WorldWideScience

Sample records for bird migration flight

  1. Long migration flights of birds

    International Nuclear Information System (INIS)

    Denny, Mark

    2014-01-01

    The extremely long migration flights of some birds are carried out in one hop, necessitating a substantial prior build-up of fat fuel. We summarize the basic elements of bird flight physics with a simple model, and show how the fat reserves influence flight distance, flight speed and the power expended by the bird during flight. (paper)

  2. Long migration flights of birds

    Science.gov (United States)

    Denny, Mark

    2014-05-01

    The extremely long migration flights of some birds are carried out in one hop, necessitating a substantial prior build-up of fat fuel. We summarize the basic elements of bird flight physics with a simple model, and show how the fat reserves influence flight distance, flight speed and the power expended by the bird during flight.

  3. Flight mode affects allometry of migration range in birds.

    Science.gov (United States)

    Watanabe, Yuuki Y

    2016-08-01

    Billions of birds migrate to exploit seasonally available resources. The ranges of migration vary greatly among species, but the underlying mechanisms are poorly understood. I hypothesise that flight mode (flapping or soaring) and body mass affect migration range through their influence on flight energetics. Here, I compiled the tracks of migratory birds (196 species, weighing 12-10 350 g) recorded by electronic tags in the last few decades. In flapping birds, migration ranges decreased with body mass, as predicted from rapidly increasing flight cost with increasing body mass. The species with higher aspect ratio and lower wing loading had larger migration ranges. In soaring birds, migration ranges were mass-independent and larger than those of flapping birds, reflecting their low flight costs irrespective of body mass. This study demonstrates that many animal-tracking studies are now available to explore the general patterns and the underlying mechanisms of animal migration. © 2016 John Wiley & Sons Ltd/CNRS.

  4. Flight by night or day? Optimal daily timing of bird migration.

    Science.gov (United States)

    Alerstam, Thomas

    2009-06-21

    Many migratory bird species fly mainly during the night (nocturnal migrants), others during daytime (diurnal migrants) and still others during both night and day. Need to forage during the day, atmospheric structure, predator avoidance and orientation conditions have been proposed as explanations for the widespread occurrence of nocturnal migration. However, the general principles that determine the basic nocturnal-diurnal variation in flight habits are poorly known. In the present study optimal timing of migratory flights, giving the minimum total duration of the migratory journey, is evaluated in a schematic way in relation to ecological conditions for energy gain in foraging and for energy costs in flight. There exists a strong and fundamental advantage of flying by night because foraging time is maximized and energy deposition can take place on days immediately after and prior to the nocturnal flights. The increase in migration speed by nocturnal compared with diurnal migration will be largest for birds with low flight costs and high energy deposition rates. Diurnal migration will be optimal if it is associated with efficient energy gain immediately after a migratory flight because suitable stopover/foraging places have been located during the flight or if energy losses during flight are substantially reduced by thermal soaring and/or by fly-and-forage migration. A strategy of combined diurnal and nocturnal migration may be optimal when birds migrate across regions with relatively poor conditions for energy deposition (not only severe but also soft barriers). Predictions about variable timing of migratory flights depending on changing foraging and environmental conditions along the migration route may be tested for individual birds by analysing satellite tracking results with respect to daily travel routines in different regions. Documenting and understanding the adaptive variability in daily travel schedules among migrating animals constitute a fascinating

  5. Oxidative stress in endurance flight: an unconsidered factor in bird migration.

    Directory of Open Access Journals (Sweden)

    Susanne Jenni-Eiermann

    Full Text Available Migrating birds perform extraordinary endurance flights, up to 200 h non-stop, at a very high metabolic rate and while fasting. Such an intense and prolonged physical activity is normally associated with an increased production of reactive oxygen and nitrogen species (RONS and thus increased risk of oxidative stress. However, up to now it was unknown whether endurance flight evokes oxidative stress. We measured a marker of oxidative damage (protein carbonyls, PCs and a marker of enzymatic antioxidant capacity (glutathione peroxidase, GPx in the European robin (Erithacus rubecula, a nocturnal migrant, on its way to the non-breeding grounds. Both markers were significantly higher in European robins caught out of their nocturnal flight than in conspecifics caught during the day while resting. Independently of time of day, both markers showed higher concentrations in individuals with reduced flight muscles. Adults had higher GPx concentrations than first-year birds on their first migration. These results show for the first time that free-flying migrants experience oxidative stress during endurance flight and up-regulate one component of antioxidant capacity. We discuss that avoiding oxidative stress may be an overlooked factor shaping bird migration strategies, e.g. by disfavouring long non-stop flights and an extensive catabolism of the flight muscles.

  6. Route simulations, compass mechanisms and long-distance migration flights in birds.

    Science.gov (United States)

    Åkesson, Susanne; Bianco, Giuseppe

    2017-07-01

    Bird migration has fascinated humans for centuries and routes crossing the globe are now starting to be revealed by advanced tracking technology. A central question is what compass mechanism, celestial or geomagnetic, is activated during these long flights. Different approaches based on the geometry of flight routes across the globe and route simulations based on predictions from compass mechanisms with or without including the effect of winds have been used to try to answer this question with varying results. A major focus has been use of orthodromic (great circle) and loxodromic (rhumbline) routes using celestial information, while geomagnetic information has been proposed for both a magnetic loxodromic route and a magnetoclinic route. Here, we review previous results and evaluate if one or several alternative compass mechanisms can explain migration routes in birds. We found that most cases could be explained by magnetoclinic routes (up to 73% of the cases), while the sun compas s could explain only 50%. Both magnetic and geographic loxodromes could explain <25% of the routes. The magnetoclinic route functioned across latitudes (1°S-74°N), while the sun compass only worked in the high Arctic (61-69°N). We discuss the results with respect to orientation challenges and availability of orientation cues.

  7. Bird migration flight altitudes studied by a network of operational weather radars.

    Science.gov (United States)

    Dokter, Adriaan M; Liechti, Felix; Stark, Herbert; Delobbe, Laurent; Tabary, Pierre; Holleman, Iwan

    2011-01-06

    A fully automated method for the detection and quantification of bird migration was developed for operational C-band weather radar, measuring bird density, speed and direction as a function of altitude. These weather radar bird observations have been validated with data from a high-accuracy dedicated bird radar, which was stationed in the measurement volume of weather radar sites in The Netherlands, Belgium and France for a full migration season during autumn 2007 and spring 2008. We show that weather radar can extract near real-time bird density altitude profiles that closely correspond to the density profiles measured by dedicated bird radar. Doppler weather radar can thus be used as a reliable sensor for quantifying bird densities aloft in an operational setting, which--when extended to multiple radars--enables the mapping and continuous monitoring of bird migration flyways. By applying the automated method to a network of weather radars, we observed how mesoscale variability in weather conditions structured the timing and altitude profile of bird migration within single nights. Bird density altitude profiles were observed that consisted of multiple layers, which could be explained from the distinct wind conditions at different take-off sites. Consistently lower bird densities are recorded in The Netherlands compared with sites in France and eastern Belgium, which reveals some of the spatial extent of the dominant Scandinavian flyway over continental Europe.

  8. 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.

  9. Use of multiple modes of flight subsidy by a soaring terrestrial bird, the golden eagle Aquila chrysaetos, when on migration.

    Science.gov (United States)

    Katzner, Todd E; Turk, Philip J; Duerr, Adam E; Miller, Tricia A; Lanzone, Michael J; Cooper, Jeff L; Brandes, David; Tremblay, Junior A; Lemaître, Jérôme

    2015-11-06

    Large birds regularly use updrafts to subsidize flight. Although most research on soaring bird flight has focused on use of thermal updrafts, there is evidence suggesting that many species are likely to use multiple modes of subsidy. We tested the degree to which a large soaring species uses multiple modes of subsidy to provide insights into the decision-making that underlies flight behaviour. We statistically classified more than 22 000 global positioning satellite-global system for mobile communications telemetry points collected at 30-s intervals to identify the type of subsidized flight used by 32 migrating golden eagles during spring in eastern North America. Eagles used subsidized flight on 87% of their journey. They spent 41.9% ± 1.5 ([Formula: see text], range: 18-56%) of their subsidized northbound migration using thermal soaring, 45.2% ± 2.1 (12-65%) of time gliding between thermals, and 12.9% ± 2.2 (1-55%) of time using orographic updrafts. Golden eagles responded to the variable local-scale meteorological events they encountered by switching flight behaviour to take advantage of multiple modes of subsidy. Orographic soaring occurred more frequently in morning and evening, earlier in the migration season, and when crosswinds and tail winds were greatest. Switching between flight modes allowed migration for relatively longer periods each day and frequent switching behaviour has implications for a better understanding of avian flight behaviour and of the evolution of use of subsidy in flight. © 2015 The Author(s).

  10. A polar system of intercontinental bird migration

    OpenAIRE

    Alerstam, Thomas; Bäckman, Johan; Gudmundsson, Gudmundur A; Hedenström, Anders; Henningsson, Sara S; Karlsson, Håkan; Rosén, Mikael; Strandberg, Roine

    2007-01-01

    Studies of bird migration in the Beringia region of Alaska and eastern Siberia are of special interest for revealing the importance of bird migration between Eurasia and North America, for evaluating orientation principles used by the birds at polar latitudes and for understanding the evolutionary implications of intercontinental migratory connectivity among birds as well as their parasites. We used tracking radar placed onboard the ice-breaker Oden to register bird migratory flights from 30 ...

  11. Biomechanics of bird flight.

    Science.gov (United States)

    Tobalske, Bret W

    2007-09-01

    Power output is a unifying theme for bird flight and considerable progress has been accomplished recently in measuring muscular, metabolic and aerodynamic power in birds. The primary flight muscles of birds, the pectoralis and supracoracoideus, are designed for work and power output, with large stress (force per unit cross-sectional area) and strain (relative length change) per contraction. U-shaped curves describe how mechanical power output varies with flight speed, but the specific shapes and characteristic speeds of these curves differ according to morphology and flight style. New measures of induced, profile and parasite power should help to update existing mathematical models of flight. In turn, these improved models may serve to test behavioral and ecological processes. Unlike terrestrial locomotion that is generally characterized by discrete gaits, changes in wing kinematics and aerodynamics across flight speeds are gradual. Take-off flight performance scales with body size, but fully revealing the mechanisms responsible for this pattern awaits new study. Intermittent flight appears to reduce the power cost for flight, as some species flap-glide at slow speeds and flap-bound at fast speeds. It is vital to test the metabolic costs of intermittent flight to understand why some birds use intermittent bounds during slow flight. Maneuvering and stability are critical for flying birds, and design for maneuvering may impinge upon other aspects of flight performance. The tail contributes to lift and drag; it is also integral to maneuvering and stability. Recent studies have revealed that maneuvers are typically initiated during downstroke and involve bilateral asymmetry of force production in the pectoralis. Future study of maneuvering and stability should measure inertial and aerodynamic forces. It is critical for continued progress into the biomechanics of bird flight that experimental designs are developed in an ecological and evolutionary context.

  12. Insights on the thermal impacts of wing colorization of migrating birds on their skin friction drag and the choice of their flight route.

    Science.gov (United States)

    Hassanalian, M; Ayed, S Ben; Ali, M; Houde, P; Hocut, C; Abdelkefi, A

    2018-02-01

    The thermal effects of wing color in flight is investigated in four species of birds with respect to their flight routes, migration time, and geometric and behavioral characteristics. Considering the marine and atmospheric characteristics of these flight routes, a thermal analysis of the birds' wings is performed during their migration. The surrounding fluxes including the ocean flux and the solar irradiance are considered in an energy balance in order to determine the skin temperature of both sides of the wing. Applying the Blasius solution for heated boundary layers, it is shown that the color configuration of these migrating birds, namely black on the top side of the wings and white on the bottom side of the wings ("countershading"), results in a skin drag reduction, if compared to some other configurations, when both day and night are taken into consideration. This drag reduction can be considered as one of the effective factors for long endurance of these migrating birds. This research can provide the evolutionary perspective behind the colorization of these migrating birds. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. 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.

  14. Is long-distance bird flight equivalent to a high-energy fast? Body composition changes in freely migrating and captive fasting great knots

    NARCIS (Netherlands)

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

    2001-01-01

    We studied changes in body composition in great knots, Calidris tenuirostris, before and after a migratory flight of 5,400 km from northwest Australia to eastern China. We also took premigratory birds into captivity and fasted them down to their equivalent arrival mass after migration to compare

  15. Relation between travel strategy and social organization of migrating birds with special consideration of formation flight in the northern bald ibis.

