution patterns and the correlation of these patterns with environmental variables, i.e. "data driven" models. Investigators have applied the latter technique to forecast changes in migration patterns with changes in the environment, for example, as might be expected under climate change, by forecasting how the underlying environmental data layers upon which the relationships are built will change over time. The learned geostatstical correlations are then applied to the modified data layers.. However, this is problematic. Even if the projections of how the underlying data layers will change are correct, it is not evident that the statistical relationships will remain the same, i.e. that the animal organism may not adapt its' behaviour to the changing conditions. Mechanistic models that explicitly take into account the physical, biological, and behaviour responses of an organism as well as the underlying changes in the landscape offer an alternative to address these shortcomings. The availability of satellite remote sensing observations at multiple spatial and temporal scales, coupled with advances in climate modeling and information technologies enable the application of the mechanistic models to predict how continental bird migration patterns may change in response to environmental change. In earlier work, we simulated the impact of effects of wetland loss and inter-annual variability on the fitness of

  14. Impact of climate change effecting Decline on Migration Birds of Bhadalwadi Lake Indapur Taluka M.S India

    OpenAIRE

    U.S .Gantaloo; Sangeeta B Dongare

    2016-01-01

    Environmental changes are now a day’s happening regularly day to day increase in temperature ,Scarcity of rainfall ,Drying of lakes have strong implication on Biodiversity .) .Global warming has set in motion and is affecting the timing of migration of birds .Birds are reliable indicator of environment change for centuries and their arrival indicate start of winter and departure summer in study area .There are many example of the effect of climate change on birds from all around t...

  15. Low level exposure to crude oil impacts avian flight performance: The Deepwater Horizon oil spill effect on migratory birds.

    Science.gov (United States)

    Perez, Cristina R; Moye, John K; Cacela, Dave; Dean, Karen M; Pritsos, Chris A

    2017-12-01

    In 2010, the Deepwater Horizon oil spill released 134 million gallons of crude oil into the Gulf of Mexico making it the largest oil spill in US history. The three month oil spill left tens of thousands of birds dead; however, the fate of tens of thousands of other migratory birds that were affected but did not immediately die is unknown. We used the homing pigeon as a surrogate species for migratory birds to investigate the effects of a single external oiling event on the flight performance of birds. Data from GPS data loggers revealed that lightly oiled pigeons took significantly longer to return home and spent more time stopped en route than unoiled birds. This suggests that migratory birds affected by the oil spill could have experienced long term flight impairment and delayed arrival to breeding, wintering, or crucial stopover sites and subsequently suffered reductions in survival and reproductive success. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Migrating swans profit from favourable changes in wind conditions at low altitude

    NARCIS (Netherlands)

    Klaassen, M; Beekman, JH; Kontiokorpi, J; Mulder, RJW; Nolet, BA

    Because energy reserves limit flight range, wind assistance may be of crucial importance for migratory birds. We tracked eight Bewick's swans Cygnus columbianus bewickii, using 95-g satellite transmitters with altimeters and activity sensors, during their spring migration from Denmark to northern

  17. Migrating swans profit from favourable changes in wind conditions at low altitude

    NARCIS (Netherlands)

    Klaassen, M.R.J.; Beekman, J.H.; Kontiokorpi, J.; Mulder, R.J.W.; Nolet, B.A.

    2004-01-01

    Because energy reserves limit flight range, wind assistance may be of crucial importance for migratory birds. We tracked eight Bewicks swans Cygnus columbianus bewickii, using 95-g satellite transmitters with altimeters and activity sensors, during their spring migration from Denmark to northern

  18. Movement ecology of migration in turkey vultures.

    Science.gov (United States)

    Mandel, J T; Bildstein, K L; Bohrer, G; Winkler, D W

    2008-12-09

    We develop individual-based movement ecology models (MEM) to explore turkey vulture (Cathartes aura) migration decisions at both hourly and daily scales. Vulture movements in 10 migration events were recorded with satellite-reporting GPS sensors, and flight behavior was observed visually, aided by on-the-ground VHF radio-tracking. We used the North American Regional Reanalysis dataset to obtain values for wind speed, turbulent kinetic energy (TKE), and cloud height and used a digital elevation model for a measure of terrain ruggedness. A turkey vulture fitted with a heart-rate logger during 124 h of flight during 38 contiguous days showed only a small increase in mean heart rate as distance traveled per day increased, which suggests that, unlike flapping, soaring flight does not lead to greatly increased metabolic costs. Data from 10 migrations for 724 hourly segments and 152 daily segments showed that vultures depended heavily upon high levels of TKE in the atmospheric boundary layer to increase flight distances and maintain preferred bearings at both hourly and daily scales. We suggest how the MEM can be extended to other spatial and temporal scales of avian migration. Our success in relating model-derived atmospheric variables to migration indicates the potential of using regional reanalysis data, as here, and potentially other regional, higher-resolution, atmospheric models in predicting changing movement patterns of soaring birds under various scenarios of climate and land use change.

  19. Ecology of tern flight in relation to wind, topography and aerodynamic theory.

    Science.gov (United States)

    Hedenström, Anders; Åkesson, Susanne

    2016-09-26

    Flight is an economical mode of locomotion, because it is both fast and relatively cheap per unit of distance, enabling birds to migrate long distances and obtain food over large areas. The power required to fly follows a U-shaped function in relation to airspeed, from which context dependent 'optimal' flight speeds can be derived. Crosswinds will displace birds away from their intended track unless they make compensatory adjustments of heading and airspeed. We report on flight track measurements in five geometrically similar tern species ranging one magnitude in body mass, from both migration and the breeding season at the island of Öland in the Baltic Sea. When leaving the southern point of Öland, migrating Arctic and common terns made a 60° shift in track direction, probably guided by a distant landmark. Terns adjusted both airspeed and heading in relation to tail and side wind, where coastlines facilitated compensation. Airspeed also depended on ecological context (searching versus not searching for food), and it increased with flock size. Species-specific maximum range speed agreed with predicted speeds from a new aerodynamic theory. Our study shows that the selection of airspeed is a behavioural trait that depended on a complex blend of internal and external factors.This article is part of the themed issue 'Moving in a moving medium: new perspectives on flight'. © 2016 The Author(s).

  20. Partners in flight bird conservation plan for the Upper Great Lakes Plain (Physiographic Area 16)

    Science.gov (United States)

    Knutson, M.G.; Butcher, G.; Fitzgerald, J.; Shieldcastle, J.

    2001-01-01

    1 November 2001. Conservation of bird habitats is a major focus of effort by Partners in Flight, an international coalition of agencies, citizens, and other groups dedicated to 'keeping common birds common'. USGS worked on a planning team to publish a bird conservation plan for the Upper Great Lakes Plain ecoregion (PIF 16), which includes large portions of southern Wisconsin, southern Michigan and parts of Minnesota, Iowa, Illinois, Indiana, and Ohio. The conservation plan outlines specific habitat restoration and bird population objectives for the ecoregion over the next decade. The plan provides a context for on-the-ground conservation implementation by the US Fish and Wildlife Service, the USDA Natural Resources Conservation Service, the US Forest Service, states, and conservation groups. Citation: Knutson, M. G., G. Butcher, J. Fitzgerald, and J. Shieldcastle. 2001. Partners in Flight Bird Conservation Plan for The Upper Great Lakes Plain (Physiographic Area 16). USGS Upper Midwest Environmental Sciences Center in cooperation with Partners in Flight, La Crosse, Wisconsin. Download from website: http://www.blm.gov/wildlife/pifplans.htm. The Upper Great Lakes Plain covers the southern half of Michigan, northwest Ohio, northern Indiana, northern Illinois, southern Wisconsin, and small portions of southwest Minnesota and northwest Iowa. Glacial moraines and dissected plateaus are characteristic of the topography. Broadleaf forests, oak savannahs, and a variety of prairie communities are the natural vegetation types. A oDriftless Areao was not glaciated during the late Pleistocene and emerged as a unique area of great biological diversity. Priority bird species for the area include the Henslow's Sparrow, Sedge Wren, Bobolink, Golden-winged Warbler, Cerulean Warbler, Black-billed Cuckoo, and Red-headed Woodpecker. There are many large urban centers in this area whose growth and sprawl will continue to consume land. The vast majority of the presettlement forest and

  1. Bird and chiroptera inventories in Quebec : efficiency of a tried and tested method; Les inventaires d'oiseaux et de chiropteres au Quebec : l'efficacite d'une methode eprouvee

    Energy Technology Data Exchange (ETDEWEB)

    Castonguay, M. [Pesca Environnement, Maria, PQ (Canada)

    2007-07-01

    Environmental monitoring at wind turbine arrays is needed before, during and after project development. Pesca Environmental evaluates the impact of proposed wind turbine arrays on birds and chiroptera by examining their migration patterns through visual and auditory observations during the springtime reproductive and nesting season as well as in the autumn. In order to complete a feasibility study, spring migration patterns of birds and chiroptera must be documented and characterized. In addition to building an inventory of birds and chiroptera, Pesca examines bird behaviour and flight patterns and nesting locations. figs.

  2. Why do some, but not all, tropical birds migrate? A comparative study of diet breadth and fruit preference

    Science.gov (United States)

    Boyle, W.A.; Conway, C.J.; Bronstein, Judith L.

    2011-01-01

    Annual migrations of birds profoundly influence terrestrial communities. However, few empirical studies examine why birds migrate, in part due to the difficulty of testing causal hypotheses in long-distance migration systems. Short-distance altitudinal migrations provide relatively tractable systems in which to test explanations for migration. Many past studies explain tropical altitudinal migration as a response to spatial and temporal variation in fruit availability. Yet this hypothesis fails to explain why some coexisting, closely-related frugivorous birds remain resident year-round. We take a mechanistic approach by proposing and evaluating two hypotheses (one based on competitive exclusion and the other based on differences in dietary specialization) to explain why some, but not all, tropical frugivores migrate. We tested predictions of these hypotheses by comparing diets, fruit preferences, and the relationships between diet and preference in closely-related pairs of migrant and resident species. Fecal samples and experimental choice trials revealed that sympatric migrants and residents differed in both their diets and fruit preferences. Migrants consumed a greater diversity of fruits and fewer arthropods than did their resident counterparts. Migrants also tended to have slightly stronger fruit preferences than residents. Most critically, diets of migrants more closely matched their preferences than did the diets of residents. These results suggest that migrants may be competitively superior foragers for fruit compared to residents (rather than vice versa), implying that current competitive interactions are unlikely to explain variation in migratory behavior among coexisting frugivores. We found some support for the dietary specialization hypothesis, propose refinements to the mechanism underlying this hypothesis, and discuss how dietary specialization might ultimately reflect past interspecific competition. We recommend that future studies quantify variation

  3. The paradox of Spoonbill migration : Most birds travel to where survival rates are lowest

    NARCIS (Netherlands)

    Lok, Tamar; Overdijk, Otto; Tinbergen, Joost M.; Piersma, Theunis

    2011-01-01

    Migrant birds face a choice where to spend the winter. Presumably there is a trade-off between migration distance (costs) and the quality of the wintering site (benefits). Wintering site fidelity is often high and increases with age. Hypotheses to explain such a pattern assume that wintering site

  4. Extreme endurance flights by landbirds crossing the Pacific Ocean: Ecological corridor rather than barrier?

    Science.gov (United States)

    Gill, Robert E.; Tibbitts, T.L.; Douglas, David C.; Handel, Colleen M.; Mulcahy, D.M.; Gottschalck, J.C.; Warnock, N.; McCaffery, B.J.; Battley, Phil F.; Piersma, Theunis

    2009-01-01

    Mountain ranges, deserts, ice fields and oceans generally act as barriers to the movement of land-dependent animals, often profoundly shaping migration routes. We used satellite telemetry to track the southward flights of bar-tailed godwits (Limosa lapponica baueri), shorebirds whose breeding and non-breeding areas are separated by the vast central Pacific Ocean. Seven females with surgically implanted transmitters flew non-stop 8117-11680km (10153??1043 s.d.) directly across the Pacific Ocean; two males with external transmitters flew non-stop along the same corridor for 7008-7390km. Flight duration ranged from 6.0 to 9.4 days (7.8??1.3 s.d.) for birds with implants and 5.0 to 6.6 days for birds with externally attached transmitters. These extraordinary non-stop flights establish new extremes for avian flight performance, have profound implications for understanding the physiological capabilities of vertebrates and how birds navigate, and challenge current physiological paradigms on topics such as sleep, dehydration and phenotypic flexibility. Predicted changes in climatic systems may affect survival rates if weather conditions at their departure hub or along the migration corridor should change. We propose that this transoceanic route may function as an ecological corridor rather than a barrier, providing a wind-assisted passage relatively free of pathogens and predators. ?? 2008 The Royal Society.

  5. BIRDS’ FLIGHT ENERGY PREDICTIONS AND APPLICATION TO RADAR-TRACKING STUDY

    Directory of Open Access Journals (Sweden)

    Matsyura Alex

    2013-12-01

    Full Text Available In ofered research, we propose to observe diurnal soaring birds to check, whether there the positions of birds in formations are such, that the wing tip interval and depth met the predictions of aerodynamic theory for achievement of maximal conservation of energy or predictions of the hypothesis of communication. We also can estimate, whether adverse conditions of a wind influence the abilty of birds to support formation. We can asume that windy conditions during flight might make precision flight more dificult by inducing both unpredictable bird and vortex positions. To this, we ned to found change in wing-tip spacing variation with increasing wind sped, sugesting or rejecting that in high winds bird skeins maintained similar variation to that on calm days. The interelation betwen variation of mean depth and wind sped should prove this hypothesis. Litle is known about the importance of depth, but in high winds the vortex is likely to break up more rapidly and its location become unpredictable the further back a bird flies; therefore, a shift towards skeins with more regular depths at high wind speds may compensate for the unpredictabilty of the vortex locations. Any significant relationship betwen the standard deviation of wing-tip spacing and wind sped sugests that wind has a major efect on optimal positioning. Results of proposed study wil be used also as the auxilary tol in radar research of bird migration, namely in research of flight features of soaring birds. It is extremely important to determine al pertinent characteristics of flock for model species, namely flocking birds

  6. Birds of Two Oceans? Trans-Andean and Divergent Migration of Black Skimmers (Rynchops niger cinerascens) from the Peruvian Amazon.

    Science.gov (United States)

    Davenport, Lisa C; Goodenough, Katharine S; Haugaasen, Torbjørn

    2016-01-01

    Seasonal flooding compels some birds that breed in aquatic habitats in Amazonia to undertake annual migrations, yet we know little about how the complex landscape of the Amazon region is used seasonally by these species. The possibility of trans-Andes migration for Amazonian breeding birds has largely been discounted given the high geographic barrier posed by the Andean Cordillera and the desert habitat along much of the Pacific Coast. Here we demonstrate a trans-Andes route for Black Skimmers (Rynchops niger cinerascens) breeding on the Manu River (in the lowlands of Manu National Park, Perú), as well as divergent movement patterns both regionally and across the continent. Of eight skimmers tracked with satellite telemetry, three provided data on their outbound migrations, with two crossing the high Peruvian Andes to the Pacific. A third traveled over 1800 km to the southeast before transmissions ended in eastern Paraguay. One of the two trans-Andean migrants demonstrated a full round-trip migration back to its tagging location after traveling down the Pacific Coast from latitude 9° South to latitude 37° S, spending the austral summer in the Gulf of Arauco, Chile. This is the first documentation of a trans-Andes migration observed for any bird breeding in lowland Amazonia. To our knowledge, this research also documents the first example of a tropical-breeding waterbird migrating out of the tropics to spend the non-breeding season in the temperate summer, this being the reverse pattern with respect to seasonality for austral migrants in general.

  7. Flying, fasting, and feeding in birds during migration: a nutritional and physiological ecology perspective

    NARCIS (Netherlands)

    McWilliams, S.R.; Guglielmo, C.; Pierce, B.; Klaassen, M.R.J.

    2004-01-01

    Unlike exercising mammals, migratory birds fuel very high intensity exercise (e.g., flight) with fatty acids delivered from the adipose tissue to the working muscles by the circulatory system. Given the primary importance of fatty acids for fueling intense exercise, we discuss the likely limiting

  8. Metabolic profile of long-distance migratory flight and stopover in a shorebird

    NARCIS (Netherlands)

    Landys, MM; Piersma, T; Guglielmo, CG; Jukema, J; Ramenofsky, M; Wingfield, JC; Guglielmo, Christopher G.; Wingfield, John C.

    2005-01-01

    Migrating birds often complete long non-stop flights during which body energy stores exclusively support energetic demands. The metabolic correlates of such long-distance travel in free-living migrants are as yet poorly studied. Bar-tailed godwits, Limosa lapponica taymyrensis, undertake a 4500 km

  9. Viability of long range dragonfly migration across the Indian Ocean: An energetics perspective

    Science.gov (United States)

    Saha, Sandeep; Nirwal, Satvik

    2016-11-01

    Recently Pantala flavescens (dragonflies) have been reported to migrate in millions from India to Eastern Africa on a multigenerational migratory circuit of length 14000-18000 kms. We attempt to understand the ability of dragonflies to perform long range migration by examining the energetics using computer simulations. In absence of a theory for long range insect migrations, we resort to the extensive literature on long range bird migration from the energetics perspective. The flight energetics depends upon instantaneous power and velocity. The mechanical flight power is computed from the power curve which is then converted to mass depletion using Brequet's equation. However, the mechanical flight power itself depends upon the instantaneous velocity which can vary depending upon the current mass. In order to predict the range in our simulations, we assume that the insect progressively tries to achieve the maximum range velocity. The results indicate that the migration range is approximately 1260 kms in 70 hours based on the true airspeed. However, our analysis is restricted by the lack of data and certain caveats in drag prediction and basal metabolism rate.

  10. Understanding how birds navigate

    DEFF Research Database (Denmark)

    Solov'yov, Ilia; Schulten, Klaus

    2009-01-01

    A proposed model for migrating birds' magnetic sense can withstand moderate orientational disorder of a key protein in the eye.......A proposed model for migrating birds' magnetic sense can withstand moderate orientational disorder of a key protein in the eye....

  11. Matching times of leading and following suggest cooperation through direct reciprocity during V-formation flight in ibis.

    Science.gov (United States)

    Voelkl, Bernhard; Portugal, Steven J; Unsöld, Markus; Usherwood, James R; Wilson, Alan M; Fritz, Johannes

    2015-02-17

    One conspicuous feature of several larger bird species is their annual migration in V-shaped or echelon formation. When birds are flying in these formations, energy savings can be achieved by using the aerodynamic up-wash produced by the preceding bird. As the leading bird in a formation cannot profit from this up-wash, a social dilemma arises around the question of who is going to fly in front? To investigate how this dilemma is solved, we studied the flight behavior of a flock of juvenile Northern bald ibis (Geronticus eremita) during a human-guided autumn migration. We could show that the amount of time a bird is leading a formation is strongly correlated with the time it can itself profit from flying in the wake of another bird. On the dyadic level, birds match the time they spend in the wake of each other by frequent pairwise switches of the leading position. Taken together, these results suggest that bald ibis cooperate by directly taking turns in leading a formation. On the proximate level, we propose that it is mainly the high number of iterations and the immediacy of reciprocation opportunities that favor direct reciprocation. Finally, we found evidence that the animals' propensity to reciprocate in leading has a substantial influence on the size and cohesion of the flight formations.

  12. Anatomy and histochemistry of hindlimb flight posture in birds. I. The extended hindlimb posture of shorebirds.

    Science.gov (United States)

    McFarland, Joshua C; Meyers, Ron A

    2008-08-01

    Birds utilize one of two hindlimb postures during flight: an extended posture (with the hip and knee joints flexed, while the ankle joint is extended caudally) or a flexed posture (with the hip, knee, and ankle joints flexed beneath the body). American Avocets (Recurvirostra americana) and Black-necked Stilts (Himantopus mexicanus) extend their legs caudally during flight and support them for extended periods. Slow tonic and slow twitch muscle fibers are typically found in muscles functioning in postural support due to the fatigue resistance of these fibers. We hypothesized that a set of small muscles composed of high percentages of slow fibers and thus dedicated to postural support would function in securing the legs in the extended posture during flight. This study examined the anatomy and histochemical profile of eleven hindlimb muscles to gain insight into their functional roles during flight. Contrary to our hypothesis, all muscles possessed both fast twitch and slow twitch or slow tonic fibers. We believe this finding is due to the versatility of dynamic and postural functions the leg muscles must facilitate, including standing, walking, running, swimming, and hindlimb support during flight. Whether birds use an extended or flexed hindlimb flight posture may be related to the aerodynamic effect of leg position or may reflect evolutionary history. (c) 2008 Wiley-Liss, Inc.

  13. The effect of the Sep wind park near Oosterbierum, Friesland, The Netherlands, on birds. De invloed van de Sep-proefwindcentrale te Oosterbierum (Friesland) op vogels; Deel 3: Aanvlieggedrag overdag

    Energy Technology Data Exchange (ETDEWEB)

    Winkelman, J E

    1992-01-01

    The study concerns 1984-1991. The wind park consists of 18 three-bladed 300 kW horizontal axis wind turbines of 35 meters height, and a rotor diameter of 30 meters, seven meteorological towers, and three cluster and control buildings. Aspects studied included disturbance of breeding, resting or feeding, and migrating birds, behavior of birds approaching the wind turbines during the day and night, and bird victims due to collision with the wind turbines and the meteorological towers. The flight behavior of birds approaching the wind park system during daylight is also dealt with. For at least a fifth of the observations it was noted whether the birds passing within 100 meters distance of a turbine showed a reaction or not. The proportion of the reactions was related to the wind park in operation or not in operation, and to the distance between the wind turbines, species, flight height, the passing distance, wind direction and wind force. Secondly the flight path of birds approaching the wind park from eastern directions during daylight (real autumn migration) and from southern directions during late afternoon (flights of gulls to night roosts) was studied in detail. Significantly more reactions (11-18%) were recorded with the wind park fully operational compared to the wind park not operational (2%). In total 2203 flight paths of birds approaching the wind park were recorded during 151 hours of observation. The test results showed that a passing distance of less or more than 100 meters of the nearest wind turbine did not affect the proportion of reactions. Several reaction types and combinations were noted, varying from gradual and calm reactions (circa 75%), and panic reactions, occurring just before or while passing the wind turbines. The reactions are shift in the flight path in the horizontal plane (30%), shift in the flight path in the vertical plane (14%), one passing attempt (87%), an accelerated wing beat (14%), an alteration of the angle of the body (21%).

  14. On the Transition and Migration of Flight Functions in the Airspace System

    Science.gov (United States)

    Morris, Allan Terry; Young, Steve D.

    2012-01-01

    Since 400 BC, when man first replicated flying behavior with kites, up until the turn of the 20th century, when the Wright brothers performed the first successful powered human flight, flight functions have become available to man via significant support from man-made structures and devices. Over the past 100 years or so, technology has enabled several flight functions to migrate to automation and/or decision support systems. This migration continues with the United States NextGen and Europe s Single European Sky (a.k.a. SESAR) initiatives. These overhauls of the airspace system will be accomplished by accommodating the functional capabilities, benefits, and limitations of technology and automation together with the unique and sometimes overlapping functional capabilities, benefits, and limitations of humans. This paper will discuss how a safe and effective migration of any flight function must consider several interrelated issues, including, for example, shared situation awareness, and automation addiction, or over-reliance on automation. A long-term philosophical perspective is presented that considers all of these issues by primarily asking the following questions: How does one find an acceptable level of risk tolerance when allocating functions to automation versus humans? How does one measure or predict with confidence what the risks will be? These two questions and others will be considered from the two most-discussed paradigms involving the use of increasingly complex systems in the future: humans as operators and humans as monitors.

  15. Influence of Riparian Tree Phenology on Lower Colorado River Spring-Migrating Birds: Implications of Flower Cueing

    Science.gov (United States)

    McGrath, Laura J.; van Riper, Charles

    2005-01-01

    Executive Summary Neotropical migrant birds make choices about which habitats are most likely to provide successful foraging locations during migration, but little is known about how these birds recognize and process environmental clues that indicate the presence of prey species. Aspects of tree phenology, notably flowering of trees along the lower Colorado River corridor, coincide with the migratory stopovers of leaf-gleaning insectivorous songbirds and may be an important indicator of arthropod prey species availability. Shifting tree flowering and leaf flush during the spring migration period presents avian insectivores with an assortment of foraging opportunities. During two field seasons at Cibola National Wildlife Refuge in southwestern Arizona, we examined riparian tree species to test whether leaf-gleaning insectivorous birds are attracted to the flowering condition of trees in choosing foraging sites. We predicted that flowering trees would host more insect prey resources, would thus show increased visit rates, length of stays and attack ratios of migrant avian insectivores, and that those arthropods would be found in the stomach contents of the birds. Paired trees of honey mesquite (Prosopis glandulosa), displaying heavy and light degrees of flowering were observed to test these predictions. To test whether birds are tracking arthropods directly or are using flowers as a proximate cue, we removed flowers from selected trees and paired these treated trees with neighboring high flowering trees, which served as controls. Avian foraging behavior, avian diets, arthropods, and phenology data were collected at the same time to control for temporal differences in insect availability, plant phenology, and differences in stopover arrivals of birds. We documented five patterns from this study: 1) Higher abundance and richness of arthropods were found on honey mesquite trees with greater numbers of flowers. 2) Arthropod abundance and richness increased as flowering

  16. Challenging a 15-year-old claim: The North Atlantic Oscillation index as a predictor of spring migration phenology of birds.

    Science.gov (United States)

    Haest, Birgen; Hüppop, Ommo; Bairlein, Franz

    2018-04-01

    Many migrant bird species that breed in the Northern Hemisphere show advancement in spring arrival dates. The North Atlantic Oscillation (NAO) index is one of the climatic variables that have been most often investigated and shown to be correlated with these changes in spring arrival. Although the NAO is often claimed to be a good predictor or even to have a marked effect on interannual changes in spring migration phenology of Northern Hemisphere breeding birds, the results on relations between spring migration phenology and NAO show a large variety, ranging from no, over weak, to a strong association. Several factors, such as geographic location, migration phase, and the NAO index time window, have been suggested to partly explain these observed differences in association. A combination of a literature meta-analysis, and a meta-analysis and sliding time window analysis of a dataset of 23 short- and long-distance migrants from the constant-effort trapping garden at Helgoland, Germany, however, paints a completely different picture. We found a statistically significant overall effect size of the NAO on spring migration phenology (coefficient = -0.14, SE = 0.054), but this on average only explains 0%-6% of the variance in spring migration phenology across all species. As such, the value and biological meaning of the NAO as a general predictor or explanatory variable for climate change effects on migration phenology of birds, seems highly questionable. We found little to no definite support for previously suggested factors, such as geographic location, migration phenology phase, or the NAO time window, to explain the heterogeneity in correlation differences. We, however, did find compelling evidence that the lack of accounting for trends in both time series has led to strongly inflated (spurious) correlations in many studies (coefficient = -0.13, SE = 0.019). © 2017 John Wiley & Sons Ltd.

  17. Flying with the wind: Scale dependency of speed and direction measurements in modelling wind support in avian flight

    Science.gov (United States)

    Safi, Kamran; Kranstauber, Bart; Weinzierl, Rolf P.; Griffin, Larry; Reese, Eileen C.; Cabot, David; Cruz, Sebastian; Proaño, Carolina; Takekawa, John Y.; Newman, Scott H.; Waldenström, Jonas; Bengtsson, Daniel; Kays, Roland; Wikelski, Martin; Bohrer, Gil

    2013-01-01

    Background: Understanding how environmental conditions, especially wind, influence birds' flight speeds is a prerequisite for understanding many important aspects of bird flight, including optimal migration strategies, navigation, and compensation for wind drift. Recent developments in tracking technology and the increased availability of data on large-scale weather patterns have made it possible to use path annotation to link the location of animals to environmental conditions such as wind speed and direction. However, there are various measures available for describing not only wind conditions but also the bird's flight direction and ground speed, and it is unclear which is best for determining the amount of wind support (the length of the wind vector in a bird’s flight direction) and the influence of cross-winds (the length of the wind vector perpendicular to a bird’s direction) throughout a bird's journey.Results: We compared relationships between cross-wind, wind support and bird movements, using path annotation derived from two different global weather reanalysis datasets and three different measures of direction and speed calculation for 288 individuals of nine bird species. Wind was a strong predictor of bird ground speed, explaining 10-66% of the variance, depending on species. Models using data from different weather sources gave qualitatively similar results; however, determining flight direction and speed from successive locations, even at short (15 min intervals), was inferior to using instantaneous GPS-based measures of speed and direction. Use of successive location data significantly underestimated the birds' ground and airspeed, and also resulted in mistaken associations between cross-winds, wind support, and their interactive effects, in relation to the birds' onward flight.Conclusions: Wind has strong effects on bird flight, and combining GPS technology with path annotation of weather variables allows us to quantify these effects for

  18. Weather and eared grebe winter migration near the Great Salt Lake, Utah

    Science.gov (United States)

    Williams, Augusta A.; Laird, Neil F.

    2018-03-01

    This study provides insight from the use of weather radar observations to understand the characteristics of the eared grebe migration near the Great Salt Lake (GSL) and provides unique information on weather conditions connected to these migration events. Doppler weather radar measurements from the Salt Lake City, Utah WSR-88D radar site (KMTX), along with meteorological surface and rawinsonde data, were used to identify and examine 281 eared grebe migration events across 15 winters from 1997/1998 through 2011/2012. An average of about 19 migration events occurred each winter with considerable interannual variability, as well as large variance in the spatial area and number of birds departing the GSL during each event. The migration events typically occurred during clear sky conditions in the presence of surface high pressure and colder than average surface temperatures. Migration events began 55 min after sunset, on average across the winter seasons, and in one case we demonstrate that an extended, nonstop flight was initiated of the departing eared grebes to northern Mexico. Eared grebes leaving the GSL largely flew above the freezing level with a mean northerly tailwind at flight altitude of 3.1 m s-1 and a westerly, cross-flight wind of 5.0 m s-1 while having an average flight speed at cruising altitude of 16.9 m s-1, or 61 km h-1. In addition to determining the variability of meteorological conditions during migration events across the 15 winters, atmospheric conditions during the largest migration event observed are presented and discussed.

  19. Observation of bird interaction with wind turbines : Canadian applications and challenges

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, J.; Brown, K.; Hamilton, B. [Vision Quest Windelectric Inc., Calgary, AB (Canada)

    2002-07-01

    An environmental study has been conducted on a wind farm adjacent to Castle River, in the foothills of the Rocky Mountains in Alberta, to determine the impact of wind turbines on birds. The wind farm includes a total of 60 turbines. The study consisted of 30 observation days between March and December 2001 during which time nearly 2000 birds were monitored. These included 27 different species, including 181 raptors, 1021 waterfowl, and 821 passerines. The observations focused on spring and fall migration of birds. The observations looked at bird numbers, location relative to turbines, and changes in flight pattern. The study found that raptors flew around or over the turbine blades, while passerines remained below, and waterfowl flew up and over the blades. In total, 4 dead birds were found over the 9 month period, which translates to 0.15 birds per turbine per year. This study demonstrates that there are few bird fatalities associated with wind turbines, therefore it was concluded that wind turbines do not have a major impact on birds. The results of this study are consistent with international studies. 2 figs.

  20. Saving our shared birds: Partners in Flight tri-national vision for landbird conservation

    Science.gov (United States)

    Berlanga, Humberto; Kennedy, Judith A.; Rich, Terrell D.; Arizmendi, Maria del Coro; Beardmore, Carol J.; Blancher, Peter J.; Butcher, Gregory S.; Couturier, Andrew R.; Dayer, Ashley A.; Demarest, Dean W.; Easton, Wendy E.; Gustafson, Mary; Iñigo-Elias, Eduardo E.; Krebs, Elizabeth A.; Panjabi, Arvind O.; Rodriguez Contreras, Vicente; Rosenberg, Kenneth V.; Ruth, Janet M.; Santana Castellon, Eduardo; Vidal, Rosa Ma.; Will, Tom

    2010-01-01

    Landbirds are the most abundant and diverse group of birds in North America, with nearly 900 species distributed across every major terrestrial habitat. Birds are indicators of environmental health; their populations track changes in habitat, water, disease, and climate. They are providers of invaluable ecosystem services, such as pest control, seed dispersal, and pollination. As the focus of bird watching, they help generate billions of dollars for national economies. Yet, we are in danger of losing this spectacular and irreplaceable bird diversity: landbirds are experiencing significant declines, ominous threats, and shrinking habitats across a continent with growing human populations, increasing resource consumption, and changing climate. Saving Our Shared Birds presents for the first time a comprehensive conservation assessment of landbirds in Canada, Mexico, and the continental United States. This new tri-national vision encompasses the complete range of many migratory species and highlights the vital links among migrants and highly threatened resident species in Mexico. It points to a set of continent-scale actions necessary to maintain the landbird diversity and abundance that are our shared responsibility. This collaborative effort of Partners in Flight (PIF) is the next step in linking the countries of the Western Hemisphere to help species at risk and keep common birds common through voluntary partnerships—our mission since 1990. Saving Our Shared Birds builds upon PIF’s 2004 North American Landbird Conservation Plan, which presented science-based priorities for the conservation of 448 landbird species in Canada and the United States. Our three nations have expressed their commitment to cooperative conservation through numerous international treaties, agreements, and programs, including formation of the North American Bird Conservation Initiative (NABCI) a decade ago. The NABCI partnership recognizes that effective conservation requires a concerted

  1. The evolution of high summit metabolism and cold tolerance in birds and its impact on present-day distributions.

    Science.gov (United States)

    Swanson, David L; Garland, Theodore

    2009-01-01

    Summit metabolic rate (M(sum), maximum cold-induced metabolic rate) is positively correlated with cold tolerance in birds, suggesting that high M(sum) is important for residency in cold climates. However, the phylogenetic distribution of high M(sum) among birds and the impact of its evolution on current distributions are not well understood. Two potential adaptive hypotheses might explain the phylogenetic distribution of high M(sum) among birds. The cold adaptation hypothesis contends that species wintering in cold climates should have higher M(sum) than species wintering in warmer climates. The flight adaptation hypothesis suggests that volant birds might be capable of generating high M(sum) as a byproduct of their muscular capacity for flight; thus, variation in M(sum) should be associated with capacity for sustained flight, one indicator of which is migration. We collected M(sum) data from the literature for 44 bird species and conducted both conventional and phylogenetically informed statistical analyses to examine the predictors of M(sum) variation. Significant phylogenetic signal was present for log body mass, log mass-adjusted M(sum), and average temperature in the winter range. In multiple regression models, log body mass, winter temperature, and clade were significant predictors of log M(sum). These results are consistent with a role for climate in determining M(sum) in birds, but also indicate that phylogenetic signal remains even after accounting for associations indicative of adaptation to winter temperature. Migratory strategy was never a significant predictor of log M(sum) in multiple regressions, a result that is not consistent with the flight adaptation hypothesis.

  2. Weather and eared grebe winter migration near the Great Salt Lake, Utah.

    Science.gov (United States)

    Williams, Augusta A; Laird, Neil F

    2018-03-01

    This study provides insight from the use of weather radar observations to understand the characteristics of the eared grebe migration near the Great Salt Lake (GSL) and provides unique information on weather conditions connected to these migration events. Doppler weather radar measurements from the Salt Lake City, Utah WSR-88D radar site (KMTX), along with meteorological surface and rawinsonde data, were used to identify and examine 281 eared grebe migration events across 15 winters from 1997/1998 through 2011/2012. An average of about 19 migration events occurred each winter with considerable interannual variability, as well as large variance in the spatial area and number of birds departing the GSL during each event. The migration events typically occurred during clear sky conditions in the presence of surface high pressure and colder than average surface temperatures. Migration events began 55 min after sunset, on average across the winter seasons, and in one case we demonstrate that an extended, nonstop flight was initiated of the departing eared grebes to northern Mexico. Eared grebes leaving the GSL largely flew above the freezing level with a mean northerly tailwind at flight altitude of 3.1 m s -1 and a westerly, cross-flight wind of 5.0 m s -1 while having an average flight speed at cruising altitude of 16.9 m s -1 , or 61 km h -1 . In addition to determining the variability of meteorological conditions during migration events across the 15 winters, atmospheric conditions during the largest migration event observed are presented and discussed.

  3. Assessment of the Impacts of Green Mountain Power Corporation's Wind Power Facility on Breeding and Migrating Birds in Searsburg, Vermont: July 1996--July 1998

    Energy Technology Data Exchange (ETDEWEB)

    Kerlinger, P.

    2002-03-01

    A 6-megawatt, 11 turbine wind power development was constructed by Green Mountain Power Corporation in Searsburg, southern Vermont, in 1996. To determine whether birds were impacted, a series of modified BA (Before, After) studies was conducted before construction (1993-1996), during (1996), and after (1997) construction on the project site. The studies were designed to monitor changes in breeding bird community (species composition and abundance) on the site, examine the behavior and numbers of songbirds migrating at night over the site and hawks migrating over the site in daylight, and search for carcasses of birds that might have collided with the turbines.

  4. What Drives Bird Vision? Bill Control and Predator Detection Overshadow Flight

    Directory of Open Access Journals (Sweden)

    Graham R. Martin

    2017-11-01

    Full Text Available Although flight is regarded as a key behavior of birds this review argues that the perceptual demands for its control are met within constraints set by the perceptual demands of two other key tasks: the control of bill (or feet position, and the detection of food items/predators. Control of bill position, or of the feet when used in foraging, and timing of their arrival at a target, are based upon information derived from the optic flow-field in the binocular region that encompasses the bill. Flow-fields use information extracted from close to the bird using vision of relatively low spatial resolution. The detection of food items and predators is based upon information detected at a greater distance and depends upon regions in the retina with relatively high spatial resolution. The tasks of detecting predators and of placing the bill (or feet accurately, make contradictory demands upon vision and these have resulted in trade-offs in the form of visual fields and in the topography of retinal regions in which spatial resolution is enhanced, indicated by foveas, areas, and high ganglion cell densities. The informational function of binocular vision in birds does not lie in binocularity per se (i.e., two eyes receiving slightly different information simultaneously about the same objects but in the contralateral projection of the visual field of each eye. This ensures that each eye receives information from a symmetrically expanding optic flow-field centered close to the direction of the bill, and from this the crucial information of direction of travel and time-to-contact can be extracted, almost instantaneously. Interspecific comparisons of visual fields between closely related species have shown that small differences in foraging techniques can give rise to different perceptual challenges and these have resulted in differences in visual fields even within the same genus. This suggests that vision is subject to continuing and relatively rapid

  5. State-dependent sensorimotor processing: gaze and posture stability during simulated flight in birds.

    Science.gov (United States)

    McArthur, Kimberly L; Dickman, J David

    2011-04-01

    Vestibular responses play an important role in maintaining gaze and posture stability during rotational motion. Previous studies suggest that these responses are state dependent, their expression varying with the environmental and locomotor conditions of the animal. In this study, we simulated an ethologically relevant state in the laboratory to study state-dependent vestibular responses in birds. We used frontal airflow to simulate gliding flight and measured pigeons' eye, head, and tail responses to rotational motion in darkness, under both head-fixed and head-free conditions. We show that both eye and head response gains are significantly higher during flight, thus enhancing gaze and head-in-space stability. We also characterize state-specific tail responses to pitch and roll rotation that would help to maintain body-in-space orientation during flight. These results demonstrate that vestibular sensorimotor processing is not fixed but depends instead on the animal's behavioral state.

  6. Mapping global diversity patterns for migratory birds.

    Directory of Open Access Journals (Sweden)

    Marius Somveille

    Full Text Available Nearly one in five bird species has separate breeding and overwintering distributions, and the regular migrations of these species cause a substantial seasonal redistribution of avian diversity across the world. However, despite its ecological importance, bird migration has been largely ignored in studies of global avian biodiversity, with few studies having addressed it from a macroecological perspective. Here, we analyse a dataset on the global distribution of the world's birds in order to examine global spatial patterns in the diversity of migratory species, including: the seasonal variation in overall species diversity due to migration; the contribution of migratory birds to local bird diversity; and the distribution of narrow-range and threatened migratory birds. Our analyses reveal a striking asymmetry between the Northern and Southern hemispheres, evident in all of the patterns investigated. The highest migratory bird diversity was found in the Northern Hemisphere, with high inter-continental turnover in species composition between breeding and non-breeding seasons, and extensive regions (at high latitudes where migratory birds constitute the majority of the local avifauna. Threatened migratory birds are concentrated mainly in Central and Southern Asia, whereas narrow-range migratory species are mainly found in Central America, the Himalayas and Patagonia. Overall, global patterns in the diversity of migratory birds indicate that bird migration is mainly a Northern Hemisphere phenomenon. The asymmetry between the Northern and Southern hemispheres could not have easily been predicted from the combined results of regional scale studies, highlighting the importance of a global perspective.

  7. Landscape associations of birds during migratory stopover

    Science.gov (United States)

    Diehl, Robert Howard

    The challenge for migratory bird conservation is habitat preservation that sustains breeding, migration, and non-breeding biological processes. In choosing an appropriately scaled conservation arena for habitat preservation, a conservative and thorough examination of stopover habitat use patterns by migrants works back from the larger scales at which such relationships may occur. Because the use of stopover habitats by migrating birds occurs at spatial scales larger than traditional field techniques can easily accommodate, I quantify these relationship using the United States system of weather surveillance radars (popularly known as NEXRAD). To provide perspective on use of this system for biologists, I first describe the technical challenges as well as some of the biological potential of these radars for ornithological research. Using data from these radars, I then examined the influence of Lake Michigan and the distribution of woodland habitat on migrant concentrations in northeastern Illinois habitats during stopover. Lake Michigan exerted less influence on migrant abundance and density than the distribution and availability of habitat for stopover. There was evidence of post-migratory movement resulting in habitats within suburban landscapes experiencing higher migrant abundance but lower migrant density than habitats within nearby urban and agricultural landscapes. Finally, in the context of hierarchy theory, I examined the influence of landscape ecological and behavioral processes on bird density during migratory stopover. Migrant abundance did not vary across landscapes that differed considerably in the amount of habitat available for stopover. As a result, smaller, more isolated patches held higher densities of birds. Spatial models of migrant habitat selection based on migrant proximity to a patch explained nearly as much variance in the number of migrants occupying patches (R2 = 0.88) as selection models based on migrant interception of patches during

  8. Passive unmanned sky spectroscopy for remote bird classification

    Science.gov (United States)

    Lundin, Patrik; Brydegaard, Mikkel; Cocola, Lorenzo; Runemark, Anna; Åkesson, Susanne; Svanberg, Sune

    2011-11-01

    We present a method based on passive spectroscopy with aim to remotely study flying birds. A compact spectrometer is continuously recording spectra of a small section of the sky, waiting for birds to obscure part of the field-of-view when they pass the field in flight. In such situations the total light intensity received through the telescope, looking straight up, will change very rapidly as compared to the otherwise slowly varying sky light. On passage of a bird, both the total intensity and the spectral shape of the captured light changes notably. A camera aimed in the same direction as the telescope, although with a wider field-of-view, is triggered by the sudden intensity changes in the spectrometer to record additional information, which may be used for studies of migration and orientation. Example results from a trial are presented and discussed. The study is meant to explore the information that could be gathered and extracted with the help of a spectrometer connected to a telescope. Information regarding the color, size and height of flying birds is discussed. Specifically, an application for passive distance determination utilizing the atmospheric oxygen A-band absorption at around 760 nm is discussed.

  9. The Identification of Military Installations as Important Migratory Bird Stopover Sites and the Development of Bird Migration Forecast Models: A Radar Ornithology Approach

    Science.gov (United States)

    2012-08-01

    civilian and military flights. Since 1985, nearly 38,000 bird-military aircraft collisions have been reported. These collisions have killed 33 pilots...stations in the contiguous United States. Edges of the circles are at 124 nautical mile range (230 km). and 2004, approximately 194 people were killed ... Mockingbird Wilson’s Snipe Pileated Woodpecker American Wigeon Red-bellied Woodpecker American Coot Red-cockaded Woodpecker Black-crowned Night

  10. Predictable evolution toward flightlessness in volant island birds.

    Science.gov (United States)

    Wright, Natalie A; Steadman, David W; Witt, Christopher C

    2016-04-26

    Birds are prolific colonists of islands, where they readily evolve distinct forms. Identifying predictable, directional patterns of evolutionary change in island birds, however, has proved challenging. The "island rule" predicts that island species evolve toward intermediate sizes, but its general applicability to birds is questionable. However, convergent evolution has clearly occurred in the island bird lineages that have undergone transitions to secondary flightlessness, a process involving drastic reduction of the flight muscles and enlargement of the hindlimbs. Here, we investigated whether volant island bird populations tend to change shape in a way that converges subtly on the flightless form. We found that island bird species have evolved smaller flight muscles than their continental relatives. Furthermore, in 366 populations of Caribbean and Pacific birds, smaller flight muscles and longer legs evolved in response to increasing insularity and, strikingly, the scarcity of avian and mammalian predators. On smaller islands with fewer predators, birds exhibited shifts in investment from forelimbs to hindlimbs that were qualitatively similar to anatomical rearrangements observed in flightless birds. These findings suggest that island bird populations tend to evolve on a trajectory toward flightlessness, even if most remain volant. This pattern was consistent across nine families and four orders that vary in lifestyle, foraging behavior, flight style, and body size. These predictable shifts in avian morphology may reduce the physical capacity for escape via flight and diminish the potential for small-island taxa to diversify via dispersal.

  11. The Physics of Bird Flight: An Experiment

    Science.gov (United States)

    Mihail, Michael D.; George, Thomas F.; Feldman, Bernard J.

    2008-01-01

    This article describes an experiment that measures the forces acting on a flying bird during takeoff. The experiment uses a minimum of equipment and only an elementary knowledge of kinematics and Newton's second law. The experiment involves first digitally videotaping a bird during takeoff, analyzing the video to determine the bird's position as a…

  12. The North Sea Bird Club

    International Nuclear Information System (INIS)

    Doyle, P.A.T.; Gorman, M.L.; Patterson, I.J.; Howe, S.

    1991-01-01

    This paper reports that the creation of a club for the purpose of encouraging oil and gas workers to watch birds may not at first seem a viable proposition. To the layperson, birds offshore conjures up an image of hundreds of seagulls following fishing boats, and very little else. Also, the act of birdwatching is not seen as a typical offshore worker's activity. Anyone who has worked on an installation offshore and who has any interest in wildlife will be aware of the occasional presence of land-birds. Two decades ago, prompted by some keen offshore workers, a single oil company set up a monitoring program, which quickly became popular with a number of its employees. Birds seem offshore were recorded on data forms and collected together. At this stage the club was purely another recreation facility; however, when the data were collated it was soon realized that installations offshore were being used as staging posts by birds on migration, and that the information being collected would be of great interest in the study of bird movements. All over Britain, at strategic points on the coastline, there are bird observatories which record the arrival and departure of migrating birds. The presence of several hundred solid structures up and down the North Sea, which are used by birds en route, represents a huge, unique bird observatory, capable of uncovering facts about bird migration which have long eluded land-based scientists. Eleven years ago, the North Sea Bird Club began, composed of eight member companies, a recorder from Aberdeen University and a representative from the Nature Conservancy Council. The club received data from 41 installations, and the recorder collated these on Aberdeen University's computer and produced an annual report of sightings

  13. Role of wild birds as carriers of multi-drug resistant Escherichia coli and Escherichia vulneris

    Directory of Open Access Journals (Sweden)

    Mohammed Y. Shobrak

    2014-12-01

    Full Text Available Emergence and distribution of multi-drug resistant (MDR bacteria in environments pose a risk to human and animal health. A total of 82 isolates of Escherichia spp. were recovered from cloacal swabs of migrating and non-migrating wild birds. All bacterial isolates were identified and characterized morphologically and biochemically. 72% and 50% of isolates recovered from non-migrating and migrating birds, respectively, showed positive congo red dye binding (a virulence factor. Also, hemolysin production (a virulence factor was showed in 8% of isolates recovered from non-migrating birds and 75% of isolates recovered from migrating birds. All isolates recovered from non-migrating birds were found resistant to Oxacillin while all isolates recovered from migrating birds demonstrated resistance to Oxacillin, Chloramphenicol, Oxytetracycline and Lincomycin. Some bacterial isolates recovered from non-migrating birds and migrating birds exhibited MDR phenotype. The MDR isolates were further characterized by API 20E and 16S rRNA as E. coli and E. vulneris. MDR Escherichia isolates contain ~1-5 plasmids of high-molecular weights. Accordingly, wild birds could create a potential threat to human and animal health by transmitting MDR bacteria to water streams and other environmental sources through their faecal residues, and to remote regions by migration.

  14. Role of wild birds as carriers of multi-drug resistant Escherichia coli and Escherichia vulneris

    Science.gov (United States)

    Shobrak, Mohammed Y.; Abo-Amer, Aly E.

    2014-01-01

    Emergence and distribution of multi-drug resistant (MDR) bacteria in environments pose a risk to human and animal health. A total of 82 isolates of Escherichia spp. were recovered from cloacal swabs of migrating and non-migrating wild birds. All bacterial isolates were identified and characterized morphologically and biochemically. 72% and 50% of isolates recovered from non-migrating and migrating birds, respectively, showed positive congo red dye binding (a virulence factor). Also, hemolysin production (a virulence factor) was showed in 8% of isolates recovered from non-migrating birds and 75% of isolates recovered from migrating birds. All isolates recovered from non-migrating birds were found resistant to Oxacillin while all isolates recovered from migrating birds demonstrated resistance to Oxacillin, Chloramphenicol, Oxytetracycline and Lincomycin. Some bacterial isolates recovered from non-migrating birds and migrating birds exhibited MDR phenotype. The MDR isolates were further characterized by API 20E and 16S rRNA as E. coli and E. vulneris. MDR Escherichia isolates contain ~1–5 plasmids of high-molecular weights. Accordingly, wild birds could create a potential threat to human and animal health by transmitting MDR bacteria to water streams and other environmental sources through their faecal residues, and to remote regions by migration. PMID:25763023

  15. The effect of the Sep wind park near Oosterbierum, Friesland, The Netherlands, on birds

    International Nuclear Information System (INIS)

    Winkelman, J.E.

    1992-01-01

    The title study concerns the period 1984-1991. The wind park consists of 18 three-bladed 300 kW horizontal axis wind turbines of 35 meters height, and a rotor diameter of 30 meters, seven meteorological towers, and three cluster and control buildings. Aspects studied included disturbance of breeding, resting or feeding, and migrating birds, behavior of birds approaching the wind turbines during the day and night, and bird victims due to collision with the wind turbines and the meteorological towers. In this report data on the number of birds passing the wind park at night and the flight behavior of these birds during their passage are presented and discussed. The numbers were determined in the period 1985-1988 by using a search approach radar, two passive image intensifiers in combination with infrared spot lights, and a thermal image intensifier. Illumination of the wind turbines to avoid collisions is not believed to be necessary, because birds seem to be quite good at spotting the wind turbines, even during conditions of moderate visibility at night. 30 figs., 23 tabs., 18 app., 109 refs

  16. Prevalence of Campylobacter jejuni, C.lari and C.coli in different ecological guilds and taxa of migrating birds

    NARCIS (Netherlands)

    Waldenstrom, J.; Broman, T.; Carlsson, I.; Hasselquist, D.; Achterberg, R.P.; Wagenaar, J.A.; Olsen, B.

    2002-01-01

    A total of 1,794 migrating birds trapped at a coastal site in southern Sweden were sampled for detection of Campylobacter spp. All isolates phenotypically identified as Campylobacter jejuni and a subset of those identified as non-C. jejuni were identified to the species level by PCR-based

  17. New software methods in radar ornithology using WSR-88D weather data and potential application to monitoring effects of climate change on bird migration

    Science.gov (United States)

    Mead, Reginald; Paxton, John; Sojda, Richard S.; Swayne, David A.; Yang, Wanhong; Voinov, A.A.; Rizzoli, A.; Filatova, T.

    2010-01-01

    Radar ornithology has provided tools for studying the movement of birds, especially related to migration. Researchers have presented qualitative evidence suggesting that birds, or at least migration events, can be identified using large broad scale radars such as the WSR-88D used in the NEXRAD weather surveillance system. This is potentially a boon for ornithologists because such data cover a large portion of the United States, are constantly being produced, are freely available, and have been archived since the early 1990s. A major obstacle to this research, however, has been that identifying birds in NEXRAD data has required a trained technician to manually inspect a graphically rendered radar sweep. A single site completes one volume scan every five to ten minutes, producing over 52,000 volume scans in one year. This is an immense amount of data, and manual classification is infeasible. We have developed a system that identifies biological echoes using machine learning techniques. This approach begins with training data using scans that have been classified by experts, or uses bird data collected in the field. The data are preprocessed to ensure quality and to emphasize relevant features. A classifier is then trained using this data and cross validation is used to measure performance. We compared neural networks, naive Bayes, and k-nearest neighbor classifiers. Empirical evidence is provided showing that this system can achieve classification accuracies in the 80th to 90th percentile. We propose to apply these methods to studying bird migration phenology and how it is affected by climate variability and change over multiple temporal scales.

  18. A Phororhacoid bird from the Eocene of Africa

    Science.gov (United States)

    Mourer-Chauviré, Cécile; Tabuce, Rodolphe; Mahboubi, M'hammed; Adaci, Mohammed; Bensalah, Mustapha

    2011-10-01

    The bird fossil record is globally scarce in Africa. The early Tertiary evolution of terrestrial birds is virtually unknown in that continent. Here, we report on a femur of a large terrestrial new genus discovered from the early or early middle Eocene (between ˜52 and 46 Ma) of south-western Algeria. This femur shows all the morphological features of the Phororhacoidea, the so-called Terror Birds. Most of the phororhacoids were indeed large, or even gigantic, flightless predators or scavengers with no close modern analogs. It is likely that this extinct group originated in South America, where they are known from the late Paleocene to the late Pleistocene (˜59 to 0.01 Ma). The presence of a phororhacoid bird in Africa cannot be explained by a vicariant mechanism because these birds first appeared in South America well after the onset of the mid-Cretaceous Gondwana break up (˜100 million years old). Here, we propose two hypotheses to account for this occurrence, either an early dispersal of small members of this group, which were still able of a limited flight, or a transoceanic migration of flightless birds from South America to Africa during the Paleocene or earliest Eocene. Paleogeographic reconstructions of the South Atlantic Ocean suggest the existence of several islands of considerable size between South America and Africa during the early Tertiary, which could have helped a transatlantic dispersal of phororhacoids.