    Science.gov (United States)

    Voelkl, B; Fritz, J

    2017-08-19

    A considerable proportion of the world's bird species undertake seasonal long-distance migrations. These journeys are energetically demanding. Two major behavioural means to reduce energy expenditure have been suggested: the use of thermal uplifts for a soaring-gliding migration style and travelling in echelon or V-shaped formation. Both strategies have immediate consequences for the social organization of the birds as they either cause large aggregations or require travelling in small and stable groups. Here, we first discuss those consequences, and second present an analysis of formation flight in a flock of northern bald ibis on their first southbound migration. We observe clear correlations between leading and trailing on the dyadic level but only a weak correlation on the individual level during independent flight and no convincing correlation during the human guided part of the migration. This pattern is suggestive of direct reciprocation as a means for establishing cooperation during formation flight. In general, we conclude that behavioural adaptations for dealing with physiological constraints on long-distance migrations either necessitate or ultimately foster formation of social groups with different characteristics. Patterns and social organization of birds travelling in groups have been elusive to study; however, new tracking technology-foremost lightweight GPS units-will provide more insights in the near future.This article is part of the themed issue 'Physiological determinants of social behaviour in animals'. © 2017 The Author(s).

  16. A polar system of intercontinental bird migration.

    Science.gov (United States)

    Alerstam, Thomas; Bäckman, Johan; Gudmundsson, Gudmundur A; Hedenström, Anders; Henningsson, Sara S; Karlsson, Håkan; Rosén, Mikael; Strandberg, Roine

    2007-10-22

    Studies of bird migration in the Beringia region of Alaska and eastern Siberia are of special interest for revealing the importance of bird migration between Eurasia and North America, for evaluating orientation principles used by the birds at polar latitudes and for understanding the evolutionary implications of intercontinental migratory connectivity among birds as well as their parasites. We used tracking radar placed onboard the ice-breaker Oden to register bird migratory flights from 30 July to 19 August 2005 and we encountered extensive bird migration in the whole Beringia range from latitude 64 degrees N in Bering Strait up to latitude 75 degrees N far north of Wrangel Island, with eastward flights making up 79% of all track directions. The results from Beringia were used in combination with radar studies from the Arctic Ocean north of Siberia and in the Beaufort Sea to make a reconstruction of a major Siberian-American bird migration system in a wide Arctic sector between longitudes 110 degrees E and 130 degrees W, spanning one-third of the entire circumpolar circle. This system was estimated to involve more than 2 million birds, mainly shorebirds, terns and skuas, flying across the Arctic Ocean at mean altitudes exceeding 1 km (maximum altitudes 3-5 km). Great circle orientation provided a significantly better fit with observed flight directions at 20 different sites and areas than constant geographical compass orientation. The long flights over the sea spanned 40-80 degrees of longitude, corresponding to distances and durations of 1400-2600 km and 26-48 hours, respectively. The birds continued from this eastward migration system over the Arctic Ocean into several different flyway systems at the American continents and the Pacific Ocean. Minimization of distances between tundra breeding sectors and northerly stopover sites, in combination with the Beringia glacial refugium and colonization history, seemed to be important for the evolution of this major

  17. Nocturnal bird migration in opaque clouds

    Science.gov (United States)

    Griffin, D. R.

    1972-01-01

    The use of a tracking radar to measure the flight paths of migrating birds on nights with opaque clouds is discussed. The effects of wind and lack of visual references are examined. The limitations of the radar observations are described, and samples of tracks obtained during radar observations are included. It is concluded that nonvisual mechanisms of orientation make it possible for birds to migrate in opaque clouds, but the exact nature of the sensory information cannot be determined by radar observations.

  18. Is long-distance bird flight equivalent to a high-energy fast? Body composition changes in freely migrating and captive fasting great knots.

    Science.gov (United States)

    Battley, P F; Dietz, M W; Piersma, T; Dekinga, A; Tang, S; Hulsman, K

    2001-01-01

    We studied changes in body composition in great knots, Calidris tenuirostris, before and after a migratory flight of 5,400 km from northwest Australia to eastern China. We also took premigratory birds into captivity and fasted them down to their equivalent arrival mass after migration to compare organ changes and nutrient use in a low-energy-turnover fast with a high-energy-turnover fast (migratory flight). Migrated birds were as economical as any fasting animal measured yet at conserving protein: their estimated relative protein contribution (RPC) to the energy used was 4.0%. Fasted birds had an estimated RPC of 6.8% and, consequently, a much lower lean mass and higher fat content for an equivalent body mass than migrated birds. Lean tissue was catabolized from most organs in both groups, except the brain. Furthermore, a principal components biplot showed that individuals were grouped primarily on the basis of overall organ fat or lean tissue content rather than by the size of specific organs. This indicates that organ changes during migratory flight are similar to those of a low-energy fast, although the length of the fast in this study probably accentuated organ reductions in some functional groups. Whether the metabolic characteristics of a flying migratory fast follow the three-phase model described in many inactive fasting animals is unclear. We have some evidence for skeletal fat being catabolized without phase 3 of a fast having been reached.

  19. Tracking migrating birds

    DEFF Research Database (Denmark)

    Willemoes, Mikkel

    Migratory movements of birds has always fascinated man and led to many questions concerning the ecological drivers behind, the necessary adaptations and the navigational abilities required. However, especially for the long-distance migrants, basic descriptions of their movements are still lacking...... 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......, and conclude that the currently believed theoretical framework is insufficient to explain the observed performance. The other study investigates the ability of a displaced experienced migrant to navigate back to the normal migration route. It documents the capability, but also finds interesting patterns...

  20. Flight costs and fuel composition of a bird migrating in a wind-tunnel

    NARCIS (Netherlands)

    Klaassen, M.R.J.; Kvist, A.; Lindström, A.

    2000-01-01

    We studied the energy and protein balance of a Thrush Nightingale Luscinia luscinia, a small long-distance migrant, during repeated 12-hr long Eights in a wind tunnel and during subsequent two-day fueling periods. From the energy budgets we estimated the power requirements for migratory flight in

  1. Migration in birds and fishes

    NARCIS (Netherlands)

    Verwey, J.

    1949-01-01

    Our knowledge concerning the periodical movements in animals called migrations is chiefly based on observations on birds. By and by, however, a number of facts concerning migration in other animal groups have been assembled and it seems worth while to compare them with those known for birds. There

  2. Radar studies of bird migration

    Science.gov (United States)

    Williams, T. C.; Williams, J. M.

    1974-01-01

    Observations of bird migration with NASA radars were made at Wallops Island, Va. Simultaneous observations were made at a number of radar sites in the North Atlantic Ocean in an effort to discover what happened to those birds that were observed leaving the coast of North America headed toward Bermuda, the Caribbean and South America. Transatlantic migration, utilizing observations from a large number of radars is discussed. Detailed studies of bird movements at Wallops Island are presented.

  3. The physiological basis of bird flight.

    Science.gov (United States)

    Butler, Patrick J

    2016-09-26

    Flapping flight is energetically more costly than running, although it is less costly to fly a given body mass a given distance per unit time than it is for a similar mass to run the same distance per unit time. This is mainly because birds can fly faster than they can run. Oxygen transfer and transport are enhanced in migrating birds compared with those in non-migrators: at the gas-exchange regions of the lungs the effective area is greater and the diffusion distance smaller. Also, migrating birds have larger hearts and haemoglobin concentrations in the blood, and capillary density in the flight muscles tends to be higher. Species like bar-headed geese migrate at high altitudes, where the availability of oxygen is reduced and the energy cost of flapping flight increased compared with those at sea level. Physiological adaptations to these conditions include haemoglobin with a higher affinity for oxygen than that in lowland birds, a greater effective ventilation of the gas-exchange surface of the lungs and a greater capillary-to-muscle fibre ratio. Migrating birds use fatty acids as their source of energy, so they have to be transported at a sufficient rate to meet the high demand. Since fatty acids are insoluble in water, birds maintain high concentrations of fatty acid-binding proteins to transport fatty acids across the cell membrane and within the cytoplasm. The concentrations of these proteins, together with that of a key enzyme in the β-oxidation of fatty acids, increase before migration.This article is part of the themed issue 'Moving in a moving medium: new perspectives on flight'. © 2016 The Author(s).

  4. Metabolic constraints on long-distance migration in birds

    NARCIS (Netherlands)

    Klaassen, M.R.J.

    1996-01-01

    The flight range of migrating birds depends crucially on the amount of fuel stored by the bird prior to migration or taken up en route at stop-over sites. However, an increase in body mass is associated with an increase in energetic costs, counteracting the benefit of fuel stores. Water imbalance,

  5. 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

  6. 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 migrants than autumn migration. Information about the behavior and interactions of migrants during the nonbreeding season in sub-Saharan Africa is also scarce for many species. Furthermore, very little is known about intra-African migration. This thesis summarizes my research on the autumn migration...... 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...

  7. 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...

  8. Tracking migrating birds

    DEFF Research Database (Denmark)

    Willemoes, Mikkel

    and many experiments are only becoming possible with the current development of tracking technologies. During this thesis work I have been tracking the poorly known movements of several species of long-distance migrants and document highly complex migration patterns. In three manuscripts these movements......, and conclude that the currently believed theoretical framework is insufficient to explain the observed performance. The other study investigates the ability of a displaced experienced migrant to navigate back to the normal migration route. It documents the capability, but also finds interesting patterns...... were related to the yearly progression of an environmental surrogate for food availability along the course of migration. In one species, with multiple, different non-breeding staging sites, environmental conditions explain movements well and also how yearly differences explain differences in timing...

  9. Bird Migration Echoes Observed by Polarimetric Radar

    OpenAIRE

    MINDA, Haruya; FURUZAWA, Fumie A.; SATOH, Shinsuke; NAKAMURA, Kenji

    2008-01-01

    A C-band polarimetric radar on Okinawa Island successfully observed large-scale bird migrations over the western Pacific Ocean. The birds generated interesting polarimetric signatures. This paper describes the signatures and speculates bird behavior.

  10. Bird Flight and Satish Dhawan

    Indian Academy of Sciences (India)

    One day out of the great wilderness of the water there came an albatross. Circling the ship on .... and mathematicians. Conventional aerodynamic ... suspended in air has inspired over a dozen aerodynamic models. GENERAL I ARTICLE scaling concepts fail to explain subtle features of bird flight, as debated by over fifty ...

  11. Bird Flight and Satish Dhawan

    Indian Academy of Sciences (India)

    business opportunities for universities, laboratories and corpo- rations. Modern scientists seem to be getting increasingly ob- sessed with seasonal and sensational .... around SHAR and the Nelapattu Sanctuary, Professor Dhawan distilled the essence of bird flight for the expert and the neo- phyte alike. The sheer biometric ...

  12. The Aerodynamics of Bird Flight

    Science.gov (United States)

    Spedding, Geoffrey

    2002-11-01

    The manifest success of birds in flight over small and large distances, in confined quarters and also in gusty conditions has inspired admiration, investigation and sometimes imitation from the earthbound human. Birds occupy a range of scales (2 g - 12 kg in mass, and 0.05 - 3 m in wingspan) that overlaps certain micro air vehicle (MAV) designs and there is interest in whether some bird-like properties (flapping wings, deformable feathers, movable tails) might be useful or even necessary for successful MAVs. A bird with 5 cm mean chord flying at 8 m/s has a nominal Reynolds number of 2 - 3 x 10^4. This is an extremely inconvenient range for design, operation and analysis of lifting surfaces, even in steady motion, because their properties are very sensitive to boundary layer separation. The moderate- to high-amplitude flapping motions, together with the complex surface geometry and mechanical properties of the wings themselves lead to yet further challenges. This talk will review some of the theoretical and practical approaches towards understanding and analyzing the aerodynamics of various types of bird flight, including some recent research results that suggest that this effort is far from complete.

  13. Migration strategy of a flight generalist, the Lesser Black-backed Gull Larus fuscus

    NARCIS (Netherlands)

    Klassen, R.H.G.; Ens, B.J.; Shamoun-Baranes, J.; Exo, K.M.; Bairlein, F.

    2012-01-01

    Migrating birds are believed to minimize the time spent on migration rather than energy. Birds seem to maximize migration speed in different ways as a noteworthy variation in migration strategies exists. We studied migration strategies of a flight mode and feeding generalist, the Lesser Black-backed

  14. 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.