  19. Automatic identification of bird targets with radar via patterns produced by wing flapping

    NARCIS (Netherlands)

    Zaugg, S.; Saporta, G.; van Loon, E.; Schmaljohann, H.; Liechti, F.

    2008-01-01

    Bird identification with radar is important for bird migration research, environmental impact assessments (e.g. wind farms), aircraft security and radar meteorology. In a study on bird migration, radar signals from birds, insects and ground clutter were recorded. Signals from birds show a typical

  20. The trans-Himalayan flights of bar-headed geese (Anser indicus)

    Science.gov (United States)

    Hawkes, L.A.; Balachandran, S.; Batbayar, N.; Butler, P.J.; Frappell, P.B.; Milsom, W.K.; Tseveenmyadag, N.; Newman, S.H.; Scott, G.R.; Sathiyaselvam, P.; Takekawa, John Y.; Wikelski, M.; Bishop, C.M.

    2011-01-01

    Birds that fly over mountain barriers must be capable of meeting the increased energetic cost of climbing in low-density air, even though less oxygen may be available to support their metabolism. This challenge is magnified by the reduction in maximum sustained climbing rates in large birds. Bar-headed geese (Anser indicus) make one of the highest and most iconic transmountain migrations in the world. We show that those populations of geese that winter at sea level in India are capable of passing over the Himalayas in 1 d, typically climbing between 4,000 and 6,000min 7-8 h. Surprisingly, these birds do not rely on the assistance of upslope tailwinds that usually occur during the day and can support minimum climb rates of 0.8-2.2 km??h-1, even in the relative stillness of the night. They appear to strategically avoid higher speed winds during the afternoon, thus maximizing safety and control during flight. It would seem, therefore, that bar-headed geese are capable of sustained climbing flight over the passes of the Himalaya under their own aerobic power.

  1. Intake rates, stochasticity, or onset of spring – what aspects of food availability affect spring migration patterns in Pink-footed Geese Anser brachyrhynchus?

    NARCIS (Netherlands)

    Bauer, S.; Madsen, J.; Klaassen, M.R.J.

    2006-01-01

    Long-distance bird migration consists of several flight episodes interrupted by a series of resting and refuelling periods on stopover sites. We assessed the role of food availability as the determinant of staging decisions focusing on the following three aspects of food availability: intake rates,

  2. The bat-bird-bug battle: daily flight activity of insects and their predators over a rice field revealed by high-resolution Scheimpflug Lidar

    Science.gov (United States)

    Malmqvist, Elin; Jansson, Samuel; Zhu, Shiming; Li, Wansha; Svanberg, Katarina; Svanberg, Sune; Rydell, Jens; Song, Ziwei; Bood, Joakim; Brydegaard, Mikkel; Åkesson, Susanne

    2018-04-01

    We present the results of, to our knowledge, the first Lidar study applied to continuous and simultaneous monitoring of aerial insects, bats and birds. It illustrates how common patterns of flight activity, e.g. insect swarming around twilight, depend on predation risk and other constraints acting on the faunal components. Flight activity was monitored over a rice field in China during one week in July 2016, using a high-resolution Scheimpflug Lidar system. The monitored Lidar transect was about 520 m long and covered approximately 2.5 m3. The observed biomass spectrum was bimodal, and targets were separated into insects and vertebrates in a categorization supported by visual observations. Peak flight activity occurred at dusk and dawn, with a 37 min time difference between the bat and insect peaks. Hence, bats started to feed in declining insect activity after dusk and stopped before the rise in activity before dawn. A similar time difference between insects and birds may have occurred, but it was not obvious, perhaps because birds were relatively scarce. Our observations are consistent with the hypothesis that flight activity of bats is constrained by predation in bright light, and that crepuscular insects exploit this constraint by swarming near to sunset/sunrise to minimize predation from bats.

  3. Role of wing color and seasonal changes in ambient temperature and solar irradiation on predicted flight efficiency of the Albatross.

    Science.gov (United States)

    Hassanalian, M; Throneberry, G; Ali, M; Ben Ayed, S; Abdelkefi, A

    2018-01-01

    Drag reduction of the wings of migrating birds is crucial to their flight efficiency. Wing color impacts absorption of solar irradiation which may affect drag but there is little known in this area. To this end, the drag reduction induced by the thermal effect of the wing color of migrating birds with unpowered flight modes is presented in this study. Considering this natural phenomenon in the albatross as an example of migrating birds, and applying an energy balance for this biological system, a thermal analysis is performed on the wings during the summer and winter to obtain different ranges of air density, viscosity, and wing surface temperature brought about from a range of ambient temperatures and climatic conditions seen in different seasons and to study their effects. The exact shape of the albatross wing is used and nine different wing colors are considered in order to gain a better understanding of the effect different colors' absorptivities make on the change in aerodynamic performances. The thermal effect is found to be more important during the summer than during the winter due to the higher values of solar irradiation and a maximum drag reduction of 7.8% is found in summer changing the wing color from light white to dark black. The obtained results show that albatrosses with darker colored wings are more efficient (constant lift to drag ratio and drag reduction) and have better endurance due to this drag reduction. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Detecting mismatches of bird migration stopover and tree phenology in response to changing climate

    Science.gov (United States)

    Kellermann, Jherime L.; van Riper, Charles

    2015-01-01

    Migratory birds exploit seasonal variation in resources across latitudes, timing migration to coincide with the phenology of food at stopover sites. Differential responses to climate in phenology across trophic levels can result in phenological mismatch; however, detecting mismatch is sensitive to methodology. We examined patterns of migrant abundance and tree flowering, phenological mismatch, and the influence of climate during spring migration from 2009 to 2011 across five habitat types of the Madrean Sky Islands in southeastern Arizona, USA. We used two metrics to assess phenological mismatch: synchrony and overlap. We also examined whether phenological overlap declined with increasing difference in mean event date of phenophases. Migrant abundance and tree flowering generally increased with minimum spring temperature but depended on annual climate by habitat interactions. Migrant abundance was lowest and flowering was highest under cold, snowy conditions in high elevation montane conifer habitat while bird abundance was greatest and flowering was lowest in low elevation riparian habitat under the driest conditions. Phenological synchrony and overlap were unique and complementary metrics and should both be used when assessing mismatch. Overlap declined due to asynchronous phenologies but also due to reduced migrant abundance or flowering when synchrony was actually maintained. Overlap declined with increasing difference in event date and this trend was strongest in riparian areas. Montane habitat specialists may be at greatest risk of mismatch while riparian habitat could provide refugia during dry years for phenotypically plastic species. Interannual climate patterns that we observed match climate change projections for the arid southwest, altering stopover habitat condition.

  5. Emerging practices of wind farm planning in a dense bird migration area

    DEFF Research Database (Denmark)

    Clausen, Niels-Erik; Mortensen, N.G.; Hansen, J.C.

    2003-01-01

    The objective of this paper is to present part of The Wind Atlas for Egypt project aiming at developing a firm basis for planning and utilization of the vast wind energy resources available in Egypt. The project should recommend a common planning framework for wind farm development in Egypt...... is briefly introduced. As a case study to illustrate the planning process a 60 MW wind farm located at the Gulf of El-Zayt at the Gulf of Suez in Egypt will be analysed. This area is chosen for its very high wind energy potential and the high concentration of migrating birds during spring and autumn. During...... the site selection and layout of a wind farm the balancing of interests and land use will be described....

  6. Flights of fear: a mechanical wing whistle sounds the alarm in a flocking bird.

    Science.gov (United States)

    Hingee, Mae; Magrath, Robert D

    2009-12-07

    Animals often form groups to increase collective vigilance and allow early detection of predators, but this benefit of sociality relies on rapid transfer of information. Among birds, alarm calls are not present in all species, while other proposed mechanisms of information transfer are inefficient. We tested whether wing sounds can encode reliable information on danger. Individuals taking off in alarm fly more quickly or ascend more steeply, so may produce different sounds in alarmed than in routine flight, which then act as reliable cues of alarm, or honest 'index' signals in which a signal's meaning is associated with its method of production. We show that crested pigeons, Ocyphaps lophotes, which have modified flight feathers, produce distinct wing 'whistles' in alarmed flight, and that individuals take off in alarm only after playback of alarmed whistles. Furthermore, amplitude-manipulated playbacks showed that response depends on whistle structure, such as tempo, not simply amplitude. We believe this is the first demonstration that flight noise can send information about alarm, and suggest that take-off noise could provide a cue of alarm in many flocking species, with feather modification evolving specifically to signal alarm in some. Similar reliable cues or index signals could occur in other animals.

  7. Bird Flight and Satish Dhawan

    Indian Academy of Sciences (India)

    and birds has inspired poetry, art, l~terature, science and tech- nology. In Monsoon, Wilbur ... Henk Tennekes, an aerospace engineering professor at Pennsyl- vania State University, USA, has a different story to tell in his popular book The ...

  8. Assessing collision risk for birds and bats : radar survey

    Energy Technology Data Exchange (ETDEWEB)

    Brunet, R. [Genivar SEC, Sherbrooke, PQ (Canada)

    2010-07-01

    This PowerPoint presentation described some of the inventories and instrumentation available for monitoring winged fauna in and around wind farms. In addition to visual observations, bird calls and songs can be recorded to determine the amount and different types of birds located at wind farm sites. Radio-telemetry devices are also used to evaluate bird activities, and nest searches are conducted to determine the amount of eggs or young birds that will soon add to the bird population. Between 90 and 100 percent of birds and bats migrate at night. Acoustic radar, Doppler radar, and maritime surveillance radar instruments are used to monitor night-time activities in wind farm locations. Doppler radar is also used to detect bird and bat migration corridors. Screen-shots of various radar interfaces were presented. tabs., figs.

  9. The paradox of extreme high-altitude migration in bar-headed geese Anser indicus

    Science.gov (United States)

    Hawkes, L. A.; Balachandran, S.; Batbayar, N.; Butler, P. J.; Chua, B.; Douglas, D. C.; Frappell, P. B.; Hou, Y.; Milsom, W. K.; Newman, S. H.; Prosser, D. J.; Sathiyaselvam, P.; Scott, G. R.; Takekawa, J. Y.; Natsagdorj, T.; Wikelski, M.; Witt, M. J.; Yan, B.; Bishop, C. M.

    2013-01-01

    Bar-headed geese are renowned for migratory flights at extremely high altitudes over the world's tallest mountains, the Himalayas, where partial pressure of oxygen is dramatically reduced while flight costs, in terms of rate of oxygen consumption, are greatly increased. Such a mismatch is paradoxical, and it is not clear why geese might fly higher than is absolutely necessary. In addition, direct empirical measurements of high-altitude flight are lacking. We test whether migrating bar-headed geese actually minimize flight altitude and make use of favourable winds to reduce flight costs. By tracking 91 geese, we show that these birds typically travel through the valleys of the Himalayas and not over the summits. We report maximum flight altitudes of 7290 m and 6540 m for southbound and northbound geese, respectively, but with 95 per cent of locations received from less than 5489 m. Geese travelled along a route that was 112 km longer than the great circle (shortest distance) route, with transit ground speeds suggesting that they rarely profited from tailwinds. Bar-headed geese from these eastern populations generally travel only as high as the terrain beneath them dictates and rarely in profitable winds. Nevertheless, their migration represents an enormous challenge in conditions where humans and other mammals are only able to operate at levels well below their sea-level maxima. PMID:23118436

  10. Migration stopover ecology of western avian populations: A southwestern migration workshop

    Science.gov (United States)

    Skagen, Susan K.; Melcher, Cynthia P.; Hazelwood, Rob

    2004-01-01

    The importance of migration stopover sites in ensuring that migratory birds successfully accomplish their journeys between breeding and non-breeding ranges has come to the forefront of avian research. Migratory birds that breed in western United States (US) and Canada and overwinter primarily in western Mexico migrate across the arid region of northern Mexico and southwestern US. Many of these migrants use lowland riparian stopover habitats, which comprise less than 0.1% of the western U.S. landscape. These habitats represent a significant conservation priority.

  11. Converging migration routes of Eurasian hobbies Falco subbuteo crossing the African equatorial rain forest.

    Science.gov (United States)

    Strandberg, Roine; Klaassen, Raymond H G; Hake, Mikael; Olofsson, Patrik; Alerstam, Thomas

    2009-02-22

    Autumn migration of adult Eurasian hobbies Falco subbuteo from Europe to southern Africa was recorded by satellite telemetry and observed routes were compared with randomly simulated routes. Two non-random features of observed routes were revealed: (i) shifts to more westerly longitudes than straight paths to destinations and (ii) strong route convergence towards a restricted area close to the equator (1 degree S, 15 degrees E). The birds migrated south or southwest to approximately 10 degrees N, where they changed to south-easterly courses. The maximal spread between routes at 10 degrees N (2134 km) rapidly decreased to a minimum (67 km) close to the equator. We found a striking relationship between the route convergence and the distribution of continuous rainforest, suggesting that hobbies minimize flight distance across the forest, concentrating in a corridor where habitat may be more suitable for travelling and foraging. With rainforest forming a possible ecological barrier, many migrants may cross the equator either at 15 degrees E, similar to the hobbies, or at 30-40 degrees E, east of the rainforest where large-scale migration is well documented. Much remains to be understood about the role of the rainforest for the evolution and future of the trans-equatorial Palaearctic-African bird migration systems.

  12. Bird migration and avian influenza: a comparison of hydrogen stable isotopes and satellite tracking methods

    Science.gov (United States)

    Bridge, Eli S.; Kelly, Jeffrey F.; Xiao, Xiangming; Takekawa, John Y.; Hill, Nichola J.; Yamage, Mat; Haque, Enam Ul; Islam, Mohammad Anwarul; Mundkur, Taej; Yavuz, Kiraz Erciyas; Leader, Paul; Leung, Connie Y.H.; Smith, Bena; Spragens, Kyle A.; Vandegrift, Kurt J.; Hosseini, Parviez R.; Saif, Samia; Mohsanin, Samiul; Mikolon, Andrea; Islam, Ausrafal; George, Acty; Sivananinthaperumal, Balachandran; Daszak, Peter; Newman, Scott H.

    2014-01-01

    Satellite-based tracking of migratory waterfowl is an important tool for understanding the potential role of wild birds in the long-distance transmission of highly pathogenic avian influenza. However, employing this technique on a continental scale is prohibitively expensive. This study explores the utility of stable isotope ratios in feathers in examining both the distances traveled by migratory birds and variation in migration behavior. We compared the satellite-derived movement data of 22 ducks from 8 species captured at wintering areas in Bangladesh, Turkey, and Hong Kong with deuterium ratios (δD) in the feathers of these and other individuals captured at the same locations. We derived likely molting locations from the satellite tracking data and generated expected isotope ratios based on an interpolated map of δD in rainwater. Although δD was correlated with the distance between wintering and molting locations, surprisingly, measured δD values were not correlated with either expected values or latitudes of molting sites. However, population-level parameters derived from the satellite-tracking data, such as mean distance between wintering and molting locations and variation in migration distance, were reflected by means and variation of the stable isotope values. Our findings call into question the relevance of the rainfall isotope map for Asia for linking feather isotopes to molting locations, and underscore the need for extensive ground truthing in the form of feather-based isoscapes. Nevertheless, stable isotopes from feathers could inform disease models by characterizing the degree to which regional breeding populations interact at common wintering locations. Feather isotopes also could aid in surveying wintering locations to determine where high-resolution tracking techniques (e.g. satellite tracking) could most effectively be employed. Moreover, intrinsic markers such as stable isotopes offer the only means of inferring movement information from

  13. Detours in long-distance migration across the Qinghai-Tibetan Plateau: individual consistency and habitat associations.

    Science.gov (United States)

    Liu, Dongping; Zhang, Guogang; Jiang, Hongxing; Lu, Jun

    2018-01-01

    Migratory birds often follow detours when confronted with ecological barriers, and understanding the extent and the underlying drivers of such detours can provide important insights into the associated cost to the annual energy budget and the migration strategies. The Qinghai-Tibetan Plateau is the most daunting geographical barrier for migratory birds because the partial pressure of oxygen is dramatically reduced and flight costs greatly increase. We analyzed the repeated migration detours and habitat associations of four Pallas's Gulls Larus ichthyaetus across the Qinghai-Tibetan Plateau over 22 migration seasons. Gulls exhibited notable detours, with the maximum distance being more than double that of the expected shortest route, that extended rather than reduced the passage across the plateau. The extent of longitudinal detours significantly increased with latitude, and detours were longer in autumn than in spring. Compared with the expected shortest routes, proximity to water bodies increased along autumn migration routes, but detour-habitat associations were weak along spring migration routes. Thus, habitat availability was likely one, but not the only, factor shaping the extent of detours, and migration routes were determined by different mechanisms between seasons. Significant between-individual variation but high individual consistency in migration timing and routes were revealed in both seasons, indicating a stronger influence of endogenous schedules than local environmental conditions. Gulls may benefit from repeated use of familiar routes and stopover sites, which may be particularly significant in the challenging environment of the Qinghai-Tibetan Plateau.

  14. Climate change leads to decreasing bird migration distances

    NARCIS (Netherlands)

    Visser, M.E.; Perdeck, A.C.; van Balen, J.H.; Both, C.

    2009-01-01

    Global climate change has led to warmer winters in NW Europe, shortening the distance between suitable overwintering areas and the breeding areas of many bird species. Here we show that winter recovery distances have decreased over the past seven decades, for birds ringed during the breeding season

  15. Climate change leads to decreasing bird migration distances

    NARCIS (Netherlands)

    Visser, Marcel E.; Perdeck, Albert C.; van Balen, Johan H.; Both, Christiaan

    Global climate change has led to warmer winters in NW Europe, shortening the distance between suitable overwintering areas and the breeding areas of many bird species. Here we show that winter recovery distances have decreased over the past seven decades, for birds ringed during the breeding season

  16. Landscape movements of migratory birds and bats reveal an expanded scale of stopover.

    Directory of Open Access Journals (Sweden)

    Philip D Taylor

    Full Text Available Many species of birds and bats undertake seasonal migrations between breeding and over-wintering sites. En-route, migrants alternate periods of flight with time spent at stopover--the time and space where individuals rest and refuel for subsequent flights. We assessed the spatial scale of movements made by migrants during stopover by using an array of automated telemetry receivers with multiple antennae to track the daily location of individuals over a geographic area ~20 × 40 km. We tracked the movements of 322 individuals of seven migratory vertebrate species (5 passerines, 1 owl and 1 bat during spring and fall migratory stopover on and adjacent to a large lake peninsula. Our results show that many individuals leaving their capture site relocate within the same landscape at some point during stopover, moving as much as 30 km distant from their site of initial capture. We show that many apparent nocturnal departures from stopover sites are not a resumption of migration in the strictest sense, but are instead relocations that represent continued stopover at a broader spatial scale.

  17. Candidate genes have sex-specific effects on timing of spring migration and moult speed in a long-distance migratory bird.

    Science.gov (United States)

    Bazzi, Gaia; Podofillini, Stefano; Gatti, Emanuele; Gianfranceschi, Luca; Cecere, Jacopo G; Spina, Fernando; Saino, Nicola; Rubolini, Diego

    2017-10-01

    The timing of major life-history events, such as migration and moult, is set by endogenous circadian and circannual clocks, that have been well characterized at the molecular level. Conversely, the genetic sources of variation in phenology and in other behavioral traits have been sparsely addressed. It has been proposed that inter-individual variability in the timing of seasonal events may arise from allelic polymorphism at phenological candidate genes involved in the signaling cascade of the endogenous clocks. In this study of a long-distance migratory passerine bird, the willow warbler Phylloscopus trochilus , we investigated whether allelic variation at 5 polymorphic loci of 4 candidate genes ( Adcyap1 , Clock , Creb1 , and Npas2 ), predicted 2 major components of the annual schedule, namely timing of spring migration across the central Mediterranean sea and moult speed, the latter gauged from ptilochronological analyses of tail feathers moulted in the African winter quarters. We identified a novel Clock gene locus ( Clock region 3) showing polyQ polymorphism, which was however not significantly associated with any phenotypic trait. Npas2 allele size predicted male (but not female) spring migration date, with males bearing longer alleles migrating significantly earlier than those bearing shorter alleles. Creb1 allele size significantly predicted male (but not female) moult speed, longer alleles being associated with faster moult. All other genotype-phenotype associations were statistically non-significant. These findings provide new evidence for a role of candidate genes in modulating the phenology of different circannual activities in long-distance migratory birds, and for the occurrence of sex-specific candidate gene effects.

  18. Motorized Migrations: the Future or Mere Fantasy?

    Science.gov (United States)

    Ellis, D.H.; Sladen, William J. L.; Lishman, W.A.; Clegg, K.R.; Duff, J.W.; Gee, G.F.; Lewis, J.C.

    2003-01-01

    In 15 experiments from 1993-2002, we led cranes, geese, or swans on their first southward migration with either ultralight aircraft or vehicles on the ground. These experiments reveal that large birds can be readily trained to follow and most will return north (and south) in subsequent migrations unassisted. These techniques can now be used to teach birds new (or forgotten) migration paths. Although we are constantly improving our training techniques, we now have an operational program that can be broadly applied to those species where juveniles learn migration routes from their parents.

  19. Basal metabolic rate and risk-taking behaviour in birds.

    Science.gov (United States)

    Møller, A P

    2009-12-01

    Basal metabolic rate (BMR) constitutes the minimal metabolic rate in the zone of thermo-neutrality, where heat production is not elevated for temperature regulation. BMR thus constitutes the minimum metabolic rate that is required for maintenance. Interspecific variation in BMR in birds is correlated with food habits, climate, habitat, flight activity, torpor, altitude, and migration, although the selective forces involved in the evolution of these presumed adaptations are not always obvious. I suggest that BMR constitutes the minimum level required for maintenance, and that variation in this minimum level reflects the fitness costs and benefits in terms of ability to respond to selective agents like predators, implying that an elevated level of BMR is a cost of wariness towards predators. This hypothesis predicts a positive relationship between BMR and measures of risk taking such as flight initiation distance (FID) of individuals approached by a potential predator. Consistent with this suggestion, I show in a comparative analysis of 76 bird species that species with higher BMR for their body mass have longer FID when approached by a potential predator. This effect was independent of potentially confounding variables and similarity among species due to common phylogenetic descent. These results imply that BMR is positively related to risk-taking behaviour, and that predation constitutes a neglected factor in the evolution of BMR.

  20. Five years of monitoring bird strike potential at a mountain-top wind turbine, Yukon Territory

    Energy Technology Data Exchange (ETDEWEB)

    Mossop, D.H. [Yukon College, Whitehorse, YT (Canada)

    1997-12-31

    A five-year study was conducted to determine if birds were at risk of collision with an experimental wind turbine on a 1,500 metre mountain near the major Shakwak migration corridor used by many thousands of birds. More than 100 ground searches at the turbine site and about 80 hours of migration watch were conducted. In five years, six birds hit the control tower, none hit the turbine tower. All strikes were in winter and none of the birds killed were in migration. Waterfowl were found to navigate in the valley centre about 1,000 feet below the turbine. Small birds were rarely found at the altitude where the turbine was located. Raptors were the most common birds found near the site, but they were able to avoid the tower. It was concluded that birds using the migration corridor near Whitehorse were not at great risk of collision with towers above 1,200 metre altitude. 7 refs., 3 tabs., 6 figs.

  1. Meteorological and environmental variables affect flight behaviour and decision-making of an obligate soaring bird, the California Condor Gymnogyps californianus

    Science.gov (United States)

    Poessel, Sharon; Brandt, Joseph; Miller, Tricia A.; Katzner, Todd

    2018-01-01

    The movements of animals are limited by evolutionary constraints and ecological processes and are strongly influenced by the medium through which they travel. For flying animals, variation in atmospheric conditions is critically influential in movement. Obligate soaring birds depend on external sources of updraft more than do other flying species, as without that updraft they are unable to sustain flight for extended periods. These species are therefore good models for understanding how the environment can influence decisions about movement. We used meteorological and topographic variables to understand the environmental influences on the decision to engage in flight by obligate soaring and critically endangered California Condors Gymnogyps californianus. Condors were more likely to fly, soared at higher altitudes and flew over smoother terrain when weather conditions promoted either thermal or orographic updrafts, for example when turbulence and solar radiation were higher and when winds from the east and north were stronger. However, increased atmospheric stability, which is inconsistent with thermal development but may be associated with orographic updrafts, was correlated with a somewhat higher probability of being in flight at lower altitudes and over rougher terrain. The close and previously undescribed linkages between Condor flight and conditions that support development of thermal and orographic updrafts provide important insight into the behaviour of obligate soaring birds and into the environmental parameters that may define the currently expanding distribution of Condors within and outside the state of California.

  2. Anatomy and histochemistry of spread-wing posture in birds. 3. Immunohistochemistry of flight muscles and the "shoulder lock" in albatrosses.

    Science.gov (United States)

    Meyers, Ron A; Stakebake, Eric F

    2005-01-01

    As a postural behavior, gliding and soaring flight in birds requires less energy than flapping flight. Slow tonic and slow twitch muscle fibers are specialized for sustained contraction with high fatigue resistance and are typically found in muscles associated with posture. Albatrosses are the elite of avian gliders; as such, we wanted to learn how their musculoskeletal system enables them to maintain spread-wing posture for prolonged gliding bouts. We used dissection and immunohistochemistry to evaluate muscle function for gliding flight in Laysan and Black-footed albatrosses. Albatrosses possess a locking mechanism at the shoulder composed of a tendinous sheet that extends from origin to insertion throughout the length of the deep layer of the pectoralis muscle. This fascial "strut" passively maintains horizontal wing orientation during gliding and soaring flight. A number of muscles, which likely facilitate gliding posture, are composed exclusively of slow fibers. These include Mm. coracobrachialis cranialis, extensor metacarpi radialis dorsalis, and deep pectoralis. In addition, a number of other muscles, including triceps scapularis, triceps humeralis, supracoracoideus, and extensor metacarpi radialis ventralis, were found to have populations of slow fibers. We believe that this extensive suite of uniformly slow muscles is associated with sustained gliding and is unique to birds that glide and soar for extended periods. These findings suggest that albatrosses utilize a combination of slow muscle fibers and a rigid limiting tendon for maintaining a prolonged, gliding posture.

  3. Ocean-wide Drivers of Migration Strategies and Their Influence on Population Breeding Performance in a Declining Seabird.

    Science.gov (United States)

    Fayet, Annette L; Freeman, Robin; Anker-Nilssen, Tycho; Diamond, Antony; Erikstad, Kjell E; Fifield, Dave; Fitzsimmons, Michelle G; Hansen, Erpur S; Harris, Mike P; Jessopp, Mark; Kouwenberg, Amy-Lee; Kress, Steve; Mowat, Stephen; Perrins, Chris M; Petersen, Aevar; Petersen, Ib K; Reiertsen, Tone K; Robertson, Gregory J; Shannon, Paula; Sigurðsson, Ingvar A; Shoji, Akiko; Wanless, Sarah; Guilford, Tim

    2017-12-18

    Which factors shape animals' migration movements across large geographical scales, how different migratory strategies emerge between populations, and how these may affect population dynamics are central questions in the field of animal migration [1] that only large-scale studies of migration patterns across a species' range can answer [2]. To address these questions, we track the migration of 270 Atlantic puffins Fratercula arctica, a red-listed, declining seabird, across their entire breeding range. We investigate the role of demographic, geographical, and environmental variables in driving spatial and behavioral differences on an ocean-basin scale by measuring puffins' among-colony differences in migratory routes and day-to-day behavior (estimated with individual daily activity budgets and energy expenditure). We show that competition and local winter resource availability are important drivers of migratory movements, with birds from larger colonies or with poorer local winter conditions migrating further and visiting less-productive waters; this in turn led to differences in flight activity and energy expenditure. Other behavioral differences emerge with latitude, with foraging effort and energy expenditure increasing when birds winter further north in colder waters. Importantly, these ocean-wide migration patterns can ultimately be linked with breeding performance: colony productivity is negatively associated with wintering latitude, population size, and migration distance, which demonstrates the cost of competition and migration on future breeding and the link between non-breeding and breeding periods. Our results help us to understand the drivers of animal migration and have important implications for population dynamics and the conservation of migratory species. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Conserving migratory land birds in the new world: do we know enough?

    Science.gov (United States)

    Faaborg, John; Holmes, Richard T; Anders, Angela D; Bildstein, Keith L; Dugger, Katie M; Gauthreaux, Sidney A; Heglund, Patricia; Hobson, Keith A; Jahn, Alex E; Johnson, Douglas H; Latta, Steven C; Levey, Douglas J; Marra, Peter P; Merkord, Christopher L; Nol, Erica; Rothstein, Stephen I; Sherry, Thomas W; Sillett, T Scott; Thompson, Frank R; Warnock, Nils

    2010-03-01

    Migratory bird needs must be met during four phases of the year: breeding season, fall migration, wintering, and spring migration; thus, management may be needed during all four phases. The bulk of research and management has focused on the breeding season, although several issues remain unsettled, including the spatial extent of habitat influences on fitness and the importance of habitat on the breeding grounds used after breeding. Although detailed investigations have shed light on the ecology and population dynamics of a few avian species, knowledge is sketchy for most species. Replication of comprehensive studies is needed for multiple species across a range of areas, Information deficiencies are even greater during the wintering season, when birds require sites that provide security and food resources needed for survival and developing nutrient reserves for spring migration and, possibly, reproduction. Research is needed on many species simply to identify geographic distributions, wintering sites, habitat use, and basic ecology. Studies are complicated, however, by the mobility of birds and by sexual segregation during winter. Stable-isotope methodology has offered an opportunity to identify linkages between breeding and wintering sites, which facilitates understanding the complete annual cycle of birds. The twice-annual migrations are the poorest-understood events in a bird's life. Migration has always been a risky undertaking, with such anthropogenic features as tall buildings, towers, and wind generators adding to the risk. Species such as woodland specialists migrating through eastern North America have numerous options for pausing during migration to replenish nutrients, but some species depend on limited stopover locations. Research needs for migration include identifying pathways and timetables of migration, quality and distribution of habitats, threats posed by towers and other tall structures, and any bottlenecks for migration. Issues such as human

  5. Plumage quality mediates a life-history trade-off in a migratory bird.

    Science.gov (United States)

    Podlaszczuk, Patrycja; Kamiński, Maciej; Włodarczyk, Radosław; Kaczmarek, Krzysztof; Janiszewski, Tomasz; Minias, Piotr

    2016-01-01

    Moult is one of the most costly activities in the annual cycle of birds and most avian species separate moult from other energy-demanding activities, such as migration. To this end, young birds tend to undergo the first post-juvenile moult before the onset of migration, but in some species the time window for the pre-migratory feather replacement is too narrow. We hypothesized that in such species an increased investment in the structural quality of juvenile feathers may allow to retain juvenile plumage throughout the entire migratory period and delay moult until arriving at wintering grounds, thus avoiding a moult-migration overlap. The effect of juvenile plumage quality on the occurrence of moult-migration overlap was studied in a migratory shorebird, the common snipe Gallinago gallinago . Ca. 400 of first-year common snipe were captured during their final stage of autumn migration through Central Europe. The quality of juvenile feathers was assessed as the mass-length residuals of retained juvenile rectrices. Condition of migrating birds was assessed with the mass of accumulated fat reserves and whole-blood hemoglobin concentration. Path analysis was used to disentangle complex interrelationships between plumage quality, moult and body condition. Snipe which grew higher-quality feathers in the pre-fledging period were less likely to initiate moult during migration. Individuals moulting during migration had lower fat loads and hemoglobin concentrations compared to non-moulting birds, suggesting a trade-off in resource allocation, where energetic costs of moult reduced both energy reserves available for migration and resources available for maintenance of high oxygen capacity of blood. The results of this study indicate that a major life-history trade-off in a migratory bird may be mediated by the quality of juvenile plumage. This is consistent with a silver spoon effect, where early-life investment in feather quality affects future performance of birds during

  6. Light-Activated Magnetic Compass in Birds

    DEFF Research Database (Denmark)

    Solov'yov, Ilia; Greiner, Walter

    2013-01-01

    Migrating birds fly thousand miles without having a map, or a GPS unit. But they may carry their own sensitive navigational tool, which allows them "see" the Earth’s magnetic field. Here we review the important physical and chemical constraints on a possible compass sensor and discuss the suggest......Migrating birds fly thousand miles without having a map, or a GPS unit. But they may carry their own sensitive navigational tool, which allows them "see" the Earth’s magnetic field. Here we review the important physical and chemical constraints on a possible compass sensor and discuss...... the suggestion that radical pairs in a photoreceptor cryptochrome might provide a biological realization for a magnetic compass. Finally, we review the current evidence supporting a role for radical pair reactions in the magnetic compass of birds....

  7. Limitations and mechanisms influencing the migratory performance of soaring birds

    Science.gov (United States)

    Tricia A. Miller; Brooks Robert P.; Michael J. Lanzone; David Brandes; Jeff Cooper; Junior A. Tremblay; Jay Wilhelm; Adam Duerr; Todd E. Katzner

    2016-01-01

    Migration is costly in terms of time, energy and safety. Optimal migration theory suggests that individual migratory birds will choose between these three costs depending on their motivation and available resources. To test hypotheses about use of migratory strategies by large soaring birds, we used GPS telemetry to track 18 adult, 13 sub-adult and 15 juvenile Golden...

  8. Exploring bird aerodynamics using radio-controlled models

    International Nuclear Information System (INIS)

    Hoey, Robert G

    2010-01-01

    A series of radio-controlled glider models was constructed by duplicating the aerodynamic shape of soaring birds (raven, turkey vulture, seagull and pelican). Controlled tests were conducted to determine the level of longitudinal and lateral-directional static stability, and to identify the characteristics that allowed flight without a vertical tail. The use of tail-tilt for controlling small bank-angle changes, as observed in soaring birds, was verified. Subsequent tests, using wing-tip ailerons, inferred that birds use a three-dimensional flow pattern around the wing tip (wing tip vortices) to control adverse yaw and to create a small amount of forward thrust in gliding flight.

  9. Bird on a (live) wire

    Energy Technology Data Exchange (ETDEWEB)

    Farr, M.

    2003-09-30

    Bird mortality as a result of contact with power lines is discussed. U. S. statistics are cited, according to which 174 million birds annually die as a result of contact with power lines, specifically when birds touch two phases of current at the same time. Raptors are particularly vulnerable to power-line electrocution due to their habit of perching on the highest vantage point available as they survey the ground for prey. Hydro lines located in agricultural areas, with bodies of water on one side and fields on the other, also obstruct flight of waterfowl as dusk and dawn when visibility is low. Various solutions designed to minimize the danger to birds are discussed. Among these are: changing the configuration of wires and cross arms to make them more visible to birds in flight and less tempting as perches, and adding simple wire markers such as flags, balloons, and coloured luminescent clips that flap and twirl in the wind. There is no evidence of any coordinated effort to deal with this problem in Ontario. However, a report is being prepared for submission to Environment Canada outlining risks to birds associated with the growing number of wind turbine power generators (negligible compared with power lines and communications towers), and offering suggestions on remedial measures. The Fatal Light Awareness Program (FLAP) also plans to lobby the Canadian Wildlife Service to discuss the possibility of coordinating efforts to monitor, educate about and ultimately reduce this form of bird mortality.

  10. Probabilistic divergence time estimation without branch lengths: dating the origins of dinosaurs, avian flight and crown birds.

    Science.gov (United States)

    Lloyd, G T; Bapst, D W; Friedman, M; Davis, K E

    2016-11-01

    Branch lengths-measured in character changes-are an essential requirement of clock-based divergence estimation, regardless of whether the fossil calibrations used represent nodes or tips. However, a separate set of divergence time approaches are typically used to date palaeontological trees, which may lack such branch lengths. Among these methods, sophisticated probabilistic approaches have recently emerged, in contrast with simpler algorithms relying on minimum node ages. Here, using a novel phylogenetic hypothesis for Mesozoic dinosaurs, we apply two such approaches to estimate divergence times for: (i) Dinosauria, (ii) Avialae (the earliest birds) and (iii) Neornithes (crown birds). We find: (i) the plausibility of a Permian origin for dinosaurs to be dependent on whether Nyasasaurus is the oldest dinosaur, (ii) a Middle to Late Jurassic origin of avian flight regardless of whether Archaeopteryx or Aurornis is considered the first bird and (iii) a Late Cretaceous origin for Neornithes that is broadly congruent with other node- and tip-dating estimates. Demonstrating the feasibility of probabilistic time-scaling further opens up divergence estimation to the rich histories of extinct biodiversity in the fossil record, even in the absence of detailed character data. © 2016 The Authors.

  11. Study on bird's & insect's wing aerodynamics and comparison of its analytical value with standard airfoil

    Science.gov (United States)

    Ali, Md. Nesar; Alam, Mahbubul; Hossain, Md. Abed; Ahmed, Md. Imteaz

    2017-06-01

    Flight is the main mode of locomotion used by most of the world's bird & insect species. This article discusses the mechanics of bird flight, with emphasis on the varied forms of bird's & insect's wings. The fundamentals of bird flight are similar to those of aircraft. Flying animals flap their wings to generate lift and thrust as well as to perform remarkable maneuvers with rapid accelerations and decelerations. Insects and birds provide illuminating examples of unsteady aerodynamics. Lift force is produced by the action of air flow on the wing, which is an airfoil. The airfoil is shaped such that the air provides a net upward force on the wing, while the movement of air is directed downward. Additional net lift may come from airflow around the bird's & insect's body in some species, especially during intermittent flight while the wings are folded or semi-folded. Bird's & insect's flight in nature are sub-divided into two stages. They are Unpowered Flight: Gliding and Soaring & Powered Flight: Flapping. When gliding, birds and insects obtain both a vertical and a forward force from their wings. When a bird & insect flaps, as opposed to gliding, its wings continue to develop lift as before, but the lift is rotated forward to provide thrust, which counteracts drag and increases its speed, which has the effect of also increasing lift to counteract its weight, allowing it to maintain height or to climb. Flapping flight is more complicated than flight with fixed wings because of the structural movement and the resulting unsteady fluid dynamics. Flapping involves two stages: the down-stroke, which provides the majority of the thrust, and the up-stroke, which can also (depending on the bird's & insect's wings) provide some thrust. Most kinds of bird & insect wing can be grouped into four types, with some falling between two of these types. These types of wings are elliptical wings, high speed wings, high aspect ratio wings and soaring wings with slots. Hovering is used

  12. Migration strategy affects avian influenza dynamics in mallards (Anas platyrhynchos).

    Science.gov (United States)

    Takekawa, John Y.; Hill, Nichola J.; Ackerman, Joshua T.; Herring, Garth; Hobson, Keith; Cardona, Carol J.; Runstadler, Jonathan; Boyce, Walter M.

    2012-01-01

    Studies of pathogen transmission typically overlook that wildlife hosts can include both migrant and resident populations when attempting to model circulation. Through the application of stable isotopes in flight feathers, we estimated the migration strategy of mallards (Anas platyrhynchos) occurring on California wintering grounds. Our study demonstrates that mallards- a principal host of avian influenza virus (AIV) in nature, contribute differently to virus gene flow depending on migration strategy. No difference in AIV prevalence was detected between resident (9.6%), intermediate-distance (9.6%) and long-distance migrants (7.4%). Viral diversity among the three groups was also comparable, possibly owing to viral pool mixing when birds converge at wetlands during winter. However, migrants and residents contributed differently to the virus gene pool at wintering wetlands. Migrants introduced virus from northern breeding grounds (Alaska and the NW Pacific Rim) into the wintering population, facilitating gene flow at continental scales, but circulation of imported virus appeared to be limited. In contrast, resident mallards acted as AIV reservoirs facilitating year-round circulation of limited subtypes (i.e. H5N2) at lower latitudes. This study supports a model of virus exchange in temperate regions driven by the convergence of wild birds with separate geographic origins and exposure histories.

  13. Flower power: tree flowering phenology as a settlement cue for migrating birds.

    Science.gov (United States)

    McGrath, Laura J; van Riper, Charles; Fontaine, Joseph J

    2009-01-01

    1. Neotropical migrant birds show a clear preference for stopover habitats with ample food supplies; yet, the proximate cues underlying these decisions remain unclear. 2. For insectivorous migrants, cues associated with vegetative phenology (e.g. flowering, leaf flush, and leaf loss) may reliably predict the availability of herbivorous arthropods. Here we examined whether migrants use the phenology of five tree species to choose stopover locations, and whether phenology accurately predicts food availability. 3. Using a combination of experimental and observational evidence, we show migrant populations closely track tree phenology, particularly the flowering phenology of honey mesquite (Prosopis glandulosa), and preferentially forage in trees with more flowers. Furthermore, the flowering phenology of honey mesquite reliably predicts overall arthropod abundance as well as the arthropods preferred by migrants for food. 4. Together, these results suggest that honey mesquite flowering phenology is an important cue used by migrants to assess food availability quickly and reliably, while in transit during spring migration.

  14. The effect of the Sep wind park near Oosterbierum, Friesland, The Netherlands, on birds

    International Nuclear Information System (INIS)

    Winkelman, J.E.

    1992-01-01

    The title study concerns the period 1984-1991. The wind park consists of 18 three-bladed 300 kW horizontal axis wind turbines of 35 meters height, and a rotor diameter of 30 meters, seven meteorological towers, and three cluster and control buildings. Aspects studied included disturbance of breeding, resting or feeding, and migrating birds, behavior of birds approaching the wind turbines during the day and night, and bird victims due to collision with the wind turbines and the meteorological towers. In this report attention is paid to the disturbance of the bird's biotope. The results show that four species of grassland birds, breeding in the park, were hardly disturbed by the wind turbines. For feeding and resting birds, however, disturbance effects were noted, even at a distance of 500 meters from the outside wind turbine array. The present number of bird species reduced 60-95%, dependent on the species, after the wind park was put into operation. Also the behavior of migrating birds was influenced by the wind park, showed in clustering of groups or avoiding the wind park, sometimes up to 67% of the birds did so. It is therefore recommended not to implement new wind parks in important bird migration and bird feeding or bird resting areas. Bird popular areas, however, are mostly windy areas. 15 figs., 25 tabs., 56 app., 128 refs

  15. Concealed by darkness: interactions between predatory bats and nocturnally migrating songbirds illuminated by DNA sequencing

    OpenAIRE

    Ibáñez, Carlos; Popa-Lisseanu, Ana G.; Pastor-Beviá, David; García-Mudarra, Juan L.; Juste, Javier

    2016-01-01

    Recently, several species of aerial-hawking bats have been found to prey on migrating songbirds, but details on this behaviour and its relevance for bird migration are still unclear. We sequenced avian DNA in feather-containing scats of the bird-feeding bat Nyctalus lasiopterus from Spain collected during bird migration seasons. We found very high prey diversity, with 31 bird species from eight families of Passeriformes, almost all of which were nocturnally flying sub-Saharan migrants. Moreov...

  16. A Physics-Inspired Mechanistic Model of Migratory Movement Patterns in Birds.

    Science.gov (United States)

    Revell, Christopher; Somveille, Marius

    2017-08-29

    In this paper, we introduce a mechanistic model of migratory movement patterns in birds, inspired by ideas and methods from physics. Previous studies have shed light on the factors influencing bird migration but have mainly relied on statistical correlative analysis of tracking data. Our novel method offers a bottom up explanation of population-level migratory movement patterns. It differs from previous mechanistic models of animal migration and enables predictions of pathways and destinations from a given starting location. We define an environmental potential landscape from environmental data and simulate bird movement within this landscape based on simple decision rules drawn from statistical mechanics. We explore the capacity of the model by qualitatively comparing simulation results to the non-breeding migration patterns of a seabird species, the Black-browed Albatross (Thalassarche melanophris). This minimal, two-parameter model was able to capture remarkably well the previously documented migration patterns of the Black-browed Albatross, with the best combination of parameter values conserved across multiple geographically separate populations. Our physics-inspired mechanistic model could be applied to other bird and highly-mobile species, improving our understanding of the relative importance of various factors driving migration and making predictions that could be useful for conservation.

  17. Bats on a Budget: Torpor-Assisted Migration Saves Time and Energy

    Science.gov (United States)

    McGuire, Liam P.; Jonasson, Kristin A.; Guglielmo, Christopher G.

    2014-01-01

    Bats and birds must balance time and energy budgets during migration. Migrating bats face similar physiological challenges to birds, but nocturnality creates special challenges for bats, such as a conflict between travelling and refueling, which many birds avoid by feeding in daylight and flying at night. As endothermic animals, bats and birds alike must expend substantial amounts of energy to maintain high body temperatures. For migratory birds refueling at stopovers, remaining euthermic during inactive periods reduces the net refuelling rate, thereby prolonging stopover duration and delaying subsequent movement. We hypothesized that bats could mitigate similar ambient-temperature dependent costs by using a torpor-assisted migration strategy. We studied silver-haired bats Lasionycteris noctivagans during autumn migration using a combination of respirometry and temperature-sensitive radiotelemetry to estimate energy costs incurred under ambient temperature conditions, and the energy that bats saved by using torpor during daytime roosting periods. All bats, regardless of sex, age, or body condition used torpor at stopover and saved up to 91% of the energy they would have expended to remain euthermic. Furthermore, bats modulated use of torpor depending on ambient temperature. By adjusting the time spent torpid, bats achieved a rate of energy expenditure independent of the ambient temperature encountered at stopover. By lowering body temperature during inactive periods, fuel stores are spared, reducing the need for refuelling. Optimal migration models consider trade-offs between time and energy. Heterothermy provides a physiological strategy that allows bats to conserve energy without paying a time penalty as they migrate. Although uncommon, some avian lineages are known to use heterothermy, and current theoretical models of migration may not be appropriate for these groups. We propose that thermoregulatory strategies should be an important consideration of future

  18. Bird impact study on the 10 MW wind farm of La Pena (Tarifa)

    International Nuclear Information System (INIS)

    Cererols, N.; Martinez, A.; Ferrer, M.

    1996-01-01

    This paper shows the conclusions of a 16 month study of the possible impacts on the local and migrating population of birds of a wind farm located in the passageway of migrating birds between Africa and Europe. On the whole, the wind farm did not prove to represent an important impact on the birds present in its surroundings and, on the contrary, created a new habitat for some species not present in adjacent areas. (author)

  19. Wind effects on the migration routes of trans-Saharan soaring raptors: geographical, seasonal, and interspecific variation

    Science.gov (United States)

    Vidal-Mateo, Javier; Mellone, Ugo; López-López, Pascual; La Puente, Javier De; García-Ripollés, Clara; Bermejo, Ana; Urios, Vicente

    2016-01-01

    Abstract Wind is among the most important environmental factors shaping birds’ migration patterns. Birds must deal with the displacement caused by crosswinds and their behavior can vary according to different factors such as flight mode, migratory season, experience, and distance to goal areas. Here we analyze the relationship between wind and migratory movements of three raptor species which migrate by soaring–gliding flight: Egyptian vulture Neophron percnopterus, booted eagle Aquila pennata, and short-toed snake eagle Circaetus gallicus. We analyzed daily migratory segments (i.e., the path joining consecutive roosting locations) using data recorded by GPS satellite telemetry. Daily movements of Egyptian vultures and booted eagles were significantly affected by tailwinds during both autumn and spring migrations. In contrast, daily movements of short-toed eagles were only significantly affected by tailwinds during autumn migration. The effect of crosswinds was significant in all cases. Interestingly, Egyptian vultures and booted eagles showed latitudinal differences in their behavior: both species compensated more frequently at the onset of autumn migration and, at the end of the season when reaching their wintering areas, the proportion of drift segments was higher. In contrast, there was a higher drift at the onset of spring migration and a higher compensation at the end. Our results highlight the effect of wind patterns on the migratory routes of soaring raptors, with different outcomes in relation to species, season, and latitude, ultimately shaping the loop migration patterns that current tracking techniques are showing to be widespread in many long distance migrants. PMID:29491895

  20. Southward migration and fuel deposition of Red Knots Calidris canutus

    OpenAIRE

    Helseth, Anders; Lindström, Åke; Stervander, Martin

    2005-01-01

    We compared the differences between spring and autumn in migration speed, fuelling rates and fuel loads of migrating Red Knots Calidris canutus. As a basis we used ringing data from Ottenby Bird Observatory, southeastern Sweden, collected 1948–2003, with morphometrical data from 1990–2003. Numbers ringed varied between 0 and 301 per year (average 56). Morphometrics, recoveries and recaptures of ringed birds indicated that most birds belonged to the Afro-Siberian subspecies C. c. canutus, poss...

  1. Hyalomma ticks on northward migrating birds in southern Spain: Implications for the risk of entry of Crimean-Congo haemorrhagic fever virus to Great Britain.

    Science.gov (United States)

    England, Marion E; Phipps, Paul; Medlock, Jolyon M; Atkinson, Peter M; Atkinson, Barry; Hewson, Roger; Gale, Paul

    2016-06-01

    Crimean-Congo haemorrhagic fever virus (CCHFV) is a zoonotic virus transmitted by Hyalomma ticks, the immature stages of which may be carried by migratory birds. In this study, a total of 12 Hyalomma ticks were recovered from five of 228 migratory birds trapped in Spring, 2012 in southern Spain along the East Atlantic flyway. All collected ticks tested negative for CCHFV. While most birds had zero Hyalomma ticks, two individuals had four and five ticks each and the statistical distribution of Hyalomma tick counts per bird is over-dispersed compared to the Poisson distribution, demonstrating the need for intensive sampling studies to avoid underestimating the total number of ticks. Rates of tick exchange on migratory birds during their northwards migration will affect the probability that a Hyalomma tick entering Great Britain is positive for CCHFV. Drawing on published data, evidence is presented that the latitude of a European country affects the probability of entry of Hyalomma ticks on wild birds. Further data on Hyalomma infestation rates and tick exchange rates are required along the East Atlantic flyway to further our understanding of the origin of Hyalomma ticks (i.e., Africa or southern Europe) and hence the probability of entry of CCHFV into GB. © 2016 The Society for Vector Ecology.

  2. Bat flight: aerodynamics, kinematics and flight morphology.

    Science.gov (United States)

    Hedenström, Anders; Johansson, L Christoffer

    2015-03-01

    Bats evolved the ability of powered flight more than 50 million years ago. The modern bat is an efficient flyer and recent research on bat flight has revealed many intriguing facts. By using particle image velocimetry to visualize wake vortices, both the magnitude and time-history of aerodynamic forces can be estimated. At most speeds the downstroke generates both lift and thrust, whereas the function of the upstroke changes with forward flight speed. At hovering and slow speed bats use a leading edge vortex to enhance the lift beyond that allowed by steady aerodynamics and an inverted wing during the upstroke to further aid weight support. The bat wing and its skeleton exhibit many features and control mechanisms that are presumed to improve flight performance. Whereas bats appear aerodynamically less efficient than birds when it comes to cruising flight, they have the edge over birds when it comes to manoeuvring. There is a direct relationship between kinematics and the aerodynamic performance, but there is still a lack of knowledge about how (and if) the bat controls the movements and shape (planform and camber) of the wing. Considering the relatively few bat species whose aerodynamic tracks have been characterized, there is scope for new discoveries and a need to study species representing more extreme positions in the bat morphospace. © 2015. Published by The Company of Biologists Ltd.

  3. Innovative Visualizations Shed Light on Avian Nocturnal Migration.

    Directory of Open Access Journals (Sweden)

    Judy Shamoun-Baranes

    Full Text Available Globally, billions of flying animals undergo seasonal migrations, many of which occur at night. The temporal and spatial scales at which migrations occur and our inability to directly observe these nocturnal movements makes monitoring and characterizing this critical period in migratory animals' life cycles difficult. Remote sensing, therefore, has played an important role in our understanding of large-scale nocturnal bird migrations. Weather surveillance radar networks in Europe and North America have great potential for long-term low-cost monitoring of bird migration at scales that have previously been impossible to achieve. Such long-term monitoring, however, poses a number of challenges for the ornithological and ecological communities: how does one take advantage of this vast data resource, integrate information across multiple sensors and large spatial and temporal scales, and visually represent the data for interpretation and dissemination, considering the dynamic nature of migration? We assembled an interdisciplinary team of ecologists, meteorologists, computer scientists, and graphic designers to develop two different flow visualizations, which are interactive and open source, in order to create novel representations of broad-front nocturnal bird migration to address a primary impediment to long-term, large-scale nocturnal migration monitoring. We have applied these visualization techniques to mass bird migration events recorded by two different weather surveillance radar networks covering regions in Europe and North America. These applications show the flexibility and portability of such an approach. The visualizations provide an intuitive representation of the scale and dynamics of these complex systems, are easily accessible for a broad interest group, and are biologically insightful. Additionally, they facilitate fundamental ecological research, conservation, mitigation of human-wildlife conflicts, improvement of meteorological

  4. Concealed by darkness: interactions between predatory bats and nocturnally migrating songbirds illuminated by DNA sequencing.

    Science.gov (United States)

    Ibáñez, Carlos; Popa-Lisseanu, Ana G; Pastor-Beviá, David; García-Mudarra, Juan L; Juste, Javier

    2016-10-01

    Recently, several species of aerial-hawking bats have been found to prey on migrating songbirds, but details on this behaviour and its relevance for bird migration are still unclear. We sequenced avian DNA in feather-containing scats of the bird-feeding bat Nyctalus lasiopterus from Spain collected during bird migration seasons. We found very high prey diversity, with 31 bird species from eight families of Passeriformes, almost all of which were nocturnally flying sub-Saharan migrants. Moreover, species using tree hollows or nest boxes in the study area during migration periods were not present in the bats' diet, indicating that birds are solely captured on the wing during night-time passage. Additional to a generalist feeding strategy, we found that bats selected medium-sized bird species, thereby assumingly optimizing their energetic cost-benefit balance and injury risk. Surprisingly, bats preyed upon birds half their own body mass. This shows that the 5% prey to predator body mass ratio traditionally assumed for aerial hunting bats does not apply to this hunting strategy or even underestimates these animals' behavioural and mechanical abilities. Considering the bats' generalist feeding strategy and their large prey size range, we suggest that nocturnal bat predation may have influenced the evolution of bird migration strategies and behaviour. © 2016 John Wiley & Sons Ltd.