  15. In-flight turbulence benefits soaring birds

    Science.gov (United States)

    Mallon, Julie M.; Bildstein, Keith L.; Katzner, Todd E.

    2016-01-01

    Birds use atmospheric updrafts to subsidize soaring flight. We observed highly variable soaring flight by Black Vultures (Coragyps atratus) and Turkey Vultures (Cathartes aura) in Virginia, USA, that was inconsistent with published descriptions of terrestrial avian flight. Birds engaging in this behavior regularly deviated vertically and horizontally from linear flight paths. We observed the soaring flight behavior of these 2 species to understand why they soar in this manner and when this behavior occurs. Vultures used this type of soaring mainly at low altitudes (birds because it permits continuous subsidized flight when other types of updraft are not available.

  16. 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.

  17. Endogenous timing factors in bird migration

    Science.gov (United States)

    Gwinner, E. G.

    1972-01-01

    Several species of warbler birds were observed in an effort to determine what initiates and terminates migration. Environmental and endogenous timing mechanisms were analyzed. The results indicate that endogenous stimuli are dominant factors for bird migration especially for long distances. It was concluded that environmental factors act as an assist mechanism.

  18. 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

  19. 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

  20. 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

  1. CONSEQUENCES OF WEIGHT DECREASE ON FLIGHT PERFORMANCE DURING MIGRATION

    NARCIS (Netherlands)

    VIDELER, JJ

    1995-01-01

    Migrating birds, flying nonstop over long distances, are substantially heavier at the start than at the end of their journey. Aerodynamic models predict that these birds would optimally have to fly faster in the beginning of their flight, and end at a slower speed. Energy expenditure would be

  2. Wild geese do not increase flight behaviour prior to migration.

    Science.gov (United States)

    Portugal, Steven J; Green, Jonathan A; White, Craig R; Guillemette, Magella; Butler, Patrick J

    2012-06-23

    Hypertrophy of the flight muscles is regularly observed in birds prior to long-distance migrations. We tested the hypothesis that a large migratory bird would increase flight behaviour prior to migration, in order to cause hypertrophy of the flight muscles, and upregulate key components of the aerobic metabolic pathways. Implantable data loggers were used to record year-round heart rate in six wild barnacle geese (Branta leucopsis), and the amount of time spent in flight each day was identified. Time in flight per day did not significantly increase prior to either the spring or the autumn migration, both between time periods prior to migration (5, 10 and 15 days), or when compared with a control period of low activity during winter. The lack of significant increase in flight prior to migration suggests that approximately 22 min per day is sufficient to maintain the flight muscles in condition for prolonged long-distance flight. This apparent lack of a requirement for increased flight activity prior to migration may be attributable to pre-migratory mass gains in the geese increasing workload during short flights, potentially prompting hypertrophy of the flight muscles.

  3. Factors influencing phototaxis in nocturnal migrating birds.

    Science.gov (United States)

    Zhao, Xuebing; Chen, Mingyan; Wu, Zhaolu; Wang, Zijiang

    2014-12-01

    Many migratory bird species fly during the night (nocturnal migrants) and have been shown to display some phototaxis to artificial light. During 2006 to 2009, we investigated phototaxis in nocturnal migrants at Jinshan Yakou in Xinping County (N23°56', E101°30'; 2400 m above sea-level), and at the Niaowang Mountain in Funing County (N23°30', E105°35'; 1400 m above sea-level), both in the Yunnan Province of Southwest China. A total of 5069 birds, representing 129 species, were captured by mist-netting and artificial light. The extent of phototaxis effect on bird migration was examined during all four seasons, three phases of the moon, and under two weather conditions (mist and wind). Data were statistically analyzed to determine the extent to which these factors may impact phototaxis of nocturnal migrants. The results point to phototaxis in birds migrating in the spring and autumn, especially in the autumn. Furthermore, migrating birds were more readily attracted to artificial lights during nights with little moonlight, mist, and a headwind. Regardless of the initial orientation in which birds flew, either following the wind or against the wind, birds would always fly against the wind when flying towards the light. This study broadens our understanding of the nocturnal bird migration, potentially resulting in improved bird ringing practices, increased awareness, and better policies regarding bird protection.

  4. 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.

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

    Science.gov (United States)

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

    2009-03-01

    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.

  6. 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

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

    Energy Technology Data Exchange (ETDEWEB)

    Hedenstroem, Anders; Johansson, L Christoffer [Department of Theoretical Ecology, Ecology Building, SE-223 62 Lund (Sweden); Spedding, Geoffrey R [Department of Aerospace and Mechanical Engineering, University of Southern California, Los Angeles, CA 90098-1191 (United States)], E-mail: anders.hedenstrom@teorekol.lu.se

    2009-03-01

    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.

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

    OpenAIRE

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

    2018-01-01

    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 ...

  9. ON CORRELATING BIRD MIGRATION TRAJECTORY WITH CLIMATE CHANGES

    OpenAIRE

    Oleinik, Janaina; de Macedo, Jose Antonio Fernandes; Yuanjian, Wang Zufferey

    2009-01-01

    Climate changes are expected to affect bird migration in several aspects including timing changes, breeding and migration orientation. The correlation analysis of several climate conditions (e.g. temperature, wind, humidity, etc) and bird migration trajectory is the key for explaining bird behavior during migration. Moreover, the resulting correlation can be used for predicting new bird behavior according to climate changes. In this paper we propose an integrated solution for correlating bird...

  10. Carrying large fuel loads during sustained bird flight is cheaper than expected

    NARCIS (Netherlands)

    Kvist, A; Lindström, A; Green, M; Piersma, T.; Visser, G.H.

    2001-01-01

    Birds on migration alternate between consuming fuel stores during flights and accumulating fuel stores during stopovers. The optimal timing and length of flights and stopovers for successful migration depend heavily on the extra metabolic power input (fuel use) required to carry the fuel stores

  11. Flight speeds among bird species: allometric and phylogenetic effects.

    Directory of Open Access Journals (Sweden)

    Thomas Alerstam

    2007-08-01

    Full Text Available Flight speed is expected to increase with mass and wing loading among flying animals and aircraft for fundamental aerodynamic reasons. Assuming geometrical and dynamical similarity, cruising flight speed is predicted to vary as (body mass(1/6 and (wing loading(1/2 among bird species. To test these scaling rules and the general importance of mass and wing loading for bird flight speeds, we used tracking radar to measure flapping flight speeds of individuals or flocks of migrating birds visually identified to species as well as their altitude and winds at the altitudes where the birds were flying. Equivalent airspeeds (airspeeds corrected to sea level air density, Ue of 138 species, ranging 0.01-10 kg in mass, were analysed in relation to biometry and phylogeny. Scaling exponents in relation to mass and wing loading were significantly smaller than predicted (about 0.12 and 0.32, respectively, with similar results for analyses based on species and independent phylogenetic contrasts. These low scaling exponents may be the result of evolutionary restrictions on bird flight-speed range, counteracting too slow flight speeds among species with low wing loading and too fast speeds among species with high wing loading. This compression of speed range is partly attained through geometric differences, with aspect ratio showing a positive relationship with body mass and wing loading, but additional factors are required to fully explain the small scaling exponent of Ue in relation to wing loading. Furthermore, mass and wing loading accounted for only a limited proportion of the variation in Ue. Phylogeny was a powerful factor, in combination with wing loading, to account for the variation in Ue. These results demonstrate that functional flight adaptations and constraints associated with different evolutionary lineages have an important influence on cruising flapping flight speed that goes beyond the general aerodynamic scaling effects of mass and wing loading.

  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. 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.

  14. Anticipatory Manoeuvres in Bird Flight

    Science.gov (United States)

    Vo, Hong D.; Schiffner, Ingo; Srinivasan, Mandyam V.

    2016-01-01

    It is essential for birds to be agile and aware of their immediate environment, especially when flying through dense foliage. To investigate the type of visual signals and strategies used by birds while negotiating cluttered environments, we presented budgerigars with vertically oriented apertures of different widths. We find that, when flying through narrow apertures, birds execute their maneuvers in an anticipatory fashion, with wing closures, if necessary, occurring well in advance of the aperture. When passing through an aperture that is narrower than the wingspan, the birds close their wings at a specific, constant distance before the aperture, which is independent of aperture width. In these cases, the birds also fly significantly higher, possibly pre-compensating for the drop in altitude. The speed of approach is largely constant, and independent of the width of the aperture. The constancy of the approach speed suggests a simple means by which optic flow can be used to gauge the distance and width of the aperture, and guide wing closure. PMID:27270506

  15. Anticipatory Manoeuvres in Bird Flight.

    Science.gov (United States)

    Vo, Hong D; Schiffner, Ingo; Srinivasan, Mandyam V

    2016-06-08

    It is essential for birds to be agile and aware of their immediate environment, especially when flying through dense foliage. To investigate the type of visual signals and strategies used by birds while negotiating cluttered environments, we presented budgerigars with vertically oriented apertures of different widths. We find that, when flying through narrow apertures, birds execute their maneuvers in an anticipatory fashion, with wing closures, if necessary, occurring well in advance of the aperture. When passing through an aperture that is narrower than the wingspan, the birds close their wings at a specific, constant distance before the aperture, which is independent of aperture width. In these cases, the birds also fly significantly higher, possibly pre-compensating for the drop in altitude. The speed of approach is largely constant, and independent of the width of the aperture. The constancy of the approach speed suggests a simple means by which optic flow can be used to gauge the distance and width of the aperture, and guide wing closure.

  16. Tracking radar studies of bird migration

    Science.gov (United States)

    Williams, T. C.; Williams, J. M.; Teal, J. M.; Kanwisher, J. W.

    1972-01-01

    The application of tracking radar for determining the flight paths of migratory birds is discussed. The effects produced by various meteorological parameters are described. Samples of radar scope presentations obtained during tracking studies are presented. The characteristics of the radars and their limitations are examined.

  17. Contributions of endocrinology to the migration life history of birds.

    Science.gov (United States)

    Cornelius, J M; Boswell, T; Jenni-Eiermann, S; Breuner, C W; Ramenofsky, M

    2013-09-01

    Migration is a key life cycle stage in nearly 2000 species of birds and is a greatly appreciated phenomenon in both cultural and academic arenas. Despite a long research tradition concerning many aspects of migration, investigations of hormonal contributions to migratory physiology and behavior are more limited and represent a comparatively young research field. We review advances in our understanding of the hormonal mechanisms of migration with particular emphasis on the sub-stages of the migration life history: development, departure, flight and arrival. These sub-stages vary widely in their behavioral, ecological and physiological contexts and, as such, should be given appropriate individual consideration. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Seasonal changes in the altitudinal distribution of nocturnally migrating birds during autumn migration.

    Science.gov (United States)

    La Sorte, Frank A; Hochachka, Wesley M; Farnsworth, Andrew; Sheldon, Daniel; Van Doren, Benjamin M; Fink, Daniel; Kelling, Steve

    2015-12-01

    Wind plays a significant role in the flight altitudes selected by nocturnally migrating birds. At mid-latitudes in the Northern Hemisphere, atmospheric conditions are dictated by the polar-front jet stream, whose amplitude increases in the autumn. One consequence for migratory birds is that the region's prevailing westerly winds become progressively stronger at higher migration altitudes. We expect this seasonality in wind speed to result in migrants occupying progressively lower flight altitudes, which we test using density estimates of nocturnal migrants at 100 m altitudinal intervals from 12 weather surveillance radar stations located in the northeastern USA. Contrary to our expectations, median migration altitudes deviated little across the season, and the variance was lower during the middle of the season and higher during the beginning and especially the end of the season. Early-season migrants included small- to intermediate-sized long-distance migrants in the orders Charadriiformes and Passeriformes, and late-season migrants included large-bodied and intermediate-distance migrants in the order Anseriformes. Therefore, seasonality in the composition of migratory species, and related variation in migration strategies and behaviours, resulted in a convex-concave bounded distribution of migration altitudes. Our results provide a basis for assessing the implications for migratory bird populations of changes in mid-latitude atmospheric conditions probably occurring under global climate change.

  19. Bird Flight and Satish Dhawan: Some Thoughts

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 8; Issue 10. Bird Flight and Satish Dhawan: Some Thoughts. K R Y Simha. General Article Volume 8 Issue 10 October 2003 pp 31-39. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/008/10/0031-0039 ...