  5. Birds and wind power. Result report 1977-1982; Faglar och Vindkraft. Resultatrapport 1977-1982

    Energy Technology Data Exchange (ETDEWEB)

    Karlsson, Johnny

    1983-02-15

    Two large-scaled aerogenerators were erected in Sweden in 1980-82. Questions about how birds react on the generators were raised early. Theoretical calculations about the risk for collisions between migrating birds and the generators, together with data on the bird collision frequencies at radio- and television towers in Sweden were presented in a report in 1978. It was assumed that the collision frequency will normally not exceed five birds per night during nights with normal traffic rate of migrating birds, and with maximum of about 50 birds on special occasions (few cases per season). In 1979-1982 the local breeding bird fauna was censused in the immediate vicinities of the sites (arable land and grazed bushland) where the aerogenerators has been erected. The results obtained so far, do not indicate any effect at all on species diversity or abundance when comparing the situation before and after the erection of the arerogenerators. Some species have successfully colonized the areas, obviously exploiting resources created by the building activities. Two such species are Oenanthe oenanthe and Delichon urbica. Reactions of migrating birds when passing close to the generators will be studied in the nearest future (autumn 1983) when the plants will be in continous work.

  6. Seasonal variation in diversity and abundance of understorey birds ...

    African Journals Online (AJOL)

    Our findings suggest that in a situation where there is no natural forest, an exotic plantation with suitable indigenous understorey cover can help in protection of birds, including endemic and near-endemic species. Keywords: birds, conservation, Eastern Arc Mountains, plantation, seasonal altitudinal migration, seasons, ...

  7. A Comparative Study of Species Diversity of Migrant Birds Between ...

    African Journals Online (AJOL)

    stop migration. Despite Hadejia-Nguru Wetlands (Ramsar site) being an important wintering ground for migratory birds, little is known about the diversity while density is completely lacking. This study assessed the status of migratory birds in the ...

  8. Developing high-resolution spatial data of migration corridors for avian species of concern in regions of high potential wind development

    Energy Technology Data Exchange (ETDEWEB)

    Katzner, Todd [West Virginia Univ., Morgantown, WV (United States)

    2014-06-15

    The future of the US economy, our national security, and our environmental quality all depend on decreasing our reliance on foreign oil and on fossil fuels. An essential component of decreasing this reliance is the development of alternative energy sources. Wind power is among the most important alternative energy sources currently available, and the mid-Atlantic region is a primary focus for wind power development. In addition to being important to the development of wind power, the mid-Atlantic region holds a special responsibility for the conservation of the eastern North America's golden eagles (Aquila chrysaetos). This small population breeds in northeastern Canada, winters in the southern Appalachians, and nearly all of these birds pass through the mid-Atlantic region twice each year. Movement of these birds is not random and, particularly during spring and autumn, migrating golden eagles concentrate in a narrow 30-50 mile wide corridor in central Pennsylvania. Thus, because the fate of these rare birds may depend on responsible management of the habitat they use it is critical to use research to identify ways to mitigate prospective impacts on this and similar raptor species. The goal of this project was to develop high-resolution spatial risk maps showing migration corridors of and habitat use by eastern golden eagles in regions of high potential for wind development. To accomplish this, we first expanded existing models of raptor migration for the eastern USA to identify broad-scale migration patterns. We then used data from novel high-resolution tracking devices to discover routes of passage and detailed flight behavior of individual golden eagles throughout the eastern USA. Finally, we integrated these data and models to predict population-level migration patterns and individual eagle flight behavior on migration. We then used this information to build spatially explicit, probabilistic maps showing relative risk to birds from wind development. This

  9. Annual spatiotemporal migration schedules in three larger insectivorous birds

    DEFF Research Database (Denmark)

    Jacobsen, Lars Bo; Jensen, Niels Odder; Willemoes, Mikkel

    2017-01-01

    Background: Knowledge of spatiotemporal migration patterns is important for our understanding of migration ecology and ultimately conservation of migratory species. We studied the annual migration schedules of European nightjar, a large nocturnal insectivore and compared it with two other larger ...

  10. Investigations of migratory birds during operation of Horns Rev offshore wind farm. Annual status report 2004

    Energy Technology Data Exchange (ETDEWEB)

    Kjaer Christensen, T.; Hounisen, J.P. [NERI, Dept. of Wildlife Ecology and Biodiversity, Roskilde (Denmark)

    2005-07-01

    The aim of the project is to assess the collision risk between birds and wind turbines at the Horns Rev wind farm. The study focused on describing bird movements in relation to the wind farm and to identify the species-specific behavioural responses towards the wind turbines shown by migrating and staging bird species. The study was based on data from spring 2004. The Horns Rev area lies in a region known to be of importance for substantial water bird migration as well as holding internationally important numbers of several wintering and staging water bird species. (au)

  11. Investigations of migratory birds during operation of Horns Rev offshore wind farm. Annual status report 2004

    International Nuclear Information System (INIS)

    Kjaer Christensen, T.; Hounisen, J.P.

    2005-01-01

    The aim of the project is to assess the collision risk between birds and wind turbines at the Horns Rev wind farm. The study focused on describing bird movements in relation to the wind farm and to identify the species-specific behavioural responses towards the wind turbines shown by migrating and staging bird species. The study was based on data from spring 2004. The Horns Rev area lies in a region known to be of importance for substantial water bird migration as well as holding internationally important numbers of several wintering and staging water bird species. (au)

  12. Chewing lice from wild birds in northern Greece.

    Science.gov (United States)

    Diakou, Anastasia; Pedroso Couto Soares, José Bernardo; Alivizatos, Haralambos; Panagiotopoulou, Maria; Kazantzidis, Savas; Literák, Ivan; Sychra, Oldřich

    2017-10-01

    Greece represents an important area for wild birds due to its geographical position and habitat diversity. Although the bird species in Greece are well recorded, the information about the chewing lice that infest them is practically non-existent. Thus, the aim of the present study was to record the species of lice infesting wild birds in northern Greece and furthermore, to associate the infestation prevalence with factors such as the age, sex, migration and social behaviour of the host as well as the time of the year. In total 729 birds, (belonging to 9 orders, 32 families and 68 species) were examined in 7 localities of northern Greece, during 9 ringing sessions from June 2013 until October 2015. Eighty (11%) of the birds were found to be infested with lice. In 31 different bird species, 560 specimens of lice, belonging to 33 species were recorded. Mixed infestations were recorded in 11 cases where birds were infested with 2-3 different lice species. Four new host-parasite associations were recorded i.e. Menacanthus curuccae from Acrocephalus melanopogon, Menacanthus agilis from Cettia cetti, Myrsidea sp. from Acrocephalus schoenobaenus, and Philopretus citrinellae from Spinus spinus. Moreover, Menacanthus sinuatus was detected on Poecile lugubris, rendering this report the first record of louse infestation in this bird species. The statistical analysis of the data collected showed no association between parasitological parameters (prevalence, mean and median intensity and mean abundance) in two different periods of the year (breeding vs post-breeding season). However, there was a statistically significant difference in the prevalence of infestation between a) migrating and sedentary passerine birds (7.4% vs 13.2%), b) colonial and territorial birds (54.5% vs 9.6%), and c) female and male birds in breeding period (2.6% vs 15.6%). Copyright © 2017. Published by Elsevier B.V.

  13. Field Flight Dynamics of Hummingbirds during Territory Encroachment and Defense.

    Directory of Open Access Journals (Sweden)

    Katherine M Sholtis

    Full Text Available Hummingbirds are known to defend food resources such as nectar sources from encroachment by competitors (including conspecifics. These competitive intraspecific interactions provide an opportunity to quantify the biomechanics of hummingbird flight performance during ecologically relevant natural behavior. We recorded the three-dimensional flight trajectories of Ruby-throated Hummingbirds defending, being chased from and freely departing from a feeder. These trajectories allowed us to compare natural flight performance to earlier laboratory measurements of maximum flight speed, aerodynamic force generation and power estimates. During field observation, hummingbirds rarely approached the maximal flight speeds previously reported from wind tunnel tests and never did so during level flight. However, the accelerations and rates of change in kinetic and potential energy we recorded indicate that these hummingbirds likely operated near the maximum of their flight force and metabolic power capabilities during these competitive interactions. Furthermore, although birds departing from the feeder while chased did so faster than freely-departing birds, these speed gains were accomplished by modulating kinetic and potential energy gains (or losses rather than increasing overall power output, essentially trading altitude for speed during their evasive maneuver. Finally, the trajectories of defending birds were directed toward the position of the encroaching bird rather than the feeder.

  14. Field Flight Dynamics of Hummingbirds during Territory Encroachment and Defense.

    Science.gov (United States)

    Sholtis, Katherine M; Shelton, Ryan M; Hedrick, Tyson L

    2015-01-01

    Hummingbirds are known to defend food resources such as nectar sources from encroachment by competitors (including conspecifics). These competitive intraspecific interactions provide an opportunity to quantify the biomechanics of hummingbird flight performance during ecologically relevant natural behavior. We recorded the three-dimensional flight trajectories of Ruby-throated Hummingbirds defending, being chased from and freely departing from a feeder. These trajectories allowed us to compare natural flight performance to earlier laboratory measurements of maximum flight speed, aerodynamic force generation and power estimates. During field observation, hummingbirds rarely approached the maximal flight speeds previously reported from wind tunnel tests and never did so during level flight. However, the accelerations and rates of change in kinetic and potential energy we recorded indicate that these hummingbirds likely operated near the maximum of their flight force and metabolic power capabilities during these competitive interactions. Furthermore, although birds departing from the feeder while chased did so faster than freely-departing birds, these speed gains were accomplished by modulating kinetic and potential energy gains (or losses) rather than increasing overall power output, essentially trading altitude for speed during their evasive maneuver. Finally, the trajectories of defending birds were directed toward the position of the encroaching bird rather than the feeder.

  15. Disease dynamics and bird migration--linking mallards Anas platyrhynchos and subtype diversity of the influenza A virus in time and space.

    Directory of Open Access Journals (Sweden)

    Gunnar Gunnarsson

    Full Text Available The mallard Anas platyrhynchos is a reservoir species for influenza A virus in the northern hemisphere, with particularly high prevalence rates prior to as well as during its prolonged autumn migration. It has been proposed that the virus is brought from the breeding grounds and transmitted to conspecifics during subsequent staging during migration, and so a better understanding of the natal origin of staging ducks is vital to deciphering the dynamics of viral movement pathways. Ottenby is an important stopover site in southeast Sweden almost halfway downstream in the major Northwest European flyway, and is used by millions of waterfowl each year. Here, mallards were captured and sampled for influenza A virus infection, and positive samples were subtyped in order to study possible links to the natal area, which were determined by a novel approach combining banding recovery data and isotopic measurements (δ(2H of feathers grown on breeding grounds. Geographic assignments showed that the core natal areas of studied mallards were in Estonia, southern and central Finland, and northwestern Russia. This study demonstrates a clear temporal succession of latitudes of natal origin during the course of autumn migration. We also demonstrate a corresponding and concomitant shift in virus subtypes. Acknowledging that these two different patterns were based in part upon different data, a likely interpretation worth further testing is that the early arriving birds with more proximate origins have different influenza A subtypes than the more distantly originating late autumn birds. If true, this knowledge would allow novel insight into the origins and transmission of the influenza A virus among migratory hosts previously unavailable through conventional approaches.

  16. The effect of the Sep wind park near Oosterbierum, Friesland, The Netherlands, on birds. De invloed van de Sep-proefwindcentrale te Oosterbierum (Friesland) op vogels; Deel 2: Nachtelijke aanvaringskansen

    Energy Technology Data Exchange (ETDEWEB)

    Winkelman, J E

    1992-01-01

    The title study concerns the period 1984-1991. The wind park consists of 18 three-bladed 300 kW horizontal axis wind turbines of 35 meters height, and a rotor diameter of 30 meters, seven meteorological towers, and three cluster and control buildings. Aspects studied included disturbance of breeding, resting or feeding, and migrating birds, behavior of birds approaching the wind turbines during the day and night, and bird victims due to collision with the wind turbines and the meteorological towers. In this report data on the number of birds passing the wind park at night and the flight behavior of these birds during their passage are presented and discussed. The numbers were determined in the period 1985-1988 by using a search approach radar, two passive image intensifiers in combination with infrared spot lights, and a thermal image intensifier. Illumination of the wind turbines to avoid collisions is not believed to be necessary, because birds seem to be quite good at spotting the wind turbines, even during conditions of moderate visibility at night. 30 figs., 23 tabs., 18 app., 109 refs.

  17. Webcams for Bird Detection and Monitoring: A Demonstration Study

    Directory of Open Access Journals (Sweden)

    Willem W. Verstraeten

    2010-04-01

    Full Text Available Better insights into bird migration can be a tool for assessing the spread of avian borne infections or ecological/climatologic issues reflected in deviating migration patterns. This paper evaluates whether low budget permanent cameras such as webcams can offer a valuable contribution to the reporting of migratory birds. An experimental design was set up to study the detection capability using objects of different size, color and velocity. The results of the experiment revealed the minimum size, maximum velocity and contrast of the objects required for detection by a standard webcam. Furthermore, a modular processing scheme was proposed to track and follow migratory birds in webcam recordings. Techniques such as motion detection by background subtraction, stereo vision and lens distortion were combined to form the foundation of the bird tracking algorithm. Additional research to integrate webcam networks, however, is needed and future research should enforce the potential of the processing scheme by exploring and testing alternatives of each individual module or processing step.

  18. Avian influenza virus wild bird surveillance in the Azov and Black Sea regions of Ukraine

    Science.gov (United States)

    The Azov and Black Sea basins are transcontinental migration routes of wild birds from Northern Asia and Europe to the Mediterranean, Africa and Southwest Asia. These regions constitute an area of transit, stops during migration, and nesting of many migratory bird species with a very high level of ...

  19. Forelimb posture in dinosaurs and the evolution of the avian flapping flight-stroke.

    Science.gov (United States)

    Nudds, Robert L; Dyke, Gareth J

    2009-04-01

    Ontogenetic and behavioral studies using birds currently do not document the early evolution of flight because birds (including juveniles) used in such studies employ forelimb oscillation frequencies over 10 Hz, forelimb stroke-angles in excess of 130 degrees , and possess uniquely avian flight musculatures. Living birds are an advanced morphological stage in the development of flapping flight. To gain insight into the early stages of flight evolution (i.e., prebird), in the absence of a living analogue, a new approach using Strouhal number was used. Strouhal number is a nondimensional number that describes the relationship between wing-stroke amplitude (A), wing-beat frequency (f), and flight speed (U). Calculations indicated that even moderate wing movements are enough to generate rudimentary thrust and that a propulsive flapping flight-stroke could have evolved via gradual incremental changes in wing movement and wing morphology. More fundamental to the origin of the avian flapping flight-stroke is the question of how a symmetrical forelimb posture-required for gliding and flapping flight-evolved from an alternating forelimb motion, evident in all extant bipeds when running except birds.

  20. The wings before the bird: an evaluation of flapping-based locomotory hypotheses in bird antecedents

    Directory of Open Access Journals (Sweden)

    T. Alexander Dececchi

    2016-07-01

    Full Text Available Background: Powered flight is implicated as a major driver for the success of birds. Here we examine the effectiveness of three hypothesized pathways for the evolution of the flight stroke, the forelimb motion that powers aerial locomotion, in a terrestrial setting across a range of stem and basal avians: flap running, Wing Assisted Incline Running (WAIR, and wing-assisted leaping. Methods: Using biomechanical mathematical models based on known aerodynamic principals and in vivo experiments and ground truthed using extant avians we seek to test if an incipient flight stroke may have contributed sufficient force to permit flap running, WAIR, or leaping takeoff along the phylogenetic lineage from Coelurosauria to birds. Results: None of these behaviours were found to meet the biomechanical threshold requirements before Paraves. Neither was there a continuous trend of refinement for any of these biomechanical performances across phylogeny nor a signal of universal applicability near the origin of birds. None of these flap-based locomotory models appear to have been a major influence on pre-flight character acquisition such as pennaceous feathers, suggesting non-locomotory behaviours, and less stringent locomotory behaviours such as balancing and braking, played a role in the evolution of the maniraptoran wing and nascent flight stroke. We find no support for widespread prevalence of WAIR in non-avian theropods, but can’t reject its presence in large winged, small-bodied taxa like Microraptor and Archaeopteryx. Discussion: Using our first principles approach we find that “near flight” locomotor behaviors are most sensitive to wing area, and that non-locomotory related selection regimes likely expanded wing area well before WAIR and other such behaviors were possible in derived avians. These results suggest that investigations of the drivers for wing expansion and feather elongation in theropods need not be intrinsically linked to locomotory

  1. The Netherlands Bird Avoidance Model, Final Report

    NARCIS (Netherlands)

    Shamoun-Baranes, J.; Bouten, W.; Sierdsema, H.; van Belle, J.; van Gasteren, J.R.; van Loon, E.E.

    2006-01-01

    The NL-BAM was developed as a web-based decision support tool to be used by the bird hazard avoidance experts in the ecology unit of the Royal Netherlands Air Force. The NL-BAM will be used together with the ROBIN 4 radar system to provide BirdTAMS, for real time warnings and flight planning and to

  2. Population specific migration patterns of an European-Afrotropical songbird

    DEFF Research Database (Denmark)

    Pedersen, Lykke; Tøttrup, Anders P.; Thorup, Kasper

    Every year, billions of songbirds migrate thousands of kilometres between the European and African continent. The fascinating behaviour of migration that we are witnessing today is assumed to have evolved through a series of dispersal events from Africa into Europe since the last glaciation period....... Recent technological advances are currently enabling us to track yet smaller songbirds throughout their migration cycle providing valuable insight into the life cycle of individual birds. However, direct tracking of migratory birds has so far mainly been conducted on single populations and our...... understanding of entire species migration systems is thus still limited. In this project we analyse the spatio-temporal migration schedule of Red-backed Shrikes, Lanius collurio, using tracking data from individuals originating from geographically distinct breeding populations (Scandinavia, the Netherlands...

  3. Data Mining Approaches for Habitats and Stopovers Discovery of Migratory Birds

    Directory of Open Access Journals (Sweden)

    Qiang Xu

    2013-03-01

    Full Text Available This paper focuses on using data mining technology to efficiently and accurately discover habitats and stopovers of migratory birds. The three methods we used are as follows: 1. a density-based clustering method, detecting stopovers of birds during their migration through density-based clustering of location points; 2. A location histories parser method, detecting areas that have been overstayed by migratory birds during a set time period by setting time and distance thresholds; and 3. A time-parameterized line segment clustering method, clustering directed line segments to analyze shared segments of migratory pathways of different migratory birds and discover the habitats and stopovers of these birds. Finally, we analyzed the migration data of the bar-headed goose in the Qinghai Lake Area through the three above methods and verified the effectiveness of the three methods and, by comparison, identified the scope and context of the use of these three methods respectively.

  4. Dispersal and migration

    Directory of Open Access Journals (Sweden)

    Schwarz, C.

    2004-06-01

    Full Text Available Ringing of birds unveiled many aspects of avian migration and dispersal movements. However, there is even much more to be explored by the use of ringing and other marks. Dispersal is crucial in understanding the initial phase of migration in migrating birds as it is to understand patterns and processes of distribution and gene flow. So far, the analysis of migration was largely based on analysing spatial and temporal patters of recoveries of ringed birds. However, there are considerable biases and pitfalls in using recoveries due to spatial and temporal variation in reporting probabilities. Novel methods are required for future studies separating the confounding effects of spatial and temporal heterogeneity of recovery data and heterogeneity of the landscape as well. These novel approaches should aim a more intensive and novel use of the existing recovery data by taking advantage of, for instance, dynamic and multistate modeling, should elaborate schemes for future studies, and should also include other marks that allow a more rapid data collection, like telemetry, geolocation and global positioning systems, and chemical and molecular markers. The latter appear to be very useful in the delineating origin of birds and connectivity between breeding and non–breeding grounds. Many studies of migration are purely descriptive. However, King and Brooks (King & Brooks, 2004 examine if movement patterns of dolphins change after the introduction of a gillnet ban. Bayesian methods are an interesting approach to this problem as they provide a meaningful measure of the probability that such a change occurred rather than simple yes/no response that is often the result of classical statistical methods. However, the key difficulty of a general implementation of Bayesian methods is the complexity of the modelling —there is no general userfriendly package that is easily accessible to most scientists. Drake and Alisauskas (Drake & Alisauskas, 2004 examine the

  5. Active migration is associated with specific and consistent changes to gut microbiota in Calidris shorebirds.

    Science.gov (United States)

    Risely, Alice; Waite, David W; Ujvari, Beata; Hoye, Bethany J; Klaassen, Marcel

    2018-03-01

    Gut microbes are increasingly recognised for their role in regulating an animal's metabolism and immunity. However, identifying repeatable associations between host physiological processes and their gut microbiota has proved challenging, in part because microbial communities often respond stochastically to host physiological stress (e.g. fasting, forced exercise or infection). Migratory birds provide a valuable system in which to test host-microbe interactions under physiological extremes because these hosts are adapted to predictable metabolic and immunological challenges as they undergo seasonal migrations, including temporary gut atrophy during long-distance flights. These physiological challenges may either temporarily disrupt gut microbial ecosystems, or, alternatively, promote predictable host-microbe associations during migration. To determine the relationship between migration and gut microbiota, we compared gut microbiota composition between migrating and non-migrating ("resident") conspecific shorebirds sharing a flock. We performed this across two sandpiper species, Calidris ferruginea and Calidris ruficollis, in north-western Australia, and an additional C. ruficollis population 3,000 km away in southern Australia. We found that migrants consistently had higher abundances of the bacterial genus Corynebacterium (average 28% abundance) compared to conspecific residents (average gut community variation when excluding Corynebacterium. Our findings suggest a consistent relationship between Corynebacterium and Calidris shorebirds during migration, with further research required to identify causal mechanisms behind the association, and to elucidate functionality to the host. However, outside this specific association, migrating shorebirds broadly maintained gut community structure, which may allow them to quickly recover gut function after a migratory flight. This study provides a rare example of a repeatable and specific response of the gut microbiota to a

  6. Determinants of spring migration departure decision in a bat.

    Science.gov (United States)

    Dechmann, Dina K N; Wikelski, M; Ellis-Soto, D; Safi, K; O'Mara, M Teague

    2017-09-01

    Migratory decisions in birds are closely tied to environmental cues and fat stores, but it remains unknown if the same variables trigger bat migration. To learn more about the rare phenomenon of bat migration, we studied departure decisions of female common noctules ( Nyctalus noctula ) in southern Germany. We did not find the fattening period that modulates departure decisions in birds. Female noctules departed after a regular evening foraging session, uniformly heading northeast. As the day of year increased, migratory decisions were based on the interactions among wind speed, wind direction and air pressure. As the migration season progressed, bats were likely to migrate on nights with higher air pressure and faster tail winds in the direction of travel, and also show high probability of migration on low-pressure nights with slow head winds. Common noctules thus monitor complex environmental conditions to find the optimal migration night. © 2017 The Authors.

  7. Using a Sound Field to Reduce the Risks of Bird-Strike: An Experimental Approach.

    Science.gov (United States)

    Swaddle, John P; Ingrassia, Nicole M

    2017-07-01

    Each year, billions of birds collide with large human-made structures, such as building, towers, and turbines, causing substantial mortality. Such bird-strike, which is projected to increase, poses risks to populations of birds and causes significant economic costs to many industries. Mitigation technologies have been deployed in an attempt to reduce bird-strike, but have been met with limited success. One reason for bird-strike may be that birds fail to pay adequate attention to the space directly in front of them when in level, cruising flight. A warning signal projected in front of a potential strike surface might attract visual attention and reduce the risks of collision. We tested this idea in captive zebra finches (Taeniopygia guttata) that were trained to fly down a long corridor and through an open wooden frame. Once birds were trained, they each experienced three treatments at unpredictable times and in a randomized order: a loud sound field projected immediately in front of the open wooden frame; a mist net (i.e., a benign strike surface) placed inside the wooden frame; and both the loud sound and the mist net. We found that birds slowed their flight approximately 20% more when the sound field was projected in front of the mist net compared with when the mist net was presented alone. This reduction in velocity would equate to a substantial reduction in the force of any collision. In addition to slowing down, birds increased the angle of attack of their body and tail, potentially allowing for more maneuverable flight. Concomitantly, the only cases where birds avoided the mist net occurred in the sound-augmented treatment. Interestingly, the sound field by itself did not demonstrably alter flight. Although our study was conducted in a limited setting, the alterations of flight associated with our sound field has implications for reducing bird-strike in nature and we encourage researchers to test our ideas in field trials. © The Author 2017. Published by

  8. Optic flow stabilizes flight in ruby-throated hummingbirds.

    Science.gov (United States)

    Ros, Ivo G; Biewener, Andrew A

    2016-08-15

    Flying birds rely on visual cues for retinal image stabilization by negating rotation-induced optic flow, the motion of the visual panorama across the retina, through corrective eye and head movements. In combination with vestibular and proprioceptive feedback, birds may also use visual cues to stabilize their body during flight. Here, we test whether artificially induced wide-field motion generated through projected visual patterns elicits maneuvers in body orientation and flight position, in addition to stabilizing vision. To test this hypothesis, we present hummingbirds flying freely within a 1.2 m cylindrical visual arena with a virtual surround rotated at different speeds about its vertical axis. The birds responded robustly to these visual perturbations by rotating their heads and bodies with the moving visual surround, and by adjusting their flight trajectories, following the surround. Thus, similar to insects, hummingbirds appear to use optic flow cues to control flight maneuvers as well as to stabilize their visual inputs. © 2016. Published by The Company of Biologists Ltd.

  9. LINKING THE COMMUNITY IN THE MIGRATORY RAPTOR BIRDS COUNTS (BIRDS: FALCONIFORM IN EASTERN CUBA

    Directory of Open Access Journals (Sweden)

    Naylien Barreda-Leyva

    2010-09-01

    Full Text Available Through interviews, workshops, conferences and sociocultural meeting, is carried out the linking of three communities from the high area of Gran Piedra to the studies and counts of migratory raptors birds developed in the east of Cuba. These small communities are near to one of the two points of count of migratory raptors of the region. During the interviews we could verify that some residents possessed basic knowledge on the raptors birds, but didn't know about the migration of these birds. 100 % of the interviewees coincided in that the main local problematic is the loss of birds of pen due to the attack of raptors, specifically the endemic Cuban threatened Accipitter gundlachi. The workshops were able to create spaces of exchange and reflection about the importance of the raptor’s conservation in the region. This linkage of cooperation and increasing awareness, allow an approaching between the communitarians and the researchers and volunteers that work in the counts of raptor birds in Cuba and the feedback of the scientific knowledge with the popular knowledge.

  10. Flight Paths of Migrating Golden Eagles and the Risk Associated with Wind Energy Development in the Rocky Mountains

    Directory of Open Access Journals (Sweden)

    Naira N. Johnston

    2013-12-01

    Full Text Available In recent years, the eastern foothills of the Rocky Mountains in northeastern British Columbia have received interest as a site of industrial wind energy development but, simultaneously, have been the subject of concern about wind development coinciding with a known migratory corridor of Golden Eagles (Aquila chrysaetos. We tracked and quantified eagle flights that crossed or followed ridgelines slated for one such wind development. We found that hourly passage rates during fall migration peaked at midday and increased by 17% with each 1 km/h increase in wind speed and by 11% with each 1°C increase in temperature. The propensity to cross the ridge tops where turbines would be situated differed between age classes, with juvenile eagles almost twice as likely to traverse the ridge-top area as adults or subadults. During fall migration, Golden Eagles were more likely to cross ridges at turbine heights (risk zone, < 150 m above ground under headwinds or tailwinds, but this likelihood decreased with increasing temperature. Conversely, during spring migration, eagles were more likely to move within the ridge-top area under eastern crosswinds. Identifying Golden Eagle flight routes and altitudes with respect to major weather systems and local topography in the Rockies may help identify scenarios in which the potential for collisions is greatest at this and other installations.

  11. Avian influenza virus wild bird surveillance in the Azov and Black Sea regions of Ukraine (2010-2011)

    Science.gov (United States)

    The Azov and Black Sea basins are part of the transcontinental wild bird migration routes from Northern Asia and Europe to the Mediterranean, Africa and Southwest Asia. These regions constitute an area of transit, stops during migration, and nesting for many different bird species. From September ...

  12. a comparative study of species diversity of migrant birds between

    African Journals Online (AJOL)

    A.S RINGIM

    ABSTRACT. Among the most complex and fascinating behaviour in birds is their long, non-stop migration. Despite Hadejia-Nguru Wetlands (Ramsar site) being an important wintering ground for migratory birds, little is known about the diversity while density is completely lacking. This study assessed the status of migratory ...

  13. Investigation of influenza in migrating birds, the primordial reservoir and transmitters of influenza in Brazil Investigação de influenza em aves migratórias, principal reservatório e transporte de influenza no Brasil

    Directory of Open Access Journals (Sweden)

    Adélia Hiroko Nagamori Kawamoto

    2005-03-01

    Full Text Available Birds are the most important reservoirs of the influenza virus. Its maintenance in its natural hosts, including man, allows the influenza virus to reassorts its strains. The recent report of an avian influenza A (H5N1 virus in humans, was in a child with fatal respiratory illness in China, 1997. The current study was conducted to elucidate the transportation of the influenza by birds that migrate, annually, through the both Northern and Southern hemispheres, with special attention paid to the Vireo olivaceus [Juruviara(BR or Red-eyed vireo(USA] species, which travels from the USA to Brazil, and vice versa, and the Elaenia mesoleuca [Tuque(BR or (USA] species that flies over the entire Southern Hemisphere. There are two species of birds, which breed and migrate in São Paulo State, Brazil, and which were demonstrated to carry Influenza virus, were selected. The viral particles isolated were observed by electron microscopy. The influenza virus was detected by the House Duplex/PCR and Gloria molecular biology tests. The results demonstrated that the Elaenia mesoleuca and Vireo olivaceus bird species are carrying the Influenza virus whilst crossing both the Northern and Southern hemispheres. To understand the role that these migrating birds may play in epidemic influenza, in Brazil, characterization of avian influenza subtypes will be done.Os mais importantes reservatórios do vírus influenza são os pássaros. A manutenção do vírus influenza em hospedeiros naturais, inclusive o homem, permite que esse vírus realize rearranjos entre as suas cepas. O recente relato de uma cepa influenza aviária A(H5N1, em humanos, se deu em uma criança com doença respiratória fatal, na China em 1977. O presente estudo foi conduzido para elucidar o transporte da influenza por pássaros que migram, anualmente, através de ambos hemisférios o do Norte e do Sul, com especial atenção voltada à espécies Vireo olivaceo [Juruviara(BR e Red-eyed vireo(USA] que

  14. Anatomy and histochemistry of spread-wing posture in birds. 2. Gliding flight in the California gull, Larus californicus: a paradox of fast fibers and posture.

    Science.gov (United States)

    Meyers, R A; Mathias, E

    1997-09-01

    Gliding flight is a postural activity which requires the wings to be held in a horizontal position to support the weight of the body. Postural behaviors typically utilize isometric contractions in which no change in length takes place. Due to longer actin-myosin interactions, slow contracting muscle fibers represent an economical means for this type of contraction. In specialized soaring birds, such as vultures and pelicans, a deep layer of the pectoralis muscle, composed entirely of slow fibers, is believed to perform this function. Muscles involved in gliding posture were examined in California gulls (Larus californicus) and tested for the presence of slow fibers using myosin ATPase histochemistry and antibodies. Surprisingly small numbers of slow fibers were found in the M. extensor metacarpi radialis, M. coracobrachialis cranialis, and M. coracobrachialis caudalis, which function in wrist extension, wing protraction, and body support, respectively. The low number of slow fibers in these muscles and the absence of slow fibers in muscles associated with wing extension and primary body support suggest that gulls do not require slow fibers for their postural behaviors. Gulls also lack the deep belly to the pectoralis found in other gliding birds. Since bird muscle is highly oxidative, we hypothesize that fast muscle fibers may function to maintain wing position during gliding flight in California gulls.

  15. Projected changes in prevailing winds for transatlantic migratory birds under global warming.

    Science.gov (United States)

    La Sorte, Frank A; Fink, Daniel

    2017-03-01

    A number of terrestrial bird species that breed in North America cross the Atlantic Ocean during autumn migration when travelling to their non-breeding grounds in the Caribbean or South America. When conducting oceanic crossings, migratory birds tend to associate with mild or supportive winds, whose speed and direction may change under global warming. The implications of these changes for transoceanic migratory bird populations have not been addressed. We used occurrence information from eBird (1950-2015) to estimate the geographical location of population centres at a daily temporal resolution across the annual cycle for 10 transatlantic migratory bird species. We used this information to estimate the location and timing of autumn migration within the transatlantic flyway. We estimated how prevailing winds are projected to change within the transatlantic flyway during this time using daily wind speed anomalies (1996-2005 and 2091-2100) from 29 Atmosphere-Ocean General Circulation Models implemented under CMIP5. Autumn transatlantic migrants have the potential to encounter strong westerly crosswinds early in their transatlantic journey at intermediate and especially high migration altitudes, strong headwinds at low and intermediate migration altitudes within the Caribbean that increase in strength as the season progresses, and weak tailwinds at intermediate and high migration altitudes east of the Caribbean. The CMIP5 simulations suggest that, during this century, the likelihood of autumn transatlantic migrants encountering strong westerly crosswinds will diminish. As global warming progresses, the need for species to compensate or drift under the influence of strong westerly crosswinds during the initial phase of their autumn transatlantic journey may be diminished. Existing strategies that promote headwind avoidance and tailwind assistance will likely remain valid. Thus, climate change may reduce time and energy requirements and the chance of mortality or

  16. Differential toxic effects of Carbofuran and Diazinon on time of flight in pigeons (Columba livia): Potential for pesticide effects on migration

    International Nuclear Information System (INIS)

    Brasel, Jeffrey M.; Collier, Abby C.; Pritsos, Chris A.

    2007-01-01

    Cholinesterase inhibiting compounds such as carbamates and organophosphate insecticides have been widely used in agriculture since the ban on organochlorines in the 1970s. Carbofuran, a carbamate, and diazinon, an organophosphate, are among the most commonly implicated cholinesterase inhibitors in episodes of accidental avian toxicity and mortality. Despite the apparent effects of these compounds, little work has been done to study effects of low-level, environmentally relevant doses at the population level in migratory bird species. In this study, homing pigeons were used as surrogate species to assess the differences in the effect of incrementally low doses (0.0, 0.25, 0.5, and 1.0 mg/kg) of carbofuran and diazinon on time of flight and determine whether there was a threshold dose of either or both xenobiotics when orally administered at these levels. The results indicate that there is a significant dose-dependent increase in flight time in pigeons dosed with carbofuran while diazinon exposed pigeons showed little effect. More profound effects were noted with carbofuran with pigeons falling off the pace of the flock and a dose for highly significant increase in flight time elucidated between 0.5 and 1.0 mg/kg. The results of the studies validate the homing pigeon as a good subject for comparative studies of cholinesterase inhibitors in birds and the need for further research on repeated low-level exposures on populations of avian species

  17. Direct Evidence for Vision-based Control of Flight Speed in Budgerigars.

    Science.gov (United States)

    Schiffner, Ingo; Srinivasan, Mandyam V

    2015-06-05

    We have investigated whether, and, if so, how birds use vision to regulate the speed of their flight. Budgerigars, Melopsittacus undulatus, were filmed in 3-D using high-speed video cameras as they flew along a 25 m tunnel in which stationary or moving vertically oriented black and white stripes were projected on the side walls. We found that the birds increased their flight speed when the stripes were moved in the birds' flight direction, but decreased it only marginally when the stripes were moved in the opposite direction. The results provide the first direct evidence that Budgerigars use cues based on optic flow, to regulate their flight speed. However, unlike the situation in flying insects, it appears that the control of flight speed in Budgerigars is direction-specific. It does not rely solely on cues derived from optic flow, but may also be determined by energy constraints.

  18. Body fat influences departure from stopover sites in migratory birds: evidence from whole-island telemetry

    Science.gov (United States)

    Goymann, Wolfgang; Spina, Fernando; Ferri, Andrea; Fusani, Leonida

    2010-01-01

    Migration remains one of the great mysteries of animal life. Small migratory birds rely on refuelling stopovers after crossing ecological barriers such as deserts or seas. Previous studies have suggested that fuel reserves may determine stopover duration but this hypothesis could not be tested because of methodological limitations. Here, we provide evidence that subcutaneous fat stores determine stopover duration by measuring the permanence of migratory garden warblers (Sylvia borin) on a small Mediterranean island during spring migration with telemetry methods. Garden warblers with large amounts of fat stores departed the island significantly sooner than lean birds. All except one fat bird left the island on the same evening after capture, with a mean total stopover estimate of 8.8 hours. In contrast, the mean estimated total stopover duration of lean birds was 41.3 hours. To our knowledge, this is the first study that measures the true minimum stopover duration of a songbird during migration. PMID:20164077

  19. Aspects of population dynamics and feeding by piscivorous birds in ...

    African Journals Online (AJOL)

    Breaching events were associated with a change in feeding groups from waders to pursuit feeders, and a decrease in total bird numbers, most likely due to loss of potential littoral zone foraging habitat for waders resulting from reduced water levels. The highest bird numbers were recorded in winter reflecting the migration of ...

  20. Monitoring breeding and migration of neotropical migratory birds at Point Loma, San Diego County, California, 5-year summary, 2011–15

    Science.gov (United States)

    Lynn, Suellen; Madden, Melanie C.; Kus, Barbara E.

    2017-04-27

    Executive SummaryWe operated a bird banding station on the Point Loma peninsula in western San Diego County, California, during spring and summer from 2011 to 2015. The station was established in 2010 as part of a long-term monitoring program for neotropical migratory birds during spring migration and for breeding birds as part of the Monitoring Avian Productivity and Survivorship (MAPS) program.During spring migration (April and May), 2011–15, we captured 1,760 individual birds of 54 species, 91 percent (1,595) of which were newly banded, fewer than 1 percent (3) of which were recaptures that were banded in previous years, and 9 percent (143 hummingbirds, 2 hawks, and 17 other birds) of which we released unbanded. We observed an additional 22 species that were not captured. Thirty-four individuals were captured more than once. Bird capture rate averaged 0.49 ± 0.07 captures per net-hour (range 0.41–0.56). Species richness per day averaged 6.87 ± 0.33. Cardellina pusilla (Wilson’s warbler) was the most abundant spring migrant captured, followed by Empidonax difficilis (Pacific-slope flycatcher), Vireo gilvus (warbling vireo), Zonotrichia leucophrys (white-crowned sparrow), and Selasphorus rufus (rufous hummingbird). Captures of white-crowned sparrow decreased, and captures of Pacific-slope flycatcher increased, over the 5 years of our study. Fifty-six percent of known-sex individuals were male and 44 percent were female. The peak number of new species arriving per day ranged from April 1 (2013-six species) to April 16 (2012-five species). A significant correlation was determined between the number of migrants captured each day per net-hour and the density of echoes on the Next-Generation Radar (NEXRAD) images across all 5 years, and in each year except 2014. NEXRAD radar imagery appears to be a useful tool for detecting pulses in migration.Our results indicate that Point Loma provides stopover habitat during migration for 76 migratory species, including 20

  1. Flexible navigation response in common cuckoos Cuculus canorus displaced experimentally during migration

    DEFF Research Database (Denmark)

    Willemoes, Mikkel; Blas, Julio; Wikelski, Martin

    2015-01-01

    Migrating birds follow innate species-specific migration programs capable of guiding them along complex spatio-temporal routes, which may include several separate staging areas. Indeed, migration routes of common cuckoos Cuculus canorus show little variation between individuals; yet, satellite...... tracks of 11 experimentally displaced adults revealed an unexpected flexibility in individual navigation responses. The birds compensated for the translocation to unfamiliar areas by travelling toward population-specific staging areas, demonstrating true navigation capabilities. Individual responses...

  2. Migrate small, sound big: functional constraints on body size promote tracheal elongation in cranes.

    Science.gov (United States)

    Jones, M R; Witt, C C

    2014-06-01

    Organismal traits often represent the outcome of opposing selection pressures. Although social or sexual selection can cause the evolution of traits that constrain function or survival (e.g. ornamental feathers), it is unclear how the strength and direction of selection respond to ecological shifts that increase the severity of the constraint. For example, reduced body size might evolve by natural selection to enhance flight performance in migratory birds, but social or sexual selection favouring large body size may provide a countervailing force. Tracheal elongation is a potential outcome of these opposing pressures because it allows birds to convey an auditory signal of exaggerated body size. We predicted that the evolution of migration in cranes has coincided with a reduction in body size and a concomitant intensification of social or sexual selection for apparent large body size via tracheal elongation. We used a phylogenetic comparative approach to examine the relationships among migration distance, body mass and trachea length in cranes. As predicted, we found that migration distance correlated negatively with body size and positively with proportional trachea length. This result was consistent with our hypothesis that evolutionary reductions in body size led to intensified selection for trachea length. The most likely ultimate causes of intensified positive selection on trachea length are the direct benefits of conveying a large body size in intraspecific contests for mates and territories. We conclude that the strength of social or sexual selection on crane body size is linked to the degree of functional constraint. © 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

  3. Avian Information Systems: Developing Web-Based Bird Avoidance Models

    Directory of Open Access Journals (Sweden)

    Judy Shamoun-Baranes

    2008-12-01

    Full Text Available Collisions between aircraft and birds, so-called "bird strikes," can result in serious damage to aircraft and even in the loss of lives. Information about the distribution of birds in the air and on the ground can be used to reduce the risk of bird strikes and their impact on operations en route and in and around air fields. Although a wealth of bird distribution and density data is collected by numerous organizations, these data are not readily available nor interpretable by aviation. This paper presents two national efforts, one in the Netherlands and one in the United States, to develop bird avoidance nodels for aviation. These models integrate data and expert knowledge on bird distributions and migratory behavior to provide hazard maps in the form of GIS-enabled Web services. Both models are in operational use for flight planning and flight alteration and for airfield and airfield vicinity management. These models and their presentation on the Internet are examples of the type of service that would be very useful in other fields interested in species distribution and movement information, such as conservation, disease transmission and prevention, or assessment and mitigation of anthropogenic risks to nature. We expect that developments in cyber-technology, a transition toward an open source philosophy, and higher demand for accessible biological data will result in an increase in the number of biological information systems available on the Internet.

  4. Effects of flight speed upon muscle activity in hummingbirds.

    Science.gov (United States)

    Tobalske, Bret W; Biewener, Andrew A; Warrick, Douglas R; Hedrick, Tyson L; Powers, Donald R

    2010-07-15

    Hummingbirds have the smallest body size and highest wingbeat frequencies of all flying vertebrates, so they represent one endpoint for evaluating the effects of body size on sustained muscle function and flight performance. Other bird species vary neuromuscular recruitment and contractile behavior to accomplish flight over a wide range of speeds, typically exhibiting a U-shaped curve with maxima at the slowest and fastest flight speeds. To test whether the high wingbeat frequencies and aerodynamically active upstroke of hummingbirds lead to different patterns, we flew rufous hummingbirds (Selasphorus rufus, 3 g body mass, 42 Hz wingbeat frequency) in a variable-speed wind tunnel (0-10 m s(-1)). We measured neuromuscular activity in the pectoralis (PECT) and supracoracoideus (SUPRA) muscles using electromyography (EMG, N=4 birds), and we measured changes in PECT length using sonomicrometry (N=1). Differing markedly from the pattern in other birds, PECT deactivation occurred before the start of downstroke and the SUPRA was deactivated before the start of upstroke. The relative amplitude of EMG signal in the PECT and SUPRA varied according to a U-shaped curve with flight speed; additionally, the onset of SUPRA activity became relatively later in the wingbeat at intermediate flight speeds (4 and 6 m s(-1)). Variation in the relative amplitude of EMG was comparable with that observed in other birds but the timing of muscle activity was different. These data indicate the high wingbeat frequency of hummingbirds limits the time available for flight muscle relaxation before the next half stroke of a wingbeat. Unlike in a previous study that reported single-twitch EMG signals in the PECT of hovering hummingbirds, across all flight speeds we observed 2.9+/-0.8 spikes per contraction in the PECT and 3.8+/-0.8 spikes per contraction in the SUPRA. Muscle strain in the PECT was 10.8+/-0.5%, the lowest reported for a flying bird, and average strain rate was 7.4+/-0.2 muscle

  5. Interspecific comparison of the performance of soaring migrants in relation to morphology, meteorological conditions and migration strategies.

    Directory of Open Access Journals (Sweden)

    Ugo Mellone

    Full Text Available BACKGROUND: Performance of migrating birds can be affected by a number of intrinsic and extrinsic factors like morphology, meteorological conditions and migration strategies. We compared travel speeds of four raptor species during their crossing of the Sahara desert. Focusing the analyses on this region allows us to compare different species under equivalent conditions in order to disentangle which factors affect migratory performance. METHODOLOGY/PRINCIPAL FINDING: We tracked raptors using GPS satellite transmitters from Sweden, Spain and Italy, and evaluated their migratory performance at both an hourly and a daily scale. Hourly data (flight speed and altitude for intervals of two hours were analyzed in relation to time of day, species and season, and daily data (distance between roosting sites in relation to species, season, day length and tailwind support. CONCLUSIONS/SIGNIFICANCE: Despite a clear variation in morphology, interspecific differences were generally very small, and did only arise in spring, with long-distance migrants (>5000 km: osprey and Western marsh-harrier being faster than species that migrate shorter distances (Egyptian vulture and short-toed eagle. Our results suggest that the most important factor explaining hourly variation in flight speed is time of day, while at a daily scale, tailwind support is the most important factor explaining variation in daily distance, raising new questions about the consequences of possible future changes in worldwide wind patterns.

  6. Bird-marking in the Netherlands

    NARCIS (Netherlands)

    Oort, van E.D.

    1911-01-01

    Since May of this year the Museum of Natural History at Leyden is carrying into execution the inquiry into migration and other movements of birds in the Netherlands by means of aluminium rings. The results will be published in this periodical and at the same time in Dutch in the periodical of the

  7. Bird interactions with wind turbines : a Canadian case study

    Energy Technology Data Exchange (ETDEWEB)

    Brown, K.; Hamilton, B. [TAEM Ltd., Calgary, AB (Canada)

    2004-07-01

    An environmental study has been conducted on a wind farm adjacent to Castle River, in the foothills of the Rocky Mountains in Alberta. The objective was to determine the impact of the many wind turbines on birds. The study involved observations of different bird species including raptors, waterfowl and passerines. The observations looked at bird numbers, location relative to turbines, and changes in flight pattern. The study found that raptors flew around or over the turbine blades, while passerines remained below, and waterfowl flew up and over the blades. Very few dead birds were found over the monitoring period, suggesting that wind turbines do not have a major impact on birds. figs.

  8. An alternate and reversible method for flight restraint of cranes.

    Science.gov (United States)

    Zhang, Sen Lin; Yang, Shu Hui; Li, Bing; Xu, Yan Chun; Ma, Jian Hua; Xu, Jian Feng; Zhang, Xian Guang

    2011-01-01

    Flight restraint is important for zoos, safaris, and breeding centers for large birds. Currently used techniques for flight restraint include both surgical and non-surgical approaches. Surgical approaches usually cause permanent change to or removal of tendon, patagial membrane, or wing bones, and can cause pain and inflammation. Non-surgical approaches such as clipping or trimming feathers often alter the bird's appearance, and can damage growing blood feathers in fledglings or cause joint stiffness. We observed microstructure of primary feathers of the red-crowned crane (Grus japonensis) and found that the width of barbs is a determinative factor influencing vane stiffness and geometric parameters. We hypothesized that partial longitudinal excision of barbs on the ventral surface of the primary feathers would reduce the stiffness of the vane and render the feathers unable to support the crane's body weight during flight. Furthermore, we hypothesized that this modification of barbs would also change the aerodynamic performance of feathers such that they could not generate sufficient lift and thrust during flapping to enable the bird to fly. We tested this hypothesis on a red-crowned crane that had normal flight capability by excising the ventral margin of barbs on all 10 primaries on the left wing. The bird was unable to take off until the modified feathers were replaced by new ones. Removal of barbs proved to be a simple, non-invasive, low-cost and reversible method for flight restraint. It is potentially applicable to other large birds with similar structural characteristics of primary feathers. © 2010 Wiley-Liss, Inc.

  9. Approaching birds with drones: first experiments and ethical guidelines.

    Science.gov (United States)

    Vas, Elisabeth; Lescroël, Amélie; Duriez, Olivier; Boguszewski, Guillaume; Grémillet, David

    2015-02-01

    Unmanned aerial vehicles, commonly called drones, are being increasingly used in ecological research, in particular to approach sensitive wildlife in inaccessible areas. Impact studies leading to recommendations for best practices are urgently needed. We tested the impact of drone colour, speed and flight angle on the behavioural responses of mallards Anas platyrhynchos in a semi-captive situation, and of wild flamingos (Phoenicopterus roseus) and common greenshanks (Tringa nebularia) in a wetland area. We performed 204 approach flights with a quadricopter drone, and during 80% of those we could approach unaffected birds to within 4 m. Approach speed, drone colour and repeated flights had no measurable impact on bird behaviour, yet they reacted more to drones approaching vertically. We recommend launching drones farther than 100 m from the birds and adjusting approach distance according to species. Our study is a first step towards a sound use of drones for wildlife research. Further studies should assess the impacts of different drones on other taxa, and monitor physiological indicators of stress in animals exposed to drones according to group sizes and reproductive status. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  10. Epidemic spread in coupled populations with seasonally varying migration rates

    Science.gov (United States)

    Muzyczyn, Adam; Shaw, Leah B.

    2009-03-01

    The H5N1 strain of avian influenza has spread worldwide, and this spread may be due to seasonal migration of birds and mixing of birds from different regions in the wintering grounds. We studied a multipatch model for avian influenza with seasonally varying migration rates. The bird population was divided into two spatially distinct patches, or subpopulations. Within each patch, the disease followed the SIR (susceptible-infected-recovered) model for epidemic spread. Migration rates were varied periodically, with a net flux toward the breeding grounds during the spring and towards the wintering grounds during the fall. The case of two symmetric patches reduced to single-patch SIR dynamics. However, asymmetry in the birth and contact rates in the breeding grounds and wintering grounds led to bifurcations to longer period orbits and chaotic dynamics. We studied the bifurcation structure of the model and the phase relationships between outbreaks in the two patches.

  11. The potential role of migratory birds in the transmission of zoonoses

    Directory of Open Access Journals (Sweden)

    Vasilios Tsiouris

    2008-12-01

    Full Text Available The instinct for survival leads migratory birds to exploit seasonal opportunities for breeding habitats and food supplies. Consequently, they travel across national and international borders. These birds are distinguished in local migrants, short-distance, long-distance and vagrant and nomadic migrants. They can transfer micro-organisms across the globe and play a significant role in the ecology and circulation of pathogenic organisms. They are implicated in the transmission of zoonoses as biological and mechanical carriers and as hosts and carriers of infected ectoparasites. They can cause water-borne, tick-borne and insect-borne diseases. Favourable agents, such as seasonality and stress due to migration, influence the transmission of pathogens. The migration of birds is a natural phenomenon that is followed by the unavoidable repercussions of the participation of these birds as carriers or hosts in the transmission of pathogens. It is not possible to interrupt this sequence but risks can be minimised by controlling and preventing perilous situations. Surveillance of wetlands, ‘stopovers’, places of destination and wintering regions can be done. Furthermore, the implementation strict biosecurity measures that reduce contact with migratory birds will limit the transmission of pathogens.

  12. Bird Conservation Implementation and Integration in the Americas: Proceedings of the Third International Partners in Flight Conference. 2002 March 20-24; Asilomar, California, Volume 1 and 2

    Science.gov (United States)

    C. John Ralph; Terrell D. Rich

    2005-01-01

    These two volumes contain in part papers presented at the Third International Partners in Flight Conference: A Workshop on Bird Conservation Implementation and Integration, which was held 20-24 March 2002 at the Asilomar Conference Center in Monterey, California. The conference gathered together researchers, educators, foresters, monitoring specialists, planners, and...

  13. Pigeons (C. livia Follow Their Head during Turning Flight: Head Stabilization Underlies the Visual Control of Flight

    Directory of Open Access Journals (Sweden)

    Ivo G. Ros

    2017-12-01

    Full Text Available Similar flight control principles operate across insect and vertebrate fliers. These principles indicate that robust solutions have evolved to meet complex behavioral challenges. Following from studies of visual and cervical feedback control of flight in insects, we investigate the role of head stabilization in providing feedback cues for controlling turning flight in pigeons. Based on previous observations that the eyes of pigeons remain at relatively fixed orientations within the head during flight, we test potential sensory control inputs derived from head and body movements during 90° aerial turns. We observe that periods of angular head stabilization alternate with rapid head repositioning movements (head saccades, and confirm that control of head motion is decoupled from aerodynamic and inertial forces acting on the bird's continuously rotating body during turning flapping flight. Visual cues inferred from head saccades correlate with changes in flight trajectory; whereas the magnitude of neck bending predicts angular changes in body position. The control of head motion to stabilize a pigeon's gaze may therefore facilitate extraction of important motion cues, in addition to offering mechanisms for controlling body and wing movements. Strong similarities between the sensory flight control of birds and insects may also inspire novel designs of robust controllers for human-engineered autonomous aerial vehicles.