  20. Empirical evidence for differential organ reductions during trans-oceanic bird flight

    NARCIS (Netherlands)

    Battley, PF; Piersma, T; Dietz, MW; Tang, SX; Dekinga, A; Hulsman, K

    2000-01-01

    Since the early 1960s it has been held that migrating birds deposit and use only fat as fuel during migratory flight, with the non-fat portion of the body remaining homeostatic. Recent evidence from field studies has shown large changes in organ sizes in fuelling birds, and theory on fuel use

  1. High-intensity urban light installation dramatically alters nocturnal bird migration.

    Science.gov (United States)

    Van Doren, Benjamin M; Horton, Kyle G; Dokter, Adriaan M; Klinck, Holger; Elbin, Susan B; Farnsworth, Andrew

    2017-10-17

    Billions of nocturnally migrating birds move through increasingly photopolluted skies, relying on cues for navigation and orientation that artificial light at night (ALAN) can impair. However, no studies have quantified avian responses to powerful ground-based light sources in urban areas. We studied effects of ALAN on migrating birds by monitoring the beams of the National September 11 Memorial & Museum's "Tribute in Light" in New York, quantifying behavioral responses with radar and acoustic sensors and modeling disorientation and attraction with simulations. This single light source induced significant behavioral alterations in birds, even in good visibility conditions, in this heavily photopolluted environment, and to altitudes up to 4 km. We estimate that the installation influenced ≈1.1 million birds during our study period of 7 d over 7 y. When the installation was illuminated, birds aggregated in high densities, decreased flight speeds, followed circular flight paths, and vocalized frequently. Simulations revealed a high probability of disorientation and subsequent attraction for nearby birds, and bird densities near the installation exceeded magnitudes 20 times greater than surrounding baseline densities during each year's observations. However, behavioral disruptions disappeared when lights were extinguished, suggesting that selective removal of light during nights with substantial bird migration is a viable strategy for minimizing potentially fatal interactions among ALAN, structures, and birds. Our results also highlight the value of additional studies describing behavioral patterns of nocturnally migrating birds in powerful lights in urban areas as well as conservation implications for such lighting installations.

  2. Differences in speed and duration of bird migration between spring and autumn.

    Science.gov (United States)

    Nilsson, Cecilia; Klaassen, Raymond H G; Alerstam, Thomas

    2013-06-01

    It has been suggested that birds migrate faster in spring than in autumn because of competition for arrival order at breeding grounds and environmental factors such as increased daylight. Investigating spring and autumn migration performances is important for understanding ecological and evolutionary constraints in the timing and speed of migration. We compiled measurements from tracking studies and found a consistent predominance of cases showing higher speeds and shorter durations during spring compared to autumn, in terms of flight speeds (airspeed, ground speed, daily travel speed), stopover duration, and total speed and duration of migration. Seasonal differences in flight speeds were generally smaller than those in stopover durations and total speed/duration of migration, indicating that rates of foraging and fuel deposition were more important than flight speed in accounting for differences in overall migration performance. Still, the seasonal differences in flight speeds provide important support for time selection in spring migration.

  3. Individuality in bird migration: routes and timing.

    Science.gov (United States)

    Vardanis, Yannis; Klaassen, Raymond H G; Strandberg, Roine; Alerstam, Thomas

    2011-08-23

    The exploration of animal migration has entered a new era with individual-based tracking during multiple years. Here, we investigated repeated migratory journeys of a long-distance migrating bird, the marsh harrier Circus aeruginosus, in order to analyse the variation within and between individuals with respect to routes and timing. We found that there was a stronger individual repeatability in time than in space. Thus, the annual timing of migration varied much less between repeated journeys of the same individual than between different individuals, while there was considerable variation in the routes of the same individual on repeated journeys. The overall contrast in repeatability between time and space was unexpected and may be owing to strong endogenous control of timing, while short-term variation in environmental conditions (weather and habitat) might promote route flexibility. The individual variation in migration routes indicates that the birds navigate mainly by other means than detailed route recapitulation based on landmark recognition. This journal is © 2011 The Royal Society

  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. Influence of offshore windmills on migration birds in southeast coast of Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Pettersson, Jan [BirdWind, Faerjestaden (Sweden); Stalin, Thomas [GE Energy AB, Vaesteraas (Sweden)

    2003-06-01

    Up to 1,000,000 sea birds meets two offshore wind parks at Utgrunden and at Yttre Stengrund during their migration along the Swedish southeast coast. The sea birds reaction on these wind turbines are studied during spring and autumn migration since autumn 2000. The performed study shows that the sea birds recognise the wind turbines and change their flight route to either side of the wind park. Radar studies show that the sea birds have similar behaviour during night. In wintertime food-searching sea birds continue to be in the area with wind turbines. The results are promising and so far has no collision occurred during the observation of 800,000 sea birds.

  7. 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

  8. Space-Based Ornithology - Studying Bird Migration and Environmental Change in North America

    Science.gov (United States)

    Smith, James A.; Deppe, Jill L.

    2008-01-01

    Natural fluctuations in the availability of critical stopover sites coupled with anthropogenic destruction of wetlands, land-use change, and anticipated losses due to climate change present migratory birds with a formidable challenge. Space based technology in concert with bird migration modeling and geographical information analysis yields new opportunities to shed light on the distribution and movement of organisms on the planet and their sensitivity to human disturbances and environmental changes. At the NASA Goddard Space Flight Center, we are creating ecological forecasting tools for science and application users to address the consequences of loss of wetlands, flooding, drought or other natural disasters such as hurricanes on avian biodiversity and bird migration. We use an individual-based bird biophysical migration model, driven by remotely sensed land surface data, climate and hydrologic data, and biological field observations to study migratory bird responses to environmental change in North America. Simulation allows us to study bird migration across multiple scales and can be linked to mechanistic processes describing the time and energy budget states of migrating birds. We illustrate our approach by simulating the spring migration of pectoral sandpipers from the Gulf of Mexico to Alaska. Mean stopover length and trajectory patterns are consistent with field observations.

  9. A Flight Mechanics-Centric Review of Bird-Scale Flapping Flight

    OpenAIRE

    Paranjape, Aditya A.; Dorothy, Michael R.; Chung, Soon-Jo; Lee, Ki-D.

    2012-01-01

    This paper reviews the flight mechanics and control of birds and bird-size aircraft. It is intended to fill a niche in the current survey literature which focuses primarily on the aerodynamics, flight dynamics and control of insect scale flight. We review the flight mechanics from first principles and summarize some recent results on the stability and control of birds and bird-scale aircraft. Birds spend a considerable portion of their flight in the gliding (i.e., non-flapping) phase. Therefo...

  10. From a Bird's Eye View: An Interdisciplinary Approach to Migration

    Science.gov (United States)

    Benson, Juliann

    2007-01-01

    Inspiring students to learn about birds can be a daunting task--students see birds just about every day and often don't think twice about them. The activity described here is designed to excite students to "become" birds. Students are asked to create a model and tell the life story of a bird by mapping its migration pattern. (Contains 6 figures, 6…

  11. Where in the air? Aerial habitat use of nocturnally migrating birds.

    Science.gov (United States)

    Horton, Kyle G; Van Doren, Benjamin M; Stepanian, Phillip M; Farnsworth, Andrew; Kelly, Jeffrey F

    2016-11-01

    The lower atmosphere (i.e. aerosphere) is critical habitat for migrant birds. This habitat is vast and little is known about the spatio-temporal patterns of distribution and abundance of migrants in it. Increased human encroachment into the aerosphere makes understanding where and when migratory birds use this airspace a key to reducing human-wildlife conflicts. We use weather surveillance radar to describe large-scale height distributions of nocturnally migrating birds and interpret these distributions as aggregate habitat selection behaviours of individual birds. As such, we detail wind cues that influence selection of flight heights. Using six radars in the eastern USA during the spring (2013-2015) and autumn (2013 and 2014), we found migrants tended to adjust their heights according to favourable wind profit. We found that migrants' flight altitudes correlated most closely with the altitude of maximum wind profit; however, absolute differences in flight heights and height of maximum wind profit were large. Migrants tended to fly slightly higher at inland sites compared with coastal sites during spring, but not during autumn. Migration activity was greater at coastal sites during autumn, but not during spring. This characterization of bird migration represents a critical advance in our understanding of migrant distributions in flight and a new window into habitat selection behaviours. © 2016 The Author(s).

  12. PRELIMINARY RESULTS OF RADAR OBSERVATION OF NOCTURNAL BIRD MIGRATION IN ISRAEL

    Directory of Open Access Journals (Sweden)

    Matsyura A.V.

    2011-11-01

    Full Text Available The results of radar-tracking supervisions over the night migration in Israel are submitted. The determination of flight altitudes, flight speeds, heights of maximum birds’ concentration, and migratory directions was performed. The average flight altitudes of night migration were 985 m in autumn and 1465 m in spring of 1998-2000, maximum flight altitudes were 2068 m and 2655 m correspondingly. The mean track direction of the night bird migration is 183° in spring and 6° in autumn. The migration of waterfowl over the Mediterranean Sea in the low altitude band was registered. Their average headings differ from the general migratory path, averaging 135° in autumn and 315° in spring. The average birds’ groundspeed was 14 m/s (50 km/h in spring and 13 m/s (47 km/h in autumn.

  13. Carrying large fuel loads during sustained bird flight is cheaper than expected.

    Science.gov (United States)

    Kvist, A; Lindström A; Green, M; Piersma, T; Visser, G H

    2001-10-18

    Birds on migration alternate between consuming fuel stores during flights and accumulating fuel stores during stopovers. The optimal timing and length of flights and stopovers for successful migration depend heavily on the extra metabolic power input (fuel use) required to carry the fuel stores during flight. The effect of large fuel loads on metabolic power input has never been empirically determined. We measured the total metabolic power input of a long-distance migrant, the red knot (Calidris canutus), flying for 6 to 10 h in a wind tunnel, using the doubly labelled water technique. Here we show that total metabolic power input increased with fuel load, but proportionally less than the predicted mechanical power output from the flight muscles. The most likely explanation is that the efficiency with which metabolic power input is converted into mechanical output by the flight muscles increases with fuel load. This will influence current models of bird flight and bird migration. It may also help to explain why some shorebirds, despite the high metabolic power input required to fly, routinely make nonstop flights of 4,000 km longer.

  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. 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.

  16. The Study of Bird Migration by Radar . Part 1: The Technical Basis*

    Science.gov (United States)

    Bruderer, Bruno

    Since the 1960s radar has been an established research tool in bird migration studies. Radar informs us about the actual course of migration under various environmental conditions: it covers wide distances, is independent of light and reasonably independent of weather, provides data on migratory intensity, flight paths and with special equipment the wing-beat pattern of birds. It thus fills an important gap left by other methods such as visual and auditory observations, laboratory research, trapping, and ringing studies. For an appropriate use of the sophisticated tool, however, it is important to know its capabilities and limitations.

  17. Influence of weather conditions on the flight of migrating black storks

    OpenAIRE

    Chevallier, D.; Handrich, Y.; Georges, J.-Y.; Baillon, F.; Brossault, P.; Aurouet, A.; Le Maho, Y.; Massemin, S.

    2010-01-01

    This study tested the potential influence of meteorological parameters (temperature, humidity, wind direction, thermal convection) on different migration characteristics (namely flight speed, altitude and direction and daily distance) in 16 black storks (Ciconia nigra). The birds were tracked by satellite during their entire autumnal and spring migration, from 1998 to 2006. Our data reveal that during their 27-day-long migration between Europe and Africa (mean distance of 4100 km), the period...

  18. Convergent patterns of long-distance nocturnal migration in noctuid moths and passerine birds.

    Science.gov (United States)

    Alerstam, Thomas; Chapman, Jason W; Bäckman, Johan; Smith, Alan D; Karlsson, Håkan; Nilsson, Cecilia; Reynolds, Don R; Klaassen, Raymond H G; Hill, Jane K

    2011-10-22

    Vast numbers of insects and passerines achieve long-distance migrations between summer and winter locations by undertaking high-altitude nocturnal flights. Insects such as noctuid moths fly relatively slowly in relation to the surrounding air, with airspeeds approximately one-third of that of passerines. Thus, it has been widely assumed that windborne insect migrants will have comparatively little control over their migration speed and direction compared with migrant birds. We used radar to carry out the first comparative analyses of the flight behaviour and migratory strategies of insects and birds under nearly equivalent natural conditions. Contrary to expectations, noctuid moths attained almost identical ground speeds and travel directions compared with passerines, despite their very different flight powers and sensory capacities. Moths achieved fast travel speeds in seasonally appropriate migration directions by exploiting favourably directed winds and selecting flight altitudes that coincided with the fastest air streams. By contrast, passerines were less selective of wind conditions, relying on self-powered flight in their seasonally preferred direction, often with little or no tailwind assistance. Our results demonstrate that noctuid moths and passerines show contrasting risk-prone and risk-averse migratory strategies in relation to wind. Comparative studies of the flight behaviours of distantly related taxa are critically important for understanding the evolution of animal migration strategies.