  14. Estimating the surface area of birds: using the homing pigeon (Columba livia as a model

    Directory of Open Access Journals (Sweden)

    Cristina R. Perez

    2014-05-01

    Full Text Available Estimation of the surface area of the avian body is valuable for thermoregulation and metabolism studies as well as for assessing exposure to oil and other surface-active organic pollutants from a spill. The use of frozen carcasses for surface area estimations prevents the ability to modify the posture of the bird. The surface area of six live homing pigeons in the fully extended flight position was estimated using a noninvasive method. An equation was derived to estimate the total surface area of a pigeon based on its body weight. A pigeon's surface area in the fully extended flight position is approximately 4 times larger than the surface area of a pigeon in the perching position. The surface area of a bird is dependent on its physical position, and, therefore, the fully extended flight position exhibits the maximum area of a bird and should be considered the true surface area of a bird.

  15. Estimating the surface area of birds: using the homing pigeon (Columba livia) as a model.

    Science.gov (United States)

    Perez, Cristina R; Moye, John K; Pritsos, Chris A

    2014-05-08

    Estimation of the surface area of the avian body is valuable for thermoregulation and metabolism studies as well as for assessing exposure to oil and other surface-active organic pollutants from a spill. The use of frozen carcasses for surface area estimations prevents the ability to modify the posture of the bird. The surface area of six live homing pigeons in the fully extended flight position was estimated using a noninvasive method. An equation was derived to estimate the total surface area of a pigeon based on its body weight. A pigeon's surface area in the fully extended flight position is approximately 4 times larger than the surface area of a pigeon in the perching position. The surface area of a bird is dependent on its physical position, and, therefore, the fully extended flight position exhibits the maximum area of a bird and should be considered the true surface area of a bird. © 2014. Published by The Company of Biologists Ltd | Biology Open.

  16. Functional morphometric analysis of the furcula in mesozoic birds.

    Directory of Open Access Journals (Sweden)

    Roger A Close

    Full Text Available The furcula displays enormous morphological and structural diversity. Acting as an important origin for flight muscles involved in the downstroke, the form of this element has been shown to vary with flight mode. This study seeks to clarify the strength of this form-function relationship through the use of eigenshape morphometric analysis coupled with recently developed phylogenetic comparative methods (PCMs, including phylogenetic Flexible Discriminant Analysis (pFDA. Additionally, the morphospace derived from the furculae of extant birds is used to shed light on possible flight adaptations of Mesozoic fossil taxa. While broad conclusions of earlier work are supported (U-shaped furculae are associated with soaring, strong anteroposterior curvature with wing-propelled diving, correlations between form and function do not appear to be so clear-cut, likely due to the significantly larger dataset and wider spectrum of flight modes sampled here. Interclavicular angle is an even more powerful discriminator of flight mode than curvature, and is positively correlated with body size. With the exception of the close relatives of modern birds, the ornithuromorphs, Mesozoic taxa tend to occupy unique regions of morphospace, and thus may have either evolved unfamiliar flight styles or have arrived at similar styles through divergent musculoskeletal configurations.

  17. Session: Avian migration and implications for wind power development in the Eastern United States

    Energy Technology Data Exchange (ETDEWEB)

    Mabey, Sarah; Cooper, Brian

    2004-09-01

    This session at the Wind Energy and Birds/Bats workshop consisted of two presentations followed by a discussion/question and answer period. The session was arranged to convey what is known about avian migration, particularly in the eastern US. The first presentation ''Migration Ecology: Issues of Scale and Behavior'' by Sarah Mabey frames the issue of migratory bird interactions with wind energy facilities from an ecological perspective: when, where, and why are migrant bird species vulnerable to wind turbine collision. The second presentation ''Radar Studies of Nocturnal Migration at Wind Sites in the Eastern US'' by Brian Cooper reported on radar studies conducted at wind sites in the eastern US, including Mount Storm, Clipper Wind, and others.

  18. Exploiting Science: Enhancing the Safety Training of Pilots to Reduce the Risk of Bird Strikes

    Science.gov (United States)

    Mendonca, Flavio A. C.

    Analysis of bird strikes to aviation in the U.S. from 1990 to 2015 indicate that the successful mitigation efforts at airports, which must be sustained, have reduced incidents with damage and a negative effect-on-flight since 2000. However, such efforts have done little to reduce strikes outside the airport jurisdiction, such as occurred with US Airways Flight 1549 in 2009. There are basically three strategies to mitigate the risk of bird strikes: standards set by aviation authorities, technology, and actions by crewmembers. Pilots play an important role as stakeholders in the prevention of bird strikes, especially outside the airport environment. Thus, safety efforts require enhanced risk management and aeronautical decision-making training for flight crews. The purpose of this study was to determine if a safety training protocol could effectively enhance CFR Part 141 general aviation pilots' knowledge and skills to reduce the risk of bird strikes to aviation. Participants were recruited from the Purdue University professional flight program and from Purdue Aviation. The researcher of this study used a pretest posttest experimental design. Additionally, qualitative data were collected through open-ended questions in the pretest, posttest, and a follow-up survey questionnaire. The participants' pretest and posttest scores were analyzed using parametric and nonparametric tests. Results indicated a significant increase in the posttest scores of the experimental group. An investigation of qualitative data showed that the topic "safety management of bird hazards by pilots" is barely covered during the ground and flight training of pilots. Furthermore, qualitative data suggest a misperception of the safety culture tenets and a poor familiarity with the safety risk management process regarding bird hazards. Finally, the researcher presented recommendations for practice and future research.

  19. Current selection for lower migratory activity will drive the evolution of residency in a migratory bird population.

    Science.gov (United States)

    Pulido, Francisco; Berthold, Peter

    2010-04-20

    Global warming is impacting biodiversity by altering the distribution, abundance, and phenology of a wide range of animal and plant species. One of the best documented responses to recent climate change is alterations in the migratory behavior of birds, but the mechanisms underlying these phenotypic adjustments are largely unknown. This knowledge is still crucial to predict whether populations of migratory birds will adapt to a rapid increase in temperature. We monitored migratory behavior in a population of blackcaps (Sylvia atricapilla) to test for evolutionary responses to recent climate change. Using a common garden experiment in time and captive breeding we demonstrated a genetic reduction in migratory activity and evolutionary change in phenotypic plasticity of migration onset. An artificial selection experiment further revealed that residency will rapidly evolve in completely migratory bird populations if selection for shorter migration distance persists. Our findings suggest that current alterations of the environment are favoring birds wintering closer to the breeding grounds and that populations of migratory birds have strongly responded to these changes in selection. The reduction of migratory activity is probably an important evolutionary process in the adaptation of migratory birds to climate change, because it reduces migration costs and facilitates the rapid adjustment to the shifts in the timing of food availability during reproduction.

  20. Impact of Environmental Changes on Migratory Bird Survival

    Directory of Open Access Journals (Sweden)

    Sabine Stöcker-Segre

    2014-01-01

    Full Text Available We present a mathematical model that studies and simulates the interconnection between energetic and ecological aspects of bird migration. By comparing model predictions with experimental data, we show that it can be used to assess the impact of changing environmental conditions in breeding, wintering, and stop-over sites on migratory success. We relate in particular to the European white stork (Ciconia ciconia and its Eastern migration route and discuss questions concerning the timing, stopover, and feeding behavior en route. Opinions concerning the importance of resource availability and resource quality en route are divided. Whereas some studies have shown that storks gain weight in the wintering site, but almost do not feed en route, others stress the importance of the quality of stop-over locations. We address these questions and simulate the development of stork populations for changing environmental conditions. We demonstrate that resource availability and competition for breeding sites are crucial factors determining the timing of spring migration and the length of stop-over periods. Analyzing the robustness of migration strategies with respect to changing environmental conditions, we show that birds will shorten their stay in stop-over places of poor resource availability rather than prolonging it in the attempt to gain time for accumulating fat reserves.

  1. Conservation Priorities for Terrestrial Birds in the Northeastern United States

    Science.gov (United States)

    Kenneth V. Rosenberg; Jeffrey V. Wells

    2005-01-01

    As part of the Partners in Flight (PIF) bird-conservation planning process, we assessed breeding land bird species according to seven categories of population vulnerability to derive a priority species pool in each of 12 physiographic areas that overlap the northeastern U.S. We then grouped species into the following habitat-species suites: (1) boreal-mountaintop...

  2. Changes in timing, duration, and symmetry of molt of Hawaiian forest birds.

    Science.gov (United States)

    Freed, Leonard A; Cann, Rebecca L

    2012-01-01

    Food limitation greatly affects bird breeding performance, but the effect of nutritive stress on molt has barely been investigated outside of laboratory settings. Here we show changes in molting patterns for an entire native Hawaiian bird community at 1650-1900 m elevation on the Island of Hawaii between 1989-1999 and 2000-2006, associated with severe food limitation throughout the year beginning in 2000. Young birds and adults of all species took longer to complete their molt, including months never or rarely used during the 1989-1999 decade. These included the cold winter months and even the early months of the following breeding season. In addition, more adults of most species initiated their molt one to two months earlier, during the breeding season. Suspended molt, indicated by birds temporarily not molting primary flight feathers during the months of peak primary molt, increased in prevalence. Food limitation reached the point where individuals of all species had asymmetric molt, with different primary flight feathers molted on each wing. These multiple changes in molt, unprecedented in birds, had survival consequences. Adult birds captured during January to March, 2000-2004, had lower survival in four of five species with little effect of extended molt. Extended molt may be adaptive for a nutrient stressed bird to survive warm temperatures but not cool winter temperatures that may obliterate the energy savings. The changing molt of Hawaiian birds has many implications for conservation and for understanding life history aspects of molt of tropical birds.

  3. USDA Forest Service goals and programs for monitoring neotropical migratory birds

    Science.gov (United States)

    Patricia Manley

    1993-01-01

    The USDA Forest Service (USFS) developed goals, objectives, and guidelines for monitoring neotropical migratory birds (NTMB) on National Forest System lands in response to the Neotropical Migratory Bird Conservation Program Partners in Flight. A USFS task group developed a hierarchical monitoring framework designed to define priorities for type of monitoring data....

  4. Co-fluctuation among bird species in their migration timing

    Czech Academy of Sciences Publication Activity Database

    Hubálek, Zdeněk

    2005-01-01

    Roč. 54, 1-2 (2005), s. 159-164 ISSN 0139-7893 Institutional research plan: CEZ:AV0Z60930519 Keywords : migratory birds * phenology * spring arrival Subject RIV: EG - Zoology Impact factor: 0.585, year: 2005 http://www.ivb.cz/folia/54/1-2/159-164.pdf

  5. Long-Term Phenological Shifts in Raptor Migration and Climate

    Science.gov (United States)

    Jaffré, Mikaël; Beaugrand, Grégory; Goberville, Éric; Jiguet, Frédéric; Kjellén, Nils; Troost, Gerard; Dubois, Philippe J.; Leprêtre, Alain; Luczak, Christophe

    2013-01-01

    Climate change is having a discernible effect on many biological and ecological processes. Among observed changes, modifications in bird phenology have been widely documented. However, most studies have interpreted phenological shifts as gradual biological adjustments in response to the alteration of the thermal regime. Here we analysed a long-term dataset (1980-2010) of short-distance migratory raptors in five European regions. We revealed that the responses of these birds to climate-induced changes in autumn temperatures are abrupt and synchronous at a continental scale. We found that when the temperatures increased, birds delayed their mean passage date of autumn migration. Such delay, in addition to an earlier spring migration, suggests that a significant warming may induce an extension of the breeding-area residence time of migratory raptors, which may eventually lead to residency. PMID:24223888

  6. Long-term phenological shifts in raptor migration and climate.

    Directory of Open Access Journals (Sweden)

    Mikaël Jaffré

    Full Text Available Climate change is having a discernible effect on many biological and ecological processes. Among observed changes, modifications in bird phenology have been widely documented. However, most studies have interpreted phenological shifts as gradual biological adjustments in response to the alteration of the thermal regime. Here we analysed a long-term dataset (1980-2010 of short-distance migratory raptors in five European regions. We revealed that the responses of these birds to climate-induced changes in autumn temperatures are abrupt and synchronous at a continental scale. We found that when the temperatures increased, birds delayed their mean passage date of autumn migration. Such delay, in addition to an earlier spring migration, suggests that a significant warming may induce an extension of the breeding-area residence time of migratory raptors, which may eventually lead to residency.

  7. The Far East taiga forest: unrecognized inhospitable terrain for migrating Arctic-nesting waterbirds?

    Directory of Open Access Journals (Sweden)

    Xin Wang

    2018-02-01

    Full Text Available The degree of inhospitable terrain encountered by migrating birds can dramatically affect migration strategies and their evolution as well as influence the way we develop our contemporary flyway conservation responses to protect them. We used telemetry data from 44 tagged individuals of four large-bodied, Arctic breeding waterbird species (two geese, a swan and one crane species to show for the first time that these birds fly non-stop over the Far East taiga forest, despite their differing ecologies and migration routes. This implies a lack of suitable taiga refuelling habitats for these long-distance migrants. These results underline the extreme importance of northeast China spring staging habitats and of Arctic areas prior to departure in autumn to enable birds to clear this inhospitable biome, confirming the need for adequate site safeguard to protect these populations throughout their annual cycle.

  8. WT-BIRD. Bird collision monitoring system for multi-megawatt wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Wiggelinkhuizen, E.J.; Rademakers, L.W.M.M.; Barhorst, S.A.M. [ECN Wind Energy, Petten (Netherlands); Den Boon, H.J. [E-Connection Project, Bunnik (Netherlands); Dirksen, S. [Bureau Waardenburg, Culemborg (Netherlands)

    2007-05-15

    A new method for detection and registration of bird collisions has been developed that is suitable for continuous remote operation in both onshore and offshore wind farms. The characteristic sound of a collision is detected by sensors in the blades, which triggers the storage of video registrations and sends an alert message to the operator. A prototype has been tested successfully on a Nordex N80/2.5MW turbine at ECN's Wind turbine Test park Wieringermeer. Compared to other methods employed so far this monitoring system will reduce the uncertainty in the number of birds killed by collisions with wind turbines. Further, the system enables the operator to identify species and to study the collision mechanisms. It has been found that this system can also be used for monitoring of other events in order to save costs for inspection and repair after incidents. For offshore wind farms, the WT-Bird system is currently the only alternative to count the number of bird collisions. Functional tests with tennis balls that were shot against rotating blades showed that the majority of the impacts were detected. The flight track of these dummies and the collision events were clearly visible on the video registrations. During the monitoring period of about one year two bird collisions were detected. The video recordings confirmed that a collision took place and showed that the location of both collisions was near the blade root, which resulted that in both cases the bird was not (immediately) killed. Therefore no corpses could be found beneath the turbine after these events. Also during the rest of the monitoring period no corpses were found beneath the turbine.

  9. Tracking from the tropics reveals behaviour of juvenile songbirds on their first spring migration.

    Directory of Open Access Journals (Sweden)

    Emily A McKinnon

    Full Text Available Juvenile songbirds on spring migration travel from tropical wintering sites to temperate breeding destinations thousands of kilometres away with no prior experience to guide them. We provide a first glimpse at the migration timing, routes, and stopover behaviour of juvenile wood thrushes (Hylocichla mustelina on their inaugural spring migration by using miniaturized archival geolocators to track them from Central America to the U.S. and Canada. We found significant differences between the timing of juvenile migration and that of more experienced adults: juveniles not only departed later from tropical wintering sites relative to adults, they also became progressively later as they moved northward. The increasing delay was driven by more frequent short stops by juveniles along their migration route, particularly in the U.S. as they got closer to breeding sites. Surprisingly, juveniles were just as likely as adults to cross the Gulf of Mexico, an open-water crossing of 800-1000 km, and migration route at the Gulf was not significantly different for juveniles relative to adults. To determine if the later departure of juveniles was related to poor body condition in winter relative to adults, we examined percent lean body mass, fat scores, and pectoral muscle scores of juvenile versus adult birds at a wintering site in Belize. We found no age-related differences in body condition. Later migration timing of juveniles relative to adults could be an adaptive strategy (as opposed to condition-dependent to avoid the high costs of fast migration and competition for breeding territories with experienced and larger adults. We did find significant differences in wing size between adults and juveniles, which could contribute to lower flight efficiency of juveniles and thus slower overall migration speed. We provide the first step toward understanding the "black box" of juvenile songbird migration by documenting their migration timing and en route performance.

  10. On Wings of the Minimum Induced Drag: Spanload Implications for Aircraft and Birds

    Science.gov (United States)

    Bowers, Albion H.; Murillo, Oscar J.; Jensen, Robert (Red); Eslinger, Brian; Gelzer, Christian

    2016-01-01

    For nearly a century Ludwig Prandtl's lifting-line theory remains a standard tool for understanding and analyzing aircraft wings. The tool, said Prandtl, initially points to the elliptical spanload as the most efficient wing choice, and it, too, has become the standard in aviation. Having no other model, avian researchers have used the elliptical spanload virtually since its introduction. Yet over the last half-century, research in bird flight has generated increasing data incongruous with the elliptical spanload. In 1933 Prandtl published a little-known paper presenting a superior spanload: any other solution produces greater drag. We argue that this second spanload is the correct model for bird flight data. Based on research we present a unifying theory for superior efficiency and coordinated control in a single solution. Specifically, Prandtl's second spanload offers the only solution to three aspects of bird flight: how birds are able to turn and maneuver without a vertical tail; why birds fly in formation with their wingtips overlapped; and why narrow wingtips do not result in wingtip stall. We performed research using two experimental aircraft designed in accordance with the fundamentals of Prandtl's second paper, but applying recent developments, to validate the various potentials of the new spanload, to wit: as an alternative for avian researchers, to demonstrate the concept of proverse yaw, and to offer a new method of aircraft control and efficiency.

  11. Visual and radar observations of birds in relation to collision risk at the Horns Rev offshore wind farm. Annual status report 2003

    Energy Technology Data Exchange (ETDEWEB)

    Kjaer Christensen, T.; Hounisen, J.P.; Clausager, I.; Krag Petersen, I.

    2004-07-01

    The aim of the project is to assess the collision risk between birds and wind turbines at the Horns Rev wind farm. In 2003 the studies focused on describing bird movements in relation to the wind farm and to identify the species-specific behavioural responses towards the wind turbines shown by migrating and staging species. The Horns Rev area lies in a region known to be important for substantial water bird migration as well as holding internationally important numbers of several wintering and staging water bird species. (au)

  12. One year of migration data for a western yellow-billed cuckoo

    Science.gov (United States)

    Sechrist, Juddson D.; Paxton, Eben H.; Ahlers, Darrell D.; Doster, Robert H.; Ryan, Vicky M.

    2012-01-01

    In 2009, we studied the migration of the Western Yellow-billed Cuckoo by capturing 13 breeding birds on the middle Rio Grande, New Mexico, and attaching a 1.5-g Mk 14-S British Antarctic Survey geolocator to each bird. In 2010, we recaptured one of the cuckoos, enabling us to download its geolocation data. The cuckoo had flown approximately 9500 km during its southward migration, traveling through Central America to winter in portions of Bolivia, Brazil, Paraguay, and Argentina. The spring migration route differed somewhat from the fall route, with the cuckoo bypassing Central America to migrate through the Caribbean. Additionally, it moved between New Mexico and Mexico at the end of summer in 2009 and again in 2010 before being recaptured at its breeding site. Our results, albeit from one individual, hint at a dynamic migration strategy and have broad implications for the ecology and conservation of the Western Yellow-billed Cuckoo, a species of conservation concern.

  13. A new conservation partnership: conserving the migratory birds of the Americas

    Science.gov (United States)

    Jack C. Capp; David Mehlman

    Over five billion birds move each year across the Americas, flying great distances over almost every location and habitat on the continents (Weidensaul 1999). Over 350 of the over 800 bird species in the United States migrate each year to Latin America and the Caribbean (Degraaf and Rappole 1995). Some fly each way over 4000 miles, chasing the seasons across oceans and...

  14. Avian migrants adjust migration in response to environmental conditions en route

    DEFF Research Database (Denmark)

    Tøttrup, Anders P; Thorup, Kasper; Rainio, Kalle

    2008-01-01

    The onset of migration in birds is assumed to be primarily under endogenous control in long-distance migrants. Recently, climate changes appear to have been driving a rapid change in breeding area arrival. However, little is known about the climatic factors affecting migratory birds during...... covering the entire migration period every year from observatories located in the Middle East and northern Europe, we show that passage of the Sahara Desert is delayed and correlated with improved conditions in the wintering areas. By contrast, migrants travel more rapidly through Europe, and adjust...... the migration cycle, or whether recently reported phenological changes are caused by plastic behavioural responses or evolutionary change. Here, we investigate how environmental conditions in the wintering areas as well as en route towards breeding areas affect timing of migration. Using data from 1984 to 2004...

  15. Bird-strike of a Cinereous Vulture Aegypius monachus in the ...

    African Journals Online (AJOL)

    Campbell Murn

    Bird-strike of a Cinereous Vulture Aegypius monachus in the Balearic Islands, Spain. Alvaro Camiña1* and Joan ... http://dx.doi.org/10.4314/vulnew.v71i1.3. On 15 September 2016 a Lufthansa flight en route from Munich ... nautical miles from runway 24L. Considering the altitude of the area of around 100 meters, the bird ...

  16. Geography of spring landbird migration through riparian habitats in southwestern North America

    Science.gov (United States)

    Susan K. Skagen; Jeffrey F. Kelly; Charles van Riper III; Richard L. Hutto; Deborah M. Finch; David J. Krueper; Cynthia P. Melcher

    2005-01-01

    Migration stopover resources, particularly riparian habitats, are critically important to landbirds migrating across the arid southwestern region of North America. To explore the effects of species biogeography and habitat affinity on spring migration patterns, we synthesized existing bird abundance and capture data collected in riparian habitats of the borderlands...

  17. A basal dromaeosaurid and size evolution preceding avian flight.

    Science.gov (United States)

    Turner, Alan H; Pol, Diego; Clarke, Julia A; Erickson, Gregory M; Norell, Mark A

    2007-09-07

    Fossil evidence for changes in dinosaurs near the lineage leading to birds and the origin of flight has been sparse. A dinosaur from Mongolia represents the basal divergence within Dromaeosauridae. The taxon's small body size and phylogenetic position imply that extreme miniaturization was ancestral for Paraves (the clade including Avialae, Troodontidae, and Dromaeosauridae), phylogenetically earlier than where flight evolution is strongly inferred. In contrast to the sustained small body sizes among avialans throughout the Cretaceous Period, the two dinosaurian lineages most closely related to birds, dromaeosaurids and troodontids, underwent four independent events of gigantism, and in some lineages size increased by nearly three orders of magnitude. Thus, change in theropod body size leading to flight's origin was not unidirectional.

  18. Timing of pre-nuptial migration and leap-frog patterns in Yellow ...

    African Journals Online (AJOL)

    nuptial migration period, in parts of the wintering grounds most distant from the breeding area. Birds breeding at the highest latitudes are the latest to depart on prenuptial migration, and so can take advantage of this surge by extending their ...

  19. Monitoring potential geographical distribution of four wild bird species in China

    Science.gov (United States)

    Dai, S.; Feng, D.; Xu, B.

    2015-12-01

    The outbreak of highly pathogenic avian influenza (HPAI) of the H5N1 subtype in wild birds and poultry have caught worldwide attention. To explore the association between wild bird migration and avian influenza virus transmission, we monitored potential geographical distribution of four wild bird species that might carry the avian influenza viruses in China. They are Bar-headed geese (Anser indicus), Ruddy Shelduck (Tadorna ferruginea), Whooper Swan (Cygnus cygnus) and Black-headed Gull (Larus ridibundus). They served as major reservoir of the avian influenza viruses. We used bird watching records with the precise latitude/longitude coordinates from January 2002 to August 2014, and environmental variables with a pixel resolution of 5 km × 5 km from 2002 to 2014. The study utilized maximum entropy (MaxEnt) model based on ecological niche model approaches, and got the following results: 1) MaxEnt model have good discriminatory ability with the area under the curve (AUC) of the receiver operating curve (ROC) of 0.86-0.97; 2) The four wild bird species were estimated to concentrate in the North China Plain, the middle and lower region of the Yangtze River, Qinghai Lake, Tianshan Mountain and Tarim Basin, part of Tibet Plateau, and Hengduan Mountains; 3) Radiation and the minimum temperature were found to provide the most significant information. Our findings will help to understand the spread of avian influenza viruses by wild bird migration in China, which benefits for effective monitoring strategies and prevention measures.

  20. Changes in timing, duration, and symmetry of molt of Hawaiian forest birds.

    Directory of Open Access Journals (Sweden)

    Leonard A Freed

    Full Text Available Food limitation greatly affects bird breeding performance, but the effect of nutritive stress on molt has barely been investigated outside of laboratory settings. Here we show changes in molting patterns for an entire native Hawaiian bird community at 1650-1900 m elevation on the Island of Hawaii between 1989-1999 and 2000-2006, associated with severe food limitation throughout the year beginning in 2000. Young birds and adults of all species took longer to complete their molt, including months never or rarely used during the 1989-1999 decade. These included the cold winter months and even the early months of the following breeding season. In addition, more adults of most species initiated their molt one to two months earlier, during the breeding season. Suspended molt, indicated by birds temporarily not molting primary flight feathers during the months of peak primary molt, increased in prevalence. Food limitation reached the point where individuals of all species had asymmetric molt, with different primary flight feathers molted on each wing. These multiple changes in molt, unprecedented in birds, had survival consequences. Adult birds captured during January to March, 2000-2004, had lower survival in four of five species with little effect of extended molt. Extended molt may be adaptive for a nutrient stressed bird to survive warm temperatures but not cool winter temperatures that may obliterate the energy savings. The changing molt of Hawaiian birds has many implications for conservation and for understanding life history aspects of molt of tropical birds.

  1. Changes in Timing, Duration, and Symmetry of Molt of Hawaiian Forest Birds

    Science.gov (United States)

    Freed, Leonard A.; Cann, Rebecca L.

    2012-01-01

    Food limitation greatly affects bird breeding performance, but the effect of nutritive stress on molt has barely been investigated outside of laboratory settings. Here we show changes in molting patterns for an entire native Hawaiian bird community at 1650–1900 m elevation on the Island of Hawaii between 1989–1999 and 2000–2006, associated with severe food limitation throughout the year beginning in 2000. Young birds and adults of all species took longer to complete their molt, including months never or rarely used during the 1989–1999 decade. These included the cold winter months and even the early months of the following breeding season. In addition, more adults of most species initiated their molt one to two months earlier, during the breeding season. Suspended molt, indicated by birds temporarily not molting primary flight feathers during the months of peak primary molt, increased in prevalence. Food limitation reached the point where individuals of all species had asymmetric molt, with different primary flight feathers molted on each wing. These multiple changes in molt, unprecedented in birds, had survival consequences. Adult birds captured during January to March, 2000–2004, had lower survival in four of five species with little effect of extended molt. Extended molt may be adaptive for a nutrient stressed bird to survive warm temperatures but not cool winter temperatures that may obliterate the energy savings. The changing molt of Hawaiian birds has many implications for conservation and for understanding life history aspects of molt of tropical birds. PMID:22279547

  2. Number of Migration Scenarios Passing through each HUC

    Data.gov (United States)

    U.S. Environmental Protection Agency — Forest dwelling neotropical migratory birds require intact forested stopovers during migration. The number of paths that pass through a HUC highlight that huc's...

  3. Application of models to conservation planning for terrestrial birds in North America

    Science.gov (United States)

    Fitzgerald, Jane A.; Thogmartin, Wayne E.; Dettmers, Randy; Jones, Tim; Rustay, Christopher; Ruth, Janet M.; Thompson, Frank R.; Will, Tom; Millspaugh, Joshua J.; Thompson, Frank R.

    2009-01-01

    Partners in Flight (PIF), a public–private coalition for the conservation of land birds, has developed one of four international bird conservation plans recognized under the auspices of the North American Bird Conservation Initiative (NABCI). Partners in Flight prioritized species most in need of conservation attention and set range-wide population goals for 448 species of terrestrial birds. Partnerships are now tasked with developing spatially explicit estimates of the distribution, and abundance of priority species across large ecoregions and identifying habitat acreages needed to support populations at prescribed levels. The PIF Five Elements process of conservation design identifies five steps needed to implement all bird conservation at the ecoregional scale. Habitat assessment and landscape characterization describe the current amounts of different habitat types and summarize patch characteristics, and landscape configurations that define the ability of a landscape to sustain healthy bird populations and are a valuable first step to describing the planning area before pursuing more complex species-specific models. Spatially linked database models, landscape-scale habitat suitability models, and statistical models are viable alternatives for predicting habitat suitability or bird abundance across large planning areas to help assess conservation opportunities, design landscapes to meet population objectives, and monitor change in habitat suitability or bird numbers over time.Bird conservation in the United States is a good example of the use of models in large-scale wildlife conservation planning because of its geographic extent, focus on multiple species, involvement of multiple partners, and use of simple to complex models. We provide some background on the recent development of bird conservation initiatives in the United States and the approaches used for regional conservation assessment and planning. We focus on approaches being used for landscape

  4. Differential timing and latitudinal variation in sex ratio of Aquatic Warblers during the autumn migration

    Science.gov (United States)

    Wojczulanis-Jakubas, Katarzyna; Chrostek, Małgorzata E.; Jiguet, Frédéric; Martínez, Carlos Zumalacárregui; Miguélez, David; Neto, Júlio M.

    2017-12-01

    Differential migration has been extensively reported in spring, but less so in autumn, particularly in relation to sex in monomorphic bird species. Here, we analysed the autumn passage of a monomorphic, globally threatened passerine, the Aquatic Warbler Acrocephalus paludicola throughout Western Europe, with regard to age and sex. We showed that, overall, adults migrated earlier than first-year birds, and males migrated earlier than females during the autumn migration. This may be caused by an overall social dominance of adults over immatures, and differentiated migration strategy of males and females. In addition, we found male-skewed sex proportions, with a tendency to an equalised ratio in more southern stopover sites. This may indicate a male bias in the global population or different migration strategies of the sexes. Differential migration may cause the age and sex classes to be exposed differently to various threats affecting demographic structure of the species.

  5. Oak Ridge Reservation Bird Records and Population Trends

    Energy Technology Data Exchange (ETDEWEB)

    Roy, W. K. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Giffen, N. R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wade, M. C. [CDM Smith (United States); Haines, A. M. [Xcel Engineering, Inc.(United States); Evans, J. W. [Tennessee WIldlife Resources Agency (WRA), Nashville, TN (United States); Jett, R. T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2014-09-01

    Bird data have been collected through surveys, environmental assessments, and other observations for decades in the Oak Ridge National Environmental Research Park, located on the US Department of Energy’s Oak Ridge Reservation (ORR) in East Tennessee. Birds were recorded in a variety of habitats, including wetlands, interior forests, grasslands, ponds, corridors, forest edges, and more. Most of the information was gathered from waterfowl surveys conducted from 1990 to 2008, from Partners in Flight (PIF) breeding bird surveys conducted from 1995 to 2013, and from past publications and research on Reservation birds. We have also included our own observations and, in a few instances, credible observations of ORR birds of which we have been made aware through eBird or discussions with area ornithologists and bird watchers. For the period 1950-2014, we were able to document 228 species of birds on the ORR. Several of these species are known from historic records only, while others were not known to have ever occurred on the Reservation until recently. This report does not include PIF breeding bird data from the 2014 season or any records after July 2014. Twenty-two species--approximately 10% of the total number of species observed--have state-listed status in Tennessee as endangered, threatened, or in need of management. Of the 228 species we documented, 120 are believed to be breeding birds on the ORR.

  6. Oak Ridge Reservation Bird Records and Population Trends

    Energy Technology Data Exchange (ETDEWEB)

    Roy, W. Kelly [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Giffen, Neil R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wade, Murray [CDM Smith, Inc., Knoxville, TN (United States); Haines, Angelina [Xcel Engineering, Inc., Oak Ridge, TN (United States); Evans, James W. [Tennessee Wildlife Resources Agency, Nashville, TN (United States); Jett, Robert Trent [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2014-11-01

    Bird data have been collected through surveys, environmental assessments, and other observations for decades in the Oak Ridge National Environmental Research Park, located on the US Department of Energy s Oak Ridge Reservation (ORR) in East Tennessee. Birds were recorded in a variety of habitats, including wetlands, interior forests, grasslands, ponds, corridors, forest edges, and more. Most of the information was gathered from waterfowl surveys conducted from 1990 to 2008, from Partners in Flight (PIF) breeding bird surveys conducted from 1995 to 2013, and from past publications and research on Reservation birds. We have also included our own observations and, in a few instances, credible observations of ORR birds of which we have been made aware through eBird or discussions with area ornithologists and bird watchers. For the period 1950 2014, we were able to document 228 species of birds on the ORR. Several of these species are known from historic records only, while others were not known to have ever occurred on the Reservation until recently. This report does not include PIF breeding bird data from the 2014 season or any records after July 2014. Twenty-two species approximately 10% of the total number of species observed have state-listed status in Tennessee as endangered, threatened, or in need of management. Of the 228 species we documented, 120 are believed to be breeding birds on the ORR.

  7. Birds and wind power. Technical report 1977-1982; Faglar och vindkraft. Teknisk rapport 1977-1982

    Energy Technology Data Exchange (ETDEWEB)

    Karlsson, Johnny

    1983-02-15

    The impact of wind power plants on birds has been studied. The risk of migrating birds colliding with high buildings has been investigated. Different hazards and accidents are described and reported in 12 appendices. Preliminary data from the sites of wind power plants are presented.

  8. Technology on the Move: Recent and Forthcoming Innovations for Tracking Migratory Birds

    DEFF Research Database (Denmark)

    Bridge, Eli S.; Thorup, Kasper; Bowlin, Melissa S.

    2011-01-01

    networks, solar geolocation, radar, and information technology are improving our understanding of when and where birds go during their annual cycles and informing numerous scientific disciplines, including evolutionary biology, population ecology, and global change. The recent developments described......Basic questions about the life histories of migratory birds have confounded scientists for generations, yet we are nearing an era of historic discovery as new tracking technologies make it possible to determine the timing and routes of an increasing number of bird migrations. Tracking small flying...

  9. Food abundance does not determine bird use of early-successional habitat.

    Energy Technology Data Exchange (ETDEWEB)

    Champlin, Tracey B.; Kilgo, John C.; Moorman, Christopher E.

    2009-06-01

    Abstract. Few attempts have been made to experimentally address the extent to which temporal or spatial variation in food availability influences avian habitat use. We used an experimental approach to investigate whether bird use differed between treated (arthropods reduced through insecticide application) and control (untreated) forest canopy gaps within a bottomland hardwood forest in the Upper Coastal Plain of South Carolina, USA. Gaps were two- to three-year-old group selection timber harvest openings of three sizes (0.13, 0.26, and 0.50 ha). Our study was conducted during four bird use periods (spring migration, breeding, post-breeding, and fall migration) in 2002 and 2003. Arthropods were reduced in treated gaps by 68% in 2002 and 73% in 2003. We used mist-netting captures and foraging attack rates to assess the influence of arthropod abundance on avian habitat use. Evidence that birds responded to arthropod abundance was limited and inconsistent. In 2002, we generally captured more birds in treated gaps of the smallest size (0.13 ha) and fewer birds in treated gaps of the larger sizes. In 2003, we recorded few differences in the number of captures in treated and control gaps. Foraging attack rates generally were lower in treated than in control gaps, indicating that birds were able to adapt to the reduced food availability and remain in treated gaps. We conclude that arthropod abundance was not a proximate factor controlling whether forest birds used our gaps. The abundance of food resources may not be as important in determining avian habitat selection as previous research has indicated, at least for passerines in temperate subtropical regions.

  10. Bird Survey in Storruns windfarm in Jaemtland; Faagelundersoekning vid Storruns vindkraftanlaeggning Jaemtland

    Energy Technology Data Exchange (ETDEWEB)

    Falkdalen, Ulla; Falkdalen Lindahl, Lars; Nygaard, Torgeir

    2013-08-15

    A survey of the bird populations in Oldfjaellen in Jaemtland county, Sweden, was initiated in 2003 prior to the construction of a wind-farm on two adjacent hills, Storrun and Froesoerun by the lake Oevre Oldsjoen. After a gap in the surveys in 2004, comprehensive studies were continued during 2005 - 2008, prior to the construction. The construction-work started during autumn 2008, and the turbines were erected during 2009. Power production was started during the autumn of 2009. The post-construction bird studies were carried out in 2010 and 2011. This report summarizes all the studies that were performed before and after the construction of the wind-farm. Many of the separate studies were made using a BACI method (Before-After-Control-Impact) enabling comparisons of the situation before and after development, using a control area. In addition, a study of collision rates and scavenger removal rates is reported. As expected, the movement and migration of birds over Storrun was of rather limited magnitude. Although the majority of observations during the investigated periods spring and autumn are assumed to be migrating birds, larger flocks of birds are rare in the area. Ca. 20 % of all the birds that passed through or near the wind-farm area flew in heights comparable to the rotor-swept zone. However, more than 40 % of the raptors and waders passed through in that zone, which implies a collision risk. These two groups of birds have shown to be particularly prone to collisions with rotor blades in other studies.

  11. West Nile Virus in Resident Birds from Yucatan, Mexico.

    Science.gov (United States)

    Chaves, Andrea; Sotomayor-Bonilla, Jesus; Monge, Otto; Ramírez, Abigaíl; Galindo, Francisco; Sarmiento-Silva, Rosa Elena; Gutiérrez-Espeleta, Gustavo A; Suzán, Gerardo

    2016-01-01

    West Nile virus (WNV) in the Americas is thought to be transported at large spatial scales by migratory birds and locally spread and amplified by resident birds. Local processes, including interspecific interactions and dominance of passerine species recognized as competent reservoirs, may boost infection and maintain endemic cycles. Change in species composition has been recognized as an important driver for infection dynamics. Due to migration and changes in species diversity and composition in wintering grounds, changes in infection prevalence are expected. To these changes, we used PCR to estimate the prevalence of WNV in wild resident birds during the dry and rainy seasons of 2012 in Yucatan, Mexico. Serum samples were obtained from 104 wild birds, belonging to six orders and 35 species. We detected WNV in 14 resident birds, representing 11 species and three orders. Prevalences by order was Passeriformes (27%), Columbiformes (6%), and Piciformes (33%). Resident birds positive to WNV from Yucatan may be indicative of local virus circulation and evidence of past virus transmission activity.

  12. Bioaccumulation of polonium 210Po in marine birds

    International Nuclear Information System (INIS)

    Skwarzec, B.; Fabisiak, J.

    2007-01-01

    The aim of this work was to determine the 210 Po content in marine birds which permanently or temporally live in the Polish part of the Baltic Sea. We chose 11 species of sea birds: three species permanently residing at southern Baltic Sea, four species of wintering birds and three species of migrating birds. The results show that the polonium is non-uniformly distributed in the marine birds. The highest activities of 210 Po were observed in feathers, muscles and liver and the lowest in skin and skeleton. Species of birds that eat crustaceans, molluscs, fish and plants (long-tailed duck Clangula hyemalis, white-winged scoter Melanitta fusca) accumulated more polonium than species that eat mainly fish (great cormorant Phalacrocorax carbo, common guillemot Uria aalge) or plants (tufted duck Aythya fuligula). Moreover, about 63% of the 210 Po that was located in feathers of razorbil (Alca torda) and long-tailed duck (C. hyemalis) was apparently adsorbed, suggesting an external source such as the air. It means that the adsorption of 210 Po on the feather surface may be an important transfer from air to water

  13. Integrating meteorology into research on migration

    NARCIS (Netherlands)

    Shamoun-Baranes, J.; Bouten, W.; van Loon, E.E.

    2010-01-01

    Atmospheric dynamics strongly influence the migration of flying organisms. They affect, among others, the onset, duration and cost of migration, migratory routes, stop-over decisions, and flight speeds en-route. Animals move through a heterogeneous environment and have to react to atmospheric

  14. Assessment of bird populations in a high quality savanna/woodland: a banding approach

    Science.gov (United States)

    Wilmore, Sandra L.; Glowacki, Gary A.; Grundel, Ralph

    2005-01-01

    Between 1999 and 2004, Save the Dunes Conservation Fund's Miller Woods Bird Banding Program monitored migrating and breeding bird populations within a high quality black oak, dry-mesic sand savanna/woodland with ridge and swale topography. The objectives of this program were to collect consistent and reliable demographic and abundance data on the bird populations, to investigate long-term population trends, and to contribute to improved land management decisions at regional and national scales. The technique employed involved capturing birds in mist nets that were deployed for set periods of time at 17 net sites in two banding areas in Miller Woods.

  15. Detailed description of the Ócsa Bird Ringing Station, Hungary

    Directory of Open Access Journals (Sweden)

    Csörgő Tibor

    2016-12-01

    Full Text Available The present paper acts as an introduction to a series that will describe the exploratory analyses of migration phenology and morphometrics of the most common passerine species at the Ócsa Bird Ringing Station. This station is situated in the Ócsa Landscape Protection Area that belongs to the Duna–Ipoly National Park, Hungary. The area is somewhat cooler and more humid than the surrounding agricultural fields and tree plantations, covered by a mosaic of diverse hygrophilous vegetation patches. Bird trapping is mostly based on Japanese mist-net lines crossing different plant communities. During the period of 1984–2015, a total of 422,862 birds were trapped and ringed here, while 202,739 local, 1,235 within country, and 443 foreign recaptures were also recorded. Each bird is characterized by the following data: location and time of capture, species, age, sex, scores of fat, pectoral muscle, wing tip abrasion, and moult, length of wing, 3rd primary, and tail, and body mass. After subjected to a rigorous quality check, digital data are deposited in the archive of the Hungarian Bird Ringing Centre, and the EURING data base. From time to time, other research projects also utilized the accessibility of wild birds captured here, thus collection of blood samples, ecto- and endoparasites was carried out at the station. The relatively long time span, large number of species and individuals, and the readily available environmental (weather, vegetation, etc. data makes the avian data collected here a suitable base for studies of various disciplines like capture methodology, habitat preferences, breeding, migration, and wintering, effects of weather and climate change, and epidemiology of viruses and parasites.

  16. Migratory birds and West Nile virus

    Czech Academy of Sciences Publication Activity Database

    Rappole, J. H.; Hubálek, Zdeněk

    2003-01-01

    Roč. 94, s1 (2003), s. 47-58 ISSN 1364-5072. [Conference of Society for Applied Microbiology (U.K.) "Pathogens in the Environment and Changing Ecosystems". Nottingham, 08.07.2002-11.07.2002] Institutional research plan: CEZ:AV0Z6093917 Keywords : West Nile virus * bird migration Subject RIV: FN - Epidemiology, Contagious Diseases ; Clinical Immunology Impact factor: 1.743, year: 2003

  17. Landbird migration in the American West: Recent progress and future research directions

    Science.gov (United States)

    Carlisle, J.D.; Skagen, S.K.; Kus, B.E.; van Riper, Charles; Paxton, K.L.; Kelly, J.F.

    2009-01-01

    Our knowledge of avian behaviors during the nonbreeding period still lags behind that of the breeding season, but the last decade has witnessed a proliferation in research that has yielded significant progress in understanding migration patterns of North American birds. And, although historically the great majority of migration research has been conducted in the eastern half of the continent, there has been much recent progress on aspects of avian migration in the West. In particular, expanded use of techniques such as radar, plasma metabolites, mist-netting, count surveys, stable isotopes, genetic data, and animal tracking, coupled with an increase in multi-investigator collaborations, have all contributed to this growth of knowledge. There is increasing recognition that migration is likely the most limiting time of year for migratory birds, increasing the importance of continuing to decipher patterns of stopover ecology, identifying critical stopover habitats, and documenting migration routes in the diverse and changing landscapes of the American West. Here, we review and briefly synthesize the latest findings and advances in avian migration and consider research needs to guide future research on migration in the West. ?? 2009 by The Cooper Ornithological Society. All rights reserved.

  18. Fluid dynamics of flapping aquatic flight in the bird wrasse: three-dimensional unsteady computations with fin deformation.

    Science.gov (United States)

    Ramamurti, Ravi; Sandberg, William C; Löhner, Rainald; Walker, Jeffrey A; Westneat, Mark W

    2002-10-01

    Many fishes that swim with the paired pectoral fins use fin-stroke parameters that produce thrust force from lift in a mechanism of underwater flight. These locomotor mechanisms are of interest to behavioral biologists, biomechanics researchers and engineers. In the present study, we performed the first three-dimensional unsteady computations of fish swimming with oscillating and deforming fins. The objective of these computations was to investigate the fluid dynamics of force production associated with the flapping aquatic flight of the bird wrasse Gomphosus varius. For this computational work, we used the geometry of the wrasse and its pectoral fin, and previously measured fin kinematics, as the starting points for computational investigation of three-dimensional (3-D) unsteady fluid dynamics. We performed a 3-D steady computation and a complete set of 3-D quasisteady computations for a range of pectoral fin positions and surface velocities. An unstructured, grid-based, unsteady Navier-Stokes solver with automatic adaptive remeshing was then used to compute the unsteady flow about the wrasse through several complete cycles of pectoral fin oscillation. The shape deformation of the pectoral fin throughout the oscillation was taken from the experimental kinematics. The pressure distribution on the body of the bird wrasse and its pectoral fins was computed and integrated to give body and fin forces which were decomposed into lift and thrust. The velocity field variation on the surface of the wrasse body, on the pectoral fins and in the near-wake was computed throughout the swimming cycle. We compared our computational results for the steady, quasi-steady and unsteady cases with the experimental data on axial and vertical acceleration obtained from the pectoral fin kinematics experiments. These comparisons show that steady state computations are incapable of describing the fluid dynamics of flapping fins. Quasi-steady state computations, with correct incorporation of

  19. Economic impotance of flying visitors: migratory birds | Egwumah ...

    African Journals Online (AJOL)

    ... are also capable of producing oil. Nature based tourism and recreation, such as the viewing of wildlife coupled with; management of migratory birds promotes market for other industrial goods such as lead shot, guns and binocular. Keywords: Migration; Recreation and Tourism; Trophies; Ornament; Food; Production of Oil ...

  20. Geographical and temporal flexibility in the response to crosswinds by migrating raptors.

    Science.gov (United States)

    Klaassen, Raymond H G; Hake, Mikael; Strandberg, Roine; Alerstam, Thomas

    2011-05-07

    Wind and ocean currents may potentially have important effects on travelling animals, as an animal which does not respond to lateral flow will be drifted from its intended direction of movement. By analysing daily movements of migrating ospreys Pandion haliaetus and marsh harriers Circus aeruginosus, as recorded by satellite telemetry, in relation to global wind data, we showed that these raptors allow on average 47 per cent drift. Furthermore, our analyses revealed significant geographical and temporal variation in the response to crosswinds. During some parts of the migration, the birds drifted and in other parts they compensated or even overcompensated. In some regions, the response of marsh harriers depended on the wind direction. They drifted when the wind came from one side and (over)compensated when the wind came from the opposite side, and this flexible response was different in different geographical regions. These results suggest that migrating raptors modulate their response to crosswinds at different places and times during their travels and show that individual birds use a much more varied repertoire of behavioural responses to wind than hitherto assumed. Our results may also explain why contrasting and variable results have been obtained in previous studies of the effect of wind on bird migration.

  1. Number of Migration Scenarios Passing through each HUC (future)

    Data.gov (United States)

    U.S. Environmental Protection Agency — Forest dwelling neotropical migratory birds require intact forested stopovers during migration. The number of paths that pass through a HUC highlight that huc's...

  2. Transoceanic migration by a 12 g songbird.

    Science.gov (United States)

    DeLuca, William V; Woodworth, Bradley K; Rimmer, Christopher C; Marra, Peter P; Taylor, Philip D; McFarland, Kent P; Mackenzie, Stuart A; Norris, D Ryan

    2015-04-01

    Many fundamental aspects of migration remain a mystery, largely due to our inability to follow small animals over vast spatial areas. For more than 50 years, it has been hypothesized that, during autumn migration, blackpoll warblers (Setophaga striata) depart northeastern North America and undertake a non-stop flight over the Atlantic Ocean to either the Greater Antilles or the northeastern coast of South America. Using miniaturized light-level geolocators, we provide the first irrefutable evidence that the blackpoll warbler, a 12 g boreal forest songbird, completes an autumn transoceanic migration ranging from 2270 to 2770 km (mean ± s.d.: 2540 ± 257) and requiring up to 3 days (62 h ± 10) of non-stop flight. This is one of the longest non-stop overwater flights recorded for a songbird and confirms what has long been believed to be one of the most extraordinary migratory feats on the planet. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  3. The effect of the Sep wind park near Oosterbierum, Friesland, The Netherlands, on birds. De invloed van de Sep-proefwindcentrale te Oosterbierum (Friesland) op vogels; Deel 4: Verstoring

    Energy Technology Data Exchange (ETDEWEB)

    Winkelman, J E

    1992-01-01

    The title study concerns the period 1984-1991. The wind park consists of 18 three-bladed 300 kW horizontal axis wind turbines of 35 meters height, and a rotor diameter of 30 meters, seven meteorological towers, and three cluster and control buildings. Aspects studied included disturbance of breeding, resting or feeding, and migrating birds, behavior of birds approaching the wind turbines during the day and night, and bird victims due to collision with the wind turbines and the meteorological towers. In this report attention is paid to the disturbance of the bird's biotope. The results show that four species of grassland birds, breeding in the park, were hardly disturbed by the wind turbines. For feeding and resting birds, however, disturbance effects were noted, even at a distance of 500 meters from the outside wind turbine array. The present number of bird species reduced 60-95%, dependent on the species, after the wind park was put into operation. Also the behavior of migrating birds was influenced by the wind park, showed in clustering of groups or avoiding the wind park, sometimes up to 67% of the birds did so. It is therefore recommended not to implement new wind parks in important bird migration and bird feeding or bird resting areas. Bird popular areas, however, are mostly windy areas. 15 figs., 25 tabs., 56 app., 128 refs.

  4. Rice production systems and avian influenza: Interactions between mixed-farming systems, poultry and wild birds

    Science.gov (United States)

    Muzaffar, S.B.; Takekawa, John Y.; Prosser, D.J.; Newman, S.H.; Xiao, X.

    2010-01-01

    Wild waterfowl are the reservoir for avian influenza viruses (AIVs), a family of RNA viruses that may cause mild sickness in waterbirds. Emergence of H5N1, a highly pathogenic avian influenza (HPAI) strain, causing severe disease and mortality in wild birds, poultry and humans, had raised concerns about the role of wild birds in possible transmission of the disease. In this review, the link between rice production systems, poultry production systems, and wild bird ecology is examined to assess the extent to which these interactions could contribute towards the persistence and evolution of HPAI H5N1. The rice (Oryza sativa) and poultry production systems in Asia described, and then migration and movements of wild birds discussed. Mixed farming systems in Asia and wild bird movement and migration patterns create opportunities for the persistence of low pathogenic AIVs in these systems. Nonetheless, there is no evidence of long-term persistence of HPAI viruses (including the H5N1 subtype) in the wild. There are still significant gaps in the understanding of how AIVs circulate in rice systems. A better understanding of persistence of AIVs in rice farms, particularly of poultry origins, is essential in limiting exchange of AIVs between mixed-farming systems, poultry and wild birds.

  5. Breeding of marine birds on Farwa Island, western Libya | Etayeb ...

    African Journals Online (AJOL)

    Breeding of marine birds on Farwa Island, western Libya. ... They provide food, shelter and nesting grounds for many avifauna during their migration ... northern part of the island and at Ras-Attalgha, beside the plant cover of the island itself.

  6. Flight response to spatial and temporal correlates informs risk from wind turbines to the California Condor

    Science.gov (United States)

    Poessel, Sharon; Brandt, Joseph; Mendenhall, Laura C.; Braham, Melissa A.; Lanzone, Michael J.; McGann, Andrew J.; Katzner, Todd

    2018-01-01

    Wind power is a fast-growing energy resource, but wind turbines can kill volant wildlife, and the flight behavior of obligate soaring birds can place them at risk of collision with these structures. We analyzed altitudinal data from GPS telemetry of critically endangered California Condors (Gymnogyps californianus) to assess the circumstances under which their flight behavior may place them at risk from collision with wind turbines. Condor flight behavior was strongly influenced by topography and land cover, and birds flew at lower altitudes and closer to the rotor-swept zone of wind turbines when over ridgelines and steep slopes and over forested and grassland cover types. Condor flight behavior was temporally predictable, and birds flew lower and closer to the rotor-swept zone during early morning and evening hours and during the winter months, when thermal updrafts were weakest. Although condors only occasionally flew at altitudes that placed them in the rotor-swept zone of turbines, they regularly flew near or within wind resource areas preferred by energy developers. Practitioners aiming to mitigate collision risk to this and other soaring bird species of conservation concern can consider the manner in which flight behavior varies temporally and in response to areas of high topographic relief and proximity to nocturnal roosting sites. By contrast, collision risk to large soaring birds from turbines should be relatively lower over flatter and less rugged areas and in habitat used during daytime soaring.

  7. Post-breeding migration and connectivity of red knots in the Western Atlantic

    Science.gov (United States)

    Lyons, James E.; Winn, Bradford; Keyes, Timothy; Kalasz, Kevin S.