  19. Quality assessment of weather radar wind profiles during bird migration

    NARCIS (Netherlands)

    Holleman, I.; van Gasteren, H.; Bouten, W.

    2008-01-01

    Wind profiles from an operational C-band Doppler radar have been combined with data from a bird tracking radar to assess the wind profile quality during bird migration. The weather radar wind profiles (WRWPs) are retrieved using the well-known volume velocity processing (VVP) technique. The X-band

  20. Influence of weather conditions on the flight of migrating black storks.

    Science.gov (United States)

    Chevallier, D; Handrich, Y; Georges, J-Y; Baillon, F; Brossault, P; Aurouet, A; Le Maho, Y; Massemin, S

    2010-09-22

    This study tested the potential influence of meteorological parameters (temperature, humidity, wind direction, thermal convection) on different migration characteristics (namely flight speed, altitude and direction and daily distance) in 16 black storks (Ciconia nigra). The birds were tracked by satellite during their entire autumnal and spring migration, from 1998 to 2006. Our data reveal that during their 27-day-long migration between Europe and Africa (mean distance of 4100 km), the periods of maximum flight activity corresponded to periods of maximum thermal energy, underlining the importance of atmospheric thermal convection in the migratory flight of the black stork. In some cases, tailwind was recorded at the same altitude and position as the birds, and was associated with a significant rise in flight speed, but wind often produced a side azimuth along the birds' migratory route. Whatever the season, the distance travelled daily was on average shorter in Europe than in Africa, with values of 200 and 270 km d(-1), respectively. The fastest instantaneous flight speeds of up to 112 km h(-1) were also observed above Africa. This observation confirms the hypothesis of thermal-dependant flight behaviour, and also reveals differences in flight costs between Europe and Africa. Furthermore, differences in food availability, a crucial factor for black storks during their flight between Europe and Africa, may also contribute to the above-mentioned shift in daily flight speeds.

  1. 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…

  2. Why migrate during the day: a comparative analysis of North American birds.

    Science.gov (United States)

    Beauchamp, G

    2011-09-01

    Migration can take place primarily during the day or at night, or during both depending on the species. Why the timing of migration varies among species has been the object of much research but the underlying ecological processes are still unclear. Proximally, migration timing may be influenced by the timing of other activities or may be more prevalent in species that migrate over long distances. Adaptive scenarios emphasize the reduction in flight costs at night especially in smaller species and the advantages of travelling in groups during the day to locate staging sites more efficiently. I used phylogenetic independent contrasts to examine these hypotheses in all North American nesting birds. I uncovered 24 evolutionary transitions in migration timing, most of which involved a switch from nocturnal to diurnal migration. Few of these transitions involved a concomitant change in the timing of foraging habits or migration distance. However, species in diurnal clades were larger, travelled in larger flocks and were generally more sociable than their nocturnal counterparts. The results support the hypotheses that a reduction in flight costs and the ability to pool information from companions are associated with migration timing in North American bird species. © 2011 The Author. Journal of Evolutionary Biology © 2011 European Society For Evolutionary Biology.

  3. Frigate birds track atmospheric conditions over months-long transoceanic flights.

    Science.gov (United States)

    Weimerskirch, Henri; Bishop, Charles; Jeanniard-du-Dot, Tiphaine; Prudor, Aurélien; Sachs, Gottfried

    2016-07-01

    Understanding how animals respond to atmospheric conditions across space is critical for understanding the evolution of flight strategies and long-distance migrations. We studied the three-dimensional movements and energetics of great frigate birds (Fregata minor) and showed that they can stay aloft for months during transoceanic flights. To do this, birds track the edge of the doldrums to take advantage of favorable winds and strong convection. Locally, they use a roller-coaster flight, relying on thermals and wind to soar within a 50- to 600-meter altitude band under cumulus clouds and then glide over kilometers at low energy costs. To deal with the local scarcity of clouds and gain longer gliding distances, birds regularly soar inside cumulus clouds to use their strong updraft, and they can reach altitudes of 4000 meters, where freezing conditions occur. Copyright © 2016, American Association for the Advancement of Science.

  4. Phenology and the changing pattern of bird migration in Britain

    Science.gov (United States)

    Sparks, T. H.

    Britain has a huge mass of data on the timing of bird migration, although much of this remains in a form that is inaccessible for immediate scientific study. In this paper, I undertake a preliminary examination of data from a number of historical and current sources. Among these are the Marsham family records from Norfolk, dating back to 1736, and post-World War II records from coastal bird observatories. The majority of the examined time series displayed a negative relationship to temperature indicating a tendency for the earlier arrival of the studied birds in warmer springs. In addition to temperature effects, trends through time and some sampling effects (through population size) have become apparent. Identification and curation of data sources and further analysis is still required to produce a clearer picture of climate effects on bird migration timing and on subsequent bird population dynamics.

  5. Aspects regarding the limicoline birds' migration in the IBA

    Directory of Open Access Journals (Sweden)

    MULLER Johanna Walle

    2006-09-01

    Full Text Available The IBA “Jijia and Miletin ponds” (code 014 is situated at 40 km north-west from Iaşi city, around the confluence point of Miletin and Jijia Rivers, forming Vlădeni wetland. During the migration periods – in spring and autumn – we can count in Vlădeni wetland territory large flocks of limicoline birds (thousands exemplars, being represented 28 species; some of them are very rare in this part of Romania: Pluvialis apricaria, Pluvialis squatarola, Gallinago media, Lymnocryptes minimus, Arenaria interpres or Limosa lapponica. During the spring migration, but also during the autumn migration, we recorded 25 species, three species being different from a season of migration to other. During whole migration period, there are two super-dominant species Vanellus vanellus and Limosa limosa. We notice the irregular presence autumn migration of Gallinago media. In December are still present 5 species of limicoline birds.

  6. Timing of arrival from spring migration is associated with flight performance in the migratory barn swallow.

    Science.gov (United States)

    Matyjasiak, Piotr

    2013-01-01

    Timing of arrival at the breeding grounds by migratory birds affects their mating success and access to superior resources, thus being a major factor associated with fitness. Much empirical work has been devoted to investigate the condition dependence of arrival sequence of migrants and characteristics of individuals that influence arrival time from migration. Surprisingly, there are no studies examining the relationship between flight performance of individual birds and their arrival time. I investigated the relative importance of direct effects of short-term flight performance, age, body condition and the degree of sexual ornamentation (tail length) on timing of spring arrival in the barn swallow (Hirundo rustica), a long-distance trans-equatorial passerine migrant. I evaluated short-term flight performance (a composite variable comprising flight manoeuvrability, velocity and acceleration) in a standardised manner using flight tunnels. Short-term flight performance was a significant and important predictor of spring arrival date. Furthermore, locomotion predicted arrival date of individual birds independently of morphological variables-the degree of sexual ornamentation (the length of the tail) and wing aspect ratio and body condition. I discuss the possible role short-term flight performance may have in determining migratory performance. This is the first time flight performance has been shown to be associated with timing of arrival from migration in a migratory bird.

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

    Science.gov (United States)

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

    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 to play a major role in controlling physiological traits in migratory birds during flight. However, results from field studies are partially equivocal, not least because data from birds during endurance flight are hard to get and present mostly a momentary shot. A wind-tunnel experiment offered the possibility to measure repeatedly under controlled conditions the effect of long flights on the stress hormone corticosterone. In a long-distance migrating shorebird, the red knot Calidris canutus, we measured plasma concentrations of corticosterone within 3 min and after a restraint time of 30 min directly after 2h and 10h non-stop flights, respectively, and during rest. Baseline corticosterone levels were unchanged directly after the flights, indicating that endurance flight did not affect corticosterone levels. The adrenocortical response to restraint showed the typical rise in birds during rest, while birds after a 2 or 10h flight substantially decreased plasma corticosterone concentrations. We suggest that the negative adrenocortical response to restraint after flight is part of the mechanism to reduce the proteolytic effect of corticosterone to save muscle protein and to avoid muscle damaging effects.

  8. Timing of arrival from spring migration is associated with flight performance in the migratory barn swallow

    OpenAIRE

    Matyjasiak, Piotr

    2012-01-01

    Timing of arrival at the breeding grounds by migratory birds affects their mating success and access to superior resources, thus being a major factor associated with fitness. Much empirical work has been devoted to investigate the condition dependence of arrival sequence of migrants and characteristics of individuals that influence arrival time from migration. Surprisingly, there are no studies examining the relationship between flight performance of individual birds and their arrival time. I...

  9. Evidence that birds sleep in mid-flight.

    Science.gov (United States)

    Rattenborg, Niels C; Voirin, Bryson; Cruz, Sebastian M; Tisdale, Ryan; Dell'Omo, Giacomo; Lipp, Hans-Peter; Wikelski, Martin; Vyssotski, Alexei L

    2016-08-03

    Many birds fly non-stop for days or longer, but do they sleep in flight and if so, how? It is commonly assumed that flying birds maintain environmental awareness and aerodynamic control by sleeping with only one eye closed and one cerebral hemisphere at a time. However, sleep has never been demonstrated in flying birds. Here, using electroencephalogram recordings of great frigatebirds (Fregata minor) flying over the ocean for up to 10 days, we show that they can sleep with either one hemisphere at a time or both hemispheres simultaneously. Also unexpectedly, frigatebirds sleep for only 0.69 h d(-1) (7.4% of the time spent sleeping on land), indicating that ecological demands for attention usually exceed the attention afforded by sleeping unihemispherically. In addition to establishing that birds can sleep in flight, our results challenge the view that they sustain prolonged flights by obtaining normal amounts of sleep on the wing.

  10. The evolution of bird migration--a synthesis.

    Science.gov (United States)

    Salewski, Volker; Bruderer, Bruno

    2007-04-01

    We approach the problem of the evolution of bird migration by asking whether migration evolves towards new breeding areas or towards survival areas in the non-breeding season. Thus, we avoid the ambiguity of the usually discussed "southern-home-theory" or "northern-home-theory". We argue that migration evolved in birds that spread to seasonal habitats through gradual dispersal to enhance survival during the non-breeding season; this in contrast to the alternative idea suggesting that migration evolved towards new breeding areas to increase reproductive success. Our synthesis is based on the threshold model explaining how migratory traits can change rapidly through microevolutionary processes. Our model brings former theories together and explains how bird migration, with the appropriate direction and time program, evolves through selection after genetically non-directed events such as dispersal and colonization. The model does not need the former untested assumptions such as competition as a reason for migration and for the disappearance of sedentary populations or higher reproductive success in temperate breeding areas. Our theory offers answers to questions such as how birds with a southern origin may gradually reach northern latitudes, why migration routes may follow historical expansion routes and why birds leave an area for the non-breeding season and move back instead of breeding on their wintering grounds. The theory proposes gradual change through selection and not sudden changes such as long distance dispersal or mutations and can be applied to migration at all latitudes and in all directions. The scenario provides a reasonable concept to understand most of the existing migratory phenomena on the basis of the ecology and genetics of migratory behaviour.

  11. Convergence of broad-scale migration strategies in terrestrial birds.

    Science.gov (United States)

    La Sorte, Frank A; Fink, Daniel; Hochachka, Wesley M; Kelling, Steve

    2016-01-27

    Migration is a common strategy used by birds that breed in seasonal environments. Selection for greater migration efficiency is likely to be stronger for terrestrial species whose migration strategies require non-stop transoceanic crossings. If multiple species use the same transoceanic flyway, then we expect the migration strategies of these species to converge geographically towards the most optimal solution. We test this by examining population-level migration trajectories within the Western Hemisphere for 118 migratory species using occurrence information from eBird. Geographical convergence of migration strategies was evident within specific terrestrial regions where geomorphological features such as mountains or isthmuses constrained overland migration. Convergence was also evident for transoceanic migrants that crossed the Gulf of Mexico or Atlantic Ocean. Here, annual population-level movements were characterized by clockwise looped trajectories, which resulted in faster but more circuitous journeys in the spring and more direct journeys in the autumn. These findings suggest that the unique constraints and requirements associated with transoceanic migration have promoted the spatial convergence of migration strategies. The combination of seasonal atmospheric and environmental conditions that has facilitated the use of similar broad-scale migration strategies may be especially prone to disruption under climate and land-use change. © 2016 The Author(s).