    2018-01-01

    Red knots (Calidris canutus rufa) have 3 distinct nonbreeding regions: 1 in the southeastern United States and Caribbean, another on the northeast coast of Brazil in the Maranhão region, and a third along the Patagonian coasts of Chile and Argentina. Effective conservation and recovery of this threatened long-distance migrant will require knowledge of population structure, migration ecology, and abundance and distribution throughout the annual cycle. We conducted a stopover population and biogeographic assessment of knots at the Altamaha River Delta, Georgia, an important stopover area in the southeastern United States. We estimated stopover population size and stopover duration during post-breeding migration in 2011 at the Altamaha study area using mark-resight data, and we inferred nonbreeding regions for this stopover population using stable isotope ratios of carbon and nitrogen in feathers, and observations (sightings and captures) during boreal winter from across the hemisphere. With an integrated Bayesian analysis of all these data, we also estimated the number of birds in the southeastern United States and northern Brazil during boreal winter. For mark-resight analyses in Georgia, we made observations of marked individuals during 14 weeks from early August to early November 2011 and detected 814 individually marked birds. We used the Jolly-Seber mark-recapture model and estimated the southbound passage population at approximately 23,400 red knots. In ongoing studies elsewhere, isotope samples were collected from 175 (21%) of the 814 birds detected in our study, and ≥1 sighting or capture record during boreal winter was located in data repositories for 659 birds (81%). Isotopic signatures and boreal winter records indicate that the majority (82–96%) of the birds that stopped at the Altamaha Delta spend the boreal winter in the northern part of the nonbreeding range (southeast USA, Caribbean, and northern Brazil). Knots migrating to the southeastern

  8. Olfactory lateralization in homing pigeons: a GPS study on birds released with unilateral olfactory inputs.

    Science.gov (United States)

    Gagliardo, Anna; Filannino, Caterina; Ioalè, Paolo; Pecchia, Tommaso; Wikelski, Martin; Vallortigara, Giorgio

    2011-02-15

    A large body of evidence has shown that pigeons rely on an olfactory-based navigational map when homing from unfamiliar locations. Previous studies on pigeons released with one nostril occluded highlighted an asymmetry in favour of the right nostril, particularly concerning the initial orientation performance of naïve birds. Nevertheless, all pigeons experiencing only unilateral olfactory input showed impaired homing, regardless of the side of the occluded nostril. So far this phenomenon has been documented only by observing the birds' vanishing bearings. In the present work we recorded the flight tracks of pigeons with previous homing experience equipped with a GPS data logger and released from an unfamiliar location with the right or the left nostril occluded. The analysis of the tracks revealed that the flight path of the birds with the right nostril occluded was more tortuous than that of unmanipulated controls. Moreover, the pigeons smelling with the left nostril interrupted their journey significantly more frequently and displayed more exploratory activity than the control birds, e.g. during flights around a stopover site. These data suggest a more important involvement of the right olfactory system in processing the olfactory information needed for the operation of the navigational map.

  9. Bird's nest versus the Kimray-Greenfield inferior vena cava filter: Randomized clinical study

    International Nuclear Information System (INIS)

    Athanasoulis, C.A.; Roberts, A.C.; Brown, K.; Geller, S.C.; Waltman, A.C.; Eckstein, M.R.

    1987-01-01

    A randomized clinical study was conducted comparing the percutaneously introduced bird's nest inferior vena cava (IVC) filter and the Kimray-Greenfield IVC filter. Study end points included recurrent pulmonary embolism, new or worse leg venous stasis symptoms, IVC thrombosis, and ease of filter introduction. Of the 109 patients in the study, 58 were randomly assigned to the BN and 51 to the KG filter. Demographic factors were comparable between the two groups. Follow-up entailed cavography, noninvasive assessment of the femoral veins, and standardized telephone interviews. The follow-up period was extended to 1 year after filter insertion. Results for the bird's nest versus the Kimray-Greenfield filter respectively were as follows: death due to massive pulmonary embolism, 3% versus 5%; recurrent pulmonary embolism, 1.5% versus 7.5%; filter migration, 1.1% versus 0.0%; IVC thrombosis, 6% versus 2.5%; new or worse leg edema, 28.5% versus 22%; ease of introduction (qualitative), maximal versus minimal; patient discomfort (qualitative), minimal versus maximal. The authors conclude the bird's nest filter is better than the Kimray-Greenfield filter in terms of prevention of recurrent pulmonary embolism and ease of introduction. In terms of venous stasis, the bird's nest filter is not better and may be worse than the Kimray-Greenfield filter. Filter migration is a problem with the bird's nest filter

  10. Intense flight and endotoxin injection elicit similar effects on leukocyte distributions but dissimilar effects on plasma-based immunological indices in pigeons

    NARCIS (Netherlands)

    Matson, Kevin D.; Horrocks, Nicholas P. C.; Tieleman, B. Irene; Haase, Eberhard

    Most birds rely on flight for survival. Yet as an energetically taxing and physiologically integrative process, flight has many repercussions. Studying pigeons (Columba livia) and employing physiological and immunological indices that are relevant to ecologists working with wild birds, we determined

  11. Intense flight and endotoxin injection elicit similar effects on leukocyte distributions but dissimilar effects on plasma-based immunoplogical indices in pigeons

    NARCIS (Netherlands)

    Matson, K.D.; Horrocks, N.P.C.; Tieleman, B.I.; Haase, E.

    2012-01-01

    Most birds rely on flight for survival. Yet as an energetically taxing and physiologically integrative process, flight has many repercussions. Studying pigeons (Columba livia) and employing physiological and immunological indices that are relevant to ecologists working with wild birds, we determined

  12. Intense flight and endotoxin injection elicit similar effects on leukocyte distributions but dissimilar effects on plasma-based immunological indices in pigeons

    NARCIS (Netherlands)

    Matson, Kevin D.; Horrocks, Nicholas P. C.; Tieleman, B. Irene; Haase, Eberhard

    2012-01-01

    Most birds rely on flight for survival. Yet as an energetically taxing and physiologically integrative process, flight has many repercussions. Studying pigeons (Columba livia) and employing physiological and immunological indices that are relevant to ecologists working with wild birds, we determined

  13. Proceedings of the Wind Energy and Birds/Bats Workshop: Understanding and Resolving Bird and Bat Impacts

    Energy Technology Data Exchange (ETDEWEB)

    Schwartz, Susan Savitt (ed.)

    2004-09-01

    Most conservation groups support the development of wind energy in the US as an alternative to fossil and nuclear-fueled power plants to meet growing demand for electrical energy. However, concerns have surfaced over the potential threat to birds, bats, and other wildlife from the construction and operation of wind turbine facilities. Co-sponsored by the American Bird Conservancy (ABC) and the American Wind Energy Association (AWEA), the Wind Energy and Birds/Bats Workshop was convened to examine current research on the impacts of wind energy development on avian and bat species and to discuss the most effective ways to mitigate such impacts. On 18-19 May 2004, 82 representatives from government, non-government organizations, private business, and academia met to (1) review the status of the wind industry and current project development practices, including pre-development risk assessment and post-construction monitoring; (2) learn what is known about direct, indirect (habitat), and cumulative impacts on birds and bats from existing wind projects; about relevant aspects of bat and bird migration ecology; about offshore wind development experience in Europe; and about preventing, minimizing, and mitigating avian and bat impacts; (3) review wind development guidelines developed by the USFWS and the Washington State Department of Fish and Wildlife; and (4) identify topics needing further research and to discuss what can be done to ensure that research is both credible and accessible. These Workshop Proceedings include detailed summaries of the presentations made and the discussions that followed.

  14. Metabolism during flight in two species of bats, Phyllostomus hastatus and Pteropus gouldii.

    Science.gov (United States)

    Thomas, S P

    1975-08-01

    The energetic cost of flight in a wind-tunnel was measured at various combinations of speed and flight angle from two species of bats whose body masses differ by almost an order of magnitude. The highest mean metabolic rate per unit body mass measured from P. hastatus (mean body mass, 0.093 kg) was 130.4 Wkg-1, and that for P. gouldii (mean body mass, 0.78 kg) was 69.6 Wkg-1. These highest metabolic rates, recorded from flying bats, are essentially the same as those predicted for flying birds of the same body masses, but are from 2.5 to 3.0 times greater than the highest metabolic rates of which similar-size exercising terrestrial mammals appear capable. The lowest mean rate of energy utilization per unit body mass P. hastatus required to sustain level flight was 94.2 Wkg-1 and that for P. gouldii was 53.4 Wkg-1. These data from flying bats together with comparable data for flying birds all fall along a straight line when plotted on double logarithmic coordinates as a function of body mass. Such data show that even the lowest metabolic requirements of bats and birds during level flight are about twice the highest metabolic capabilities of similar-size terrestrial mammals. Flying bats share with flying birds the ability to move substantially greater distance per unit energy consumed than walking or running mammals. Calculations show that P. hastatus requires only one-sixth the energy to cover a given distance as does the same-size terrestrial mammal, while P. gouldii requires one-fourth the energy of the same-size terrestrial mammal. An empirically derived equation is presented which enables one to make estimates of the metabolic rates of bats and birds during level flight in nature from body mass data alone. Metabolic data obtained in this study are compared with predictions calculated from an avian flight theory.

  15. Biometry and phenology of two sibling Phylloscopus warblers on their circum-Mediterranean migrations.

    Science.gov (United States)

    Zduniak, Piotr; Yosef, Reuven; Bensusan, Keith J; Perez, Charles E; Tryjanowski, Piotr

    2015-01-01

    The Mediterranean Sea is known as an ecological barrier for numerous migratory birds flying from European breeding grounds to African wintering sites. Birds generally avoid migration over open sea and fly over land. In the Mediterranean Basin, few land bridges or bottlenecks for migratory birds exist. The narrowest are at the western and eastern extremes: the Strait of Gibraltar and Israel. Comparative studies between these locations are extremely rare to date. Therefore, in order to elucidate the differences between the two flyways, we compared data collected simultaneously for two sister leaf warbler species, the Bonelli's Warbler complex, Phylloscopus bonelli and Phylloscopus orientalis, at ringing stations in the western Mediterranean Basin Gibraltar, and the eastern Eilat, Israel. Data on biometrics and passage dates of individuals trapped at Gibraltar and Eilat were used, and it was found that mean arrival date of Western Bonelli's Warblers at Gibraltar was 15 days later than Eastern Bonelli's Warblers at Eilat. Furthermore, Western Bonelli's Warblers had shorter wings than Eastern Bonelli's Warblers. On the other hand, birds in Eilat were in poorer body condition than individuals in Gibraltar. The comparison between geographically distant stop-over sites contributes to furthering our understanding of the development of migration strategies across ecological barriers in sibling species. Our study showed that populations that breed in southwestern Europe migrate through Gibraltar and winter in West Africa are able to accomplish migration in comparatively good body condition. This is in contrast to those that winter in East Africa, migrate through Israel and have to endure the combined challenge of crossing the Sahel, Sahara and Sinai deserts before reaching their breeding grounds across southeast Europe and southwest Asia. Hence, the discrepancies described between the western and the eastern flyway suggest that individuals in the west, in general, migrate

  16. Dark-Bellied Brent Geese Branta bernicla bernicla, as Recorded by Satellite Telemetry, do not Minimize Flight Distance During Spring Migration

    DEFF Research Database (Denmark)

    Green, M.; Alerstam, T.; Clausen, P.

    2002-01-01

    was tracked to the Yamal peninsula in 1998. Eight adult males were selected from a single catch of 75 to span the range of body mass observed on the date of capture (11 May 1999) and all but the lightest individual completed the first lap of the migratory flight to the White Sea, Russia, according to the time...... of six adult males). Only 7% of total time during spring migration was spent in active flight, as contrasted to c. 80% at long-term stopovers. Overall average travelling speed was 118 km day-1 (range 97-148). Including fattening prior to departure the rate of travel falls to 62 km day-1 (range 49...

  17. Southward autumn migration of waterfowl facilitates cross-continental transmission of the highly pathogenic avian influenza H5N1 virus

    Science.gov (United States)

    Xu, Yanjie; Gong, Peng; Wielstra, Ben; Si, Yali

    2016-08-01

    The highly pathogenic avian influenza subtype H5N1 (HPAI H5N1) is a worldwide zoonotic infectious disease, threatening humans, poultry and wild birds. The role of wild birds in the spread of HPAI H5N1 has previously been investigated by comparing disease spread patterns with bird migration routes. However, the different roles that the southward autumn and northward spring migration might play in virus transmission have hardly been explored. Using direction analysis, we analyze HPAI H5N1 transmission directions and angular concentration of currently circulating viral clades, and compare these with waterfowl seasonal migration directions along major waterfowl flyways. Out of 22 HPAI H5N1 transmission directions, 18 had both a southward direction and a relatively high concentration. Differences between disease transmission and waterfowl migration directions were significantly smaller for autumn than for spring migration. The four northward transmission directions were found along Asian flyways, where the initial epicenter of the virus was located. We suggest waterfowl first picked up the virus from East Asia, then brought it to the north via spring migration, and then spread it to other parts of world mainly by autumn migration. We emphasize waterfowl autumn migration plays a relatively important role in HPAI H5N1 transmission compared to spring migration.

  18. Respiratory evolution facilitated the origin of pterosaur flight and aerial gigantism.

    Directory of Open Access Journals (Sweden)

    Leon P A M Claessens

    Full Text Available Pterosaurs, enigmatic extinct Mesozoic reptiles, were the first vertebrates to achieve true flapping flight. Various lines of evidence provide strong support for highly efficient wing design, control, and flight capabilities. However, little is known of the pulmonary system that powered flight in pterosaurs. We investigated the structure and function of the pterosaurian breathing apparatus through a broad scale comparative study of respiratory structure and function in living and extinct archosaurs, using computer-assisted tomographic (CT scanning of pterosaur and bird skeletal remains, cineradiographic (X-ray film studies of the skeletal breathing pump in extant birds and alligators, and study of skeletal structure in historic fossil specimens. In this report we present various lines of skeletal evidence that indicate that pterosaurs had a highly effective flow-through respiratory system, capable of sustaining powered flight, predating the appearance of an analogous breathing system in birds by approximately seventy million years. Convergent evolution of gigantism in several Cretaceous pterosaur lineages was made possible through body density reduction by expansion of the pulmonary air sac system throughout the trunk and the distal limb girdle skeleton, highlighting the importance of respiratory adaptations in pterosaur evolution, and the dramatic effect of the release of physical constraints on morphological diversification and evolutionary radiation.

  19. Respiratory evolution facilitated the origin of pterosaur flight and aerial gigantism.

    Science.gov (United States)

    Claessens, Leon P A M; O'Connor, Patrick M; Unwin, David M

    2009-01-01

    Pterosaurs, enigmatic extinct Mesozoic reptiles, were the first vertebrates to achieve true flapping flight. Various lines of evidence provide strong support for highly efficient wing design, control, and flight capabilities. However, little is known of the pulmonary system that powered flight in pterosaurs. We investigated the structure and function of the pterosaurian breathing apparatus through a broad scale comparative study of respiratory structure and function in living and extinct archosaurs, using computer-assisted tomographic (CT) scanning of pterosaur and bird skeletal remains, cineradiographic (X-ray film) studies of the skeletal breathing pump in extant birds and alligators, and study of skeletal structure in historic fossil specimens. In this report we present various lines of skeletal evidence that indicate that pterosaurs had a highly effective flow-through respiratory system, capable of sustaining powered flight, predating the appearance of an analogous breathing system in birds by approximately seventy million years. Convergent evolution of gigantism in several Cretaceous pterosaur lineages was made possible through body density reduction by expansion of the pulmonary air sac system throughout the trunk and the distal limb girdle skeleton, highlighting the importance of respiratory adaptations in pterosaur evolution, and the dramatic effect of the release of physical constraints on morphological diversification and evolutionary radiation.

  20. Private lands habitat programs benefit California's native birds

    Directory of Open Access Journals (Sweden)

    Ryan T. DiGaudio

    2015-10-01

    Full Text Available To address the loss of wetlands and riparian forests in California, private lands habitat programs are available through U.S. federal and state government agencies to help growers, ranchers and other private landowners create and enhance wildlife habitat. The programs provide financial and technical assistance for implementing conservation practices. To evaluate the benefits of these programs for wildlife, we examined bird use of private wetlands, postharvest flooded croplands and riparian forests enrolled in habitat programs in the Central Valley and North Coast regions of California. We found that private Central Valley wetlands supported 181 bird species during the breeding season. During fall migration, postharvest flooded croplands supported wetland-dependent species and a higher density of shorebirds than did semipermanent wetlands. At the riparian sites, bird species richness increased after restoration. These results demonstrated that the programs provided habitat for the species they were designed to protect; a variety of resident and migratory bird species used the habitats, and many special status species were recorded at the sites.

  1. Global associations between birds and vane-dwelling feather mites.

    Science.gov (United States)

    Doña, Jorge; Proctor, Heather; Mironov, Sergey; Serrano, David; Jovani, Roger

    2016-11-01

    Understanding host-symbiont networks is a major question in evolutionary ecology. Birds host a great diversity of endo- and ectosymbiotic organisms, with feather mites (Arachnida: Acariformes: Analgoidea, Pterolichoidea) being among the most diverse of avian symbionts. A global approach to the ecology and evolution of bird-feather-mite associations has been hampered because of the absence of a centralized data repository. Here we present the most extensive data set of associations between feather mites and birds. Data include 12 036 records of 1887 feather mite species located on the flight feathers of 2234 bird species from 147 countries. Feather mites typically located inside quills, on the skin, or on downy body feathers are not included. Data were extracted from 493 published sources dating from 1882 to 2015. Data exploration shows that although most continents and bird families are represented, most bird species remain unexplored for feather mites. Nevertheless, this is the most comprehensive data set available for enabling global macroecological analyses of feather mites and their hosts, such as ecological network analyses. This metadata file outlines the structure of these data and provides primary references for all records used. © 2016 by the Ecological Society of America.

  2. The effect of the Sep wind park near Oosterbierum, Friesland, The Netherlands, on birds

    International Nuclear Information System (INIS)

    Winkelman, J.E.

    1992-01-01

    The title study concerns the period 1984-1991. The wind park consists of 18 three-bladed 300 kW horizontal axis wind turbines of 35 meters height, and a rotor diameter of 30 meters, seven meteorological towers, and three cluster and control buildings. Aspects studied included disturbance of breeding, resting or feeding, and migrating birds, behavior of birds approaching the wind turbines during the day and night, and bird victims due to collision with the wind turbines and the meteorological towers. This report deals with the results of searches for dead birds killed as a consequence of collisions with obstacles in the wind park in the spring of 1986-1991 and in the autumn of 1986-1988 and 1991. During the six spring periods and four autumn periods searches were made on 642 different days during which 2907 times an obstacle was searched for dead birds. During these days 76 birds were found (25 species), of which 36% were certainly or very probably killed as a result from a collision with a wind turbine, and 22% were possibly so. Of 34% the cause of death was unknown, and 7% died from other causes. Of the 76 birds found 17% were wounded but still alive. There were no nights with large kills. Also attention is paid to the distribution of the bird victims over the wind park area, their individual positions with regard to the obstacles, and the weather conditions in relation to the number of victims at a certain day. On average less than 0.1% of the birds passing the wind park during the night collided with an obstacle in the wind park, and less than 0.01% did so when the diurnal migration is included. When all resting and feeding birds are also added less than 0.008% collided in autumn (in spring less than 0.06%, breeding birds included). When the possible collisions are included these figures are 0.2%, 0.02%, 0.01% and 0.1% respectively. 9 figs., 22 tabs., 19 app., 83 refs

  3. Radioactivity measurements on migrating birds (Turdus philomelos) captured in the Comunidad Valenciana (Spain)

    International Nuclear Information System (INIS)

    Navarro, E.; Roldan, C.; Cervera, J.; Ferrero, J.L.

    1998-01-01

    The radionuclides 137 Cs, 134 Cs and 90 Sr have been measured in edible tissues and bones of migratory birds (song-thrushes, Turdus philomelos) from central and northern Europe and captured in the Comunidad Valenciana, Spain in the 1994 autumn-winter season. Eight years after the Chernobyl accident, extensive agricultural lands in Europe are still contaminated and this study shows that there was a transfer of radioactive isotopes to the captured migratory song-thrushes. The whole-body dose commitment to humans consuming these birds is estimated

  4. Spotted fever group rickettsiae in ticks of migratory birds in Romania.

    Science.gov (United States)

    Mărcuţan, Ioan-Daniel; Kalmár, Zsuzsa; Ionică, Angela Monica; D'Amico, Gianluca; Mihalca, Andrei Daniel; Vasile, Cozma; Sándor, Attila D

    2016-05-20

    Birds are important hosts and dispersers of parasitic arthropods and vector-borne zoonotic pathogens. Particularly migratory species may carry these parasites over long distances in short time periods. Migratory hotspots present ideal conditions to get a snapshot of parasite and pathogen diversity of birds migrating between continents. The aim of this study was to investigate the presence and diversity of Rickettsia spp. in ticks collected from birds at a migratory hot-spot in the Danube Delta, Romania, eastern Europe. DNA was extracted from ticks that were collected from migratory birds in the Danube Delta during migratory seasons in 2011-2012. Two 360 bp  fragments of the 16S ribosomal RNA gene and a 381 bp  fragment Gene gltA were PCR amplified and analyzed by sequence analysis (performed at Macrogen Europe, Amsterdam, The Netherlands). Nucleotide sequences were compared to reference sequences available in the GenBank database, using Basic Local Alignment Search Tool. Four hundred ticks of four different species were found on 11 bird species. The prevalence of Rickettsia spp. infection was 14 % (56/400, CI: 11.7-29.1), with significantly more nymphs hosting rickettsial infection compared to larvae (48 vs 7; P birds migrating through eastern Europe may carry ticks infected with a high diversity of rickettsial pathogens, with four Rickettsia spp. recorded. Migratory direction was important for pathogen burden, with seasonal differences in the occurrence of individual Rickettsia species. Here we report the first individual records of different Rickettsia spp. in H. concinna (R. monacensis), I. arboricola (R. helvetica, R. massiliae) and I. redikorzevi (R. helvetica) and also the first geographical record of occurrence of R. massiliae in Romania, representing the easternmost observation on the continent.

  5. Flexibility of continental navigation and migration in European mallards

    DEFF Research Database (Denmark)

    van Toor, Mariëlle L.; Hedenström, Anders; Waldenström, Jonas

    2013-01-01

    The ontogeny of continent-wide navigation mechanisms of the individual organism, despite being crucial for the understanding of animal movement and migration, is still poorly understood. Several previous studies, mainly conducted on passerines, indicate that inexperienced, juvenile birds may...... abilities. Here we tested whether immature mallard ducks correct for latitudinal displacement during fall migration within Europe. During two consecutive fall migration periods, we caught immature females on a stopover site in southeast Sweden, and translocated a group of them ca. 1,000 km to southern...... Germany. We followed the movements of the ducks via satellite GPS-tracking and observed their migration decisions during the fall and consecutive spring migration. The control animals released in Ottenby behaved as expected from banding recoveries: they continued migration during the winter and in spring...

  6. Collisional activation by MALDI tandem time-of-flight mass spectrometry induces intramolecular migration of amide hydrogens in protonated peptides

    DEFF Research Database (Denmark)

    Jørgensen, Thomas J D; Bache, Nicolai; Roepstorff, Peter

    2005-01-01

    of doubly protonated peptides that the original regioselective deuterium pattern of these peptides is completely erased (Jørgensen, T. J. D., Gårdsvoll, H., Ploug, M., and Roepstorff, P. (2005) Intramolecular migration of amide hydrogens in protonated peptides upon collisional activation. J. Am. Chem. Soc...... randomization among all exchangeable sites (i.e. all N- and O-linked hydrogens) also occurs upon high energy collisional activation of singly protonated peptides. This intense proton/deuteron traffic precludes the use of MALDI tandem time-of-flight mass spectrometry to obtain reliable information...

  7. Insights into Wilson's Warbler migration from analyses of hydrogen stable-isotope ratios

    Science.gov (United States)

    Jeffrey F. Kelly; Viorel Atudorei; Zachary D. Sharp; Deborah M. Finch

    2002-01-01

    Our ability to link the breeding locations of individual passerines to migration stopover sites and wintering locations is limited. Stable isotopes of hydrogen contained in bird feathers have recently shown potential in this regard. We measured hydrogen stable-isotope ratios (deltaD) of feathers from breeding, migrating, and wintering Wilson's Warblers. Analyses...

  8. No fly zones : oilsands mines use wide variety of bird deterrents

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, L.

    2010-10-15

    This article discussed the bird deterrent practices that several Canadian operators have in place at their tailings ponds. Regulations require that oilsands operators prevent birds from coming into contact with toxic tailings. Canadian Natural Resources Limited has a 2-man team constantly monitoring bird landings at its Horizon tailings pond. The team fires flares at birds or harasses them in boats to stop them from landing on the pond. Remote sensing technologies are used, including long-range acoustic devices, propane cannons, human effigies, balloons, and pyrotechnics. The vegetation around the pond is controlled to make the area inhospitable to birds, and highly desirable bird habitat was created as an alternative bird landing site. Following a high-mortality incident in 2008, Syncrude now deploys 190 shore-based sound canons at all tailings settling basins and open-water areas and uses scarecrows and effigies fitted with reflectors to deter waterfowl from landing. A radar-based migration monitoring system helps the company to optimize its deterrent system. At its Muskeg River Mine, Shell Canada Limited uses an on-demand radar-activated bird-deterrent program, which is what major airports use to deter birds. In the presence of a bird, the system launches a radio signal that sets off strobe lights, propane cannons, scarecrows, and mechanical models of falcons. 1 fig.

  9. Energetic Metabolism and Biochemical Adaptation: A Bird Flight Muscle Model

    Science.gov (United States)

    Rioux, Pierre; Blier, Pierre U.

    2006-01-01

    The main objective of this class experiment is to measure the activity of two metabolic enzymes in crude extract from bird pectoral muscle and to relate the differences to their mode of locomotion and ecology. The laboratory is adapted to stimulate the interest of wildlife management students to biochemistry. The enzymatic activities of cytochrome…

  10. Ontogeny of lift and drag production in ground birds.

    Science.gov (United States)

    Heers, Ashley M; Tobalske, Bret W; Dial, Kenneth P

    2011-03-01

    The juvenile period is often a crucial interval for selective pressure on locomotor ability. Although flight is central to avian biology, little is known about factors that limit flight performance during development. To improve understanding of flight ontogeny, we used a propeller (revolving wing) model to test how wing shape and feather structure influence aerodynamic performance during development in the precocial chukar partridge (Alectoris chukar, 4 to >100 days post hatching). We spun wings in mid-downstroke posture and measured lift (L) and drag (D) using a force plate upon which the propeller assembly was mounted. Our findings demonstrate a clear relationship between feather morphology and aerodynamic performance. Independent of size and velocity, older wings with stiffer and more asymmetrical feathers, high numbers of barbicels and a high degree of overlap between barbules generate greater L and L:D ratios than younger wings with flexible, relatively symmetrical and less cohesive feathers. The gradual transition from immature feathers and drag-based performance to more mature feathers and lift-based performance appears to coincide with ontogenetic transitions in locomotor capacity. Younger birds engage in behaviors that require little aerodynamic force and that allow D to contribute to weight support, whereas older birds may expand their behavioral repertoire by flapping with higher tip velocities and generating greater L. Incipient wings are, therefore, uniquely but immediately functional and provide flight-incapable juveniles with access to three-dimensional environments and refugia. Such access may have conferred selective advantages to theropods with protowings during the evolution of avian flight.

  11. Understanding the stopover of migratory birds: a scale dependent approach

    Science.gov (United States)

    Frank R. Moore; Mark S. Woodrey; Jeffrey J. Buler; Stefan Woltmann; Ted R. Simons

    2005-01-01

    The development of comprehensive conservation strategies and management plans for migratory birds depends on understanding migrant-habitat relations throughout the annual cycle, including the time when migrants stopover en route. Yet, the complexity of migration makes the assessment of habitat requirements and development of a comprehensive...

  12. The Importance of Corps of Engineers Lands to Migrating and Breeding Birds

    National Research Council Canada - National Science Library

    Fischer, Richard

    2001-01-01

    .... Birding is one of the fastest growing recreational activities in the United States. The economic impacts associated with this recreational activity on local communities have only recently been recognized...

  13. 9 CFR 93.104 - Certificate for pet birds, commercial birds, zoological birds, and research birds.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Certificate for pet birds, commercial birds, zoological birds, and research birds. 93.104 Section 93.104 Animals and Animal Products ANIMAL... (INCLUDING POULTRY) AND ANIMAL PRODUCTS IMPORTATION OF CERTAIN ANIMALS, BIRDS, FISH, AND POULTRY, AND CERTAIN...

  14. Heat dissipation during hovering and forward flight in hummingbirds.

    Science.gov (United States)

    Powers, Donald R; Tobalske, Bret W; Wilson, J Keaton; Woods, H Arthur; Corder, Keely R

    2015-12-01

    Flying animals generate large amounts of heat, which must be dissipated to avoid overheating. In birds, heat dissipation is complicated by feathers, which cover most body surfaces and retard heat loss. To understand how birds manage heat budgets during flight, it is critical to know how heat moves from the skin to the external environment. Hummingbirds are instructive because they fly at speeds from 0 to more than 12 m s(-1), during which they transit from radiative to convective heat loss. We used infrared thermography and particle image velocimetry to test the effects of flight speed on heat loss from specific body regions in flying calliope hummingbirds (Selasphorus calliope). We measured heat flux in a carcass with and without plumage to test the effectiveness of the insulation layer. In flying hummingbirds, the highest thermal gradients occurred in key heat dissipation areas (HDAs) around the eyes, axial region and feet. Eye and axial surface temperatures were 8°C or more above air temperature, and remained relatively constant across speeds suggesting physiological regulation of skin surface temperature. During hovering, birds dangled their feet, which enhanced radiative heat loss. In addition, during hovering, near-body induced airflows from the wings were low except around the feet (approx. 2.5 m s(-1)), which probably enhanced convective heat loss. Axial HDA and maximum surface temperature exhibited a shallow U-shaped pattern across speeds, revealing a localized relationship with power production in flight in the HDA closest to the primary flight muscles. We conclude that hummingbirds actively alter routes of heat dissipation as a function of flight speed.

  15. Bird Movements and Behaviors in the Gulf Coast Region: Relation to Potential Wind-Energy Developments

    Energy Technology Data Exchange (ETDEWEB)

    Morrison, M. L.

    2006-06-01

    The purpose of this paper is to discuss the possible impacts of wind development to birds along the lower Gulf Coast, including both proposed near-shore and offshore developments. The report summarizes wind resources in Texas, discusses timing and magnitude of bird migration as it relates to wind development, reviews research that has been conducted throughout the world on near- and offshore developments, and provides recommendations for research that will help guide wind development that minimizes negative impacts to birds and other wildlife resources.

  16. Long-term changes in migration timing of Song Thrush Turdus philomelos at the southern Baltic coast in response to temperatures on route and at breeding grounds.

    Science.gov (United States)

    Redlisiak, Michał; Remisiewicz, Magdalena; Nowakowski, Jarosław K

    2018-05-26

    Climate warming causes the advancement of spring arrival of many migrant birds breeding in Europe, but the effects on their autumn migration are less known. We aimed to determine any changes in the timing of Song Thrush captured during spring and autumn migrations at the Polish Baltic coast from 1975 to 2014, and if these were related to long-term changes of temperature at their breeding grounds and migration routes. The timing of spring migration at Hel ringing station in 1975-2014 did not show long-term advance, but they had responded to environmental conditions on the year-to-year basis. The warmer the temperatures were in April on their migration route, the earlier were the dates of the median and the end of spring migration at Hel. The beginning of autumn migration at the Mierzeja Wiślana ringing station advanced by 5 days between 1975 and 2014. The warmer the April on route, and the July at the Song Thrushes' breeding grounds, the earlier young birds began autumn migration across the Baltic coast. We suggest this was a combined effect of adults' migration and breeding early during warm springs and young birds getting ready faster for autumn migration during warm summers. The average time span of 90% of the autumn migration was extended by 5 days, probably because of early migration of young birds from first broods and late of those from second broods enabled by warm springs and summers. The response of Song Thrushes' migration timing to temperatures on route and at the breeding grounds indicated high plasticity in the species and suggested it might adapt well to climate changes.

  17. Virginia ESI: BIRDS (Bird Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for wading birds, shorebirds, waterfowl, raptors, diving birds, pelagic birds, passerine birds, and gulls...

  18. Neuroanatomy of flying reptiles and implications for flight, posture and behaviour.

    Science.gov (United States)

    Witmer, Lawrence M; Chatterjee, Sankar; Franzosa, Jonathan; Rowe, Timothy

    2003-10-30

    Comparison of birds and pterosaurs, the two archosaurian flyers, sheds light on adaptation to an aerial lifestyle. The neurological basis of control holds particular interest in that flight demands on sensory integration, equilibrium, and muscular coordination are acute. Here we compare the brain and vestibular apparatus in two pterosaurs based on high-resolution computed tomographic (CT) scans from which we constructed digital endocasts. Although general neural organization resembles birds, pterosaurs had smaller brains relative to body mass than do birds. This difference probably has more to do with phylogeny than flight, in that birds evolved from nonavian theropods that had already established trends for greater encephalization. Orientation of the osseous labyrinth relative to the long axis of the skull was different in these two pterosaur species, suggesting very different head postures and reflecting differing behaviours. Their enlarged semicircular canals reflect a highly refined organ of equilibrium, which is concordant with pterosaurs being visually based, aerial predators. Their enormous cerebellar floccular lobes may suggest neural integration of extensive sensory information from the wing, further enhancing eye- and neck-based reflex mechanisms for stabilizing gaze.

  19. Radar ornithology and the conservation of migratory birds

    Science.gov (United States)

    Sidney A. Gauthreaux; Carroll G. Belser

    2005-01-01

    It is possible to study with surveillance radar the movements of migrating birds in the atmosphere at different spatial scales. At a spatial scale within a range of 6 kilometers, high-resolution, 3-centimeter wavelength surveillance radar (e.g. BIRDRAD) can detect the departure of migrants from different types of habitat within a few kilometers of the radar. The radar...

  20. Can we explain vagrancy in Europe with the autumn migration phenology of Siberian warbler species in East Russia?

    Directory of Open Access Journals (Sweden)

    Bozó László

    2016-06-01

    Full Text Available We examined the autumn migration phenology of nine Siberian breeding songbirds: Thick-billed Warbler (Iduna aedon, Black-browed Reed Warbler (Acrocephalus bistrigiceps, Pallas’s Grasshopper Warbler (Locustella certhiola, Lanceolated Warbler (L. lanceolata, Yellow-browed Warbler (Phylloscopus inornatus, Arctic Warbler (Ph. borealis, Dusky Warbler (Ph. fuscatus, Radde’s Warbler (Ph. schwarzi, Two-barred Warbler (Ph. plumbeitarsus and compared the migration dynamic characteristics with their European occurrence time. The study was carried out within the Amur Bird Project in the Russian Far East along the river Amur at Muraviovka Park between 2011 and 2014. The birds were caught with mistnets and ringed with individually numbered rings. For the characterization of the migration, we used timing, the intervals and the peaks of the migration, the percentage of the recaptures and the average time between the first and the last captures. The timing of migration in the studied species differed in the timing, the intervals (30-67 days and the migration peaks (14 August - 17 September.

  1. Fuel use and metabolic response to endurance exercise: a wind tunnel study of a long-distance migrant shorebird

    OpenAIRE

    Jenni-Eiermann, Susanne; Jenni, Lukas; Kvist, Anders; Lindström, Åke; Piersma, Theunis; Visser, G. Henk

    2002-01-01

    This study examines fuel use and metabolism in a group of long-distance migrating birds, red knots Calidris canutus (Scolopacidae), flying under controlled conditions in a wind tunnel for up to 10 h. Data are compared with values for resting birds fasting for the same time. Plasma levels of free fatty acids, glycerol and uric acid were elevated during flight, irrespective of flight duration (1–10 h). Triglyceride levels, the estimated concentration of very-low-density lipoproteins (VLDLs) and...

  2. Status and management of neotropical migratory birds: Introduction

    Science.gov (United States)

    Deborah M.; Peter W. Stangel

    1993-01-01

    The future for neotropical migratory birds rests with our commitment and ability to provide them adequate habitat during all periods of their life cycle. Our commitment to this cause is apparent in the groundswell of interest in neotropical migrants and the many proactive and coopemtive partnerships resulting from the Partners in Flight - Aves de las Americas...

  3. Automated in situ monitoring of migratory birds at Germany's first offshore wind farm

    Energy Technology Data Exchange (ETDEWEB)

    Coppack, Timothy; Kulemeyer, Christoph; Schulz, Axel; Steuri, Thomas; Liechti, Felix

    2011-07-01

    Full text: Offshore wind farms may negatively affect migrating birds, especially at night, by increased photo tactic attraction and risk of collision. Under favourable weather conditions (clear skies, tail wind) the majority of migrants probably fly well above the reach of wind turbine blades. Under unfavourable conditions (sea fog, precipitation, head wind), however, nocturnal migrants could get attracted by brightly lit wind farms, and the risk of collision would hence increase. To assess these potential effects, migration rates and collision probabilities need to be empirically quantified at existing wind farms. This is not an easy task, given the setting and dimension of an offshore wind farm and the sheer quantity and diversity of small-bodied birds potentially passing by. Nocturnal passerine migrants are impossible to count accurately over extended periods with observational methods, and even classic radar technology fails to pro-vide hard-wired information. Complementing the 'Standards for Environmental Impact Assessment' issued by Germany.s Federal Maritime and Hydrographic Agency (BSH), we have developed and installed a novel radar system (BirdScan) on the research platform FINO 1, situated around 50 km offshore next to the wind farm 'alpha ventus' in the German North Sea. BirdScan operates on the basis of defined detection volumes (fixed radar beam), allowing a precise quantification of passerine and non-passerine radar echoes. Our study design includes alternating measurements within and outside the wind farm in order to assess avoidance and/or photo tactic aggregation behaviour of migrants under various weather situations. At the same time, we are investigating the photo tactic attraction of birds at a smaller spatial scale using motion-controlled infrared cameras directly mounted on the nacelle and shaft of a wind turbine. Through this approach, disoriented birds (and even bats) can be automatically ground-proofed and set in

  4. Energetic and biomechanical constraints on animal migration distance.

    Science.gov (United States)

    Hein, Andrew M; Hou, Chen; Gillooly, James F

    2012-02-01

    Animal migration is one of the great wonders of nature, but the factors that determine how far migrants travel remain poorly understood. We present a new quantitative model of animal migration and use it to describe the maximum migration distance of walking, swimming and flying migrants. The model combines biomechanics and metabolic scaling to show how maximum migration distance is constrained by body size for each mode of travel. The model also indicates that the number of body lengths travelled by walking and swimming migrants should be approximately invariant of body size. Data from over 200 species of migratory birds, mammals, fish, and invertebrates support the central conclusion of the model - that body size drives variation in maximum migration distance among species through its effects on metabolism and the cost of locomotion. The model provides a new tool to enhance general understanding of the ecology and evolution of migration. © 2011 Blackwell Publishing Ltd/CNRS.

  5. Developing an automated risk management tool to minimize bird and bat mortality at wind facilities.

    Science.gov (United States)

    Robinson Willmott, Julia; Forcey, Greg M; Hooton, Lauren A

    2015-11-01

    A scarcity of baseline data is a significant barrier to understanding and mitigating potential impacts of offshore development on birds and bats. Difficult and sometimes unpredictable conditions coupled with high expense make gathering such data a challenge. The Acoustic and Thermographic Offshore Monitoring (ATOM) system combines thermal imaging with acoustic and ultrasound sensors to continuously monitor bird and bat abundance, flight height, direction, and speed. ATOM's development and potential capabilities are discussed, and illustrated using onshore and offshore test data obtained over 16 months in the eastern USA. Offshore deployment demonstrated birds tending to fly into winds and activity declining sharply in winds >10 km h(-1). Passerines showed distinct seasonal changes in flight bearing and flew higher than non-passerines. ATOM data could be used to automatically shut down wind turbines to minimize collision mortality while simultaneously providing information for modeling activity in relation to weather and season.

  6. Fossilized melanosomes and the colour of Cretaceous dinosaurs and birds.

    Science.gov (United States)

    Zhang, Fucheng; Kearns, Stuart L; Orr, Patrick J; Benton, Michael J; Zhou, Zhonghe; Johnson, Diane; Xu, Xing; Wang, Xiaolin

    2010-02-25

    Spectacular fossils from the Early Cretaceous Jehol Group of northeastern China have greatly expanded our knowledge of the diversity and palaeobiology of dinosaurs and early birds, and contributed to our understanding of the origin of birds, of flight, and of feathers. Pennaceous (vaned) feathers and integumentary filaments are preserved in birds and non-avian theropod dinosaurs, but little is known of their microstructure. Here we report that melanosomes (colour-bearing organelles) are not only preserved in the pennaceous feathers of early birds, but also in an identical manner in integumentary filaments of non-avian dinosaurs, thus refuting recent claims that the filaments are partially decayed dermal collagen fibres. Examples of both eumelanosomes and phaeomelanosomes have been identified, and they are often preserved in life position within the structure of partially degraded feathers and filaments. Furthermore, the data here provide empirical evidence for reconstructing the colours and colour patterning of these extinct birds and theropod dinosaurs: for example, the dark-coloured stripes on the tail of the theropod dinosaur Sinosauropteryx can reasonably be inferred to have exhibited chestnut to reddish-brown tones.

  7. MIGRATORY GAME BIRDS AS A SOURCE OF PUBLIC EXPOSURE FROM THE FUKUSHIMA NUCLEAR POWER PLANT ACCIDENT

    Directory of Open Access Journals (Sweden)

    I. P. Stamat

    2011-01-01

    Full Text Available This article examines assessments of the impact of the Fukushima nuclear power plant accident on exposure of the Russian Federation population related to the seasonal migration of game birds. Intake of artificial radionuclides with meat of migratory game birds is shown to be one of the major pathways for the population exposure in the Far Eastern region of the country.

  8. Condition varies with habitat choice in postbreeding forest birds

    Science.gov (United States)

    Scott H. Stoleson

    2013-01-01

    Many birds that are experiencing population declines require extensive tracts of mature forest habitat for breeding. Recent work suggests that at least some may shift their habitat use to early-successional areas after nesting but before migration. I used constant-effort mist netting in regenerating clearcuts (4-8 years postcut) and dense mature-forest understories to...

  9. Bioaccumulation of uranium 234U and 238U in marine birds

    International Nuclear Information System (INIS)

    Borylo, A.; Skwarzec, B.

    2010-01-01

    In the paper was presented results of our study about uranium 234 U and 238 U radioactivity in the marine birds samples, collected in the Polish area of the southern Baltic Sea. We chose 11 species of sea birds: three species permanently residing at southern Baltic, four species of wintering birds and three species of migrating birds. The obtained results indicated that uranium is very irregularly distributed in organs and tissues of marine birds. The highest uranium content is characterized in liver, rest of viscera and feathers, the smallest in skin and muscles. The uranium concentration was higher for carnivorous species (long-tailed duck (C. hyemalis), common eider (S. mollissima), lower for species eating fish (great cormorant (P. carbo), common guillemot (U. aalge), red-throated diver (G. stellata) and razorbill (A. tarda)), but the biggest amounts for herbivorous species [tufted duck (A. fuligula) and eurasian coot (F. atra)]. About 63-67% of uranium, which was located in feathers of two species of marine birds: razorbill (A. tarda) and long-tailed duck (C. hymealis), was apparently adsorbed, which suggests that uranium adsorption on the feathers may be an important transfer from air to water. (author)

  10. Experience drives innovation of new migration patterns of whooping cranes in response to global change.

    Science.gov (United States)

    Teitelbaum, Claire S; Converse, Sarah J; Fagan, William F; Böhning-Gaese, Katrin; O'Hara, Robert B; Lacy, Anne E; Mueller, Thomas

    2016-09-06

    Anthropogenic changes in climate and land use are driving changes in migration patterns of birds worldwide. Spatial changes in migration have been related to long-term temperature trends, but the intrinsic mechanisms by which migratory species adapt to environmental change remain largely unexplored. We show that, for a long-lived social species, older birds with more experience are critical for innovating new migration behaviours. Groups containing older, more experienced individuals establish new overwintering sites closer to the breeding grounds, leading to a rapid population-level shift in migration patterns. Furthermore, these new overwintering sites are in areas where changes in climate have increased temperatures and where food availability from agriculture is high, creating favourable conditions for overwintering. Our results reveal that the age structure of populations is critical for the behavioural mechanisms that allow species to adapt to global change, particularly for long-lived animals, where changes in behaviour can occur faster than evolution.

  11. Experience drives innovation of new migration patterns of whooping cranes in response to global change

    Science.gov (United States)

    Teitelbaum, Claire S.; Converse, Sarah J.; Fagan, William F.; Böhning-Gaese, Katrin; O'Hara, Robert B.; Lacy, Anne E; Mueller, Thomas

    2016-01-01

    Anthropogenic changes in climate and land use are driving changes in migration patterns of birds worldwide. Spatial changes in migration have been related to long-term temperature trends, but the intrinsic mechanisms by which migratory species adapt to environmental change remain largely unexplored. We show that, for a long-lived social species, older birds with more experience are critical for innovating new migration behaviours. Groups containing older, more experienced individuals establish new overwintering sites closer to the breeding grounds, leading to a rapid population-level shift in migration patterns. Furthermore, these new overwintering sites are in areas where changes in climate have increased temperatures and where food availability from agriculture is high, creating favourable conditions for overwintering. Our results reveal that the age structure of populations is critical for the behavioural mechanisms that allow species to adapt to global change, particularly for long-lived animals, where changes in behaviour can occur faster than evolution.

  12. The NASA radar entomology program at Wallops Flight Center

    Science.gov (United States)

    Vaughn, C. R.

    1979-01-01

    NASA contribution to radar entomology is presented. Wallops Flight Center is described in terms of its radar systems. Radar tracking of birds and insects was recorded from helicopters for airspeed and vertical speed.

  13. Kinematic Optimization in Birds, Bats and Ornithopters

    Science.gov (United States)

    Reichert, Todd

    Birds and bats employ a variety of advanced wing motions in the efficient production of thrust. The purpose of this thesis is to quantify the benefit of these advanced wing motions, determine the optimal theoretical wing kinematics for a given flight condition, and to develop a methodology for applying the results in the optimal design of flapping-wing aircraft (ornithopters). To this end, a medium-fidelity, combined aero-structural model has been developed that is capable of simulating the advanced kinematics seen in bird flight, as well as the highly non-linear structural deformations typical of high-aspect ratio wings. Five unique methods of thrust production observed in natural species have been isolated, quantified and thoroughly investigated for their dependence on Reynolds number, airfoil selection, frequency, amplitude and relative phasing. A gradient-based optimization algorithm has been employed to determined the wing kinematics that result in the minimum required power for a generalized aircraft or species in any given flight condition. In addition to the theoretical work, with the help of an extended team, the methodology was applied to the design and construction of the world's first successful human-powered ornithopter. The Snowbird Human-Powered Ornithopter, is used as an example aircraft to show how additional design constraints can pose limits on the optimal kinematics. The results show significant trends that give insight into the kinematic operation of natural species. The general result is that additional complexity, whether it be larger twisting deformations or advanced wing-folding mechanisms, allows for the possibility of more efficient flight. At its theoretical optimum, the efficiency of flapping-wings exceeds that of current rotors and propellers, although these efficiencies are quite difficult to achieve in practice.

  14. Offshore wind turbines and bird activity at Blyth

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    In 1996, a study was implemented to ultimately determine the impact of two 2MW wind turbines situated 900 metres offshore of the north-east of England. The turbines, with a hub height of 66 metres, began operation in December 2000. Earlier, similar studies were carried out on a row of wind turbines mounted on the harbour wall of the nearby town of Blyth. The report gives details of (i) total mortality and mortality due to the turbines; (ii) number of bird strikes; (iii) habitat displacement; (iv) feeding grounds; (v) flight routes and (vi) impact on bird populations of a nearby Site of Special Scientific Interest. The study was conducted by AMEC Wind Limited under contract to the DTI.

  15. Differential sex- and age-related migration of Bluethroats Luscinia svecica at Eilat, Israel

    Science.gov (United States)

    Markovets, Mikhail L.; Zduniak, Piotr; Yosef, Reuven

    2008-07-01

    This paper examines the phenology and biometrics of Bluethroats staging in the Eilat region. This is of special interest because of the extreme conditions with which this temperate zone breeding species has to contend because Eilat is a desert habitat and is the last green area before the crossing of the deserts in autumn or after it in spring. Data were collected during 20 spring and 18 autumn migration seasons in the years 1984-2003, and a total of 7,464 Bluethroat were recorded. The number of trapped birds was much higher in autumn than in spring. The majority of Bluethroats caught in both the autumn and spring migrations were juveniles. We found differences in sex ratio in the individual age classes only in the autumn wherein among both adults and juveniles, males were in greater numbers. We also found significant differences in the dates of ringed birds from different sex-age classes in the spring and in autumn migrations. In spring, males from both age classes were caught earlier than females. In autumn, adult birds arrived earlier than juveniles. We think that it is important to identify and conserve the high quality stopover habitats such as Eilat wherein not only Bluethroats have been shown to stopover but also several hundred other species.

  16. Fine-scale flight strategies of gulls in urban airflows indicate risk and reward in city living.

    Science.gov (United States)

    Shepard, Emily L C; Williamson, Cara; Windsor, Shane P

    2016-09-26

    Birds modulate their flight paths in relation to regional and global airflows in order to reduce their travel costs. Birds should also respond to fine-scale airflows, although the incidence and value of this remains largely unknown. We resolved the three-dimensional trajectories of gulls flying along a built-up coastline, and used computational fluid dynamic models to examine how gulls reacted to airflows around buildings. Birds systematically altered their flight trajectories with wind conditions to exploit updraughts over features as small as a row of low-rise buildings. This provides the first evidence that human activities can change patterns of space-use in flying birds by altering the profitability of the airscape. At finer scales still, gulls varied their position to select a narrow range of updraught values, rather than exploiting the strongest updraughts available, and their precise positions were consistent with a strategy to increase their velocity control in gusty conditions. Ultimately, strategies such as these could help unmanned aerial vehicles negotiate complex airflows. Overall, airflows around fine-scale features have profound implications for flight control and energy use, and consideration of this could lead to a paradigm-shift in the way ecologists view the urban environment.This article is part of the themed issue 'Moving in a moving medium: new perspectives on flight'. © 2016 The Author(s).

  17. Stopover habitats of spring migrating surf scoters in southeast Alaska

    Science.gov (United States)

    Lok, E.K.; Esler, Daniel; Takekawa, John Y.; De La Cruz, S.W.; Sean, Boyd W.; Nysewander, D.R.; Evenson, J.R.; Ward, D.H.

    2011-01-01

    Habitat conditions and nutrient reserve levels during spring migration have been suggested as important factors affecting population declines in waterfowl, emphasizing the need to identify key sites used during spring and understand habitat features and resource availability at stopover sites. We used satellite telemetry to identify stopover sites used by surf scoters migrating through southeast Alaska during spring. We then contrasted habitat features of these sites to those of random sites to determine habitat attributes corresponding to use by migrating scoters. We identified 14 stopover sites based on use by satellite tagged surf scoters from several wintering sites. We identified Lynn Canal as a particularly important stopover site for surf scoters originating throughout the Pacific winter range; approximately half of tagged coastally migrating surf scoters used this site, many for extended periods. Stopover sites were farther from the mainland coast and closer to herring spawn sites than random sites, whereas physical shoreline habitat attributes were generally poor predictors of site use. The geography and resource availability within southeast Alaska provides unique and potentially critical stopover habitat for spring migrating surf scoters. Our work identifies specific sites and habitat resources that deserve conservation and management consideration. Aggregations of birds are vulnerable to human activity impacts such as contaminant spills and resource management decisions. This information is of value to agencies and organizations responsible for emergency response planning, herring fisheries management, and bird and ecosystem conservation. Copyright ?? 2011 The Wildlife Society.

  18. Southward autumn migration of waterfowl facilitates cross-continental transmission of the highly pathogenic avian influenza H5N1 virus

    NARCIS (Netherlands)

    Xu, Yanjie; Gong, Peng; Wielstra, Ben; Si, Yali

    2016-01-01

    The highly pathogenic avian influenza subtype H5N1 (HPAI H5N1) is a worldwide zoonotic infectious disease, threatening humans, poultry and wild birds. The role of wild birds in the spread of HPAI H5N1 has previously been investigated by comparing disease spread patterns with bird migration

  19. An annotated checklist of pathogenic microorganisms associated with migratory birds

    Czech Academy of Sciences Publication Activity Database

    Hubálek, Zdeněk

    2004-01-01

    Roč. 40, č. 4 (2004), s. 639-659 ISSN 0090-3558 R&D Projects: GA ČR GA206/03/0726 Institutional research plan: CEZ:AV0Z6093917 Keywords : Arboviruses * birds * migration Subject RIV: EE - Microbiology, Virology Impact factor: 0.741, year: 2004 http://www.jwildlifedis.org/cgi/reprint/40/4/639

  20. Computational modeling of aerodynamics in the fast forward flight of hummingbirds

    Science.gov (United States)

    Song, Jialei; Luo, Haoxiang; Tobalske, Bret; Hedrick, Tyson

    2015-11-01

    Computational models of the hummingbird at flight speed 8.3 m/s is built based on high-speed imaging of the real bird flight in the wind tunnel. The goal is to understand the lift and thrust production of the wings at the high advance ratio (flight speed to the average wingtip speed) around 1. Both the full 3D CFD model based on an immersed-boundary method and the blade-element model based on quasi-steady flow assumption were adopted to analyze the aerodynamics. The result shows that while the weight support is generated during downstroke, little negative weight support is produced during upstroke. On the other hand, thrust is generated during both downstroke and upstroke, which allows the bird to overcome drag induced at fast flight. The lift and thrust characteristics are closely related to the instantaneous wing position and motion. In addition, the flow visualization shows that the leading-edge vortex is stable during most of the wing-beat, which may have contributed to the lift and thrust enhancement. NSF CBET-0954381.

  1. Alabama ESI: BIRDS (Bird Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for wading birds, shorebirds, waterfowl, raptors, diving birds, seabirds, passerine birds, gulls, and terns...

  2. Maryland ESI: BIRDS (Bird Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for wading birds, shorebirds, waterfowl, raptors, diving birds, seabirds, passerine birds, and gulls and...

  3. Magnetic information affects the stellar orientation of young bird migrants

    Science.gov (United States)

    Weindler, Peter; Wiltschko, Roswitha; Wiltschko, Wolfgang

    1996-09-01

    WHEN young birds leave on their first migration, they are guided by innate information about their direction of migration. It is generally assumed that this direction is represented twice, namely with respect to celestial rotation and with respect to the Earth's magnetic field1,2. The interactions between the two cue systems have been analysed by exposing hand-raised young birds during the premigratory period to cue-conflict situations, in which celestial rotation and the magnetic field provided different information. Celestial rotation altered the course with respect to the magnetic field3-7, whereas conflicting magnetic information did not seem to affect the course with respect to the stars8,9. Celestial information thus seemed to dominate over magnetic information. Here we report that the interaction between the two cue systems is far more complex than this. Celestial rotation alone seems to provide only a tendency to move away from its centre (towards geographical south), which is then modified by information from the magnetic field to establish the distinctive, population-specific migratory direction.

  4. Using wind tunnels to predict bird mortality in wind farms: the case of griffon vultures.

    Science.gov (United States)

    de Lucas, Manuela; Ferrer, Miguel; Janss, Guyonne F E

    2012-01-01

    Wind farms have shown a spectacular growth during the last 15 years. Avian mortality through collision with moving rotor blades is well-known as one of the main adverse impacts of wind farms. In Spain, the griffon vulture incurs the highest mortality rates in wind farms. As far as we know, this study is the first attempt to predict flight trajectories of birds in order to foresee potentially dangerous areas for wind farm development. We analyse topography and wind flows in relation to flight paths of griffon vultures, using a scaled model of the wind farm area in an aerodynamic wind tunnel, and test the difference between the observed flight paths of griffon vultures and the predominant wind flows. Different wind currents for each wind direction in the aerodynamic model were observed. Simulations of wind flows in a wind tunnel were compared with observed flight paths of griffon vultures. No statistical differences were detected between the observed flight trajectories of griffon vultures and the wind passages observed in our wind tunnel model. A significant correlation was found between dead vultures predicted proportion of vultures crossing those cells according to the aerodynamic model. Griffon vulture flight routes matched the predominant wind flows in the area (i.e. they followed the routes where less flight effort was needed). We suggest using these kinds of simulations to predict flight paths over complex terrains can inform the location of wind turbines and thereby reduce soaring bird mortality.

  5. Transmission of influenza reflects seasonality of wild birds across the annual cycle

    Science.gov (United States)

    Hill, Nichola J.; Ma, Eric J.; Meixell, Brandt W.; Lindberg, Mark S.; Boyce, Walter M.; Runstadler, Jonathan A.

    2016-01-01

    Influenza A Viruses (IAV) in nature must overcome shifting transmission barriers caused by the mobility of their primary host, migratory wild birds, that change throughout the annual cycle. Using a phylogenetic network of viral sequences from North American wild birds (2008–2011) we demonstrate a shift from intraspecific to interspecific transmission that along with reassortment, allows IAV to achieve viral flow across successive seasons from summer to winter. Our study supports amplification of IAV during summer breeding seeded by overwintering virus persisting locally and virus introduced from a wide range of latitudes. As birds migrate from breeding sites to lower latitudes, they become involved in transmission networks with greater connectivity to other bird species, with interspecies transmission of reassortant viruses peaking during the winter. We propose that switching transmission dynamics may be a critical strategy for pathogens that infect mobile hosts inhabiting regions with strong seasonality.

  6. Selection of passerine birds as bio-sentinel of persistent organic pollutants in terrestrial environment.

    Science.gov (United States)

    Mo, Ling; Zheng, Xiaobo; Sun, Yuxin; Yu, Lehuan; Luo, Xiaojun; Xu, Xiangrong; Qin, Xiaoquan; Gao, Yongli; Mai, Bixian

    2018-08-15

    A broad suite of persistent organic pollutants (POPs), including polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and dichlorodiphenyltrichloroethane (DDT) and its metabolites, were analyzed in pectoral muscle of eight terrestrial passerine bird species from an extensive e-waste recycling site in South China. Concentrations of PCBs, PBDEs, and DDTs in bird samples ranged from 1260-279,000, 121-14,200, and 31-7910ng/g lipid weight, respectively. Insectivorous birds had significantly higher levels of PCBs, PBDEs, and DDTs than those in granivorous birds. Concentrations of POPs in resident insectivorous birds were significantly greater than those in migrant insectivorous birds. PCBs were the predominant pollutants in all bird species from the e-waste site, followed by PBDEs and DDTs, indicating that PCBs were mainly derived from e-wastes. The granivorous birds had higher proportions of hepta-CBs in total PCBs and higher proportions of octa- to deca-BDEs in total PBDEs compared with the insectivorous birds. The various dietary sources, migration behavior, and possible biotransformation were suspected as reasons of the distinct profiles of POPs in different bird species. The δ 15 N values were significantly and positively correlated with concentrations of POPs in resident insectivorous birds, but not in other passerine bird species, suggesting the influence of trophic levels on bioaccumulation of POPs in resident insectivorous birds. The resident insectivorous birds seem to be promising bio-sentinel of POPs in terrestrial environment around the e-waste sites. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Patterns of migrating soaring migrants indicate attraction to marine wind farms.

    Science.gov (United States)

    Skov, Henrik; Desholm, Mark; Heinänen, Stefan; Kahlert, Johnny A; Laubek, Bjarke; Jensen, Niels Einar; Žydelis, Ramūnas; Jensen, Bo Præstegaard

    2016-12-01

    Monitoring of bird migration at marine wind farms has a short history, and unsurprisingly most studies have focused on the potential for collisions. Risk for population impacts may exist to soaring migrants such as raptors with K-strategic life-history characteristics. Soaring migrants display strong dependence on thermals and updrafts and an affinity to land areas and islands during their migration, a behaviour that creates corridors where raptors move across narrow straits and sounds and are attracted to islands. Several migration corridors for soaring birds overlap with the development regions for marine wind farms in NW Europe. However, no empirical data have yet been available on avoidance or attraction rates and behavioural reactions of soaring migrants to marine wind farms. Based on a post-construction monitoring study, we show that all raptor species displayed a significant attraction behaviour towards a wind farm. The modified migratory behaviour was also significantly different from the behaviour at nearby reference sites. The attraction was inversely related to distance to the wind farm and was primarily recorded during periods of adverse wind conditions. The attraction behaviour suggests that migrating raptor species are far more at risk of colliding with wind turbines at sea than hitherto assessed. © 2016 The Author(s).

  8. DYNAMIC TUNING OF INSECT AND BIRD WINGS AND COPEPOD AND DAPHNIA APPENDAGES

    Science.gov (United States)

    Compressible flow theory suggests, and dimensional analysis and growing empirical evidence confirm that, to aid flight, many insects and even some birds, notably hummingbirds, tune their wing-beat frequency to a corresponding characteristic harmonic frequency of air. The same pro...

  9. Juvenile Osprey Navigation during Trans-Oceanic Migration.

    Directory of Open Access Journals (Sweden)

    Travis W Horton

    Full Text Available To compensate for drift, an animal migrating through air or sea must be able to navigate. Although some species of bird, fish, insect, mammal, and reptile are capable of drift compensation, our understanding of the spatial reference frame, and associated coordinate space, in which these navigational behaviors occur remains limited. Using high resolution satellite-monitored GPS track data, we show that juvenile ospreys (Pandion haliaetus are capable of non-stop constant course movements over open ocean spanning distances in excess of 1500 km despite the perturbing effects of winds and the lack of obvious landmarks. These results are best explained by extreme navigational precision in an exogenous spatio-temporal reference frame, such as positional orientation relative to Earth's magnetic field and pacing relative to an exogenous mechanism of keeping time. Given the age (<1 year-old of these birds and knowledge of their hatching site locations, we were able to transform Enhanced Magnetic Model coordinate locations such that the origin of the magnetic coordinate space corresponded with each bird's nest. Our analyses show that trans-oceanic juvenile osprey movements are consistent with bicoordinate positional orientation in transformed magnetic coordinate or geographic space. Through integration of movement and meteorological data, we propose a new theoretical framework, chord and clock navigation, capable of explaining the precise spatial orientation and temporal pacing performed by juvenile ospreys during their long-distance migrations over open ocean.

  10. Effects of wind turbines on birds. What needs to be taken into account in Finland

    International Nuclear Information System (INIS)

    Walsh, M.

    1997-01-01

    The author examines the current knowledge on bird fatalities from wind turbines. As the number of turbines around the Finnish coast increases, concern has been voiced by some ornithologists for the safety of birds, particularly during migration. However, studies confirm that few birds collide with wind turbines during the day, with the exception of some large birds of prey that sometimes attempt to use the tower or blades for perching. At night the collision risk is somewhat higher, but average collision rates per kilometre of wind turbines placed in a row (including the space between individual machines) is no higher than that per kilometre of motorway, an acceptable figure in view of the relatively low numbers of machines compared to roads. Wind turbines can potentially do more serious damage to birds if they are erected too near large breeding concentrations, e.g. important coastal wetlands. Many groups of water and wading birds avoid feeding or nesting near turbines up to a range of 500-700 metres. (orig.)

  11. Wind conditions and geography shape the first outbound migration of juvenile honey buzzards and their distribution across sub-Saharan Africa.

    Science.gov (United States)

    Vansteelant, W M G; Kekkonen, J; Byholm, P

    2017-05-31

    Contemporary tracking studies reveal that low migratory connectivity between breeding and non-breeding ranges is common in migrant landbirds. It is unclear, however, how internal factors and early-life experiences of individual migrants shape the development of their migration routes and concomitant population-level non-breeding distributions. Stochastic wind conditions and geography may determine whether and where migrants end up by the end of their journey. We tested this hypothesis by satellite-tagging 31 fledgling honey buzzards Pernis apivorus from southern Finland and used a global atmospheric reanalysis model to estimate the wind conditions they encountered on their first outbound migration. Migration routes diverged rapidly upon departure and the birds eventually spread out across 3340 km of longitude. Using linear regression models, we show that the birds' longitudinal speeds were strongly affected by zonal wind speed, and negatively affected by latitudinal wind, with significant but minor differences between individuals. Eventually, 49% of variability in the birds' total longitudinal displacements was accounted for by wind conditions on migration. Some birds circumvented the Baltic Sea via Scandinavia or engaged in unusual downwind movements over the Mediterranean, which also affected the longitude at which these individuals arrived in sub-Saharan Africa. To understand why adult migrants use the migration routes and non-breeding sites they use, we must take into account the way in which wind conditions moulded their very first journeys. Our results present some of the first evidence into the mechanisms through which low migratory connectivity emerges. © 2017 The Authors.

  12. Wind conditions and geography shape the first outbound migration of juvenile honey buzzards and their distribution across sub-Saharan Africa

    Science.gov (United States)

    Kekkonen, J.; Byholm, P.

    2017-01-01

    Contemporary tracking studies reveal that low migratory connectivity between breeding and non-breeding ranges is common in migrant landbirds. It is unclear, however, how internal factors and early-life experiences of individual migrants shape the development of their migration routes and concomitant population-level non-breeding distributions. Stochastic wind conditions and geography may determine whether and where migrants end up by the end of their journey. We tested this hypothesis by satellite-tagging 31 fledgling honey buzzards Pernis apivorus from southern Finland and used a global atmospheric reanalysis model to estimate the wind conditions they encountered on their first outbound migration. Migration routes diverged rapidly upon departure and the birds eventually spread out across 3340 km of longitude. Using linear regression models, we show that the birds' longitudinal speeds were strongly affected by zonal wind speed, and negatively affected by latitudinal wind, with significant but minor differences between individuals. Eventually, 49% of variability in the birds' total longitudinal displacements was accounted for by wind conditions on migration. Some birds circumvented the Baltic Sea via Scandinavia or engaged in unusual downwind movements over the Mediterranean, which also affected the longitude at which these individuals arrived in sub-Saharan Africa. To understand why adult migrants use the migration routes and non-breeding sites they use, we must take into account the way in which wind conditions moulded their very first journeys. Our results present some of the first evidence into the mechanisms through which low migratory connectivity emerges. PMID:28539514

  13. Transport of Ixodid ticks and tick-borne pathogens by migratory birds.

    Directory of Open Access Journals (Sweden)

    Gunnar eHasle

    2013-09-01

    Full Text Available Birds, particularly passerines, can be parasitized by Ixodid ticks, which may be infected with tick-borne pathogens, like Borrelia spp., Babesia spp., Anaplasma, Rickettsia/Coxiella, and tick-borne encephalitis virus. The prevalence of ticks on birds varies over years, season, locality and different bird species. The prevalence of ticks on different species depends mainly on the degree of feeding on the ground. In Europe, the Turdus spp., especially the blackbird, Turdus merula, appears to be most important for harboring ticks. Birds can easily cross barriers, like fences, mountains, glaciers, desserts and oceans, which would stop mammals, and they can move much faster than the wingless hosts. Birds can potentially transport tick-borne pathogens by transporting infected ticks, by being infected with tick-borne pathogens and transmit the pathogens to the ticks, and possibly act as hosts for transfer of pathogens between ticks through co-feeding. Knowledge of the bird migration routes and of the spatial distribution of tick species and tick-borne pathogens is crucial for understanding the possible impact of birds as spreaders of ticks and tick-borne pathogens. Successful colonization of new tick species or introduction of new tick-borne pathogens will depend on suitable climate, vegetation and hosts. Although it has never been demonstrated that a new tick species, or a new tick pathogen, actually has been established in a new locality after being seeded there by birds, evidence strongly suggests that this could occur.

  14. Information needs and priorities for assessing the sensitivity of marine birds to oil spills

    Energy Technology Data Exchange (ETDEWEB)

    Wiens, J.A.; Ford, G.; Heinemann, D.

    1984-01-01

    Experience in developing models to predict the potential impacts of oil spills on colonially breeding marine birds has revealed some major gaps in the information available on these systems. The authors consider the availability of data for a variety of parameters of seabird biology that are required in modelling efforts, and assign provisional priorities to the information needs. In order to develop means of predicting the impacts of oil spills on seabirds, the authors suggest that colony- or site-specific information on the timing of reproduction and colony occupancy, chick growth rates and body weights, several metabolic parameters, flight speed, and food load size is of relatively low overall priority. Intermediate priority is assigned to the collection of specific data on the dynamics of oil spills, the age and breeding structure of the populations, reproductive success, foraging activity budgets and flight paths, flight costs, and the response of growing chicks to food deprivation. The authors suggest that studies of seabird biology should give highest priority to obtaining information of population sizes, the probability of adult death upon encountering a spill, age-specific fecundity and survivorship, the time required in foraging trips, the lag time in the response of birds to an oil spill, foraging rate as a function of resource density, and changes in the availability of resources to the birds as a consequence of oil spills.

  15. Communally Nesting Migratory Birds Create Ecological Hot-Spots in Tropical Australia.

    Directory of Open Access Journals (Sweden)

    Daniel J D Natusch

    Full Text Available Large numbers of metallic starlings (Aplonis metallica migrate annually from New Guinea to the rainforests of tropical Australia, where they nest communally in single emergent trees (up to 1,000 birds. These aggregations create dense and species-rich faunal "hot-spots", attracting a diverse assemblage of local consumers that utilise this seasonal resource. The starlings nested primarily in poison-dart trees (Antiaris toxicaria near the rainforest-woodland boundary. Surveys underneath these colonies revealed that bird-derived nutrients massively increased densities of soil invertebrates and mammals (primarily wild pigs beneath trees, year-round. Flying invertebrates, nocturnal birds, reptiles, and amphibians congregated beneath the trees when starlings were nesting (the wet-season. Diurnal birds (primarily cockatoos and bush turkeys aggregated beneath the trees during the dry-season to utilise residual nutrients when the starlings were not nesting. The abundance of several taxa was considerably higher (to > 1000-fold under colony trees than under nearby trees. The system strikingly resembles utilisation of bird nesting colonies by predators in other parts of the world but this spectacular system has never been described, emphasizing the continuing need for detailed natural-history studies in tropical Australia.

  16. Communally Nesting Migratory Birds Create Ecological Hot-Spots in Tropical Australia.

    Science.gov (United States)

    Natusch, Daniel J D; Lyons, Jessica A; Brown, Gregory; Shine, Richard

    2016-01-01

    Large numbers of metallic starlings (Aplonis metallica) migrate annually from New Guinea to the rainforests of tropical Australia, where they nest communally in single emergent trees (up to 1,000 birds). These aggregations create dense and species-rich faunal "hot-spots", attracting a diverse assemblage of local consumers that utilise this seasonal resource. The starlings nested primarily in poison-dart trees (Antiaris toxicaria) near the rainforest-woodland boundary. Surveys underneath these colonies revealed that bird-derived nutrients massively increased densities of soil invertebrates and mammals (primarily wild pigs) beneath trees, year-round. Flying invertebrates, nocturnal birds, reptiles, and amphibians congregated beneath the trees when starlings were nesting (the wet-season). Diurnal birds (primarily cockatoos and bush turkeys) aggregated beneath the trees during the dry-season to utilise residual nutrients when the starlings were not nesting. The abundance of several taxa was considerably higher (to > 1000-fold) under colony trees than under nearby trees. The system strikingly resembles utilisation of bird nesting colonies by predators in other parts of the world but this spectacular system has never been described, emphasizing the continuing need for detailed natural-history studies in tropical Australia.

  17. First insights into the migration route and migratory connectivity of the Paddyfield Warbler using geolocator tagging and stable isotope analysis

    Czech Academy of Sciences Publication Activity Database

    Brlík, Vojtěch; Ilieva, M.; Lisovski, S.; Voigt, C. C.; Procházka, Petr

    (2018) ISSN 0021-8375 R&D Projects: GA ČR GA13-06451S Institutional support: RVO:68081766 Keywords : Bird migration * Indo-European flyway * Light-level geolocation * Migration direction Impact factor: 1.468, year: 2016

  18. Linking the evolution of body shape and locomotor biomechanics in bird-line archosaurs.

    Science.gov (United States)

    Allen, Vivian; Bates, Karl T; Li, Zhiheng; Hutchinson, John R

    2013-05-02

    Locomotion in living birds (Neornithes) has two remarkable features: feather-assisted flight, and the use of unusually crouched hindlimbs for bipedal support and movement. When and how these defining functional traits evolved remains controversial. However, the advent of computer modelling approaches and the discoveries of exceptionally preserved key specimens now make it possible to use quantitative data on whole-body morphology to address the biomechanics underlying this issue. Here we use digital body reconstructions to quantify evolutionary trends in locomotor biomechanics (whole-body proportions and centre-of-mass position) across the clade Archosauria. We use three-dimensional digital reconstruction to estimate body shape from skeletal dimensions for 17 archosaurs along the ancestral bird line, including the exceptionally preserved, feathered taxa Microraptor, Archaeopteryx, Pengornis and Yixianornis, which represent key stages in the evolution of the avian body plan. Rather than a discrete transition from more-upright postures in the basal-most birds (Avialae) and their immediate outgroup deinonychosauria, our results support hypotheses of a gradual, stepwise acquisition of more-crouched limb postures across much of theropod evolution, although we find evidence of an accelerated change within the clade Maniraptora (birds and their closest relatives, such as deinonychosaurs). In addition, whereas reduction of the tail is widely accepted to be the primary morphological factor correlated with centre-of-mass position and, hence, evolution of hindlimb posture, we instead find that enlargement of the pectoral limb and several associated trends have a much stronger influence. Intriguingly, our support for the onset of accelerated morpho-functional trends within Maniraptora is closely correlated with the evolution of flight. Because we find that the evolution of enlarged forelimbs is strongly linked, via whole-body centre of mass, to hindlimb function during

  19. Changes in timing of autumn migration in North European songbird populations

    DEFF Research Database (Denmark)

    Tøttrup, Anders Peter; Thorup, Kasper; Rahbek, Carsten

    2006-01-01

    Although studies of changes in the timing of passerine spring migration are numerous, less is known about timing of their autumn departure. We present phenological data on 22 species based on mist-netted birds caught on the Baltic island of Christiansø during autumn migration between 1976 and 1997...... departure (-0.0426 days year-1, P = 0.40). Testing the 12 species for which the entire migration period was included (thus excluding many long-distance migrants), we found an overall earlier departure (-0.18 days year-1, P = 0.007). Short-distance migrants tended to show earlier departure, while long...

  20. Fall migration routes, timing, and wintering sites of North American ospreys as determined by satellite telemetry

    Science.gov (United States)

    Martell, M.S.; Henny, Charles J.; Nye, P.; Solensky, Matthew J.

    2001-01-01

    Satellite telemetry was used to determine fall migratory movements of Ospreys (Pandion haliaetus) breeding in the United States. Study areas were established along the lower Columbia River between Oregon and Washington; in north-central Minnesota; on Shelter Island, New York; and in southern New Jersey. Seventy-four adults (25 males, 49 females) were tracked from 1995 through 1999. Migration routes differed among populations but not by sex. Western Ospreys migrated through California and to a lesser degree other western states and wintered in Mexico (88%), El Salvador (6%), and Honduras (6%) (25.9A?N to 13.0A?N and 108.3A?W to 87.3A?W). Minnesota Ospreys migrated along three routes: (1) through the Central U.S. and then along the east coast of Mexico, (2) along the Mississippi River Valley, then across the Gulf of Mexico, or (3) through the southeastern U.S., then across the Caribbean. East Coast birds migrated along the eastern seaboard of the U.S., through Florida, and across the Caribbean. Midwestern birds wintered from Mexico south to Bolivia (22.35A?N to 13.64A?S, and 91.75A?W to 61.76A?W), while East Coast birds wintered from Florida to as far south as Brazil (27.48A?N to 18.5A?S and 80.4A?W to 57.29A?W). Dates of departure from breeding areas differed significantly between sexes and geographic regions, with females leaving earlier than males. Western birds traveled a shorter distance than either midwestern or eastern Ospreys. Females traveled farther than males from the same population, which resulted in females typically wintering south of males.

  1. Birds of passage no more: migration decision making among Filipino immigrants in Hawaii.

    Science.gov (United States)

    Arnold, F

    1987-03-01

    Using data primarily from the Honolulu Destination Survey (HDS), which is part of the Philippine Migration Study (a study of a migration system that has its origins in Ilocos Norte, a largely rural province in the Philippines), the author examines migration decision making among Philippine immigrants in Hawaii. The HDS, conducted in 1981, interviewed 1484 residents of Honolulu who immigrated from the Ilocos Region after the US immigration law was liberalized in 1965. Results from the Philippine Migration Study (PMS) survey show that of those who did not have any intentions to move within 2 years in 1980, 88% did not move between 1980 and 1982. Of those who said they were certain to move within 2 years, 54% actually moved, while only 36% who were fairly certain and 31% who were uncertain moved. Virtually all of those who actually moved to Hawaii from 1980-1982 had intended to move to Hawaii in 1980. It thus appears that most migration is planned well in advance. For those who have already migrated, their behavior in the destination is influenced by their expectations about future migration. An estimated 20-38.7% of legal immigrants to the US from the Philippines in 1971 had emigrated as of January 1979. 49% of HDS respondents said that they did not intend to move out of Hawaii any time in the future. Among those who intend to move in the future, 69% want to return to Ilocos and 26% intend to move to the US mainland. 40% want to leave Hawaii for economic reasons and 27% for affiliation purposes. The value expectancy framework used in the PMS measures expectations of achieving one's most important goals in alternative locations. The analysis employs both binomial and multinomial logit analysis to identify significant determinants of future migration intentions. The 7 conceptual categories are: wealth, status, comfort, stimulation, autonomy, affiliation, and morality. 90% consider "having a peaceful life" followed by "getting ahead in the world" the most important

  2. Abdominally implanted satellite transmitters affect reproduction and survival rather than migration of large shorebirds

    Science.gov (United States)

    Hooijmeijer, Jos C. E. W.; Gill, Robert E.; Mulcahy, Daniel M.; Tibbitts, T. Lee; Kentie, Rosemarie; Gerritsen, Gerrit J.; Bruinzeel, Leo W.; Tijssen, David C.; Harwood, Christopher M.; Piersma, Theunis

    2014-01-01

    Satellite telemetry has become a common technique to investigate avian life-histories, but whether such tagging will affect fitness is a critical unknown. In this study, we evaluate multi-year effects of implanted transmitters on migratory timing and reproductive performance in shorebirds. Shorebirds increasingly are recognized as good models in ecology and evolution. That many of them are of conservation concern adds to the research responsibilities. In May 2009, we captured 56 female Black-tailed Godwits Limosa limosa limosa during late incubation in The Netherlands. Of these, 15 birds were equipped with 26-g satellite transmitters with a percutaneous antenna (7.8 % ± 0.2 SD of body mass), surgically implanted in the coelom. We compared immediate nest survival, timing of migration, subsequent nest site fidelity and reproductive behaviour including egg laying with those of the remaining birds, a comparison group of 41 females. We found no effects on immediate nest survival. Fledging success and subsequent southward and northward migration patterns of the implanted birds conformed to the expectations, and arrival time on the breeding grounds in 2010–2012 did not differ from the comparison group. Compared with the comparison group, in the year after implantation, implanted birds were equally faithful to the nest site and showed equal territorial behaviour, but a paucity of behaviours indicating nests or clutches. In the 3 years after implantation, the yearly apparent survival of implanted birds was 16 % points lower. Despite intense searching, we found only three eggs of two implanted birds; all were deformed. A similarly deformed egg was reported in a similarly implanted Whimbrel Numenius phaeopus returning to breed in central Alaska. The presence in the body cavity of an object slightly smaller than a normal egg may thus lead to egg malformation and, likely, reduced egg viability. That the use of implanted satellite transmitters in these large shorebirds

  3. Spotted fever Rickettsia species in Hyalomma and Ixodes ticks infesting migratory birds in the European Mediterranean area

    Science.gov (United States)

    2014-01-01

    Background A few billion birds migrate annually between their breeding grounds in Europe and their wintering grounds in Africa. Many bird species are tick-infested, and as a result of their innate migratory behavior, they contribute significantly to the geographic distribution of pathogens, including spotted fever rickettsiae. The aim of the present study was to characterize, in samples from two consecutive years, the potential role of migrant birds captured in Europe as disseminators of Rickettsia-infected ticks. Methods Ticks were collected from a total of 14,789 birds during their seasonal migration northwards in spring 2009 and 2010 at bird observatories on two Mediterranean islands: Capri and Antikythira. All ticks were subjected to RNA extraction followed by cDNA synthesis and individually assayed with a real-time PCR targeting the citrate synthase (gltA) gene. For species identification of Rickettsia, multiple genes were sequenced. Results Three hundred and ninety-eight (2.7%) of all captured birds were tick-infested; some birds carried more than one tick. A total number of 734 ticks were analysed of which 353 ± 1 (48%) were Rickettsia-positive; 96% were infected with Rickettsia aeschlimannii and 4% with Rickettsia africae or unidentified Rickettsia species. The predominant tick taxon, Hyalomma marginatum sensu lato constituted 90% (n = 658) of the ticks collected. The remaining ticks were Ixodes frontalis, Amblyomma sp., Haemaphysalis sp., Rhipicephalus sp. and unidentified ixodids. Most ticks were nymphs (66%) followed by larvae (27%) and adult female ticks (0.5%). The majority (65%) of ticks was engorged and nearly all ticks contained visible blood. Conclusions Migratory birds appear to have a great impact on the dissemination of Rickettsia-infected ticks, some of which may originate from distant locations. The potential ecological, medical and veterinary implications of such Rickettsia infections need further examination. PMID:25011617

  4. Migration ecology and stopover population size of Red Knots Calidris canutus rufa at Mingan Archipelago after exiting the breeding grounds

    Science.gov (United States)

    Lyons, James E.; Baker, Allan J.; González, Patricia M.; Aubry, Yves; Buidin, Christophe; Rochepault, Yann

    2018-01-01

    Populations of migratory birds present unique conservation challenges given the often vast distances separating critical resources throughout the annual cycle. Migration areas close to the breeding grounds represent a link between two key stages of the annual cycle, and understanding migration ecology as birds exit the breeding grounds may be particularly informative for successful conservation. We studied migration phenology and stopover ecology of an endangered subspecies of the Red Knot Calidris canutus rufa at a migration area relatively close to its breeding range. Using mark-recapture/resight data and a Jolly-Seber model for open populations, we described the arrival and departure schedules, stopover duration, and passage population size at the Mingan Archipelago, Quebec, Canada. Red Knots arrived at the study area in two distinct waves of birds separated by approximately 22 days. Nearly 30% of the passage population arrived in the first wave of arrivals during 15–18 July, and approximately 22% arrived in a second wave during 8–11 August. The sex-ratio in the stopover population at the time of the first wave was slightly skewed toward females, whereas the second wave was heavily skewed toward males. Because males remain on the breeding grounds to care for young, this may reflect successfulbreeding in the year of our study. The estimated stopover duration (population mean) was 11 days (95% credible interval: 10.3–11.7 days), but stopover persistence was variable throughout the season. We estimated a passage population size of 9,450 birds (8,355–10,710), a minimum estimate for reasons related to the duration of our sampling. Mingan Archipelago is thus an important migration area for this endangered subspecies and could be a priority in conservation planning. Our results also emphasize the advantages of mark-recapture/resight approaches for estimating migration phenology and stopover persistence.

  5. Eco-Virological Approach for Assessing the Role of Wild Birds in the Spread of Avian Influenza H5N1 along the Central Asian Flyway

    Science.gov (United States)

    Newman, Scott H.; Hill, Nichola J.; Spragens, Kyle A.; Janies, Daniel; Voronkin, Igor O.; Prosser, Diann J.; Yan, Baoping; Lei, Fumin; Batbayar, Nyambayar; Natsagdorj, Tseveenmyadag; Bishop, Charles M.; Butler, Patrick J.; Wikelski, Martin; Balachandran, Sivananinthaperumal; Mundkur, Taej; Douglas, David C.; Takekawa, John Y.

    2012-01-01

    A unique pattern of highly pathogenic avian influenza (HPAI) H5N1 outbreaks has emerged along the Central Asia Flyway, where infection of wild birds has been reported with steady frequency since 2005. We assessed the potential for two hosts of HPAI H5N1, the bar-headed goose (Anser indicus) and ruddy shelduck (Tadorna tadorna), to act as agents for virus dispersal along this ‘thoroughfare’. We used an eco-virological approach to compare the migration of 141 birds marked with GPS satellite transmitters during 2005–2010 with: 1) the spatio-temporal patterns of poultry and wild bird outbreaks of HPAI H5N1, and 2) the trajectory of the virus in the outbreak region based on phylogeographic mapping. We found that biweekly utilization distributions (UDs) for 19.2% of bar-headed geese and 46.2% of ruddy shelduck were significantly associated with outbreaks. Ruddy shelduck showed highest correlation with poultry outbreaks owing to their wintering distribution in South Asia, where there is considerable opportunity for HPAI H5N1 spillover from poultry. Both species showed correlation with wild bird outbreaks during the spring migration, suggesting they may be involved in the northward movement of the virus. However, phylogeographic mapping of HPAI H5N1 clades 2.2 and 2.3 did not support dissemination of the virus in a northern direction along the migration corridor. In particular, two subclades (2.2.1 and 2.3.2) moved in a strictly southern direction in contrast to our spatio-temporal analysis of bird migration. Our attempt to reconcile the disciplines of wild bird ecology and HPAI H5N1 virology highlights prospects offered by both approaches as well as their limitations. PMID:22347393

  6. Eco-virological approach for assessing the role of wild birds in the spread of avian influenza H5N1 along the central Asian flyway

    Science.gov (United States)

    Newman, Scott H.; Hill, Nichola J.; Spragens, Kyle A.; Janies, Daniel; Voronkin, Igor O.; Prosser, Diann J.; Yan, Baoping; Lei, Fumin; Batbayar, Nyambayar; Natsagdorj, Tseveenmyadag; Bishop, Charles M.; Butler, Patrick J.; Wikelski, Martin; Balachandran, Sivananinthaperumal; Mundkur, Taej; Douglas, David C.; Takekawa, John Y.

    2012-01-01

    A unique pattern of highly pathogenic avian influenza (HPAI) H5N1 outbreaks has emerged along the Central Asia Flyway, where infection of wild birds has been reported with steady frequency since 2005. We assessed the potential for two hosts of HPAI H5N1, the bar-headed goose (Anser indicus) and ruddy shelduck (Tadorna tadorna), to act as agents for virus dispersal along this ‘thoroughfare’. We used an eco-virological approach to compare the migration of 141 birds marked with GPS satellite transmitters during 2005–2010 with: 1) the spatio-temporal patterns of poultry and wild bird outbreaks of HPAI H5N1, and 2) the trajectory of the virus in the outbreak region based on phylogeographic mapping. We found that biweekly utilization distributions (UDs) for 19.2% of bar-headed geese and 46.2% of ruddy shelduck were significantly associated with outbreaks. Ruddy shelduck showed highest correlation with poultry outbreaks owing to their wintering distribution in South Asia, where there is considerable opportunity for HPAI H5N1 spillover from poultry. Both species showed correlation with wild bird outbreaks during the spring migration, suggesting they may be involved in the northward movement of the virus. However, phylogeographic mapping of HPAI H5N1 clades 2.2 and 2.3 did not support dissemination of the virus in a northern direction along the migration corridor. In particular, two subclades (2.2.1 and 2.3.2) moved in a strictly southern direction in contrast to our spatio-temporal analysis of bird migration. Our attempt to reconcile the disciplines of wild bird ecology and HPAI H5N1 virology highlights prospects offered by both approaches as well as their limitations.

  7. Orion Exploration Flight Test Post-Flight Inspection and Analysis

    Science.gov (United States)

    Miller, J. E.; Berger, E. L.; Bohl, W. E.; Christiansen, E. L.; Davis, B. A.; Deighton, K. D.; Enriquez, P. A.; Garcia, M. A.; Hyde, J. L.; Oliveras, O. M.

    2017-01-01

    The principal mechanism for developing orbital debris environment models, is to make observations of larger pieces of debris in the range of several centimeters and greater using radar and optical techniques. For particles that are smaller than this threshold, breakup and migration models of particles to returned surfaces in lower orbit are relied upon to quantify the flux. This reliance on models to derive spatial densities of particles that are of critical importance to spacecraft make the unique nature of the EFT-1's return surface a valuable metric. To this end detailed post-flight inspections have been performed of the returned EFT-1 backshell, and the inspections identified six candidate impact sites that were not present during the pre-flight inspections. This paper describes the post-flight analysis efforts to characterize the EFT-1 mission craters. This effort included ground based testing to understand small particle impact craters in the thermal protection material, the pre- and post-flight inspection, the crater analysis using optical, X-ray computed tomography (CT) and scanning electron microscope (SEM) techniques, and numerical simulations.

  8. Labriform propulsion in fishes: kinematics of flapping aquatic flight in the bird wrasse Gomphosus varius (Labridae)

    Science.gov (United States)

    Walker; Westneat

    1997-01-01

    backwards motion of the fin at slow speeds generates a small upward component during slow swimming. Both the alternating sign of the hydrodynamic angle of attack and the observed reduced frequencies suggest that unsteady effects are important in G. varius aquatic flight, especially at low speeds. This study provides a framework for the comparison of aquatic flight by fishes with aerial flight by birds, bats and insects.

  9. Aerodynamics and Ecomorphology of Flexible Feathers and Morphing Bird Wings

    Science.gov (United States)

    Klaassen van Oorschot, Brett

    Birds are talented fliers capable of vertical take-off and landing, navigating turbulent air, and flying thousands of miles without rest. How is this possible? What allows birds to exploit the aerial environment with such ease? In part, it may be because bird wings are unlike any engineered wing. They are flexible, strong, lightweight, and dynamically capable of changes in shape on a nearly instantaneous basis (Rayner, 1988; Tobalske, 2007). Moreover, much of this change is passive, modulated only by changes in airflow angle and velocity. Birds actively morph their wings and their feathers morph passively in response to airflow to meet aerodynamic demands. Wings are highly adapted to myriad aeroecological factors and aerodynamic conditions (e.g. Lockwood et al., 1998; Bowlin and Winkler, 2004). This dissertation contains the results of my research on the complexities of morphing avian wings and feathers. I chose to study three related-but-discrete aspects of the avian wing: 1) the aerodynamics of morphing wings during take-off and gliding flight, 2) the presence and significance of wing tip slots across the avian clade, and 3) the aerodynamic role of the emarginate primary feathers that form these wing tip slots. These experiments ask fundamental questions that have intrigued me since childhood: Why do birds have different wing shapes? And why do some birds have slotted wing tips? It's fair to say that you will not find definitive answers here--rather, you will find the methodical, incremental addition of new hypotheses and empirical evidence which will serve future researchers in their own pursuits of these questions. The first chapter explores active wing morphing in two disparate aerodynamic regimes: low-advance ratio flapping (such as during takeoff) and high-advance ratio gliding. This chapter was published in the Journal of Experimental Biology (Klaassen van Oorschot et al., 2016) with the help of an undergraduate researcher, Emily Mistick. We found that wing

  10. Tornadic storm avoidance behavior in breeding songbirds

    Science.gov (United States)

    Streby, Henry M.; Kramer, Gunnar R.; Peterson, Sean M.; Lehman, Justin A.; Buehler, David A.; Andersen, David E.

    2015-01-01

    Migration is a common behavior used by animals of many taxa to occupy different habitats during different periods. Migrant birds are categorized as either facultative (i.e., those that are forced to migrate by some proximal cue, often weather) or obligate (i.e., those that migrate on a regular cycle). During migration, obligate migrants can curtail or delay flights in response to inclement weather or until favorable winds prevail, and they can temporarily reorient or reverse direction when ecological or meteorological obstacles are encountered. However, it is not known whether obligate migrants undertake facultative migrations and make large-scale movements in response to proximal cues outside of their regular migration periods. Here, we present the first documentation of obligate long-distance migrant birds undertaking a facultative migration, wherein breeding golden-winged warblers (Vermivora chrysoptera) carrying light-level geolocators performed a >1,500 km 5-day circumvention of a severe tornadic storm. The birds evacuated their breeding territories >24 hr before the arrival of the storm and atmospheric variation associated with it. The probable cue, radiating >1,000 km from tornadic storms, perceived by birds and influencing bird behavior and movements, is infrasound (i.e., sound below the range of human hearing). With the predicted increase in severity and frequency of similar storms as anthropogenic climate change progresses, understanding large-scale behavioral responses of animals to such events will be an important objective of future research.

  11. Migration routes and staging areas of Abdim's Storks Ciconia ...

    African Journals Online (AJOL)

    This paper presents the results of a satellite tracking study of seven adult Abdim's Storks Ciconia abdimii that were followed from the nesting areas in southern Niger across the equator to the non-breeding range and back. Post-breeding migration started between early November and early December when all birds ...

  12. Arthropod abundance and seasonal bird use of bottomland forest harvest gaps

    Science.gov (United States)

    Christopher E. Moorman; Liessa T. Woen; John C. Kilgo; James L. Hanula; Scott Horn; Michael D. Ulyshen

    2012-01-01

    We investigated the influence of arthropod abundance and vegetation structure on shifts in avian use of canopy gap, gap edge, and surrounding forest understory in a bottomland hardwood forest in the Upper Coastal Plain of South Carolina. We compared captures of foliage-gleaning birds among locations during four periods (spring migration, breeding, post-breeding, and...

  13. Using wind tunnels to predict bird mortality in wind farms: the case of griffon vultures.

    Directory of Open Access Journals (Sweden)

    Manuela de Lucas

    Full Text Available BACKGROUND: Wind farms have shown a spectacular growth during the last 15 years. Avian mortality through collision with moving rotor blades is well-known as one of the main adverse impacts of wind farms. In Spain, the griffon vulture incurs the highest mortality rates in wind farms. METHODOLOGY/PRINCIPAL FINDINGS: As far as we know, this study is the first attempt to predict flight trajectories of birds in order to foresee potentially dangerous areas for wind farm development. We analyse topography and wind flows in relation to flight paths of griffon vultures, using a scaled model of the wind farm area in an aerodynamic wind tunnel, and test the difference between the observed flight paths of griffon vultures and the predominant wind flows. Different wind currents for each wind direction in the aerodynamic model were observed. Simulations of wind flows in a wind tunnel were compared with observed flight paths of griffon vultures. No statistical differences were detected between the observed flight trajectories of griffon vultures and the wind passages observed in our wind tunnel model. A significant correlation was found between dead vultures predicted proportion of vultures crossing those cells according to the aerodynamic model. CONCLUSIONS: Griffon vulture flight routes matched the predominant wind flows in the area (i.e. they followed the routes where less flight effort was needed. We suggest using these kinds of simulations to predict flight paths over complex terrains can inform the location of wind turbines and thereby reduce soaring bird mortality.

  14. Migration patterns and movements of sandhill cranes wintering in central and southwestern Louisiana

    Science.gov (United States)

    King, Sammy L.; Pierce, Aaron R.; Hersey, Kent R.; Winstead, Nicholas; Hartup, Barry K.

    2010-01-01

    In this study we trapped wintering sandhill cranes (Grus canadensis) in Louisiana and fitted them with satellite transmitters to determine their migration routes. Four of the 6 sandhill cranes with validated locations and a terminus point used the Central Flyway for spring migration; 2 of these 4 (the only 2 for which we have data) also used the Central Flyway for fall migration. Two of the 6 birds used the Mississippi Flyway for spring migration. The results of this study suggest that reintroduced whooping cranes (G. americana) that intermix and migrate with sandhill cranes that winter in Louisiana may enter the Central Flyway. In addition, the Mississippi Flyway is a viable option to use as a migration route for whooping cranes if they are reintroduced in Louisiana.

  15. Linking animals aloft with the terrestrial landscape

    Science.gov (United States)

    Buler, Jeffrey J.; Barrow, Wylie; Boone, Matthew; Dawson, Deanna K.; Diehl, Robert H.; Moore, Frank R.; Randall, Lori A.; Schreckengost, Timothy; Smolinsky, Jaclyn A.

    2018-01-01

    Despite using the aerosphere for many facets of their life, most flying animals (i.e., birds, bats, some insects) are still bound to terrestrial habitats for resting, feeding, and reproduction. Comprehensive broad-scale observations by weather surveillance radars of animals as they leave terrestrial habitats for migration or feeding flights can be used to map their terrestrial distributions either as point locations (e.g., communal roosts) or as continuous surface layers (e.g., animal densities in habitats across a landscape). We discuss some of the technical challenges to reducing measurement biases related to how radars sample the aerosphere and the flight behavior of animals. We highlight a recently developed methodological approach that precisely and quantitatively links the horizontal spatial structure of birds aloft to their terrestrial distributions and provides novel insights into avian ecology and conservation across broad landscapes. Specifically, we present case studies that (1) elucidate how migrating birds contend with crossing ecological barriers and extreme weather events, (2) identify important stopover areas and habitat use patterns of birds along their migration routes, and (3) assess waterfowl response to wetland habitat management and restoration. These studies aid our understanding of how anthropogenic modification of the terrestrial landscape (e.g., urbanization, habitat management), natural geographic features, and weather (e.g., hurricanes) can affect the terrestrial distributions of flying animals.

  16. Long-distance travellers stopover for longer: a case study with spoonbills staying in North Iberia

    OpenAIRE

    Navedo , Juan G.; Orizaola , Germán; Masero , José A.; Overdijk , Otto; Sánchez-Guzmán , Juan M.

    2010-01-01

    Abstract Long-distance migration is widespread among birds, connecting breeding and wintering areas through a set of stopover localities where individuals refuel and/or rest. The extent of the stopover is critical in determining the migratory strategy of a bird. Here, we examined the relationship between minimum length of stay of PVC-ringed birds in a major stopover site and the remaining flight distance to the overwintering area in the Eurasian spoonbill (Platalea l. leucorodia) d...

  17. Laser Fluorescence Illuminates the Soft Tissue and Life Habits of the Early Cretaceous Bird Confuciusornis.

    Directory of Open Access Journals (Sweden)

    Amanda R Falk

    Full Text Available In this paper we report the discovery of non-plumage soft tissues in Confuciusornis, a basal beaked bird from the Early Cretaceous Jehol Biota in northeastern China. Various soft tissues are visualized and interpreted through the use of laser-stimulated fluorescence, providing much novel anatomical information about this early bird, specifically reticulate scales covering the feet, and the well-developed and robust pro- and postpatagium. We also include a direct comparison between the forelimb soft tissues of Confuciusornis and modern avian patagia. Furthermore, apparently large, fleshy phalangeal pads are preserved on the feet. The reticulate scales, robust phalangeal pads as well as the highly recurved pedal claws strongly support Confuciusornis as an arboreal bird. Reticulate scales are more rounded than scutate scales and do not overlap, thus allowing for more flexibility in the toe. The extent of the pro- and postpatagium and the robust primary feather rachises are evidence that Confuciusornis was capable of powered flight, contrary to previous reports suggesting otherwise. A unique avian wing shape is also reconstructed based on plumage preserved. These soft tissues combined indicate an arboreal bird with the capacity for short-term (non-migratory flight, and suggest that, although primitive, Confuciusornis already possessed many relatively advanced avian anatomical characteristics.

  18. Columbia River ESI: BIRDS (Bird Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for wading birds, shorebirds, waterfowl, diving birds, seabirds, passerine birds, gulls, and terns in...

  19. Autumn phenology and morphometrics in the Garden Warbler Sylvia borin at the Ottenby Bird Observatory, Sweden

    DEFF Research Database (Denmark)

    Iwajomo, Soladoye B.; Hedenström, Anders; Ottosson, Ulf

    2012-01-01

    not significantly vary over the years. Median passage dates were 24 August, 30 August and 2 September for adults, juveniles and birds of unknown age, respectively. Median passage did not change significantly over the years. Among adults, larger individuals passed the observatory earlier than smaller individuals......Trapping and ringing near ecological barriers can provide useful information about the migration strategies of bird species. In this paper we analyzed ringing data of the Garden Warbler, collected within the period of 1950-2008 at the Ottenby Bird Observatory, south-eastern Sweden, and describe...

  20. Optimal swimming speed in head currents and effects on distance movement of winter-migrating fish.

    Directory of Open Access Journals (Sweden)

    Jakob Brodersen

    Full Text Available Migration is a commonly described phenomenon in nature that is often caused by spatial and temporal differences in habitat quality. However, as migration requires energy, the timing of migration may depend not only on differences in habitat quality, but also on temporal variation in migration costs. Such variation can, for instance, arise from changes in wind or current velocity for migrating birds and fish, respectively. Whereas behavioural responses of birds to such changing environmental conditions have been relatively well described, this is not the case for fish, although fish migrations are both ecologically and economically important. We here use passive and active telemetry to study how winter migrating roach regulate swimming speed and distance travelled per day in response to variations in head current velocity. Furthermore, we provide theoretical predictions on optimal swimming speeds in head currents and relate these to our empirical results. We show that fish migrate farther on days with low current velocity, but travel at a greater ground speed on days with high current velocity. The latter result agrees with our predictions on optimal swimming speed in head currents, but disagrees with previously reported predictions suggesting that fish ground speed should not change with head current velocity. We suggest that this difference is due to different assumptions on fish swimming energetics. We conclude that fish are able to adjust both swimming speed and timing of swimming activity during migration to changes in head current velocity in order to minimize energy use.

  1. Activity and migratory flights of individual free-flying songbirds throughout the annual cycle

    DEFF Research Database (Denmark)

    Bäckman, Johan; Andersson, Arne; Alerstam, Thomas

    2017-01-01

    the sampling events. Activity levels were stored on an hourly basis throughout the annual cycle, allowing periods of resting/sleep, continuous flight and intermediate activity (foraging, breeding) to be distinguished. Measurements from a light sensor were stored from preprogrammed key stationary periods during...... the year to provide control information about geographic location. Successful results, including annual actogram, were obtained for a red-backed shrike Lanius collurio carrying out its annual loop migration between northern Europe and southern Africa. The shrike completed its annual migration by performing...... > 66 (max. 73) nocturnal migratory flights (29 flights in autumn and > 37, max. 44, in spring) adding up to a total of > 434 (max. 495) flight hours. Migratory flights lasted on average 6.6 h with maximum 15.9 h. These flights were aggregated into eight travel episodes (periods of 4-11 nights when...

  2. An evaluation of regression methods to estimate nutritional condition of canvasbacks and other water birds

    Science.gov (United States)

    Sparling, D.W.; Barzen, J.A.; Lovvorn, J.R.; Serie, J.R.

    1992-01-01

    Regression equations that use mensural data to estimate body condition have been developed for several water birds. These equations often have been based on data that represent different sexes, age classes, or seasons, without being adequately tested for intergroup differences. We used proximate carcass analysis of 538 adult and juvenile canvasbacks (Aythya valisineria ) collected during fall migration, winter, and spring migrations in 1975-76 and 1982-85 to test regression methods for estimating body condition.

  3. Detectability of migrating raptors and its effect on bias and precision of trend estimates

    Directory of Open Access Journals (Sweden)

    Eric G. Nolte

    2016-12-01

    Full Text Available Annual counts of migrating raptors at fixed observation points are a widespread practice, and changes in numbers counted over time, adjusted for survey effort, are commonly used as indices of trends in population size. Unmodeled year-to-year variation in detectability may introduce bias, reduce precision of trend estimates, and reduce power to detect trends. We conducted dependent double-observer surveys at the annual fall raptor migration count at Lucky Peak, Idaho, in 2009 and 2010 and applied Huggins closed-capture removal models and information-theoretic model selection to determine the relative importance of factors affecting detectability. The most parsimonious model included effects of observer team identity, distance, species, and day of the season. We then simulated 30 years of counts with heterogeneous individual detectability, a population decline (λ = 0.964, and unexplained random variation in the number of available birds. Imperfect detectability did not bias trend estimation, and increased the time required to achieve 80% power by less than 11%. Results suggested that availability is a greater source of variance in annual counts than detectability; thus, efforts to account for availability would improve the monitoring value of migration counts. According to our models, long-term trends in observer efficiency or migratory flight distance may introduce substantial bias to trend estimates. Estimating detectability with a novel count protocol like our double-observer method is just one potential means of controlling such effects. The traditional approach of modeling the effects of covariates and adjusting the index may also be effective if ancillary data is collected consistently.

  4. Secondarily flightless birds or Cretaceous non-avian theropods?

    Science.gov (United States)

    Kavanau, J Lee

    2010-02-01

    Recent studies by Varricchio et al. reveal that males cared for the eggs of troodontids and oviraptorids, so-called "non-avian theropods" of the Cretaceous, just as do those of most Paleognathic birds (ratites and tinamous) today. Further, the clutches of both groups have large relative volumes, and consist of many eggs of relatively large size. By comparison, clutch care by most extant birds is biparental and the clutches are of small relative volume, and consist of but few small eggs. Varricchio et al. propose that troodontids and oviraptorids were pre-avian and that paternal egg care preceded the origin of birds. On the contrary, unmentioned by them is that abundant paleontological evidence has led several workers to conclude that troodontids and oviraptorids were secondary flightless birds. This evidence ranges from bird-like bodies and bone designs, adapted for climbing, perching, gliding, and ultimately flight, to relatively large, highly developed brains, poor sense of smell, and their feeding habits. Because ratites also are secondarily flightless and tinamous are reluctant, clumsy fliers, the new evidence strengthens the view that troodontids and oviraptorids were secondarily flightless. Although secondary flightlessness apparently favors paternal care of clutches of large, abundant eggs, such care is not likely to have been primitive. There are a suite of previously unknown independent findings that point to the evolution of, first, maternal, followed by biparental egg care in earliest ancestors of birds. This follows from the discovery of remarkable relict avian reproductive behaviors preserved by virtue of the highly conservative nature of vertebrate brain evolution. These behaviors can be elicited readily by exposing breeding birds to appropriate conditions, both environmental and with respect to their eggs and chicks. They give significant new clues for a coherent theory of avian origin and early evolution.

  5. Differential flight responses of spring staging Teal Anas crecca and Wigeon A. penelope to human vs. natural disturbance

    DEFF Research Database (Denmark)

    Bregnballe, Thomas; Speich, Charlotte; Horsten, Anders

    2017-01-01

    (anglers, cyclists, farming activity) on the flight responses and displacement distances of ducks within uniform habitat along a public path were compared with the birds’ reaction to natural stimuli such as mammals or birds of prey. Excluding the controlled disturbance by a pedestrian, undertaken as part...... of the study, the main cause of flushing in Wigeon was a response to the movements of birds of prey and other birds, especially Lapwings Vanellus vanellus performing flight displays. For Teal, birds of prey accounted for around half of the flushes, with other birds accounting for one third of the flushes....... Wigeon and Teal were displaced significantly farther by human activities than by natural causes. We tested whether the ducks reacted differently to natural disturbances shortly after disturbance by a pedestrian by comparing response patterns to natural stimuli within the first hour following disturbance...

  6. Isolation and genetic characterization of avian influenza viruses isolated from wild birds in the Azov-Black Sea Region of Ukraine (2001–2012)

    Science.gov (United States)

    Wild bird surveillance for avian influenza virus (AIV) was conducted from 2001 to 2012 in the Azov - Black Sea region of the Ukraine, considered part of the transcontinental wild bird migration routes from northern Asia and Europe to the Mediterranean, Africa, and southwest Asia. A total of 6281 sam...

  7. Shades of green: A bird's eye view of wind energy; L'energie eolienne et son impact sur les oiseaux

    Energy Technology Data Exchange (ETDEWEB)

    Whittam, B.; Kingsley, A.

    2003-03-31

    The issue of birds being killed by wind turbines is discussed. The substance of the argument is that contrary to beliefs held primarily by those opposed to wind turbine developments, when correctly sited, wind turbines appear to have relatively little impact on birds. Historically, 'bird-kill' was a significant factor in the 1980s when a significant number of raptors were killed by wind turbines and their associated power lines in California, Tennessee, Spain and the Netherlands, where many turbines were located on major bird migration routes. Based on experiences learned from these occurrences, several countries have produced bird-focused guidelines for the siting of wind turbines. In Canada, Bird Studies Canada was recently contracted by Environment Canada to produce guidelines for the environmental assessment of wind turbine projects related to birds. The objective of the guidelines is to help prevent adverse impacts on birds, whether the impact is related to habitat disturbance or collision. Based on American studies, it is estimated that 2.19 birds are killed annually at each wind turbine in California; the estimated fatality rate elsewhere in the United States is 1.83. That works out to 33,000 dead birds (based on 15,000 wind turbines), a large number, but relatively small when compared with the millions of birds that travel over windfarms each year, or when compared to the many millions of birds that die annually due to collisions with transmission lines, vehicles, buildings and communication towers. Nevertheless, there is room for concern. Bird Studies Canada is particularly concerned about the growing offshore wind industry and its potential to disrupt songbird migration, waterfowl staging areas and the prey base of seabirds. In general, Bird Studies Canada advises against siting large wind facilities in areas heavily travelled by birds, and is firmly opposed to placing wind turbines in areas known to provide critical habitat for Species At Risk

  8. Efficiency of Lift Production in Flapping and Gliding Flight of Swifts

    Science.gov (United States)

    Henningsson, Per; Hedenström, Anders; Bomphrey, Richard J.