  12. Comparison of Visually Guided Flight in Insects and Birds

    Science.gov (United States)

    Altshuler, Douglas L.; Srinivasan, Mandyam V.

    2018-01-01

    Over the last half century, work with flies, bees, and moths have revealed a number of visual guidance strategies for controlling different aspects of flight. Some algorithms, such as the use of pattern velocity in forward flight, are employed by all insects studied so far, and are used to control multiple flight tasks such as regulation of speed, measurement of distance, and positioning through narrow passages. Although much attention has been devoted to long-range navigation and homing in birds, until recently, very little was known about how birds control flight in a moment-to-moment fashion. A bird that flies rapidly through dense foliage to land on a branch—as birds often do—engages in a veritable three-dimensional slalom, in which it has to continually dodge branches and leaves, and find, and possibly even plan a collision-free path to the goal in real time. Each mode of flight from take-off to goal could potentially involve a different visual guidance algorithm. Here, we briefly review strategies for visual guidance of flight in insects, synthesize recent work from short-range visual guidance in birds, and offer a general comparison between the two groups of organisms. PMID:29615852

  13. Comparison of Visually Guided Flight in Insects and Birds

    Directory of Open Access Journals (Sweden)

    Douglas L. Altshuler

    2018-03-01

    Full Text Available Over the last half century, work with flies, bees, and moths have revealed a number of visual guidance strategies for controlling different aspects of flight. Some algorithms, such as the use of pattern velocity in forward flight, are employed by all insects studied so far, and are used to control multiple flight tasks such as regulation of speed, measurement of distance, and positioning through narrow passages. Although much attention has been devoted to long-range navigation and homing in birds, until recently, very little was known about how birds control flight in a moment-to-moment fashion. A bird that flies rapidly through dense foliage to land on a branch—as birds often do—engages in a veritable three-dimensional slalom, in which it has to continually dodge branches and leaves, and find, and possibly even plan a collision-free path to the goal in real time. Each mode of flight from take-off to goal could potentially involve a different visual guidance algorithm. Here, we briefly review strategies for visual guidance of flight in insects, synthesize recent work from short-range visual guidance in birds, and offer a general comparison between the two groups of organisms.

  14. Comparison of Visually Guided Flight in Insects and Birds.

    Science.gov (United States)

    Altshuler, Douglas L; Srinivasan, Mandyam V

    2018-01-01

    Over the last half century, work with flies, bees, and moths have revealed a number of visual guidance strategies for controlling different aspects of flight. Some algorithms, such as the use of pattern velocity in forward flight, are employed by all insects studied so far, and are used to control multiple flight tasks such as regulation of speed, measurement of distance, and positioning through narrow passages. Although much attention has been devoted to long-range navigation and homing in birds, until recently, very little was known about how birds control flight in a moment-to-moment fashion. A bird that flies rapidly through dense foliage to land on a branch-as birds often do-engages in a veritable three-dimensional slalom, in which it has to continually dodge branches and leaves, and find, and possibly even plan a collision-free path to the goal in real time. Each mode of flight from take-off to goal could potentially involve a different visual guidance algorithm. Here, we briefly review strategies for visual guidance of flight in insects, synthesize recent work from short-range visual guidance in birds, and offer a general comparison between the two groups of organisms.

  15. The Algorithm of Habitat Discovery in Bird Migration

    Directory of Open Access Journals (Sweden)

    Wei Zhengzheng

    2017-01-01

    Full Text Available Bird migration has attracted an increasing attention. The study of habitats has played a vital role in the birds migratory. Previous researches, however, have encountered many problems, such as great limitations on research methods, low data utilization rate, statistics-focused and ineffective data processing and analysis methods. In this paper, the algorithm of habitat discovery is put forward by using computer’s data-mining technology based on the spatio-temporal characteristics of bird-watching data. First the algorithm detects and eliminates duplicate data to guarantee data standardization. Then density-based clustering algorithms are used to identify habitats where birds gathered. Finally the habitats of birds migratory are discovered.

  16. MODELLING OF THE ENERGY COSTS, FLIGHT SPEED, AND MIGRATORY DISTANCES OF THE MIGRATORY BIRDS

    Directory of Open Access Journals (Sweden)

    Matsyura M. V.

    2012-12-01

    Full Text Available The results of the preliminary analysis carried out by Flight software for White Stork and Pelican that migrate within the Mediterranean-Black Sea Migratory Route were presented. Obtained results practically coincide with experimental results and data of radar observations. Optimum speed allows the birds to fly with a higher grade soaring and shorter distance between the thermal flows. Time to find the next effective thermals (thermal flux is reduced by increasing the speed, which in turn reduces the average rise in thermal flows, increases the risk not to find appropriate thermal. Soaring birds reduce wingspan and wing area by bending the joints of the extremities at high speeds. This reduces profile resistance and increases the inductive reactance. Profile resistance increases and the inductive reactance decreases with increasing of bird speed. Under ideal conditions the birds try to find a position of wingspan, which reduces the difference between the values of profile and inductive resistance.

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

    Science.gov (United States)

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

    2011-02-07

    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 networks is still very limited. To start investigating these aspects we developed an individual-based simulation model that describes the local interactions between birds and their environment during their migratory flight, leading to emergent patterns at larger scales. The aim of our model is to identify likely decision rules with respect to thermal selection and navigation. After explaining the model, it is applied to analyse the migration of white storks (Ciconia ciconia) over part of its migration domain. A model base-run is accompanied by a sensitivity analysis. It appears that social interactions lead to the use of fewer thermals and slight increases in distance travelled. Possibilities for different model extensions and further model application are discussed. Copyright © 2010 Elsevier Ltd. All rights reserved.

  18. 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.

  19. Spring migration of birds in relation to North Atlantic Oscillation

    Czech Academy of Sciences Publication Activity Database

    Hubálek, Zdeněk

    2003-01-01

    Roč. 52, č. 3 (2003), s. 287-298 ISSN 0139-7893 Institutional research plan: CEZ:AV0Z6093917 Keywords : bird migration * phenology * climate Subject RIV: EG - Zoology Impact factor: 0.494, year: 2003 http://www.ivb.cz/folia/52/3/287-298.pdf

  20. 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

  1. 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

  2. Protein loss during long-distance migratory flight in passerine birds: adaptation and constraint.

    Science.gov (United States)

    Schwilch, Regine; Grattarola, Alessandra; Spina, Fernando; Jenni, Lukas

    2002-03-01

    During long-distance flights, birds catabolize not only fat but also protein. Because there is no storage form of protein, protein catabolism entails a structural or functional loss. In this study, we investigated which organs were most reduced in lean mass during different phases of fat store loss and whether protein loss can be regarded as adaptive or as a constraint. Body and organ composition were analysed both during the autumn migration over continental Europe (sample from Switzerland) and after a long-distance flight over the Sahara and the Mediterranean Sea in spring (sample from Ventotene, Italy) in four species of passerine bird: pied flycatcher Ficedula hypoleuca, willow warbler Phylloscopus trochilus, garden warbler Sylvia borin and barn swallow Hirundo rustica. Large variations in protein mass occurred when long non-stop flights were performed. After a long-distance flight, birds showed a marked increase in net protein loss when fat stores were nearing depletion (analogous to the late phase of endurance fasting when the rate of protein catabolism is increased). When fat reserves were above approximately 5-10 %, protein was derived from all organs, but particularly from the breast muscles. When fat stores diminished further and protein catabolism increased, the mass of the digestive organs was reduced fastest. When the decrease in breast muscle mass during flight was regarded in terms of potential flight performance, it appeared that the use of breast muscle protein with decreasing body mass can be regarded as adaptive as long as fat stores did not reach a critical level. Below approximately 5-10 % body fat, however, protein loss reduced flight performance. This demonstrates that the phase of fasting (the size of the remaining fat stores) is an important condition for understanding the occurrence and effects of protein loss during endurance flights.

  3. Comparison of the cost of short flights in a nectarivorous and a non-nectarivorous bird

    NARCIS (Netherlands)

    Hambly, C; Pinshow, B; Wiersma, P; Verhulst, S; Piertney, SB; Harper, EJ; Speakman, [No Value; Speakman, J.R.

    2004-01-01

    Although most birds are accustomed to making short flights, particularly during foraging, the flight patterns during these short periods of activity differ between species. Nectarivorous; birds, in particular, often spend time hovering, while non-nectarivorous birds do not. The cost of short flights

  4. 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.

  5. High altitude bird migration at temperate latitudes: a synoptic perspective on wind assistance.

    Science.gov (United States)

    Dokter, Adriaan M; Shamoun-Baranes, Judy; Kemp, Michael U; Tijm, Sander; Holleman, Iwan

    2013-01-01

    At temperate latitudes the synoptic patterns of bird migration are strongly structured by the presence of cyclones and anticyclones, both in the horizontal and altitudinal dimensions. In certain synoptic conditions, birds may efficiently cross regions with opposing surface wind by choosing a higher flight altitude with more favourable wind. We observed migratory passerines at mid-latitudes that selected high altitude wind optima on particular nights, leading to the formation of structured migration layers at varying altitude up to 3 km. Using long-term vertical profiling of bird migration by C-band Doppler radar in the Netherlands, we find that such migration layers occur nearly exclusively during spring migration in the presence of a high-pressure system. A conceptual analytic framework providing insight into the synoptic patterns of wind assistance for migrants that includes the altitudinal dimension has so far been lacking. We present a simple model for a baroclinic atmosphere that relates vertical profiles of wind assistance to the pressure and temperature patterns occurring at temperate latitudes. We show how the magnitude and direction of the large scale horizontal temperature gradient affects the relative gain in wind assistance that migrants obtain through ascending. Temperature gradients typical for northerly high-pressure systems in spring are shown to cause high altitude wind optima in the easterly sectors of anticyclones, thereby explaining the frequent observations of high altitude migration in these synoptic conditions. Given the recurring synoptic arrangements of pressure systems across temperate continents, the opportunities for exploiting high altitude wind will differ between flyways, for example between easterly and westerly oceanic coasts.

  6. 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.

  7. Migration and parasitism : Habitat use, not migration distance, influences helminth species richness in Charadriiform birds

    NARCIS (Netherlands)

    Gutiérrez, Jorge S.; Rakhimberdiev, Eldar; Piersma, Theunis; Thieltges, David W.

    Aim: Habitat use and migration strategies of animals are often associated with spatial variation in parasite pressure, but how they relate to one another is not well understood. Here, we use a large dataset on helminth species richness of Charadriiform birds to test whether higher habitat diversity

  8. Migration and parasitism: habitat use, not migration distance, influences helminth species richness in Charadriiform birds

    NARCIS (Netherlands)

    Gutiérrez, J.S.; Rakhimberdiev, E.; Piersma, T.; Thieltges, D.W.

    2017-01-01

    Aim Habitat use and migration strategies of animals are often associated withspatial variation in parasite pressure, but how they relate to one another is notwell understood. Here, we use a large dataset on helminth species richness ofCharadriiform birds to test whether higher habitat diversity and

  9. 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

  10. Bird migration in south-western Romania: an analysis of ringing recoveries from Dolj county

    Directory of Open Access Journals (Sweden)

    RIDICHE Mirela-Sabina

    2017-12-01

    Full Text Available The present study concerns the bird species marked with rings in 21 countries (from Europe, Africa and Asia and that were recaptured in the SouhWest of Romania, more precisely in Dol county. The most came from Hungary (1 specimens, Russia ( specimens, and Ukraine ( specimens. The birds taken into consideration ( specimens belong to 22 species from halacocoa elecanus cticoa Aea iconia leais latalea Anas Atha otuni ulica hiloachus aus issa Stena aus genera. Some of them are kept in the patrimony of Museum of Oltenia, Craiova. The purpose of this study is to inform about the transcontinental bird migration and about some aspects regarding the traveled distance, flight speed, and longevity. In general, the ringed birds turned up in wetland areas nearby water courses, most of them being registred in the Danube Floodplain. In this contet, we want to emphasie the importance of wetland habitats, especially of the ones in the green corridor of Danube, as benefic shelters for stopover of migratory birds.