    2014-01-01

    Many flying animals use both flapping and gliding flight as part of their routine behaviour. These two kinematic patterns impose conflicting requirements on wing design for aerodynamic efficiency and, in the absence of extreme morphing, wings cannot be optimised for both flight modes. In gliding flight, the wing experiences uniform incident flow and the optimal shape is a high aspect ratio wing with an elliptical planform. In flapping flight, on the other hand, the wing tip travels faster than the root, creating a spanwise velocity gradient. To compensate, the optimal wing shape should taper towards the tip (reducing the local chord) and/or twist from root to tip (reducing local angle of attack). We hypothesised that, if a bird is limited in its ability to morph its wings and adapt its wing shape to suit both flight modes, then a preference towards flapping flight optimization will be expected since this is the most energetically demanding flight mode. We tested this by studying a well-known flap-gliding species, the common swift, by measuring the wakes generated by two birds, one in gliding and one in flapping flight in a wind tunnel. We calculated span efficiency, the efficiency of lift production, and found that the flapping swift had consistently higher span efficiency than the gliding swift. This supports our hypothesis and suggests that even though swifts have been shown previously to increase their lift-to-drag ratio substantially when gliding, the wing morphology is tuned to be more aerodynamically efficient in generating lift during flapping. Since body drag can be assumed to be similar for both flapping and gliding, it follows that the higher total drag in flapping flight compared with gliding flight is primarily a consequence of an increase in wing profile drag due to the flapping motion, exceeding the reduction in induced drag. PMID:24587260

  9. Efficiency of lift production in flapping and gliding flight of swifts.

    Directory of Open Access Journals (Sweden)

    Per Henningsson

    Full Text Available Many flying animals use both flapping and gliding flight as part of their routine behaviour. These two kinematic patterns impose conflicting requirements on wing design for aerodynamic efficiency and, in the absence of extreme morphing, wings cannot be optimised for both flight modes. In gliding flight, the wing experiences uniform incident flow and the optimal shape is a high aspect ratio wing with an elliptical planform. In flapping flight, on the other hand, the wing tip travels faster than the root, creating a spanwise velocity gradient. To compensate, the optimal wing shape should taper towards the tip (reducing the local chord and/or twist from root to tip (reducing local angle of attack. We hypothesised that, if a bird is limited in its ability to morph its wings and adapt its wing shape to suit both flight modes, then a preference towards flapping flight optimization will be expected since this is the most energetically demanding flight mode. We tested this by studying a well-known flap-gliding species, the common swift, by measuring the wakes generated by two birds, one in gliding and one in flapping flight in a wind tunnel. We calculated span efficiency, the efficiency of lift production, and found that the flapping swift had consistently higher span efficiency than the gliding swift. This supports our hypothesis and suggests that even though swifts have been shown previously to increase their lift-to-drag ratio substantially when gliding, the wing morphology is tuned to be more aerodynamically efficient in generating lift during flapping. Since body drag can be assumed to be similar for both flapping and gliding, it follows that the higher total drag in flapping flight compared with gliding flight is primarily a consequence of an increase in wing profile drag due to the flapping motion, exceeding the reduction in induced drag.

  10. The study and ringing of Palaearctic birds at Ngulia Lodge, Tsavo ...

    African Journals Online (AJOL)

    ... in larger catches, and small Kenya-based teams were sometimes able to handle over 1000 birds per night/ .... data can be treated according to the capture regime used. The amplified ... Martins Delichon urbicum. Annual Barn ...... and northern Tanzania, a so-called “split flight feather moult” strategy (Lindström et al. 1992).

  11. Bird ringing in Slovenia in 2014 and results of the first telemetry study of an African migrant

    Directory of Open Access Journals (Sweden)

    Vrezec Al

    2015-12-01

    Full Text Available In 2014, 162 bird species were recorded during the bird ringing activities in Slovenia. Of 155 species, 62,275 birds were ringed, and 107 recoveries of birds ringed in Slovenia and found abroad, 148 foreign recoveries in Slovenia and 1395 local recoveries were recorded. The most frequently ringed species were Blackcap Sylvia atricapilla and Great Tit Parus major. As far as ringed nestlings are concerned, Great Tits and Barn Swalllows Hirundo rustica predominated. Considering the recoveries ringed of found birds abroad, the commonest were Black-headed Gulls Chroicocephalus ridibundus and Mute Swans Cygnus olor. The farthest recovery was a Barn Swallow Hirundo rustica found in the Democratic Republic of Congo (5171 km away. Among the more interesting finds was also the so far southernmost recovery of a Sand Martin Riparia riparia found in Israel. Let us also mention the first recovery of a Corncrake Crex crex, which bred and was ringed in 2013 at Planinsko polje (central Slovenia and was found in the 2014 breeding season in the Czech Republic. Among rare species, two Little Buntings Emberiza pusilla were caught and ringed. After nine years, the Roller Coracias garrulus bred again in Slovenia in 2014 and its nestlings were ringed. The paper also brings the description of the migration route of the first African migrant, the Black Stork Ciconia nigra, marked with a GPS/GSM telemetric device, which migrated across the Adriatic Sea, Sicily and Sahara to Nigeria.

  12. Predicting Migratory Corridors of White Storks, Ciconia ciconia, to Enhance Sustainable Wind Energy Planning: A Data-Driven Agent-Based Model

    Directory of Open Access Journals (Sweden)

    Francis Oloo

    2018-05-01

    Full Text Available White storks (Ciconia ciconia are birds that make annual long-distance migration flights from their breeding grounds in the Northern Hemisphere to the south of Africa. These trips take place in the winter season, when the temperatures in the North fall and food supply drops. White storks, because of their large size, depend on the wind, thermals, and orographic characteristics of the environment in order to minimize their energy expenditure during flight. In particular, the birds adopt a soaring behavior in landscapes where the thermal uplift and orographic updrafts are conducive. By attaining suitable soaring heights, the birds then use the wind characteristics to glide for hundreds of kilometers. It is therefore expected that white storks would prefer landscapes that are characterized by suitable wind and thermal characteristics, which promote the soaring and gliding behaviors. However, these same landscapes are also potential sites for large-scale wind energy generation. In this study, we used the observed data of the white stork movement trajectories to specify a data-driven agent-based model, which simulates flight behavior of the white storks in a dynamic environment. The data on the wind characteristics and thermal uplift are dynamically changed on a daily basis so as to mimic the scenarios that the observed birds experienced during flight. The flight corridors that emerge from the simulated flights are then combined with the predicted surface on the wind energy potential, in order to highlight the potential risk of collision between the migratory white storks and hypothetical wind farms in the locations that are suitable for wind energy developments. This work provides methods that can be adopted to assess the overlap between wind energy potential and migratory corridors of the migration of birds. This can contribute to achieving sustainable trade-offs between wind energy development and conservation of wildlife and, hence, handling the

  13. Migratory decisions in birds: Extent of genetic versus environmental control

    Science.gov (United States)

    Ogonowski, M.S.; Conway, C.J.

    2009-01-01

    Migration is one of the most spectacular of animal behaviors and is prevalent across a broad array of taxa. In birds, we know much about the physiological basis of how birds migrate, but less about the relative contribution of genetic versus environmental factors in controlling migratory tendency. To evaluate the extent to which migratory decisions are genetically determined, we examined whether individual western burrowing owls (Athene cunicularia hypugaea) change their migratory tendency from one year to the next at two sites in southern Arizona. We also evaluated the heritability of migratory decisions by using logistic regression to examine the association between the migratory tendency of burrowing owl parents and their offspring. The probability of migrating decreased with age in both sexes and adult males were less migratory than females. Individual owls sometimes changed their migratory tendency from one year to the next, but changes were one-directional: adults that were residents during winter 2004-2005 remained residents the following winter, but 47% of adults that were migrants in winter 2004-2005 became residents the following winter. We found no evidence for an association between the migratory tendency of hatch-year owls and their male or female parents. Migratory tendency of hatch-year owls did not differ between years, study sites or sexes or vary by hatching date. Experimental provision of supplemental food did not affect these relationships. All of our results suggest that heritability of migratory tendency in burrowing owls is low, and that intraspecific variation in migratory tendency is likely due to: (1) environmental factors, or (2) a combination of environmental factors and non-additive genetic variation. The fact that an individual's migratory tendency can change across years implies that widespread anthropogenic changes (i.e., climate change or changes in land use) could potentially cause widespread changes in the migratory tendency of

  14. Thick-billed murres from the High Arctic have the luxury of being lazy!

    DEFF Research Database (Denmark)

    Linnebjerg, Jannie; Tremblay, Yann; Mosbech, Anders

    cold waters where energy consumption is low. This causes potential problems for homoeothermic predators, which require constant access to nutritious prey to survive or large body lipid reserves. Diving birds are particularly vulnerable to periods of low prey availability and many species therefore......Aquatic environments in the temperate, boreal and arctic climate zones are highly seasonal in terms of biological productivity. Many poikilothermic aquatic organisms survive the winter, when food availability is low, by reducing their activity levels and/or performing vertical migrations to deep...... resolve this by migrating to warmer waters, where locating food is energetically less challenging. Migration by flight, however, is extremely energetically costly for birds with wings specialized for underwater swimming. Little is known of how they manage to obtain sufficient energy during migration...

  15. Risk evaluation for federally listed (roseate tern, piping plover) or candidate (red knot) bird species in offshore waters: A first step for managing the potential impacts of wind facility development on the Atlantic Outer Continental Shelf

    Energy Technology Data Exchange (ETDEWEB)

    Burger, Joanna [Division of Life Sciences, Rutgers University, Piscataway, NJ 08854-8082 (United States); Conserve Wildlife, 516 Farnsworth Avenue, Bordentown, NJ 08505 (United States); Gordon, Caleb; Newman, James; Forcey, Greg [Pandion Systems, Inc. 102 NE 10th Ave, Gainesville, FL 32601 (United States); Lawrence, J. [Conserve Wildlife, 516 Farnsworth Avenue, Bordentown, NJ 08505 (United States); Vlietstra, Lucy [Department of Science, US Coast Guard Academy, 27 Mohegan Drive, New London, CT 06320 (United States)

    2011-01-15

    With a worldwide increase in attention toward developing a reliance on renewable energy, there is a need to evaluate the effects of these facilities (solar, wind, hydropower) on ecosystems. We conduct a hazard and risk evaluation for three species of birds that are listed, or candidates for listing, as federally threatened or endangered in the US, and that might occur offshore on the Atlantic Outer Continental Shelf (AOCS) where wind power facilities could be developed. Our objectives were to: 1) provide conceptual models for exposure for each species, and 2) examine potential exposure and hazards of roseate tern (Sterna dougallii) and piping plover (Charadrius melodus, both federally endangered in the US) and red knot (Calidris canutus rufa, candidate species) in the AOCS. We used a weight-of-evidence approach to evaluate information from a review of technical literature. We developed conceptual models to examine the relative vulnerability of each species as a function of life stage and cycle (breeding, staging, migratory, wintering). These methods are useful for conducting environmental assessments when empirical data are insufficient for a full risk assessment. We determined that 1) Roseate terns are likely to be exposed to risk during the migratory and breeding season when they occur in the AOCS, as well as while staging. 2) Piping plovers are not likely to be at risk during the breeding season, but may be at risk during spring or fall migrations. Risk to this species is likely to be low from turbines located far from land as this species migrates mainly along the coast. 3) Red knots are potentially exposed to some risk during migration, especially long-distance migrants whose migratory routes take them over the AOCS. More information is required on exact spatio-temporal migration routes, flight altitudes (especially during ascent and descent), and behavioral avoidance of turbines by birds to ascertain their risk. (author)

  16. Mechanical Constraints on Flight at High Elevation Decrease Maneuvering Performance of Hummingbirds.

    Science.gov (United States)

    Segre, Paolo S; Dakin, Roslyn; Read, Tyson J G; Straw, Andrew D; Altshuler, Douglas L

    2016-12-19

    High-elevation habitats offer ecological advantages including reduced competition, predation, and parasitism [1]. However, flying organisms at high elevation also face physiological challenges due to lower air density and oxygen availability [2]. These constraints are expected to affect the flight maneuvers that are required to compete with rivals, capture prey, and evade threats [3-5]. To test how individual maneuvering performance is affected by elevation, we measured the free-flight maneuvers of male Anna's hummingbirds in a large chamber translocated to a high-elevation site and then measured their performance at low elevation. We used a multi-camera tracking system to identify thousands of maneuvers based on body position and orientation [6]. At high elevation, the birds' translational velocities, accelerations, and rotational velocities were reduced, and they used less demanding turns. To determine how mechanical and metabolic constraints independently affect performance, we performed a second experiment to evaluate flight maneuvers in an airtight chamber infused with either normoxic heliox, to lower air density, or nitrogen, to lower oxygen availability. The hypodense treatment caused the birds to reduce their accelerations and rotational velocities, whereas the hypoxic treatment had no significant effect on maneuvering performance. Collectively, these experiments reveal how aerial maneuvering performance changes with elevation, demonstrating that as birds move up in elevation, air density constrains their maneuverability prior to any influence of oxygen availability. Our results support the hypothesis that changes in competitive ability at high elevations are the result of mechanical limits to flight performance [7]. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Predicting migratory flight altitudes by physiological migration models

    NARCIS (Netherlands)

    Liechti, F.; Klaassen, M.R.J.; Bruderer, B.

    2000-01-01

    Using the altitudinal profiles of wind, temperature, pressure, and humidity in three flight models, we tried to explain the altitudinal distributions of nocturnal migrants recorded by radar above a desert in southern Israel. In the simplest model, only the tailwind component was used as a predictor

  18. Migration patterns of the Osprey Pandion haliaetus on the Eastern ...

    African Journals Online (AJOL)

    We analysed migration strategies of the Osprey Pandion haliaetus on the poorly studied Eastern European– East African flyway. Four adult birds were equipped with GPS-based satellite-transmitters or data-loggers in their breeding sites in Estonia (north-eastern Europe) and tracked to their wintering grounds in Africa and ...

  19. Intra- and inter-individual variation in flight direction in a migratory butterfly co-vary with individual mobility.

    Science.gov (United States)

    Larranaga, Nicolas; Baguette, Michel; Calvez, Olivier; Trochet, Audrey; Ducatez, Simon; Legrand, Delphine

    2013-08-15

    Flight direction is a major component of an animal's migratory success. However, few studies have focused on variation in flight direction both between and within individuals, which is likely to be correlated with other traits implied in migration processes. We report patterns of intra- and inter-individual variation in flight direction in the large white butterfly Pieris brassicae. The presence of inter-individual variation in flight direction for individuals tested in the same conditions suggests that this trait is inherited in P. brassicae and we propose that a rapid loss of migratory skills may exist in the absence of selection for migration. The magnitude of intra-individual variation was negatively correlated to two surrogates of the potential for migration: mobility and wing length. Highly mobile and longed-winged individuals within the same family were found to fly in similar directions, whereas less mobile and short-winged individuals displayed divergent flight direction compared with the average direction of their kin. There was also a negative correlation between the variance to the mean flight direction of a family and its average mobility, but no correlation with wing length. We discuss these issues in terms of the evolution of traits potentially implied in both migration and dispersal in P. brassicae.

  20. Climate change and timing of avian breeding and migration throughout Europe

    NARCIS (Netherlands)

    Both, Christiaan; te Marvelde, Luc

    2007-01-01

    Bird breeding and spring migration phenology have advanced in response to climate change, but the effects differ between sites. Here, we examine the geographical variation in laying-date trends in a short-distance migrant, the European starling Sturnus vulgaris, and a long-distance migrant, the pied

  1. Understanding the biological concept "bird": A kindergarten case study

    Science.gov (United States)

    Buchholz, Dilek

    The purpose of this qualitative, multiple case study of 14 students in a metropolitan public school in the Deep South was to find out, during a period of three months, what these kindergarten-aged children knew about birds, whether this knowledge represented current scientific thought, if such science instruction meaningfully affected their prior knowledge, and if so, what the factors during instruction that seemed to influence their understanding of the concept of bird were. The research was conducted in three phases; preinstruction interviews, instruction, and postinstruction interviews. The theoretical framework for this research was based on the Human Constructivism theory of learning (Mintzes, Wandersee and Novak, 1997). Instructional materials consisted of carefully chosen books (both fiction and non-fiction), guest speakers, field trips, a live bird in the classroom, students' observation journals, teacher-made classification and sorting activities, and picture-based concept maps. The findings suggest that young children's knowledge of birds was limited chiefly to birds' anatomical and morphological characteristics, with repeated references being made by the children to human characteristics. There was a positive, significant difference in young children's pre- and postinstruction scientific knowledge of birds. Although performance varied from child to child after instruction, most children were able to identify some common birds by name. Just one child resisted conceptual change. Kindergarten children's basic knowledge of bird behavior was limited to flight and eating. Although the children had more conceptual knowledge at the end, understanding still appeared to be shallow. The children did develop their skill in observing markedly. It also became evident that these kindergarten children needed more (a) experience in asking questions, (b) practice in techniques of visual representation, and (c) language development in order to be able to explain what they

  2. Migration monitoring with automated technology

    Science.gov (United States)

    Rhonda L. Millikin

    2005-01-01

    Automated technology can supplement ground-based methods of migration monitoring by providing: (1) unbiased and automated sampling; (2) independent validation of current methods; (3) a larger sample area for landscape-level analysis of habitat selection for stopover, and (4) an opportunity to study flight behavior. In particular, radar-acoustic sensor fusion can...

  3. Ontogenetic development of migration: Lagrangian drift trajectories suggest a new paradigm for sea turtles

    DEFF Research Database (Denmark)

    Hays, Graeme C.; Fossette, Sabrina; Katselidis, Kostas A.

    2010-01-01

    Long distance migration occurs in a wide variety of taxa including birds, insects, fishes, mammals and reptiles. Here, we provide evidence for a new paradigm for the determinants of migration destination. As adults, sea turtles show fidelity to their natal nesting areas and then at the end...... dispersion that would be experienced by hatchlings. Hence, the prevailing oceanography around nesting areas may be crucial to the selection of foraging sites used by adult sea turtles. This environmental forcing may allow the rapid evolution of new migration destinations if ocean currents alter with climate...

  4. Intraskeletal histovariability, allometric growth patterns, and their functional implications in bird-like dinosaurs.

    Science.gov (United States)

    Prondvai, Edina; Godefroit, Pascal; Adriaens, Dominique; Hu, Dong-Yu

    2018-01-10

    With their elongated forelimbs and variable aerial skills, paravian dinosaurs, a clade also comprising modern birds, are in the hotspot of vertebrate evolutionary research. Inferences on the early evolution of flight largely rely on bone and feather morphology, while osteohistological traits are usually studied to explore life-history characteristics. By sampling and comparing multiple homologous fore- and hind limb elements, we integrate for the first time qualitative and quantitative osteohistological approaches to get insight into the intraskeletal growth dynamics and their functional implications in five paravian dinosaur taxa, Anchiornis, Aurornis, Eosinopteryx, Serikornis, and Jeholornis. Our qualitative assessment implies a considerable diversity in allometric/isometric growth patterns among these paravians. Quantitative analyses show that neither taxa nor homologous elements have characteristic histology, and that ontogenetic stage, element size and the newly introduced relative element precocity only partially explain the diaphyseal histovariability. Still, Jeholornis, the only avialan studied here, is histologically distinct from all other specimens in the multivariate visualizations raising the hypothesis that its bone tissue characteristics may be related to its superior aerial capabilities compared to the non-avialan paravians. Our results warrant further research on the osteohistological correlates of flight and developmental strategies in birds and bird-like dinosaurs.

  5. Bird casualties and wind turbines near the Kreekrak sluices of Zeeland

    International Nuclear Information System (INIS)

    Musters, C.J.M.; Noordervliet, M.A.W.; Ter Keurs, W.J.

    1995-03-01

    The impact of wind turbines on birds was investigated for an estuary, situated near the North Sea coast in the Dutch province of Zeeland, with large amount of bird migration. Five 250 kW, three-bladed 25m, 40 rpm turbines were installed on the western side of a dike. The distance between the turbines is 125 m. Since 1 April 1990 the turbines have been in action almost continuously. The study on the title subject was set up to investigate the number of bird casualties caused by the five wind turbines near the sluices of Kreekrak and the number that may be expected to be caused by a total of 20 turbines. The study also focused on the number of casualties among rare birds in relation to those among the common birds as a result of the wind turbines in the Kreekrak area. An area of 125 x 125 m around each wind turbine, consisting partly of land and partly of water, was searched for dead birds every other day during a period of one year (28 April 1990 - 29 April 1991). During this one-year period, the bodies of 26 birds of 17 different species were found; six birds were certainly or almost certainly killed by the turbines. In three other cases, the birds may have died because of the turbines, while in the case of eight birds, it was not possible to determine the cause of death. The remaining nine birds were not killed by the wind turbines. The annual number of bird victims expected following the installation of 20 wind turbines was estimated at a minimum of 7 and a maximum of 142. For each species a correlation was found between the number of victims and the estimated number of visitors to the area. This suggests that the rare species among the birds were not excessively endangered by the turbines. The number of bird casualties per turbine was low in comparison with the results of other Dutch investigations. On the basis of these results, it is concluded that there is no reason to advise against increasing the number of wind turbines near the sluices of Kreekrak to 20. 3

  6. Prevalence of Taxa of Pasteurellaceae Among Populations of Healthy Captive Psittacine Birds

    DEFF Research Database (Denmark)

    Bisgaard, M.; Xin, Di; Bertelsen, M. F.

    2017-01-01

    Sixty-two strains of Pasteurellaceae-like bacteria were isolated from the tracheas of 87 clinically healthy psittacine birds in two Danish zoos. The isolates were identified by a combination of rpoB and 16S rRNA gene sequencing and by matrix-assisted laser desorption–ionization time of flight. Tw...

  7. Reverse migration: Western European Muslim women’s flights to ISIL territory

    OpenAIRE

    DeSitter, Elizabeth A.

    2015-01-01

    Approved for public release; distribution is unlimited Since early 2014, the Islamic State of Iraq and the Levant (ISIL) has increasingly recruited Western Muslim men and women to its radical ideology. This thesis examines why Western European Muslim women—specifically from France and Great Britain—are voluntarily migrating to ISIL territory to support Islamic extremism. It evaluates women’s involvement in previous terrorist movements and proposes five potential motivations for migration: ...

  8. Revealing the control of migratory fueling: An integrated approach combining laboratory and field studies in northern wheatears Oenanthe oenanthe

    Directory of Open Access Journals (Sweden)

    Franz BAIRLEIN,Volker DIERSCHKE, Julia DELINGAT, Cas EIKENAAR, Ivan MAGGINI, Marc BULTE, Heiko SCHMALJOHANN

    2013-06-01

    Full Text Available Migratory birds rely on fueling prior to migratory flights. Fueling in migrants is controlled by intrinsic as well as extrinsic factors. From captive studies we have started understanding the internal mechanisms controlling bird migration. Field studies have demonstrated the effects of external factors, such as food availability, weather, competitors, parasites or diseases, on the stopover behavior of migrants. However, an integrated approach is still missing to study coherently how the innate migration program interacts with the varying environmental cues and to estimate the contribution of the innate migration program and the environment to realized migration. The northern wheatear Oenanthe oenanthe offers a unique opportunity for integrated studies. It breeds across almost the whole Holarctic with just a “gap” between eastern Canada and Alaska. All breeding populations overwinter in sub-Saharan Africa which makes the northern wheatear one of the most long-distant migratory songbirds with extraordinary long non-stop flights across oceans. It is a nocturnal migrant which travels without parental or social aid/guidance. Thus, young birds rely entirely on endogenous mechanisms of timing, route selection and fueling on their first outbound migration. By establishing indoor housing under controlled conditions the endogenous control mechanisms of northern wheatear migration could be revealed. At the same time, environmental factors controlling fueling could be investigated in the field. On migration wheatears occur in a variety of habitats with sparse vegetation where their stopover behavior could be quantitatively studied in the light of “optimal migration” theory by the use of remote balances, radio-tagging and even experimentally manipulated food availability. The present paper summarizes our approach to understand the control of migration in northern wheatears by combining field and laboratory studies at various spatial and temporal

  9. The case for energy harvesting on wildlife in flight

    International Nuclear Information System (INIS)

    Shafer, Michael W; MacCurdy, Robert; Garcia, Ephrahim; Shipley, J Ryan; Winkler, David; Guglielmo, Christopher G

    2015-01-01

    The confluence of advancements in microelectronic components and vibrational energy harvesting has opened the possibility of remote sensor units powered solely from the motion of their hosts. There are numerous applications of such systems, including the development of modern wildlife tracking/data-logging devices. These ‘bio-logging’ devices are typically mass-constrained because they must be carried by an animal. Thus, they have historically traded scientific capability for operational longevity due to restrictions on battery size. Recently, the precipitous decrease in the power requirements of microelectronics has been accompanied by advancements in the area of piezoelectric vibrational energy harvesting. These energy harvesting devices are now capable of powering the type of microelectronic circuits used in bio-logging devices. In this paper we consider the feasibility of employing these vibrational energy harvesters on flying vertebrates for the purpose of powering a bio-logging device. We show that the excess energy available from birds and bats could be harvested without adversely affecting their overall energy budget. We then present acceleration measurements taken on flying birds in a flight tunnel to understand modulation of flapping frequency during steady flight. Finally, we use a recently developed method of estimating the maximum power output from a piezoelectric energy harvester to determine the amount of power that could be practically harvested from a flying bird. The results of this analysis show that the average power output of a piezoelectric energy harvester mounted to a bird or bat could produce more than enough power to run a bio-logging device. We compare the power harvesting capabilities to the energy requirements of an example system and conclude that vibrational energy harvesting on flying birds and bats is viable and warrants further study, including testing. (paper)

  10. [Distribution of aquatic birds in oxidation lagoons of La Paz city in South Baja California, Mexico].

    Science.gov (United States)

    Zamora-Orozco, Elvia Margarita; Carmona, Roberto; Brabata, Georgina

    2007-06-01

    Taxonomic composition, spatial and temporal distribution of aquatic birds in oxidation lagoons (LO) of La Paz city in south Baja California, Mexico, were determined during 24 censuses realized in two-week intervals (April/98-March/99). There are five lagoons of5 Ha each and 17 ha of terrains constantly flooded that serve as feeding areas for cattle and birds. One hundred twenty three species were observed, 75 of which were aquatic birds. A total of 46 041 observations were made (average 1 918 birds/census). Richness and abundance of aquatic birds were influenced mainly by migration of anatids and sandpipers. The first group had the greatest abundance due to its affinity towards fresh water bodies. The terrains were the favorite sites of dabbling ducks (Anas) and sandpipers. In contrast, two of the most abundant species (Oxyura jamaicensis, 12.5% of all species, and Fulica americana, 8.8 %) restricted their presence to the oxidation lagoons. LO presented a bird structure of its own and atypical, according to the dryness of the region.

  11. Qualitative skeletal correlates of wing shape in extant birds (Aves: Neoaves).

    Science.gov (United States)

    Hieronymus, Tobin L

    2015-02-27

    Among living fliers (birds, bats, and insects), birds display relatively high aspect ratios, a dimensionless shape variable that distinguishes long and narrow vs. short and broad wings. Increasing aspect ratio results in a functional tradeoff between low induced drag (efficient cruise) and increased wing inertia (difficult takeoff). Given the wide scope of its functional effects, the pattern of aspect ratio evolution is an important factor that contributes to the substantial ecological and phylogenetic diversity of living birds. However, because the feathers that define the wingtip (and hence wingspan and aspect ratio) often do not fossilize, resolution in the pattern of avian wing shape evolution is obscured by missing information. Here I use a comparative approach to investigate the relationship between skeletal proxies of flight feather attachment and wing shape. An accessory lobe of the internal index process of digit II-1, a bony correlate of distal primary attachment, shows weak but statistically significant relationships to aspect ratio and mass independent of other skeletal morphology. The dorsal phalangeal fossae of digit II-1, which house distal primaries VIII and IX, also show a trend of increased prominence with higher aspect ratio. Quill knobs on the ulna are examined concurrently, but do not show consistent signal with respect to wing shape. Although quill knobs are cited as skeletal correlates of flight performance in birds, their relationship to wing shape is inconsistent among extant taxa, and may reflect diverging selection pressures acting on a conserved architecture. In contrast, correlates of distal primary feather attachment on the major digit show convergent responses to increasing aspect ratio. In light of the diversity of musculoskeletal and integumentary mophology that underlies wing shape in different avian clades, it is unlikely that a single skeletal feature will show consistent predictive power across Neoaves. Confident inference of

  12. A Jurassic avialan dinosaur from China resolves the early phylogenetic history of birds.

    Science.gov (United States)

    Godefroit, Pascal; Cau, Andrea; Dong-Yu, Hu; Escuillié, François; Wenhao, Wu; Dyke, Gareth

    2013-06-20

    The recent discovery of small paravian theropod dinosaurs with well-preserved feathers in the Middle-Late Jurassic Tiaojishan Formation of Liaoning Province (northeastern China) has challenged the pivotal position of Archaeopteryx, regarded from its discovery to be the most basal bird. Removing Archaeopteryx from the base of Avialae to nest within Deinonychosauria implies that typical bird flight, powered by the forelimbs only, either evolved at least twice, or was subsequently lost or modified in some deinonychosaurians. Here we describe the complete skeleton of a new paravian from the Tiaojishan Formation of Liaoning Province, China. Including this new taxon in a comprehensive phylogenetic analysis for basal Paraves does the following: (1) it recovers it as the basal-most avialan; (2) it confirms the avialan status of Archaeopteryx; (3) it places Troodontidae as the sister-group to Avialae; (4) it supports a single origin of powered flight within Paraves; and (5) it implies that the early diversification of Paraves and Avialae took place in the Middle-Late Jurassic period.

  13. First description of autumn migration of Sooty Falcon Falco concolor from the United Arab Emirates to Madagascar using satellite telemetry

    Science.gov (United States)

    Javed, Sàlim; Douglas, David C.; Khan, Shahid Noor; Nazeer Shah, Junid; Ali Al Hammadi, Abdullah

    2012-01-01

    The movement and migration pattern of the 'Near Threatened' Sooty Falcon Falco concolor is poorly known. Sooty Falcons breed on the islands of the Arabian Gulf after arriving from their non-breeding areas that are mainly in Madagascar. In the first satellite tracking of the species we fitted a 9.5 g Argos solar powered transmitter on an adult breeding Sooty Falcon off the western coast of Abu Dhabi in the United Arab Emirates. The bird successfully undertook autumn migration to Madagascar, a known wintering area for the species. We document the Sooty Falcon's autumn migration route and stop-over sites. The adult Sooty Falcon initiated its migration at night and with tailwinds, and travelled mainly during daytime hours for 13 days over an inland route of more than 5,656 km. The three stop-over sites in East Africa were characterised by moderate to sparse shrub cover associated with potential sources of water. We discuss the migration pattern of the tracked bird in relation to importance of non-breeding areas for Sooty Falcons and recent declines in numbers in their breeding range.

  14. Applying citizen-science data and mark-recapture models to estimate numbers of migrant golden eagles in an important bird area in eastern North America

    Science.gov (United States)

    Dennhardt, Andrew J.; Duerr, Adam E.; Brandes, David; Katzner, Todd

    2017-01-01

    Estimates of population abundance are important to wildlife management and conservation. However, it can be difficult to characterize the numbers of broadly distributed, low-density, and elusive bird species. Although Golden Eagles (Aquila chrysaetos) are rare, difficult to detect, and broadly distributed, they are concentrated during their autumn migration at monitoring sites in eastern North America. We used hawk-count data collected by citizen scientists in a virtual mark–recapture modeling analysis to estimate the numbers of Golden Eagles that migrate in autumn along Kittatinny Ridge, an Important Bird Area in Pennsylvania, USA. In order to evaluate the sensitivity of our abundance estimates to variation in eagle capture histories, we applied candidate models to 8 different sets of capture histories, constructed with or without age-class information and using known mean flight speeds 6 1, 2, 4, or 6 SE for eagles to travel between hawk-count sites. Although some abundance estimates were produced by models that poorly fitted the data (ĉ > 3.0), 2 sets of population estimates were produced by acceptably performing models (cˆ less than or equal to 3.0). Application of these models to count data from November, 2002–2011, suggested a mean population abundance of 1,354 6 117 SE (range: 873–1,938). We found that Golden Eagles left the ridgeline at different rates and in different places along the route, and that typically ,50% of individuals were detected at the hawk-count sites. Our study demonstrates a useful technique for estimating population abundance that may be applicable to other migrant species that are repeatedly detected at multiple monitoring sites along a topographic diversion or leading line.

  15. Experimental evidence of human recreational disturbance effects on bird-territory establishment.

    Science.gov (United States)

    Bötsch, Yves; Tablado, Zulima; Jenni, Lukas

    2017-07-12

    The worldwide increase in human outdoor activities raises concerns for wildlife. Human disturbances, even at low levels, are likely to impact species during sensitive periods of the annual cycle. However, experimental studies during the putative sensitive period of territory establishment of birds which not only investigate low disturbance levels, but which also exclude the effect of habitat modification (e.g. walking trails) are lacking. Here, we experimentally disturbed birds in forest plots by walking through twice a day during territory establishment. Later we compared the breeding bird community of experimentally disturbed plots with that of undisturbed control plots. We discovered that the number of territories (-15.0%) and species richness (-15.2%) in disturbed plots were substantially reduced compared with control plots. Species most affected included those sensitive to human presence (assessed by flight-initiation distances), open-cup nesters and above-ground foragers. Long-distance migrants, however, were unaffected due to their arrival after experimental disturbance took place. These findings highlight how territory establishment is a sensitive period for birds, when even low levels of human recreation may be perceived as threatening, and alter settlement decisions. This can have important implications for the conservation of species, which might go unnoticed when focusing only on already established birds. © 2017 The Author(s).

  16. Shorebird Migration Patterns in Response to Climate Change: A Modeling Approach

    Science.gov (United States)

    Smith, James A.

    2010-01-01

    The availability of satellite remote sensing observations at multiple spatial and temporal scales, coupled with advances in climate modeling and information technologies offer new opportunities for the application of mechanistic models to predict how continental scale bird migration patterns may change in response to environmental change. In earlier studies, we explored the phenotypic plasticity of a migratory population of Pectoral sandpipers by simulating the movement patterns of an ensemble of 10,000 individual birds in response to changes in stopover locations as an indicator of the impacts of wetland loss and inter-annual variability on the fitness of migratory shorebirds. We used an individual based, biophysical migration model, driven by remotely sensed land surface data, climate data, and biological field data. Mean stop-over durations and stop-over frequency with latitude predicted from our model for nominal cases were consistent with results reported in the literature and available field data. In this study, we take advantage of new computing capabilities enabled by recent GP-GPU computing paradigms and commodity hardware (general purchase computing on graphics processing units). Several aspects of our individual based (agent modeling) approach lend themselves well to GP-GPU computing. We have been able to allocate compute-intensive tasks to the graphics processing units, and now simulate ensembles of 400,000 birds at varying spatial resolutions along the central North American flyway. We are incorporating additional, species specific, mechanistic processes to better reflect the processes underlying bird phenotypic plasticity responses to different climate change scenarios in the central U.S.

  17. The evolutionary genetics and emergence of avian influenza viruses in wild birds.

    Directory of Open Access Journals (Sweden)

    Vivien G Dugan

    2008-05-01

    Full Text Available We surveyed the genetic diversity among avian influenza virus (AIV in wild birds, comprising 167 complete viral genomes from 14 bird species sampled in four locations across the United States. These isolates represented 29 type A influenza virus hemagglutinin (HA and neuraminidase (NA subtype combinations, with up to 26% of isolates showing evidence of mixed subtype infection. Through a phylogenetic analysis of the largest data set of AIV genomes compiled to date, we were able to document a remarkably high rate of genome reassortment, with no clear pattern of gene segment association and occasional inter-hemisphere gene segment migration and reassortment. From this, we propose that AIV in wild birds forms transient "genome constellations," continually reshuffled by reassortment, in contrast to the spread of a limited number of stable genome constellations that characterizes the evolution of mammalian-adapted influenza A viruses.

  18. Foraging behaviour of pink-footed geese (Anser brachyrhynchus) during spring migration

    DEFF Research Database (Denmark)

    Chudzińska, Magda Ewa

    and their energetic consequences are therefore of great importance to these birds. In this thesis, I have aimed to address some aspects of the foraging decisions and behaviour of pink-footed geese during their spring migration to the Arctic breeding area. I combined field techniques with telemetry technology as well...... as modelling tools to address questions about how geese forage and fuel during their spring migration. The first three presented manuscripts focus on changes in goose foraging behaviour and energetics over the course of the day, a stopover season and the entire migration. They also focus on variety of factors...... the question: which foraging decision do geese make at the Mid-Norway stopover site....

  19. The Bird.

    Science.gov (United States)

    Hannon, Jean

    2001-01-01

    Students use a dead bird to learn about bird life, anatomy, and death. Students examine a bird body and discuss what happened to the bird. Uses outdoor education as a resource for learning about animals. (SAH)

  20. Comparative analysis of vestibular ecomorphology in birds.

    Science.gov (United States)

    Benson, Roger B J; Starmer-Jones, Ethan; Close, Roger A; Walsh, Stig A

    2017-12-01

    mammals. Furthermore, we find little support for relationships between labyrinth shape and flying style or wing kinematics. Overall, our results suggest that the topological problem of fitting long semicircular canals into a spatially constrained braincase is more important in determining the shape of the avian labyrinth than the specifics of locomotory style or agility. Our results tentatively indicate a link between visual acuity and proportional size of the labyrinth among birds. This suggests that the large labyrinths of birds compared with other tetrapods may result from their generally high visual acuities, and not directly from their ability to fly. The endosseous labyrinths of extinct birds and their close dinosaurian relatives may allow broad inferences about flight or vision, but so far provide few specific insights into detailed aspects of locomotion. © 2017 Anatomical Society.

  1. High-Speed Surface Reconstruction of Flying Birds Using Structured Light

    Science.gov (United States)

    Deetjen, Marc; Lentink, David

    2017-11-01

    Birds fly effectively through complex environments, and in order to understand the strategies that enable them to do so, we need to determine the shape and movement of their wings. Previous studies show that even small perturbations in wing shape have dramatic aerodynamic effects, but these shape changes have not been quantified automatically at high temporal and spatial resolutions. Hence, we developed a custom 3D surface mapping method which uses a high-speed camera to view a grid of stripes projected onto a flying bird. Because the light is binary rather than grayscale, and each frame is separately analyzed, this method can function at any frame rate with sufficient light. The method is automated, non-invasive, and able to measure a volume by simultaneously reconstructing from multiple views. We use this technique to reconstruct the 3D shape of the surface of a parrotlet during flapping flight at 3200 fps. We then analyze key dynamic parameters such as wing twist and angle of attack, and compute aerodynamic parameters such as lift and drag. While this novel system is designed to quantify bird wing shape and motion, it is adaptable for tracking other objects such as quickly deforming fish, especially those which are difficult to reconstruct using other 3D tracking methods. The presenter needs to leave by 3 pm on the final day of the conference (11/21) in order to make his flight. Please account for this in the scheduling if possible by scheduling the presentation earlier in the day or a different day.

  2. Spillover of Newcastle disease viruses from poultry to wild birds in Guangdong province, southern China.

    Science.gov (United States)

    Xiang, Bin; Han, Lujie; Gao, Pei; You, Renrong; Wang, Fumin; Xiao, Jiajie; Liao, Ming; Kang, Yinfeng; Ren, Tao

    2017-11-01

    Despite intensive vaccination programs in many countries, including China, Newcastle disease has been reported sporadically and is still a significant threat to the poultry industry in China. Newcastle disease virus (NDV) is infectious for at least 250 bird species, but the role of wild birds in virus epidemiology remains largely unknown. Fourteen NDV isolates were obtained from 2040 samples collected from wild birds or the environment in Guangdong province, southern China, from 2013 to 2015. The isolation rate was the highest in the period of wintering and lowest during the periods of spring migration, nesting, and postnesting. A maximum clade credibility phylogenetic analysis revealed that at least four genotypes circulate in southern China: three class II genotypes (II, VI, and IX) and one class I (1b). We also demonstrated that most isolates from wild birds were highly similar to isolates from poultry, and two isolates were linked to viruses from wild birds in northern China. These data suggested that wild birds could disseminate NDV and poultry-derived viruses may spillover to wild birds. Accordingly, vaccine development and poultry management strategies should be considered to prevent future NDV outbreaks, particularly given the strength of the poultry industry in developing countries, such as China. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Divergence of Borrelia burgdorferi sensu lato spirochetes could be driven by the host: diversity of Borrelia strains isolated from ticks feeding on a single bird

    Czech Academy of Sciences Publication Activity Database

    Rudenko, Natalia; Golovchenko, Maryna; Belfiore, N. M.; Grubhoffer, Libor; Oliver, J. H., Jr.

    2014-01-01

    Roč. 7, JAN 2014 (2014), s. 4 ISSN 1756-3305 Institutional support: RVO:60077344 Keywords : Borrelia burgdorferi sensu lato * Ixodes minor * bird migration * bird reservoir host * multilocus sequence analysis * multilocus sequence typing * recombinant genotypes * Southeastern United States Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.430, year: 2014

  4. Organochlorine pollutants and stable isotopes in resident and migrant passerine birds from northwest Michoacán, Mexico.

    Science.gov (United States)

    Mora, Miguel A

    2008-10-01

    Although concentrations of organochlorine compounds (OCs) in birds from most of the United States and Canada have decreased over the last 30 years, there is still concern that migrant birds might be exposed to elevated concentrations of OCs during migration in Latin America. The Lerma-Chapala Basin in west-central Mexico is an important migration corridor and wintering area for many species. The objectives of this study were to assess if resident and migrant birds wintering in western Michoacán, Mexico accumulated elevated concentrations of OCs during fall and spring and to determine if the stable isotopes delta(15)N, delta(13)C, and deltaD could be used to predict burdens and origins of DDE accumulation. Resident and migrant passerine insectivorous birds were collected during fall and spring (2001-2002) in northwest Michoacán, near Chapala Lake, Mexico. The carcasses were analyzed for OCs and tail feathers were analyzed for stable isotopes delta(15)N, delta(13)C, and deltaD. The OCs detected in more than 50% of the samples were: oxychlordane (79%), p,p'-DDE (100%), p,p'-DDT (57%), and total PCBs (100%). p,p'-DDE was the OC detected at the highest concentrations, whereas residues of other OCs were near or below detection limits. Overall, there were no significant differences in concentrations of OCs between seasons or between resident and migrant birds. Concentrations of DDE and oxychlordane were somewhat higher in migrant and resident birds during spring than in fall; however, concentrations were significantly different only for oxychlordane. Two resident birds collected in fall and spring had DDE residues >10 microg/g wet weight in carcass. There were no significant differences in delta(13)C and delta(15)N values among species, between seasons, or between migrant and resident birds. However, deltaD values were clearly different between species and helped differentiate migrant from resident birds. deltaD values also were negatively and significantly correlated

  5. 2014-2016 Avian Point Count and Migration Surveys at Site 300 for the Lawrence Livermore National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Fratanduono, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-04-14

    The primary goals of the surveys were to: 1) collect minutes of bird activity within Site 300, 2) consider relative abundance of the different bird species occurring within the Site, 3) collect behavioral information, and 4) provide compelling evidence to determine the status of the Site as a migration corridor or migration stopover site. To this end, two survey types were conducted: avian point counts were conducted on a monthly basis from February 2014 through January 2016 and migration surveys were conducted over two three-month periods from September 2014 through November 2014, and September 2015 through November 2015. These two surveys types provided the opportunity to observe avian species in a variety of conditions across a two year period. Whenever possible or relevant, the observations of either survey were used to inform and complement the observations of the other survey in pursuit of the above goals. Both survey types are described below.

  6. Coastal Resources Atlas: Long Island: BIRDS (Bird Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for wading birds, shorebirds, waterfowl, raptors, diving birds, seabirds, passerine birds, and gulls and...

  7. Poor flight performance in deep-diving cormorants.

    Science.gov (United States)

    Watanabe, Yuuki Y; Takahashi, Akinori; Sato, Katsufumi; Viviant, Morgane; Bost, Charles-André

    2011-02-01

    Aerial flight and breath-hold diving present conflicting morphological and physiological demands, and hence diving seabirds capable of flight are expected to face evolutionary trade-offs regarding locomotory performances. We tested whether Kerguelen shags Phalacrocorax verrucosus, which are remarkable divers, have poor flight capability using newly developed tags that recorded their flight air speed (the first direct measurement for wild birds) with propeller sensors, flight duration, GPS position and depth during foraging trips. Flight air speed (mean 12.7 m s(-1)) was close to the speed that minimizes power requirement, rather than energy expenditure per distance, when existing aerodynamic models were applied. Flights were short (mean 92 s), with a mean summed duration of only 24 min day(-1). Shags sometimes stayed at the sea surface without diving between flights, even on the way back to the colony, and surface durations increased with the preceding flight durations; these observations suggest that shags rested after flights. Our results indicate that their flight performance is physiologically limited, presumably compromised by their great diving capability (max. depth 94 m, duration 306 s) through their morphological adaptations for diving, including large body mass (enabling a large oxygen store), small flight muscles (to allow for large leg muscles for underwater propulsion) and short wings (to decrease air volume in the feathers and hence buoyancy). The compromise between flight and diving, as well as the local bathymetry, shape the three-dimensional foraging range (<26 km horizontally, <94 m vertically) in this bottom-feeding cormorant.

  8. Migration confers survival benefits against avian predators for partially migratory freshwater fish

    DEFF Research Database (Denmark)

    Skov, Christian; Chapman, Ben B.; Baktoft, Henrik

    2013-01-01

    The importance of predation risk in shaping patterns of animal migration is not well studied, mostly owing to difficulties in accurately quantifying predation risk for migratory versus resident individuals. Here, we present data from an extensive field study, which shows that migration...... in a freshwater fish (roach, Rutilus rutilus) that commonly migrates from lakes to streams during winter confers a significant survival benefit with respect to bird (cormorant, Phalacrocorax carbo spp.) predation. We tagged over 2000 individual fish in two Scandinavian lakes over 4 years and monitored migratory...... behaviour using passive telemetry. Next, we calculated the predation vulnerability of fish with differing migration strategies, by recovering data from passive integrated transponder tags of fish eaten by cormorants at communal roosts close to the lakes. We show that fish can reduce their predation risk...

  9. Incorporating Partners in Flight Priorities into State Agency Operational Plans: Development of a Management System for Wetland Passerines

    Science.gov (United States)

    Thomas P. Hodgman

    2005-01-01

    State agencies are often considered the prime avenues for implementation of Partners in Flight (PIF) bird conservation plans. Yet, such agencies already have in place a planning structure, which allows for dispersal of Federal Aid funds and guides management actions. Consequently, superimposing additional planning frameworks (e.g., PIF bird conservation plans) on state...

  10. Improved supervised classification of accelerometry data to distinguish behaviors of soaring birds

    Science.gov (United States)

    Suffredini, Tony; Wessells, Stephen M.; Bloom, Peter H.; Lanzone, Michael; Blackshire, Sheldon; Sridhar, Srisarguru; Katzner, Todd

    2017-01-01

    Soaring birds can balance the energetic costs of movement by switching between flapping, soaring and gliding flight. Accelerometers can allow quantification of flight behavior and thus a context to interpret these energetic costs. However, models to interpret accelerometry data are still being developed, rarely trained with supervised datasets, and difficult to apply. We collected accelerometry data at 140Hz from a trained golden eagle (Aquila chrysaetos) whose flight we recorded with video that we used to characterize behavior. We applied two forms of supervised classifications, random forest (RF) models and K-nearest neighbor (KNN) models. The KNN model was substantially easier to implement than the RF approach but both were highly accurate in classifying basic behaviors such as flapping (85.5% and 83.6% accurate, respectively), soaring (92.8% and 87.6%) and sitting (84.1% and 88.9%) with overall accuracies of 86.6% and 92.3% respectively. More detailed classification schemes, with specific behaviors such as banking and straight flights were well classified only by the KNN model (91.24% accurate; RF = 61.64% accurate). The RF model maintained its accuracy of classifying basic behavior classification accuracy of basic behaviors at sampling frequencies as low as 10Hz, the KNN at sampling frequencies as low as 20Hz. Classification of accelerometer data collected from free ranging birds demonstrated a strong dependence of predicted behavior on the type of classification model used. Our analyses demonstrate the consequence of different approaches to classification of accelerometry data, the potential to optimize classification algorithms with validated flight behaviors to improve classification accuracy, ideal sampling frequencies for different classification algorithms, and a number of ways to improve commonly used analytical techniques and best practices for classification of accelerometry data. PMID:28403159

  11. Blood lead levels for Eurasian black vultures (Aegypius monachus migrating between Mongolia and the Republic of Korea

    Directory of Open Access Journals (Sweden)

    David Kenny

    2015-09-01

    Full Text Available Since 2009, we have been determining blood lead levels (BLLs for Eurasian black vulture (EbVs, Aegypius monachus in Mongolia. Since EbVs migrated from Mongolia to the Republic (R. of Korea in 2012, we started comparing BLLs from Mongolia to Korean birds [Mongolia; mean=2.72±0.09 μg/dL standard error (SE, n=181, R. of Korea; mean=6.68±0.58 μg/dL SE, n=124]. In Korea we also analyzed birds by comparing BLLs for free-ranging birds (mean=7.54±0.50 μg/dL SE, n=44 to rehabilitation center birds (mean=6.21±0.86 μg/dL SE, n=80, and for birds fed rescued water deer (Hydropotes inermis (mean=11.26±1.66 μg/dL SE, n=7 to birds fed livestock (mean=1.97±0.27 μg/dL, n=4. Finally, we analyzed BLLs from Mongolia and the R. of Korea according to the following categories: background=<10.0 μg/dL (Mongolia 100%, n=181; R. of Korea 83.1%, exposure=≥10.0 μg/dL to <45.0 μg/dL (Mongolia 0%; R. of Korea 16.1%, n=20, and diagnostic=≥45.0 μg/dL (Mongolia 0%; R. of Korea 0.8%, n=1. Our research indicates that EbVs are acquiring lead while migrating to the R. of Korea.

  12. Vertebrate fauna of the Roman period, migrations period and Medieval period in Vojvodina (Serbia

    Directory of Open Access Journals (Sweden)

    Radmanović Darko P.

    2014-01-01

    Full Text Available Based on current published and unpublished research results, a total of 16 vertebrate species members of mammal (Mammalia, bird (Aves and osteichthyes (Osteichthyes classes have been registered at 11 archaeological sites from the Roman Period in Vojvodina. Mammals dominate with 12 species and one genus, birds are present with 3 species, and osteichthyes with one. From the Migration Period, at 9 sites, 22 vertebrate species have been registered, of which 13 species and one genus of mammals, 4 species and one genus of birds, and 5 species from the Osteichthyes class. At 8 sites from the Medieval Period, 16 vertebrate species have been registered. Mammals are the most numerous class with 10 species and one genus, while birds are present with 4 species and one genus. Furthermore, two species of osteichthyes have also been registered.

  13. Current and Future Flight Operating Systems

    Science.gov (United States)

    Cudmore, Alan

    2007-01-01

    This viewgraph presentation reviews the current real time operating system (RTOS) type in use with current flight systems. A new RTOS model is described, i.e. the process model. Included is a review of the challenges of migrating from the classic RTOS to the Process Model type.

  14. Respiratory and reproductive paleophysiology of dinosaurs and early birds.

    Science.gov (United States)

    Ruben, John A; Jones, Terry D; Geist, Nicholas R

    2003-01-01

    In terms of their diversity and longevity, dinosaurs and birds were/are surely among the most successful of terrestrial vertebrates. Unfortunately, interpreting many aspects of the biology of dinosaurs and the earliest of the birds presents formidable challenges because they are known only from fossils. Nevertheless, a variety of attributes of these taxa can be inferred by identification of shared anatomical structures whose presence is causally linked to specialized functions in living reptiles, birds, and mammals. Studies such as these demonstrate that although dinosaurs and early birds were likely to have been homeothermic, the absence of nasal respiratory turbinates in these animals indicates that they were likely to have maintained reptile-like (ectothermic) metabolic rates during periods of rest or routine activity. Nevertheless, given the metabolic capacities of some extant reptiles during periods of elevated activity, early birds were probably capable of powered flight. Similarly, had, for example, theropod dinosaurs possessed aerobic metabolic capacities and habits equivalent to those of some large, modern tropical latitude lizards (e.g., Varanus), they may well have maintained significant home ranges and actively pursued and killed large prey. Additionally, this scenario of active, although ectothermic, theropod dinosaurs seems reinforced by the likely utilization of crocodilian-like, diaphragm breathing in this group. Finally, persistent in vivo burial of their nests and apparent lack of egg turning suggests that clutch incubation by dinosaurs was more reptile- than birdlike. Contrary to previous suggestions, there is little if any reliable evidence that some dinosaur young may have been helpless and nestbound (altricial) at hatching.

  15. Migration strategies of Swan Geese Anser cygnoides from northeast Mongolia

    Science.gov (United States)

    Batbayar, Nyambayar; Takekawa, John Y.; Newman, Scott H.; Prosser, Diann J.; Natsagdorj, Tseveenmyadag; Xiao, Xiangming

    2011-01-01

    In 2006–2008, 25 Swan Geese Anser cygnoides were marked with solar-powered GPS satellite transmitters in northeast Mongolia to examine the timing and pathways of their migration. Most geese began their autumn migration in August, flying southeast toward a staging area at the Yalu River Estuary on the China-North Korea border. After staging for several weeks, the Swan Geese continued to their wintering grounds at wetlands along the Yangtze River Basin of eastern China in December. Spring migration commenced in late February, and the birds following either a same-route or loop migration to arrive at the breeding grounds in mid April. Swan Geese used a larger number of staging areas for a longer duration when they were north of 42°N latitude; they seemed to avoid staging for extended periods in the highly urbanised areas of eastern China. Further research should examine threats and disturbances to the geese in relation to human population growth and increasing urbanisation.