  11. Migration on Wings Aerodynamics and Energetics

    CERN Document Server

    Kantha, Lakshmi

    2012-01-01

    This book is an effort to explore the technical aspects associated with bird flight and migration on wings. After a short introduction on the birds migration, the book reviews the aerodynamics and Energetics of Flight and presents the calculation of the Migration Range. In addition, the authors explains aerodynamics of the formation flight and finally introduces great flight diagrams.

  12. 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

  13. Forward flight of birds revisited. Part 1: aerodynamics and performance.

    Science.gov (United States)

    Iosilevskii, G

    2014-10-01

    This paper is the first part of the two-part exposition, addressing performance and dynamic stability of birds. The aerodynamic model underlying the entire study is presented in this part. It exploits the simplicity of the lifting line approximation to furnish the forces and moments acting on a single wing in closed analytical forms. The accuracy of the model is corroborated by comparison with numerical simulations based on the vortex lattice method. Performance is studied both in tethered (as on a sting in a wind tunnel) and in free flights. Wing twist is identified as the main parameter affecting the flight performance-at high speeds, it improves efficiency, the rate of climb and the maximal level speed; at low speeds, it allows flying slower. It is demonstrated that, under most circumstances, the difference in performance between tethered and free flights is small.

  14. Timing avian long-distance migration: from internal clock mechanisms to global flights.

    Science.gov (United States)

    Åkesson, Susanne; Ilieva, Mihaela; Karagicheva, Julia; Rakhimberdiev, Eldar; Tomotani, Barbara; Helm, Barbara

    2017-11-19

    Migratory birds regularly perform impressive long-distance flights, which are timed relative to the anticipated environmental resources at destination areas that can be several thousand kilometres away. Timely migration requires diverse strategies and adaptations that involve an intricate interplay between internal clock mechanisms and environmental conditions across the annual cycle. Here we review what challenges birds face during long migrations to keep track of time as they exploit geographically distant resources that may vary in availability and predictability, and summarize the clock mechanisms that enable them to succeed. We examine the following challenges: departing in time for spring and autumn migration, in anticipation of future environmental conditions; using clocks on the move, for example for orientation, navigation and stopover; strategies of adhering to, or adjusting, the time programme while fitting their activities into an annual cycle; and keeping pace with a world of rapidly changing environments. We then elaborate these themes by case studies representing long-distance migrating birds with different annual movement patterns and associated adaptations of their circannual programmes. We discuss the current knowledge on how endogenous migration programmes interact with external information across the annual cycle, how components of annual cycle programmes encode topography and range expansions, and how fitness may be affected when mismatches between timing and environmental conditions occur. Lastly, we outline open questions and propose future research directions.This article is part of the themed issue 'Wild clocks: integrating chronobiology and ecology to understand timekeeping in free-living animals'. © 2017 The Author(s).

  15. 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

  16. 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

  17. Migration timing and its determinants for nocturnal migratory birds during autumn migration.

    Science.gov (United States)

    La Sorte, Frank A; Hochachka, Wesley M; Farnsworth, Andrew; Sheldon, Daniel; Fink, Daniel; Geevarghese, Jeffrey; Winner, Kevin; Van Doren, Benjamin M; Kelling, Steve

    2015-09-01

    1. Migration is a common strategy used by birds that breed in seasonal environments, and multiple environmental and biological factors determine the timing of migration. How these factors operate in combination during autumn migration, which is considered to be under weaker time constraints relative to spring migration, is not clear. 2. Here, we examine the patterns and determinants of migration timing for nocturnal migrants during autumn migration in the north-eastern USA using nocturnal reflectivity data from 12 weather surveillance radar stations and modelled diurnal probability of occurrence for 142 species of nocturnal migrants. We first model the capacity of seasonal atmospheric conditions (wind and precipitation) and ecological productivity (vegetation greenness) to predict autumn migration intensity. We then test predictions, formulated under optimal migration theory, on how migration timing should be related to assemblage-level estimates of body size and total migration distance within the context of dietary guild (insectivore and omnivore) and level of dietary plasticity during autumn migration. 3. Our results indicate seasonal declines in ecological productivity delineate the beginning and end of peak migration, whose intensity is best predicted by the velocity of winds at migration altitudes. Insectivorous migrants departed earlier in the season and, consistent with our predictions, large-bodied and long-distance insectivorous migrants departed the earliest. Contrary to our predictions, large-bodied and some long-distance omnivorous migrants departed later in the season, patterns that were replicated in part by insectivorous migrants that displayed dietary plasticity during autumn migration. 4. Our findings indicate migration timing in the region is dictated by optimality strategies, modified based on the breadth and flexibility of migrant's foraging diets, with declining ecological productivity defining possible resource thresholds during which

  18. Migrating Birds Optimization for the Seaside Problems at Maritime Container Terminals

    Directory of Open Access Journals (Sweden)

    Eduardo Lalla-Ruiz

    2015-01-01

    Full Text Available Sea freight transportation involves moving huge amounts of freights among maritime locations widely spaced by means of container vessels. The time required to serve container vessels is the most relevant indicator when assessing the competitiveness of a maritime container terminal. In this paper, two main logistic problems stemming from the transshipment of containers in the seaside of a maritime container terminal are addressed, namely, the Berth Allocation Problem aimed at allocating and scheduling incoming vessels into berthing positions along the quay and the Quay Crane Scheduling Problem, whose objective is to schedule the loading and unloading tasks associated with a container vessel. For solving them, two Migrating Birds Optimization (MBO approaches are proposed. The MBO is a recently proposed nature-inspired algorithm based on the V-formation flight of migrating birds. In this algorithm, a set of solutions of the problem at hand, called birds, cooperate among themselves during the search process by sharing information within a V-line formation. The computational experiments performed over well-known problem instances reported in the literature show that the performance of our proposed MBO approaches is highly competitive and presents a better performance in terms of running time than the best approximate approach proposed in the literature.

  19. Flight modes in migrating European bee-eaters: heart rate may indicate low metabolic rate during soaring and gliding.

    Directory of Open Access Journals (Sweden)

    Nir Sapir

    Full Text Available BACKGROUND: Many avian species soar and glide over land. Evidence from large birds (m(b>0.9 kg suggests that soaring-gliding is considerably cheaper in terms of energy than flapping flight, and costs about two to three times the basal metabolic rate (BMR. Yet, soaring-gliding is considered unfavorable for small birds because migration speed in small birds during soaring-gliding is believed to be lower than that of flapping flight. Nevertheless, several small bird species routinely soar and glide. METHODOLOGY/PRINCIPAL FINDINGS: To estimate the energetic cost of soaring-gliding flight in small birds, we measured heart beat frequencies of free-ranging migrating European bee-eaters (Merops apiaster, m(b∼55 g using radio telemetry, and established the relationship between heart beat frequency and metabolic rate (by indirect calorimetry in the laboratory. Heart beat frequency during sustained soaring-gliding was 2.2 to 2.5 times lower than during flapping flight, but similar to, and not significantly different from, that measured in resting birds. We estimated that soaring-gliding metabolic rate of European bee-eaters is about twice their basal metabolic rate (BMR, which is similar to the value estimated in the black-browed albatross Thalassarche (previously Diomedea melanophrys, m(b∼4 kg. We found that soaring-gliding migration speed is not significantly different from flapping migration speed. CONCLUSIONS/SIGNIFICANCE: We found no evidence that soaring-gliding speed is slower than flapping flight in bee-eaters, contradicting earlier estimates that implied a migration speed penalty for using soaring-gliding rather than flapping flight. Moreover, we suggest that small birds soar and glide during migration, breeding, dispersal, and other stages in their annual cycle because it may entail a low energy cost of transport. We propose that the energy cost of soaring-gliding may be proportional to BMR regardless of bird size, as theoretically deduced by

  20. Candidatus Neoehrlichia mikurensis in Ticks from Migrating Birds in Sweden.

    Science.gov (United States)

    Labbé Sandelin, Lisa; Tolf, Conny; Larsson, Sara; Wilhelmsson, Peter; Salaneck, Erik; Jaenson, Thomas G T; Lindgren, Per-Eric; Olsen, Björn; Waldenström, Jonas

    2015-01-01

    Candidatus Neoehrlichia mikurensis (CNM; family Anaplasmataceae) was recently recognized as a potential tick-borne human pathogen. The presence of CNM in mammals, in host-seeking Ixodes ticks and in ticks attached to mammals and birds has been reported recently. We investigated the presence of CNM in ornithophagous ticks from migrating birds. A total of 1,150 ticks (582 nymphs, 548 larvae, 18 undetermined ticks and two adult females) collected from 5,365 birds captured in south-eastern Sweden was screened for CNM by molecular methods. The birds represented 65 different species, of which 35 species were infested with one or more ticks. Based on a combination of morphological and molecular species identification, the majority of the ticks were identified as Ixodes ricinus. Samples were initially screened by real-time PCR targeting the CNM 16S rRNA gene, and confirmed by a second real-time PCR targeting the groEL gene. For positive samples, a 1260 base pair fragment of the 16S rRNA gene was sequenced. Based upon bacterial gene sequence identification, 2.1% (24/1150) of the analysed samples were CNM-positive. Twenty-two out of 24 CNM-positive ticks were molecularly identified as I. ricinus nymphs, and the remaining two were identified as I. ricinus based on morphology. The overall CNM prevalence in I. ricinus nymphs was 4.2%. None of the 548 tested larvae was positive. CNM-positive ticks were collected from 10 different bird species. The highest CNM-prevalences were recorded in nymphs collected from common redpoll (Carduelis flammea, 3/7), thrush nightingale (Luscinia luscinia, 2/29) and dunnock (Prunella modularis, 1/17). The 16S rRNA sequences obtained in this study were all identical to each other and to three previously reported European strains, two of which were obtained from humans. It is concluded that ornithophagous ticks may be infected with CNM and that birds most likely can disperse CNM-infected ticks over large geographical areas.

  1. Candidatus Neoehrlichia mikurensis in Ticks from Migrating Birds in Sweden.

    Directory of Open Access Journals (Sweden)

    Lisa Labbé Sandelin

    Full Text Available Candidatus Neoehrlichia mikurensis (CNM; family Anaplasmataceae was recently recognized as a potential tick-borne human pathogen. The presence of CNM in mammals, in host-seeking Ixodes ticks and in ticks attached to mammals and birds has been reported recently. We investigated the presence of CNM in ornithophagous ticks from migrating birds. A total of 1,150 ticks (582 nymphs, 548 larvae, 18 undetermined ticks and two adult females collected from 5,365 birds captured in south-eastern Sweden was screened for CNM by molecular methods. The birds represented 65 different species, of which 35 species were infested with one or more ticks. Based on a combination of morphological and molecular species identification, the majority of the ticks were identified as Ixodes ricinus. Samples were initially screened by real-time PCR targeting the CNM 16S rRNA gene, and confirmed by a second real-time PCR targeting the groEL gene. For positive samples, a 1260 base pair fragment of the 16S rRNA gene was sequenced. Based upon bacterial gene sequence identification, 2.1% (24/1150 of the analysed samples were CNM-positive. Twenty-two out of 24 CNM-positive ticks were molecularly identified as I. ricinus nymphs, and the remaining two were identified as I. ricinus based on morphology. The overall CNM prevalence in I. ricinus nymphs was 4.2%. None of the 548 tested larvae was positive. CNM-positive ticks were collected from 10 different bird species. The highest CNM-prevalences were recorded in nymphs collected from common redpoll (Carduelis flammea, 3/7, thrush nightingale (Luscinia luscinia, 2/29 and dunnock (Prunella modularis, 1/17. The 16S rRNA sequences obtained in this study were all identical to each other and to three previously reported European strains, two of which were obtained from humans. It is concluded that ornithophagous ticks may be infected with CNM and that birds most likely can disperse CNM-infected ticks over large geographical areas.

  2. 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.

  3. 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.

  4. Thermal soaring flight of birds and unmanned aerial vehicles.

    Science.gov (United States)

    Akos, Zsuzsa; Nagy, Máté; Leven, Severin; Vicsek, Tamás

    2010-12-01

    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.

  5. Thermal soaring flight of birds and unmanned aerial vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Akos, Zsuzsa; Nagy, Mate; Vicsek, Tamas [Department of Biological Physics, Eoetvoes University, Pazmany Peter setany 1A, H-1117, Budapest (Hungary); Leven, Severin, E-mail: vicsek@hal.elte.h [Laboratory of Intelligent Systems, Ecole Polytechnique Federale de Lausanne (Switzerland)

    2010-12-15

    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.