  16. The dynamics of fauna and population of birds in agricultural landscapes on the border of Kazan International Airport

    Science.gov (United States)

    Bespalov, A. F.; Belyaev, A. N.

    2018-01-01

    The dynamics of fauna and population of birds from agricultural lands near Kazan International Airport has been studied for one year. A total of 60 bird species have been registered, of which 26 species must be considered as highly dangerous to flying aircraft. With regard to seasonal activity, the nesting period (April - June) is the most hazardous, since it is characterized by maximum species richness and total population density of birds, as well as their high species diversity. Furthermore, a serious danger is posed by the period of postnesting nomadic movements and the onset of migrations (July - September) when the species diversity turns out to be the highest and the total population density begins to decrease. It has been recommended based on the obtained results that the current crops should be replaced by cultivars that will be less attractive to birds. In spring and autumn, certain bird hazing and frightening measures must be taken on a more regular basis.

  17. Conference on wind turbines impact on birds and bats

    International Nuclear Information System (INIS)

    Ratzbor, Guenter; Dubourg-Savage, Marie-Jo; Andre, Yann; Kirchstetter, France; Bungart, Rolf; Neau, Paul; Gruendonner, Dieter; Lagrange, Hubert; Rufray, Vincent; Prie, Vincent; Haquart, Alexandre; Melki, Frederic; Fonio, Joseph; Brinkmann, Robert; Hoetker, Hermann; Grajetzki, Bodo; Mammen, Ubbo; Fagot, Guillaume; Hill, Reinhold

    2008-01-01

    The French-German office for Renewable energies (OFAEnR) organised a conference on wind turbines impacts on birds and bats. In the framework of this French-German exchange of experience, more than 85 participants exchanged views on the impacts of wind energy development on birds and bats mortality, the legal aspects, the research programs and the remedial actions. This document brings together the available presentations (slides) made during this event: 1 - Wind energy and nature protection - Is there really a conflict? (Guenter Ratzbor); 2 - Taking bats into account in wind energy projects in the European legal framework (Marie-Jo Dubourg-Savage); 3 - Wind energy-biodiversity national program - Towards a biodiversity label for wind farms (Yann Andre); 4 - Development, construction and operation of a bats-friendly wind farm in France? (France Kirchstetter); 5 - Practical experience of bats protection rules in the framework of German wind energy projects - Examples taken from projects development (Rolf Bungart); 6 - Inclusion of birds and bats issues in wind energy planning documents: schemes and wind energy development area (Paul Neau); 7 - Inclusion of potential threats for birds and bats in the definition of wind energy exploitation areas in Germany (Dieter Gruendonner); 8 - Chirotech - Conciliation between wind energy development and bats preservation - Data collection status, first results and perspectives (Hubert Lagrange, Joseph Fonio); 9 - Bats and wind energy in Germany - Present day situation and research works for conflicts resolution (Robert Brinkmann); 10 - Wind turbines and raptors in Germany: experience gained and presentation of a new research project (Hermann Hoetker); 11 - Birds fauna analysis in the framework of the development of the Cote d'Albatre offshore wind energy project (Guillaume Fagot); 12 - Birds flight remote study methods around FINO 1 (Reinhold Hill)

  18. Detailed description of the Ócsa Bird Ringing Station, Hungary

    OpenAIRE

    Csörgő Tibor; Harnos Andrea; Rózsa Lajos; Karcza Zsolt; Fehérvári Péter

    2016-01-01

    The present paper acts as an introduction to a series that will describe the exploratory analyses of migration phenology and morphometrics of the most common passerine species at the Ócsa Bird Ringing Station. This station is situated in the Ócsa Landscape Protection Area that belongs to the Duna–Ipoly National Park, Hungary. The area is somewhat cooler and more humid than the surrounding agricultural fields and tree plantations, covered by a mosaic of diverse hygrophilous vegetation patches....

  19. FLightR : An R package for reconstructing animal paths from solar geolocation loggers

    NARCIS (Netherlands)

    Rakhimberdiev, Eldar; Saveliev, Anatoly; Piersma, Theunis; Karagicheva, Julia

    Solar geolocators are relatively cheap and simple tools which are widely used to study the migration of animals, especially birds. The methods to estimate the geographic positions from the light-intensity patterns collected by these loggers, however, are still under development. The accurate

  20. FLightR : An R package for reconstructing animal paths from solar geolocation loggers

    NARCIS (Netherlands)

    Rakhimberdiev, Eldar; Saveliev, Anatoly; Piersma, Theunis; Karagicheva, Julia

    2017-01-01

    Solar geolocators are relatively cheap and simple tools which are widely used to study the migration of animals, especially birds. The methods to estimate the geographic positions from the light-intensity patterns collected by these loggers, however, are still under development. The accurate

  1. Using the power of comparison to explain habitat use and migration strategies of shorebirds worldwide

    NARCIS (Netherlands)

    Piersma, Theunis; Bairlein, F.

    2007-01-01

    Shorebirds, or waders, form an ecologically (but not phylogenetically) homogenous group of birds that, despite this homogeneity, exhibits clear correlated contrasts in habitat use and migration distance between closely related species pairs. In addition, within species there is distinct variation in

  2. Hovering and forward flight energetics in Anna's and Allen's hummingbirds.

    Science.gov (United States)

    Clark, Christopher James; Dudley, Robert

    2010-01-01

    Aerodynamic theory predicts that the mechanical costs of flight are lowest at intermediate flight speeds; metabolic costs of flight should trend similarly if muscle efficiency is constant. We measured metabolic rates for nine Anna's hummingbirds (Calypte anna) and two male Allen's hummingbirds (Selasphorus sasin) feeding during flight from a free-standing mask over a range of airspeeds. Ten of 11 birds exhibited higher metabolic costs during hovering than during flight at intermediate airspeeds, whereas one individual exhibited comparable costs at hovering and during forward flight up to speeds of approximately 7 m s(-1). Flight costs of all hummingbirds increased at higher airspeeds. Relative to Anna's hummingbirds, Allen's hummingbirds exhibited deeper minima in the power curve, possibly due to higher wing loadings and greater associated costs of induced drag. Although feeding at a mask in an airstream may reduce body drag and, thus, the contributions of parasite power to overall metabolic expenditure, these results suggest that hummingbird power curves are characterized by energetic minima at intermediate speeds relative to hovering costs.

  3. Avian influenza survey in migrating waterfowl in Sonora, Mexico.

    Science.gov (United States)

    Montalvo-Corral, M; López-Robles, G; Hernández, J

    2011-02-01

    A two-year survey was carried out on the occurrence of avian influenza in migrating birds in two estuaries of the Mexican state of Sonora, which is located within the Pacific flyway. Cloacal and oropharyngeal swabs were collected from 1262 birds, including 20 aquatic bird species from the Moroncarit and Tobari estuaries in Sonora, Mexico. Samples were tested for type A influenza (M), H5 Eurasian and North American subtypes (H5EA and H5NA respectively) and the H7 North American subtype (H7NA). Gene detection was determined by one-step real-time reverse transcription polymerase chain reaction (RRT-PCR). The results revealed that neither the highly pathogenic avian influenza virus H5 of Eurasian lineage nor H7NA were detected. The overall prevalence of avian influenza type A (M-positive) in the sampled birds was 3.6% with the vast majority in dabbling ducks (Anas species). Samples from two birds, one from a Redhead (Aythya americana) and another from a Northern Shoveler (Anas clypeata), were positive for the low-pathogenic H5 avian influenza virus of North American lineage. These findings represented documented evidence of the occurrence of avian influenza in wintering birds in the Mexican wetlands. This type of study contributes to the understanding of how viruses spread to new regions of North America and highlights the importance of surveillance for the early detection and control of potentially pathogenic strains, which could affect animal and human health. © 2010 Blackwell Verlag GmbH.

  4. Assessing the impact of marine wind farms on birds through movement modelling.

    Science.gov (United States)

    Masden, Elizabeth A; Reeve, Richard; Desholm, Mark; Fox, Anthony D; Furness, Robert W; Haydon, Daniel T

    2012-09-07

    Advances in technology and engineering, along with European Union renewable energy targets, have stimulated a rapid growth of the wind power sector. Wind farms contribute to carbon emission reductions, but there is a need to ensure that these structures do not adversely impact the populations that interact with them, particularly birds. We developed movement models based on observed avoidance responses of common eider Somateria mollissima to wind farms to predict, and identify potential measures to reduce, impacts. Flight trajectory data that were collected post-construction of the Danish Nysted offshore wind farm were used to parameterize competing models of bird movements around turbines. The model most closely fitting the observed data incorporated individual variation in the minimum distance at which birds responded to the turbines. We show how such models can contribute to the spatial planning of wind farms by assessing their extent, turbine spacing and configurations on the probability of birds passing between the turbines. Avian movement models can make new contributions to environmental assessments of wind farm developments, and provide insights into how to reduce impacts that can be identified at the planning stage.

  5. Visual guidance of forward flight in hummingbirds reveals control based on image features instead of pattern velocity.

    Science.gov (United States)

    Dakin, Roslyn; Fellows, Tyee K; Altshuler, Douglas L

    2016-08-02

    Information about self-motion and obstacles in the environment is encoded by optic flow, the movement of images on the eye. Decades of research have revealed that flying insects control speed, altitude, and trajectory by a simple strategy of maintaining or balancing the translational velocity of images on the eyes, known as pattern velocity. It has been proposed that birds may use a similar algorithm but this hypothesis has not been tested directly. We examined the influence of pattern velocity on avian flight by manipulating the motion of patterns on the walls of a tunnel traversed by Anna's hummingbirds. Contrary to prediction, we found that lateral course control is not based on regulating nasal-to-temporal pattern velocity. Instead, birds closely monitored feature height in the vertical axis, and steered away from taller features even in the absence of nasal-to-temporal pattern velocity cues. For vertical course control, we observed that birds adjusted their flight altitude in response to upward motion of the horizontal plane, which simulates vertical descent. Collectively, our results suggest that birds avoid collisions using visual cues in the vertical axis. Specifically, we propose that birds monitor the vertical extent of features in the lateral visual field to assess distances to the side, and vertical pattern velocity to avoid collisions with the ground. These distinct strategies may derive from greater need to avoid collisions in birds, compared with small insects.

  6. FLightR: an r package for reconstructing animal paths from solar geolocation loggers

    NARCIS (Netherlands)

    Rakhimberdiev, E.; Saveliev, A.; Piersma, T.; Karagicheva, J.

    2017-01-01

    1. Solar geolocators are relatively cheap and simple tools which are widely used to study the migration of animals,especially birds. The methods to estimate the geographic positions from the light-intensity patterns collectedby these loggers, however, are still under development.2. The accurate

  7. White Flight from School Desegregation: Magnitude, Sources, and Policy Options. Final Report.

    Science.gov (United States)

    Rossell, Christine H.; Hawley, Willis D.

    Discussed in this report are the extent and causes of white flight from school desegregation and policy options for controlling it. After an introductory section, the report considers the extent of white flight from desegregating schools, taking into account the effects of suburbanization, interregional migration, and differentials in…

  8. Highly Pathogenic Avian Influenza Virus among Wild Birds in Mongolia

    Science.gov (United States)

    Gilbert, Martin; Jambal, Losolmaa; Karesh, William B.; Fine, Amanda; Shiilegdamba, Enkhtuvshin; Dulam, Purevtseren; Sodnomdarjaa, Ruuragchaa; Ganzorig, Khuukhenbaatar; Batchuluun, Damdinjav; Tseveenmyadag, Natsagdorj; Bolortuya, Purevsuren; Cardona, Carol J.; Leung, Connie Y. H.; Peiris, J. S. Malik; Spackman, Erica; Swayne, David E.; Joly, Damien O.

    2012-01-01

    Mongolia combines a near absence of domestic poultry, with an abundance of migratory waterbirds, to create an ideal location to study the epidemiology of highly pathogenic avian influenza virus (HPAIV) in a purely wild bird system. Here we present the findings of active and passive surveillance for HPAIV subtype H5N1 in Mongolia from 2005–2011, together with the results of five outbreak investigations. In total eight HPAIV outbreaks were confirmed in Mongolia during this period. Of these, one was detected during active surveillance employed by this project, three by active surveillance performed by Mongolian government agencies, and four through passive surveillance. A further three outbreaks were recorded in the neighbouring Tyva Republic of Russia on a lake that bisects the international border. No HPAIV was isolated (cultured) from 7,855 environmental fecal samples (primarily from ducks), or from 2,765 live, clinically healthy birds captured during active surveillance (primarily shelducks, geese and swans), while four HPAIVs were isolated from 141 clinically ill or dead birds located through active surveillance. Two low pathogenic avian influenza viruses (LPAIV) were cultured from ill or dead birds during active surveillance, while environmental feces and live healthy birds yielded 56 and 1 LPAIV respectively. All Mongolian outbreaks occurred in 2005 and 2006 (clade 2.2), or 2009 and 2010 (clade 2.3.2.1); all years in which spring HPAIV outbreaks were reported in Tibet and/or Qinghai provinces in China. The occurrence of outbreaks in areas deficient in domestic poultry is strong evidence that wild birds can carry HPAIV over at least moderate distances. However, failure to detect further outbreaks of clade 2.2 after June 2006, and clade 2.3.2.1 after June 2010 suggests that wild birds migrating to and from Mongolia may not be competent as indefinite reservoirs of HPAIV, or that HPAIV did not reach susceptible populations during our study. PMID:22984464

  9. Base-line investigations of birds in relation to an offshore wind farm at Horns Rev, and results from the year of construction

    Energy Technology Data Exchange (ETDEWEB)

    Kjaer Christensen, T.; Clausager, I.; Krag Petersen, I.

    2003-04-15

    The present report presents the base-line investigations of birds conducted during August 1999-April 2001 in relation to construction of an offshore wind farm at Horns Rev, 14 km west-south-west of Blaevandshuk, in the Danish North Sea. The report also presents data collected during the period September 2001-April 2002, when construction of the wind farm was in progress. The wind farm will consist of 80 wind turbines, each of 2 MW, and cover an area of c. 20 km{sup 2}. The eastern part of the North Sea constitutes major staging and wintering grounds for huge numbers of water- and seabirds. The area is also known to be an important site for migrating birds, which especially in autumn pass in large numbers. As Denmark has obligations to protect and maintain the bird populations it was laid down in the approval for erection of the wind farm that the impact on birds should be investigated. According to the 1% criteria defined in the Ramsar Convention, the eastern part of the North Sea including the wind farm area is of international importance to divers, Common Tern, and Sandwich Tern. A number of other species, e.g. Common Eider, Common Scoter, Guillemot and Razorbill, are present in the area in significant numbers as well, though these numbers do not make up 1% of the populations. Detailed distributions of birds in the area around and at Horns Rev were virtually unknown until initiation of this project. Previous bird counts in this area have been carried out almost exclusively from the coast and detailed knowledge exists concerning the numbers of roosting at and migrating birds from the westernmost point of Jutland, Blaevandshuk. To describe the numbers and distributions of birds staging and wintering in the Horns Rev area, bird investigations were initiated in 1999 by using standardised transect counts from aircraft. Up to April 2002, 18 aerial counts have been carried out over an area of c. 1,700 km{sup 2} centred on the Horns Rev project area. (au)

  10. Base-line investigations of birds in relation to an offshore wind farm at Horns Rev, and results from the year of construction

    International Nuclear Information System (INIS)

    Kjaer Christensen, T.; Clausager, I.; Krag Petersen, I.

    2003-01-01

    The present report presents the base-line investigations of birds conducted during August 1999-April 2001 in relation to construction of an offshore wind farm at Horns Rev, 14 km west-south-west of Blaevandshuk, in the Danish North Sea. The report also presents data collected during the period September 2001-April 2002, when construction of the wind farm was in progress. The wind farm will consist of 80 wind turbines, each of 2 MW, and cover an area of c. 20 km 2 . The eastern part of the North Sea constitutes major staging and wintering grounds for huge numbers of water- and seabirds. The area is also known to be an important site for migrating birds, which especially in autumn pass in large numbers. As Denmark has obligations to protect and maintain the bird populations it was laid down in the approval for erection of the wind farm that the impact on birds should be investigated. According to the 1% criteria defined in the Ramsar Convention, the eastern part of the North Sea including the wind farm area is of international importance to divers, Common Tern, and Sandwich Tern. A number of other species, e.g. Common Eider, Common Scoter, Guillemot and Razorbill, are present in the area in significant numbers as well, though these numbers do not make up 1% of the populations. Detailed distributions of birds in the area around and at Horns Rev were virtually unknown until initiation of this project. Previous bird counts in this area have been carried out almost exclusively from the coast and detailed knowledge exists concerning the numbers of roosting at and migrating birds from the westernmost point of Jutland, Blaevandshuk. To describe the numbers and distributions of birds staging and wintering in the Horns Rev area, bird investigations were initiated in 1999 by using standardised transect counts from aircraft. Up to April 2002, 18 aerial counts have been carried out over an area of c. 1,700 km 2 centred on the Horns Rev project area. (au)

  11. Remotely sensed wind speed predicts soaring behaviour in a wide-ranging pelagic seabird.

    Science.gov (United States)

    Gibb, Rory; Shoji, Akiko; Fayet, Annette L; Perrins, Chris M; Guilford, Tim; Freeman, Robin

    2017-07-01

    Global wind patterns affect flight strategies in many birds, including pelagic seabirds, many of which use wind-powered soaring to reduce energy costs during at-sea foraging trips and migration. Such long-distance movement patterns are underpinned by local interactions between wind conditions and flight behaviour, but these fine-scale relationships are far less well understood. Here we show that remotely sensed ocean wind speed and direction are highly significant predictors of soaring behaviour in a migratory pelagic seabird, the Manx shearwater ( Puffinus puffinus ). We used high-frequency GPS tracking data (10 Hz) and statistical behaviour state classification to identify two energetic modes in at-sea flight, corresponding to flap-like and soar-like flight. We show that soaring is significantly more likely to occur in tailwinds and crosswinds above a wind speed threshold of around 8 m s -1 , suggesting that these conditions enable birds to reduce metabolic costs by preferentially soaring over flapping. Our results suggest a behavioural mechanism by which wind conditions may shape foraging and migration ecology in pelagic seabirds, and thus indicate that shifts in wind patterns driven by climate change could impact this and other species. They also emphasize the emerging potential of high-frequency GPS biologgers to provide detailed quantitative insights into fine-scale flight behaviour in free-living animals. © 2017 The Author(s).

  12. Flight Trajectory Planning for Fixed-Wing Aircraft in Loss of Thrust Emergencies

    OpenAIRE

    Paul, Saswata; Hole, Frederick; Zytek, Alexandra; Varela, Carlos A.

    2017-01-01

    Loss of thrust emergencies-e.g., induced by bird/drone strikes or fuel exhaustion-create the need for dynamic data-driven flight trajectory planning to advise pilots or control UAVs. While total loss of thrust trajectories to nearby airports can be pre-computed for all initial points in a 3D flight plan, dynamic aspects such as partial power and airplane surface damage must be considered for accuracy. In this paper, we propose a new Dynamic Data-Driven Avionics Software (DDDAS) approach which...

  13. Demographic outcomes of diverse migration strategies assessed in a metapopulation of tundra swans.

    Science.gov (United States)

    Ely, Craig R; Meixell, Brandt W

    2016-01-01

    Migration is a prominent aspect of the life history of many avian species, but the demographic consequences of variable migration strategies have only infrequently been investigated, and rarely when using modern technological and analytical methods for assessing survival, movement patterns, and long-term productivity in the context of life history theory. We monitored the fates of 50 satellite-implanted tundra swans (Cygnus columbianus) over 4 years from five disparate breeding areas in Alaska, and used known-fate analyses to estimate monthly survival probability relative to migration distance, breeding area, migratory flyway, breeding status, and age. We specifically tested whether migratory birds face a trade-off, whereby long-distance migrants realize higher survival rates at the cost of lower productivity because of reduced time on breeding areas relative to birds that migrate shorter distances and spend more time on breeding areas. Annual migration distances varied significantly among breeding areas (1020 to 12720 km), and were strongly negatively correlated with time spent on breeding areas (r = -0.986). Estimates of annual survival probability varied by wintering area (Pacific coast, Alaska Peninsula, and Eastern seaboard) and ranged from 0.79 (95%CI: 0.70-0.88) to 1.0, depending on criteria used to discern mortalities from radio failures. We did not find evidence for a linear relationship between migration distance and survival as swans from the breeding areas with the shortest and longest migration distances had the highest survival probabilities. Survival was lower in the first year post-marking than in subsequent years, but there was not support for seasonal differences in survival. Productivity varied among breeding populations and was generally inversely correlated to survival, but not migration distance or time spent on breeding areas. Tundra swans conformed to a major tenet of life history theory, as populations with the highest survival

  14. Longer wings for faster springs - wing length relates to spring phenology in a long-distance migrant across its range.

    Science.gov (United States)

    Hahn, Steffen; Korner-Nievergelt, Fränzi; Emmenegger, Tamara; Amrhein, Valentin; Csörgő, Tibor; Gursoy, Arzu; Ilieva, Mihaela; Kverek, Pavel; Pérez-Tris, Javier; Pirrello, Simone; Zehtindjiev, Pavel; Salewski, Volker

    2016-01-01

    In migratory birds, morphological adaptations for efficient migratory flight often oppose morphological adaptations for efficient behavior during resident periods. This includes adaptations in wing shape for either flying long distances or foraging in the vegetation and in climate-driven variation of body size. In addition, the timing of migratory flights and particularly the timely arrival at local breeding sites is crucial because fitness prospects depend on site-specific phenology. Thus, adaptations for efficient long-distance flights might be also related to conditions at destination areas. For an obligatory long-distance migrant, the common nightingale, we verified that wing length as the aerodynamically important trait, but not structural body size increased from the western to the eastern parts of the species range. In contrast with expectation from aerodynamic theory, however, wing length did not increase with increasing migration distances. Instead, wing length was associated with the phenology at breeding destinations, namely the speed of local spring green-up. We argue that longer wings are beneficial for adjusting migration speed to local conditions for birds breeding in habitats with fast spring green-up and thus short optimal arrival periods. We suggest that the speed of spring green-up at breeding sites is a fundamental variable determining the timing of migration that fine tune phenotypes in migrants across their range.

  15. Investigations of the migrating motor complex in domestic turkeys.

    Science.gov (United States)

    Mueller, L R; Duke, G E; Evanson, O A

    1990-09-01

    The motor correlate of the migrating myoelectric complex (MMC) was characterized in domestic turkeys, and feeding state, age, sex, and time of day were examined as possible factors influencing the motor activity observed. Strain gauge transducers, and in a few birds Ag-AgCl bipolar electrodes, were implanted on the caudoventral thin muscle of the muscular stomach, the duodenum, ileum, cecum, and colon. Contractility was recorded for 8-10 h per bird on alternating days for 2-3 wk, except in birds involved in four 24-h recording sessions during a 2-wk period. Intense motor activity characteristic of phase III of the MMC occurred only in the ileum; other phases could not be identified. The duration, propagation velocity, and percent of cyclic motor patterns propagating from one site to another were similar to those reported in other galliform species. The occurrence of cyclic motor activity appeared to be related to food consumption; the number of motor patterns occurring during an intense feeding session was less than the number observed 1.5-2 h after feeding. In addition, more motor patterns were recorded in fasted poults during the light period than in the dark; however, the reverse was observed in juveniles fed ad libitum. Cyclic motor activity recorded in fasted 18-wk-old birds was of longer duration than that in fasted 8-wk-old birds. No statistically significant differences were noted in the cyclic motor patterns of male vs. female poults.

  16. Bird interactions with offshore oil and gas platforms: review of impacts and monitoring techniques.

    Science.gov (United States)

    Ronconi, Robert A; Allard, Karel A; Taylor, Philip D

    2015-01-01

    Thousands of oil and gas platforms are currently operating in offshore waters globally, and this industry is expected to expand in coming decades. Although the potential environmental impacts of offshore oil and gas activities are widely recognized, there is limited understanding of their impacts on migratory and resident birds. A literature review identified 24 studies and reports of bird-platform interactions, most being qualitative and half having been peer-reviewed. The most frequently observed effect, for seabirds and landbirds, is attraction and sometimes collisions associated with lights and flares; episodic events have caused the deaths of hundreds or even thousands of birds. Though typically unpredictable, anecdotally, it is known that poor weather, such as fog, precipitation and low cloud cover, can exacerbate the effect of nocturnal attraction to lights, especially when coincidental with bird migrations. Other effects include provision of foraging and roosting opportunities, increased exposure to oil and hazardous environments, increased exposure to predators, or repulsion from feeding sites. Current approaches to monitoring birds at offshore platforms have focused on observer-based methods which can offer species-level bird identification, quantify seasonal patterns of relative abundance and distribution, and document avian mortality events and underlying factors. Observer-based monitoring is time-intensive, limited in spatial and temporal coverage, and suffers without clear protocols and when not conducted by trained, independent observers. These difficulties are exacerbated because deleterious bird-platform interaction is episodic and likely requires the coincidence of multiple factors (e.g., darkness, cloud, fog, rain conditions, occurrence of birds in vicinity). Collectively, these considerations suggest a need to implement supplemental systems for monitoring bird activities around offshore platforms. Instrument-based approaches, such as radar

  17. Changes in bird community composition in response to growth changes in short-rotation woody crop planting

    International Nuclear Information System (INIS)

    Tolbert, V.R.; Hanowski, J.; Schiller, A.; Hoffman, W.; Christian, D.; Lindberg, J.

    1997-01-01

    Hybrid poplar established as intensively managed short-rotation woody crops (SRWC) on former agricultural lands can provide habitat for wildlife. Studies of bird use of SRWC for nesting and during fall migration have shown that the numbers and kinds of breeding birds using mature plantings of hybrid poplar are similar to natural forested lands. In Minnesota, the number of species of breeding birds using habitat provided by clonal-trial plantings and young larger-scale plantings (12-64 ha) of hybrid poplar were initially most similar to those using grasslands and row-crops. As the plantings approached canopy closure, successional species became predominant. In the Pacific Northwest, breeding bird composition and density were very similar for mature plantings and forested areas; however, fall migrants were found primarily in forested areas. In the Southeast, preliminary comparisons of breeding bird use of plantings of sweetgum and sycamore with naturally regenerating forests of different ages and sizes and vegetation structure are showing no size effect on use. As with hybrid poplar, species use of the more mature plantings of sweetgum and sycamore was most similar to that of natural forests. (author)

  18. Malfunction Rates of Bird Flight Diverters on Powerlines in the Mongolian Gobi

    Directory of Open Access Journals (Sweden)

    Batsuuri Dashnyam

    2016-11-01

    Full Text Available The Oyu Tolgoi (OT project, one of the world’s largest copper and gold mines, is located in Gobi Desert of Mongolia. To help meet its target of Net Positive Impact on key biodiversity features such as the Houbara bustard (Chlamydotis undulata the OT installed bird fl ight diverters (BFDs include spiral and fl apper devices to its power transmission lines to reduce the risk of birds hitting the wires. Despite the many studies demonstrating that BFDs reduce collision rates, we could fi nd no published information on malfunction rates of BFDs. In January 2013, we surveyed the physical function of 1,200 BFDs (e.g. 600 fl appers and 600 spirals in three sample areas on each of four lines of varying voltage and structure. Of the 600 fl appers examined, 123 had malfunctioned within nine months of installation, while the malfunction rate of the 600 spirals studied was zero. Using a Generalized Linear Mixed Model, we found that the rate of fl apper malfunction increased with decreasing fl apper size and power line diameter. Further, the fl apper malfunction rate increased as the distance between poles increased. The cost of replacing malfunctioning BFDs is very high as there are serious health and safety constraints related to working with live wires. Factors aff ecting diverter malfunctioning need to be considered for future powerline projects and our information can serve as basis for developing national standards or regulations for powerline mitigation in Mongolia.

  19. Aspects of a potential impact of wind turbines on birds

    Directory of Open Access Journals (Sweden)

    Gabriel Fischer

    2005-11-01

    Full Text Available The electricity generated from renewable energy resources is an environmentally-preferred alternative to the conventionally produced electricity from fossil fuel and nuclear power plants. As the demand for a clean energy increases, the wind power generating stations are being constructed across Europe. However, concerns have been raised about the possible environmental impact of these turbines on birds. A research in this area has focused primarily on the mortality caused by birds striking turbine blades and associated wires. The disturbance to breeding, wintering or staging birds as a result of turbines has not been examined in detail. With respect to avian mortality at wind power generating stations, the greatest concern has been for raptors and migrating songbirds. The concern for raptors generally stems from the fact that many populations are small and thus even a few deaths can lead to declines. Songbirds are also considered at risk because they are known to fly into human-made structures (e.g. office towers, TV/microwave towers causing, on occasion, mass kills of thousands of individuals. While raptors and songbirds are generally at greatest risk of injury or death from turbines, the impact of such structures on all bird species should be considered on a site-by-site basis. Generally is possible to say that collisions with transmission and distribution lines, automobiles, trucks, tall building, residential house windows and lighted communication towers are more important for the avian mortality than the wind power generating stations.

  20. Apparent dissociation of photoperiodic time measurement between vernal migration and breeding under dim green light conditions in Gambel's white-crowned sparrow Zonotrichia leucophrys gambelii

    Directory of Open Access Journals (Sweden)

    Gang WANG, Marilyn RAMENOFSKY, John C. WINGFIELD

    2013-06-01

    Full Text Available In seasonally breeding birds, the annual cycle of photoperiod is a principal environmental cue for temporal arrangement of different life-history stages, such as migration and breeding. In the past, most research has focused on the mechanisms of photoperiodic control of breeding with less attention paid to migration. In Gambel’s white-crowned sparrow Zonotrichia leucophrys gambelii (GWCS, photoreceptors for induction of breeding are known to reside in the basal hypothalamus. However, it is unknown whether the sites of photoperiodic reception for vernal migration are the same as those for breeding. Therefore, we hypothesized that they may be controlled separately. In this study, we exposed photosensitive GWCSs to low-penetration green light (wavelength at 510 nm under a regime of 1 lux during the day and <0.1 lux at night, and switched the photoperiodic conditions from short day (10 h daytime to long day (18 h daytime. The results showed that the experimental birds developed traits associated with vernal migration including mass increase, fat deposition and migratory restlessness behavior when transferred from short day to long day green light cycles, while control birds maintained continuously on short day green light conditions did not express any migration related characteristics. Neither experimental nor control groups showed gonadal recrudescence under either green light cycles. In support of our hypothesis, we were able to apparently dissociate the photoperiodic responses regulating vernal migration and breeding, which suggests separate mechanisms of photoperiodic time measurement. Such distinct photoperiodic mechanisms may drive the fine-tuned temporal arrangement of the two life history stages [Current Zoology 59 (3: 349–359, 2013].

  1. Lessons learned from research and surveillance directed at highly pathogenic influenza A viruses in wild birds inhabiting North America.

    Science.gov (United States)

    Ramey, Andrew M; DeLiberto, Thomas J; Berhane, Yohannes; Swayne, David E; Stallknecht, David E

    2018-05-01

    Following detections of highly pathogenic (HP) influenza A viruses (IAVs) in wild birds inhabiting East Asia after the turn of the millennium, the intensity of sampling of wild birds for IAVs increased throughout much of North America. The objectives for many research and surveillance efforts were directed towards detecting Eurasian origin HP IAVs and understanding the potential of such viruses to be maintained and dispersed by wild birds. In this review, we highlight five important lessons learned from research and surveillance directed at HP IAVs in wild birds inhabiting North America: (1) Wild birds may disperse IAVs between North America and adjacent regions via migration, (2) HP IAVs can be introduced to wild birds in North America, (3) HP IAVs may cross the wild bird-poultry interface in North America, (4) The probability of encountering and detecting a specific virus may be low, and (5) Population immunity of wild birds may influence HP IAV outbreaks in North America. We review empirical support derived from research and surveillance efforts for each lesson learned and, furthermore, identify implications for future surveillance efforts, biosecurity, and population health. We conclude our review by identifying five additional areas in which we think future mechanistic research relative to IAVs in wild birds in North America are likely to lead to other important lessons learned in the years ahead. Published by Elsevier Inc.

  2. Lessons learned from research and surveillance directed at highly pathogenic influenza A viruses in wild birds inhabiting North America

    Science.gov (United States)

    Ramey, Andy M.; DeLiberto, Thomas J.; Berhane, Yohannes; Swayne, David E.; Stallknecht, David E.

    2018-01-01

    Following detections of highly pathogenic (HP) influenza A viruses (IAVs) in wild birds inhabiting East Asia after the turn of the millennium, the intensity of sampling of wild birds for IAVs increased throughout much of North America. The objectives for many research and surveillance efforts were directed towards detecting Eurasian origin HP IAVs and understanding the potential of such viruses to be maintained and dispersed by wild birds. In this review, we highlight five important lessons learned from research and surveillance directed at HP IAVs in wild birds inhabiting North America: (1) Wild birds may disperse IAVs between North America and adjacent regions via migration, (2) HP IAVs can be introduced to wild birds in North America, (3) HP IAVs may cross the wild bird-poultry interface in North America, (4) The probability of encountering and detecting a specific virus may be low, and (5) Population immunity of wild birds may influence HP IAV outbreaks in North America. We review empirical support derived from research and surveillance efforts for each lesson learned and, furthermore, identify implications for future surveillance efforts, biosecurity, and population health. We conclude our review by identifying five additional areas in which we think future mechanistic research relative to IAVs in wild birds in North America are likely to lead to other important lessons learned in the years ahead.

  3. The role of the North American Breeding Bird Survey in conservation

    Science.gov (United States)

    Hudson, Marie-Anne R.; Francis, Charles M.; Campbell, Kate J.; Downes, Constance M.; Smith, Adam C.; Pardieck, Keith L.

    2017-01-01

    The North American Breeding Bird Survey (BBS) was established in 1966 in response to a lack of quantitative data on changes in the populations of many bird species at a continental scale, especially songbirds. The BBS now provides the most reliable regional and continental trends and annual indices of abundance available for >500 bird species. This paper reviews some of the ways in which BBS data have contributed to bird conservation in North America over the past 50 yr, and highlights future program enhancement opportunities. BBS data have contributed to the listing of species under the Canadian Species at Risk Act and, in a few cases, have informed species assessments under the U.S. Endangered Species Act. By raising awareness of population changes, the BBS has helped to motivate bird conservation efforts through the creation of Partners in Flight. BBS data have been used to determine priority species and locations for conservation action at regional and national scales through Bird Conservation Region strategies and Joint Ventures. Data from the BBS have provided the quantitative foundation for North American State of the Birds reports, and have informed the public with regard to environmental health through multiple indicators, such as the Canadian Environmental Sustainability Indicators and the U.S. Environmental Protection Agency's Report on the Environment. BBS data have been analyzed with other data (e.g., environmental, land cover, and demographic) to evaluate potential drivers of population change, which have then informed conservation actions. In a few cases, BBS data have contributed to the evaluation of management actions, including informing the management of Mourning Doves (Zenaida macroura), Wood Ducks (Aix sponsa), and Golden Eagles (Aquila chrysaetos). Improving geographic coverage in northern Canada and in Mexico, improving the analytical approaches required to integrate data from other sources and to address variation in detectability, and

  4. Effect of geolocators on migration and subsequent breeding performance of a long-distance passerine migrant.

    Directory of Open Access Journals (Sweden)

    Debora Arlt

    Full Text Available Geolocators are small light-weight data loggers used to track individual migratory routes, and their use has increased exponentially in birds. However, the effects of geolocators on individual performance are still poorly known. We studied geolocator effects on a long-distance migrating passerine bird, the northern wheatear (Oenanthe oenanthe L.. We asked the general question of whether geolocators affect migratory behaviour and subsequent reproductive performance of small passerines by comparing arrival time, breeding time, breeding success and survival of geolocator versus control birds of known identity and breeding history. During two years geolocator birds (n=37 displayed a lower apparent survival (30% as compared to controls (45%, n=164. Furthermore, returning geolocator birds (n=12 arrived on average 3.5 days later, started laying eggs 6.3 days later, and had lower nest success (25% than control birds (78%. Our results suggest that geolocators affect migratory performance with carry-over effects to the timing of breeding and reproductive success in the subsequent breeding season. We discuss the implications of such geolocator effects for the study of migratory strategies of small passerines in general and suggest how to identify and investigate such effects in the future.

  5. Potential for an Arctic-breeding migratory bird to adjust spring migration phenology to Arctic amplification

    NARCIS (Netherlands)

    Lameris, T.K.; Scholten, Ilse; Bauer, S.; Cobben, M.M.P.; Ens, B.J.; Nolet, B.A.

    2017-01-01

    Arctic amplification, the accelerated climate warming in the polar regions, is causing a more rapid advancement of the onset of spring in the Arctic than in temperate regions. Consequently, the arrival of many migratory birds in the Arctic is thought to become increasingly mismatched with the onset

  6. Guam and the Northern Mariana Islands ESI: BIRDS (Bird Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for pelagic birds, shorebirds, wading birds, waterfowl, gulls, terns, and passerine birds in Guam and the...

  7. Resource tracking within and across continents in long-distance bird migrants

    KAUST Repository

    Thorup, Kasper

    2017-01-05

    Migratory birds track seasonal resources across and between continents. We propose a general strategy of tracking the broad seasonal abundance of resources throughout the annual cycle in the longest-distance migrating land birds as an alternative to tracking a certain climatic niche or shorter-term resource surplus occurring, for example, during spring foliation. Whether and how this is possible for complex annual spatiotemporal schedules is not known. New tracking technology enables unprecedented spatial and temporal mapping of long-distance movement of birds. We show that three Palearctic-African species track vegetation greenness throughout their annual cycle, adjusting the timing and direction of migratory movements with seasonal changes in resource availability over Europe and Africa. Common cuckoos maximize the vegetation greenness, whereas red-backed shrikes and thrush nightingales track seasonal surplus in greenness. Our results demonstrate that the longest-distance migrants move between consecutive staging areas even within the wintering region in Africa to match seasonal variation in regional climate. End-of-century climate projections indicate that optimizing greenness would be possible but that vegetation surplus might be more difficult to track in the future.

  8. Resource tracking within and across continents in long-distance bird migrants.

    Science.gov (United States)

    Thorup, Kasper; Tøttrup, Anders P; Willemoes, Mikkel; Klaassen, Raymond H G; Strandberg, Roine; Vega, Marta Lomas; Dasari, Hari P; Araújo, Miguel B; Wikelski, Martin; Rahbek, Carsten

    2017-01-01

    Migratory birds track seasonal resources across and between continents. We propose a general strategy of tracking the broad seasonal abundance of resources throughout the annual cycle in the longest-distance migrating land birds as an alternative to tracking a certain climatic niche or shorter-term resource surplus occurring, for example, during spring foliation. Whether and how this is possible for complex annual spatiotemporal schedules is not known. New tracking technology enables unprecedented spatial and temporal mapping of long-distance movement of birds. We show that three Palearctic-African species track vegetation greenness throughout their annual cycle, adjusting the timing and direction of migratory movements with seasonal changes in resource availability over Europe and Africa. Common cuckoos maximize the vegetation greenness, whereas red-backed shrikes and thrush nightingales track seasonal surplus in greenness. Our results demonstrate that the longest-distance migrants move between consecutive staging areas even within the wintering region in Africa to match seasonal variation in regional climate. End-of-century climate projections indicate that optimizing greenness would be possible but that vegetation surplus might be more difficult to track in the future.

  9. The geography of fear: a latitudinal gradient in anti-predator escape distances of birds across Europe.

    Directory of Open Access Journals (Sweden)

    Mario Díaz

    Full Text Available All animals flee from potential predators, and the distance at which this happens is optimized so the benefits from staying are balanced against the costs of flight. Because predator diversity and abundance decreases with increasing latitude, and differs between rural and urban areas, we should expect escape distance when a predator approached the individual to decrease with latitude and depend on urbanization. We measured the distance at which individual birds fled (flight initiation distance, FID, which represents a reliable and previously validated surrogate measure of response to predation risk following a standardized protocol in nine pairs of rural and urban sites along a ca. 3000 km gradient from Southern Spain to Northern Finland during the breeding seasons 2009-2010. Raptor abundance was estimated by means of standard point counts at the same sites where FID information was recorded. Data on body mass and phylogenetic relationships among bird species sampled were extracted from the literature. An analysis of 12,495 flight distances of 714 populations of 159 species showed that mean FID decreased with increasing latitude after accounting for body size and phylogenetic effects. This decrease was paralleled by a similar cline in an index of the abundance of raptors. Urban populations had consistently shorter FIDs, supporting previous findings. The difference between rural and urban habitats decreased with increasing latitude, also paralleling raptor abundance trends. Overall, the latitudinal gradient in bird fear was explained by raptor abundance gradients, with additional small effects of latitude and intermediate effects of habitat. This study provides the first empirical documentation of a latitudinal trend in anti-predator behavior, which correlated positively with a similar trend in the abundance of predators.

  10. Strategic Grassland Bird Conservation throughout the Annual Cycle: Linking Policy Alternatives, Landowner Decisions, and Biological Population Outcomes.

    Directory of Open Access Journals (Sweden)

    Ryan G Drum

    Full Text Available Grassland bird habitat has declined substantially in the United States. Remaining grasslands are increasingly fragmented, mostly privately owned, and vary greatly in terms of habitat quality and protection status. A coordinated strategic response for grassland bird conservation is difficult, largely due to the scope and complexity of the problem, further compounded by biological, sociological, and economic uncertainties. We describe the results from a collaborative Structured Decision Making (SDM workshop focused on linking social and economic drivers of landscape change to grassland bird population outcomes. We identified and evaluated alternative strategies for grassland bird conservation using a series of rapid prototype models. We modeled change in grassland and agriculture cover in hypothetical landscapes resulting from different landowner decisions in response to alternative socio-economic conservation policy decisions. Resulting changes in land cover at all three stages of the annual cycle (breeding, wintering, and migration were used to estimate changes in grassland bird populations. Our results suggest that successful grassland bird conservation may depend upon linkages with ecosystem services on working agricultural lands and grassland-based marketing campaigns to engage the public. With further development, spatial models that link landowner decisions with biological outcomes can be essential tools for making conservation policy decisions. A coordinated non-traditional partnership will likely be necessary to clearly understand and systematically respond to the many conservation challenges facing grassland birds.

  11. Strategic Grassland Bird Conservation throughout the annual cycle: Linking policy alternatives, landowner decisions, and biological population outcomes

    Science.gov (United States)

    Drum, Ryan G.; Ribic, Christine; Koch, Katie; Lonsdorf, Eric V.; Grant, Edward C.; Ahlering, Marissa; Barnhill, Laurel; Dailey, Thomas; Lor, Socheata; Mueller, Connie; Pavlacky, D.C.; Rideout, Catherine; Sample, David W.

    2015-01-01

    Grassland bird habitat has declined substantially in the United States. Remaining grasslands are increasingly fragmented, mostly privately owned, and vary greatly in terms of habitat quality and protection status. A coordinated strategic response for grassland bird conservation is difficult, largely due to the scope and complexity of the problem, further compounded by biological, sociological, and economic uncertainties. We describe the results from a collaborative Structured Decision Making (SDM) workshop focused on linking social and economic drivers of landscape change to grassland bird population outcomes. We identified and evaluated alternative strategies for grassland bird conservation using a series of rapid prototype models. We modeled change in grassland and agriculture cover in hypothetical landscapes resulting from different landowner decisions in response to alternative socio-economic conservation policy decisions. Resulting changes in land cover at all three stages of the annual cycle (breeding, wintering, and migration) were used to estimate changes in grassland bird populations. Our results suggest that successful grassland bird conservation may depend upon linkages with ecosystem services on working agricultural lands and grassland-based marketing campaigns to engage the public. With further development, spatial models that link landowner decisions with biological outcomes can be essential tools for making conservation policy decisions. A coordinated non-traditional partnership will likely be necessary to clearly understand and systematically respond to the many conservation challenges facing grassland birds.

  12. Rhode Island, Connecticut, New York, and New Jersey ESI: BIRDS (Bird Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for wading birds, shorebirds, waterfowl, raptors, diving birds, pelagic birds, passerine birds, gulls and...

  13. Drug metabolism in birds

    Science.gov (United States)

    Pan, Huo Ping; Fouts, James R.

    1979-01-01

    Papers published over 100 years since the beginning of the scientific study of drug metabolism in birds were reviewed. Birds were found to be able to accomplish more than 20 general biotransformation reactions in both functionalization and conjugation. Chickens were the primary subject of study but over 30 species of birds were used. Large species differences in drug metabolism exist between birds and mammals as well as between various birds, these differences were mostly quantitative. Qualitative differences were rare. On the whole, drug metabolism studies in birds have been neglected as compared with similar studies on insects and mammals. The uniqueness of birds and the advantages of using birds in drug metabolism studies are discussed. Possible future studies of drug metabolism in birds are recommended.

  14. On-Board Video Recording Unravels Bird Behavior and Mortality Produced by High-Speed Trains

    Directory of Open Access Journals (Sweden)

    Eladio L. García de la Morena

    2017-10-01

    Full Text Available Large high-speed railway (HSR networks are planned for the near future to accomplish increased transport demand with low energy consumption. However, high-speed trains produce unknown avian mortality due to birds using the railway and being unable to avoid approaching trains. Safety and logistic difficulties have precluded until now mortality estimation in railways through carcass removal, but information technologies can overcome such problems. We present the results obtained with an experimental on-board system to record bird-train collisions composed by a frontal recording camera, a GPS navigation system and a data storage unit. An observer standing in the cabin behind the driver controlled the system and filled out a form with data of collisions and bird observations in front of the train. Photographs of the train front taken before and after each journey were used to improve the record of killed birds. Trains running the 321.7 km line between Madrid and Albacete (Spain at speeds up to 250–300 km/h were equipped with the system during 66 journeys along a year, totaling approximately 14,700 km of effective recording. The review of videos produced 1,090 bird observations, 29.4% of them corresponding to birds crossing the infrastructure under the catenary and thus facing collision risk. Recordings also showed that 37.7% bird crossings were of animals resting on some element of the infrastructure moments before the train arrival, and that the flight initiation distance of birds (mean ± SD was between 60 ± 33 m (passerines and 136 ± 49 m (raptors. Mortality in the railway was estimated to be 60.5 birds/km year on a line section with 53 runs per day and 26.1 birds/km year in a section with 25 runs per day. Our results are the first published estimation of bird mortality in a HSR and show the potential of information technologies to yield useful data for monitoring the impact of trains on birds via on-board recording systems. Moreover

  15. Prevalence and Diversity of Low Pathogenicity Avian Influenza Viruses in Wild Birds in Guatemala, 2010-2013.

    Science.gov (United States)

    Gonzalez-Reiche, Ana S; Müller, Maria L; Ortiz, Lucía; Cordón-Rosales, Celia; Perez, Daniel R

    2016-05-01

    Waterfowl species are known to harbor the greatest diversity of low pathogenicity influenza A virus (LPAIV) subtypes and are recognized as their main natural reservoir. In Guatemala there is evidence of circulation of LPAIV in wild ducks; however, the bird species contributing to viral diversity during the winter migration in Central America are unknown. In this study, samples obtained from 1250 hunter-killed birds from 22 different species were collected on the Pacific coast of Guatemala during three winter migration seasons between 2010 and 2013. Prevalence of LPAIV detected by real-time reverse-transcriptase polymerase chain reaction was 38.2%, 23.5%, and 24.7% in the 2010-11, 2011-12, and 2012-13 seasons, respectively. The highest virus prevalence was detected in the northern shoveler (Anas clypeata), followed by the blue-winged teal (Anas discors). The majority of positive samples and viral isolates were obtained from the blue-winged teal. Analysis of LPAIV prevalence over time in this species indicated a decreasing trend in monthly prevalence within a migration season. Sixty-eight viruses were isolated, and nine HA and seven NA subtypes were identified in 19 subtype combinations. In 2012-13 the most prevalent subtype was H14, a subtype identified for the first time in the Western Hemisphere in 2010. The results from this study represent the most detailed description available to date of LPAIV circulation in Central America.

  16. Do night-active birds lack daily melatonin rhythms? A case study comparing a diurnal and a nocturnal-foraging gull species

    NARCIS (Netherlands)

    Wikelski, M; Tarlow, EM; Eising, CM; Groothuis, TGG; Gwinner, E; Tarlow, Elisa M.; Groothuis, Ton G.G.; Bairlein, F.

    Plasma melatonin concentrations in most animals investigated so far increase at night regardless of whether individuals are day or night active. Nevertheless, daily melatonin amplitudes are often seasonally adjusted to ecological conditions, with birds that breed at high latitudes and migrate during

  17. Why birds with deferred sexual maturity are sedentary on islands: a systematic review.

    Directory of Open Access Journals (Sweden)

    Miguel Ferrer

    Full Text Available BACKGROUND: Island faunas have played central roles in the development of evolutionary biology and ecology. Birds are among the most studied organisms on islands, in part because of their dispersal powers linked to migration. Even so, we lack of information about differences in the movement ecology of island versus mainland populations of birds. METHODOLOGY/PRINCIPAL FINDINGS: Here we present a new general pattern indicating that large birds with deferred sexual maturity are sedentary on islands, and that they become so even when they are migratory on the mainland. Density-dependent variation in the age at first breeding affects the survivorship of insular populations and this, in turn, affects the movement ecology of large birds. Because density-dependent variation in the age of first breeding is critical to the long-term survival of small isolated populations of long-lived species, migratory forms can successfully colonize islands only if they become sedentary once there. Analyses of the movement ecology of continental and insular populations of 314 species of raptors, 113 species of Ciconiiformes and 136 species of passerines, along with individual-based population simulations confirm this prediction. CONCLUSIONS: This finding has several consequences for speciation, colonization and survival of small isolated population of species with deferred sexual maturity.

  18. Migrating birds’ use of stopover habitat in the southwestern United States

    Science.gov (United States)

    Ruth, Janet M.; Diehl, R.H.; Felix, R.K.

    2012-01-01

    In the arid Southwest, migratory birds are known to use riparian stopover habitats; we know less about how migrants use other habitat types during migratory stopover. Using radar data and satellite land-cover data, we determined the habitats with which birds are associated during migration stopover. Bird densities differed significantly by habitat type at all sites in at least one season. In parts of Arizona and New Mexico upland forest supported high densities of migrants, especially in fall. Developed habitat, in areas with little upland forest, also supported high densities of migrants. Scrub/shrub and grassland habitats supported low to intermediate densities, but because these habitat types dominate the Southwestern landscape, they may provide stopover habitat for larger numbers of migratory birds than previously recognized. These results are complicated by continuing challenges related to target identity (i.e., distinguishing among birds, arthropods and bats). Our results suggest that it is too simplistic to (1) consider the arid West as a largely inhospitable landscape in which there are only relatively small oases of habitat that provide the resources needed by all migrants, (2) think of western riparian and upland forests as supporting the majority of migrants in all cases, and (3) consider a particular habitat unimportant for stopover solely on the basis of low densities of migrants.

  19. Correlated evolution of sternal keel length and ilium length in birds

    Directory of Open Access Journals (Sweden)

    Tao Zhao

    2017-07-01

    Full Text Available The interplay between the pectoral module (the pectoral girdle and limbs and the pelvic module (the pelvic girdle and limbs plays a key role in shaping avian evolution, but prior empirical studies on trait covariation between the two modules are limited. Here we empirically test whether (size-corrected sternal keel length and ilium length are correlated during avian evolution using phylogenetic comparative methods. Our analyses on extant birds and Mesozoic birds both recover a significantly positive correlation. The results provide new evidence regarding the integration between the pelvic and pectoral modules. The correlated evolution of sternal keel length and ilium length may serve as a mechanism to cope with the effect on performance caused by a tradeoff in muscle mass between the pectoral and pelvic modules, via changing moment arms of muscles that function in flight and in terrestrial locomotion.

  20. Birds and Aircraft on Midway Islands, 1959-63 Investigations

    Science.gov (United States)

    Robbins, C.S.

    1966-01-01

    At Midway Naval Station, 1.100 miles west-northwest of Honolulu, military aircraft collide with flying albatrosses at the rate of about 300 to 400 per year. One aircraft out of every five that hits an albatross on takeoff either aborts (stops before it is airborne), or dumps fuel and returns for appraisal of damage. About 70,000 pairs of Laysan albatrosses and 7,000 pairs of blackfooted albatrosses nest at Midway in any given year. The population is declining. Two-thirds or more of the birds of breeding age nest each year. The minimum breeding age recorded is 5 years (each species), but many individuals do not nest until at least 7 years of age. Young birds begin to return to Midway at 3 years of age and are found more frequently as breeding age approaches. They come ashore more frequently in March and April (the high bird strike months) than in midwinter. Even in midwinter the number of 'walkers' (birds not on nests) may comprise more than 40 percent of the albatrosses present on Sand Island, Midway. Maximum longevity of the Laysan albatross is believed to exceed 40 years; 6 out of 99 birds banded as breeding adults (7+ years old) were still alive 24 years after banding. Control methods tested experimentally include disturbance, gunfire, other sounds, radar beams, smoke, odors, destruction of nests, eggs, chicks, and adults, moving of birds, eggs, and chicks, erection of obstacles to flight, and habitat management. Habitat management (leveling and hardsurfacing of shoulders of runways) has been the most effective. Albatrosses were counted over the runways at 10 locations in 1957, 1958, and 1960 to determine the effects of wind direction, wind speed, and topography on the numbers of flying birds. Birds were most concentrated in areas where rising air currents were created as winds blew against dunes or tall trees. Soaring and strike rate both increased with greater wind speeds. There was a highly significant correlation between strike frequency and wind direction