  6. Bird migration through Middle Rio Grande riparian forests, 1994 to 1997

    Science.gov (United States)

    Michael D. Means; Deborah M. Finch

    1999-01-01

    Expanding human populations in the middle Rio Grande have increased demands on water, land, and other resources, potentially disrupting bird migration activities. From 1994 to 1997, a total of 26,350 birds of 157 species were banded and studied. Results include species composition, timing of migration, and habitat use. Recommendations for managers are included.

  7. The effects of urbanization on migrating birds on the western shore of Lake Michigan

    Science.gov (United States)

    Urbanization continues to transform the global landscape at an alarming rate, yet most ecological studies focus on more natural ecosystems. Many cities lie within major flyways for migrating birds, and our knowledge of how urbanization affects migrating birds is severely lacking....

  8. Can Nocturnal Flight Calls of the Migrating Songbird, American Redstart, Encode Sexual Dimorphism and Individual Identity?

    Directory of Open Access Journals (Sweden)

    Emily T Griffiths

    Full Text Available Bird species often use flight calls to engage in social behavior, for instance maintain group cohesion and to signal individual identity, kin or social associations, or breeding status of the caller. Additional uses also exist, in particular among migrating songbirds for communication during nocturnal migration. However, our understanding of the information that these vocalizations convey is incomplete, especially in nocturnal scenarios. To examine whether information about signaler traits could be encoded in flight calls we quantified several acoustic characteristics from calls of a nocturnally migrating songbird, the American Redstart. We recorded calls from temporarily captured wild specimens during mist-netting at the Powdermill Avian Research Center in Rector, PA. We measured call similarity among and within individuals, genders, and age groups. Calls from the same individual were significantly more similar to one another than to the calls of other individuals, and calls were significantly more similar among individuals of the same sex than between sexes. Flight calls from hatching-year and after hatching-year individuals were not significantly different. Our results suggest that American Redstart flight calls may carry identifiers of gender and individual identity. To our knowledge, this is the first evidence of individuality or sexual dimorphism in the flight calls of a migratory songbird. Furthermore, our results suggest that flight calls may have more explicit functions beyond simple group contact and cohesion. Nocturnal migration may require coordination among numerous individuals, and the use of flight calls to transmit information among intra- and conspecifics could be advantageous. Applying approaches that account for such individual and gender information may enable more advanced research using acoustic monitoring.

  9. Correlating Flight Behavior and Radar Measurements for Species Based Classification of Bird Radar Echoes for Wind Energy Site Assessment

    Science.gov (United States)

    Werth, S. P.; Frasier, S. J.

    2015-12-01

    Wind energy is one of the fastest-growing segments of the world energy market, offering a clean and abundant source of electricity. However, wind energy facilities can have detrimental effects on wildlife, especially birds and bats. Monitoring systems based on marine navigation radar are often used to quantify migration near potential wind sites, but the ability to reliably distinguish between bats and different varieties of birds has not been practically achieved. This classification capability would enable wind site selection that protects more vulnerable species, such as bats and raptors. Flight behavior, such as wing beat frequency, changes in speed, or changes in orientation, are known to vary by species [1]. The ability to extract these properties from radar data could ultimately enable a species based classification scheme. In this work, we analyze the relationship between radar measurements and bird flight behavior in echoes from avifauna. During the 2014 fall migration season, the UMass dual polarized weather radar was used to collect low elevation observations of migrating birds as they traversed through a fixed antenna beam. The radar was run during the night time, in clear-air conditions. Data was coherently integrated, and detections of biological targets exceeding an SNR threshold were extracted. Detections without some dominant frequency content (i.e. clear periodicity, potentially the wing beat frequency) were removed from the sample in order to isolate observations suspected to contain a single species or bird. For the remaining detections, measurements including the polarimetric products and the Doppler spectrum were extracted at each time step over the duration of the observation. The periodic and time changing nature of some of these different measurements was found to have a strong correlation with flight behavior (i.e. flapping vs. gliding behavior). Assumptions about flight behavior and orientation were corroborated through scattering

  10. 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.

  11. Historical diversification of migration patterns in a passerine bird.

    Science.gov (United States)

    Pérez-Tris, Javier; Bensch, Staffan; Carbonell, Roberto; Helbig, Andreas J; Tellería, José Luis

    2004-08-01

    Migratory strategies of birds require complex orientation mechanisms, morphological adaptations, and life-history adjustments. From an evolutionary perspective, it is important to know how fast this complex combination of traits can evolve. We analyzed mitochondrial control-region DNA sequences in 241 blackcaps (Sylvia atricapilla) from 12 populations with different migratory behaviors. The sample included sedentary populations in Europe and Atlantic archipelagos and migratory populations with different distances of migration, from regional to intercontinental migrations, and different heading directions (due to a migratory divide in central Europe). There was no genetic structure between migratory and sedentary populations, or among populations from different biogeographic areas (Atlantic islands, the Iberian Peninsula, or the continent), however we found evidence of a genetic structure when comparing populations located on either side of the migratory divide. These findings support an independent evolution of highly divergent migratory strategies in blackcaps, occurring after a postglacial colonization of the continent along western and eastern routes. Accordingly, mismatch-distribution analyses suggested an expansion of blackcaps from a very small population size, and time estimates dated such an expansion during the last postglacial period. However, the populations in Gibraltar, located in a putative Mediterranean refuge, appeared to be independent of these processes, showing evidence of restricted gene flow with other populations and demonstrating insignificant historical changes in effective population size. Our results show that the interruption of gene flow between migratory and sedentary populations is not necessary for the maintenance of such a polymorphism, and that even the most divergent migratory strategies of a bird species are susceptible to evolution in response to historical environmental changes.

  12. Heuristic Optimization Applied to an Intrinsically Difficult Problem: Birds Formation Flight

    DEFF Research Database (Denmark)

    Filippone, Antonino

    1996-01-01

    The birds formation flight is studied by means oftheoretical aerodynamics, heuristic methods anddistributed systems. A simplified aerodynamic analog is presented, and calculations of drag savings and flight range are shown for sometypical cases, including the line abreast flightwith various...

  13. Long flights do not influence immune responses of a long-distance migrant bird: a wind-tunnel experiment.

    Science.gov (United States)

    Hasselquist, Dennis; Lindström, Ake; Jenni-Eiermann, Susi; Koolhaas, Anita; Piersma, Theunis

    2007-04-01

    Heavy physical work can result in physiological stress and suppressed immune function. Accordingly, long-distance migrant birds that fly for thousands of km within days can be expected to show immunosuppression, and hence be more vulnerable to infections en route. The red knot Calidris canutus Linnaeus is a long-distance migrant shorebird. We flew red knots the equivalent of 1500 km over 6 days in a wind tunnel. The humoral and cell-mediated immune responses of the flyers were compared to those of non-flying controls. Humoral immunity was measured as antibody production against injected diphtheria and tetanus antigens, and cell-mediated response as phytohemagglutinin-induced wing-web swelling. Blood corticosterone levels, which may modulate immune function, were measured in parallel. The long flights had no detectable effects on humoral or cell-mediated immune responses, or on corticosterone levels. Thus, flight performance per se may not be particularly stressful or immunosuppressive in red knots. Some birds assigned as flyers refused to fly for extended periods. Before flights started, these non-flyers had significantly lower antibody responses against tetanus than the birds that carried out the full flight program. This suggests that only birds in good physical condition may be willing to take on heavy exercise. We conclude that these long-distance migrants appear well adapted to the work load induced by long flights, enabling them to cope with long flight distances without increased stress levels and suppression of immunity. Whether this also applies in the wild, where the migrating birds may face adverse weather and food conditions, remains to be investigated.

  14. 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.

  15. Extending bioacoustic monitoring of birds aloft through flight call localization with a three-dimensional microphone array.

    Science.gov (United States)

    Stepanian, Phillip M; Horton, Kyle G; Hille, David C; Wainwright, Charlotte E; Chilson, Phillip B; Kelly, Jeffrey F

    2016-10-01

    Bioacoustic localization of bird vocalizations provides unattended observations of the location of calling individuals in many field applications. While this technique has been successful in monitoring terrestrial distributions of calling birds, no published study has applied these methods to migrating birds in flight. The value of nocturnal flight call recordings can increase with the addition of three-dimensional position retrievals, which can be achieved with adjustments to existing localization techniques. Using the time difference of arrival method, we have developed a proof-of-concept acoustic microphone array that allows the three-dimensional positioning of calls within the airspace. Our array consists of six microphones, mounted in pairs at the top and bottom of three 10-m poles, arranged in an equilateral triangle with sides of 20 m. The microphone array was designed using readily available components and costs less than $2,000 USD to build and deploy. We validate this technique using a kite-lofted GPS and speaker package, and obtain 60.1% of vertical retrievals within the accuracy of the GPS measurements (±5 m) and 80.4% of vertical retrievals within ±10 m. The mean Euclidian distance between the acoustic retrievals of flight calls and the GPS truth was 9.6 m. Identification and localization of nocturnal flight calls have the potential to provide species-specific spatial characterizations of bird migration within the airspace. Even with the inexpensive equipment used in this trial, low-altitude applications such as surveillance around wind farms or oil platforms can benefit from the three-dimensional retrievals provided by this technique.

  16. 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 ...

  17. 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...

  18. Bird species migration ratio in East Asia, Australia, and surrounding islands.

    Science.gov (United States)

    Kuo, Yiliang; Lin, Da-Li; Chuang, Fu-Man; Lee, Pei-Fen; Ding, Tzung-Su

    2013-08-01

    Bird migration and its relationship with the contemporary environment have attracted long-term discussion. We calculated the avian migration ratio (the proportion of breeding species that migrate) in the areas from 70°E to 180°E and examined its relationship with the annual ranges of ambient temperature, primary productivity (estimated by the Enhanced Vegetation Index), and precipitation, along with island isolation and elevational range. The avian migration ratio increased with increasing latitude in general but varied greatly between the two hemispheres. Additionally, it showed minimal differences between continents and islands. Our analyses revealed that the seasonality of ambient temperature, which represents the energy expenditure of birds, is the dominant factor in determining bird species migration. Seasonality in primary productivity and other environmental factors play an indirect or limited role in bird species migration. The lower avian migration ratio in the Southern Hemisphere can be attributed to its paleogeographical isolation, stable paleoclimate, and warm contemporary environment. Under current trends of global warming, our findings should lead to further studies of the impact of warming on bird migration.

  19. Bird species migration ratio in East Asia, Australia, and surrounding islands

    Science.gov (United States)

    Kuo, Yiliang; Lin, Da-Li; Chuang, Fu-Man; Lee, Pei-Fen; Ding, Tzung-Su

    2013-08-01

    Bird migration and its relationship with the contemporary environment have attracted long-term discussion. We calculated the avian migration ratio (the proportion of breeding species that migrate) in the areas from 70°E to 180°E and examined its relationship with the annual ranges of ambient temperature, primary productivity (estimated by the Enhanced Vegetation Index), and precipitation, along with island isolation and elevational range. The avian migration ratio increased with increasing latitude in general but varied greatly between the two hemispheres. Additionally, it showed minimal differences between continents and islands. Our analyses revealed that the seasonality of ambient temperature, which represents the energy expenditure of birds, is the dominant factor in determining bird species migration. Seasonality in primary productivity and other environmental factors play an indirect or limited role in bird species migration. The lower avian migration ratio in the Southern Hemisphere can be attributed to its paleogeographical isolation, stable paleoclimate, and warm contemporary environment. Under current trends of global warming, our findings should lead to further studies of the impact of warming on bird migration.

  20. High Altitude Bird Migration at Temperate Latitudes: A Synoptic Perspective on Wind Assistance

    NARCIS (Netherlands)

    Dokter, A.M.; Shamoun-Baranes, J.; Kemp, M.U.; Tijm, S.; Holleman, I.

    2013-01-01

    At temperate latitudes the synoptic patterns of bird migration are strongly structured by the presence of cyclones and anticyclones, both in the horizontal and altitudinal dimensions. In certain synoptic conditions, birds may efficiently cross regions with opposing surface wind by choosing a higher

  1. 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

  2. Brain regions associated with visual cues are important for bird migration.

    Science.gov (United States)

    Vincze, Orsolya; Vágási, Csongor I; Pap, Péter L; Osváth, Gergely; Møller, Anders Pape

    2015-11-01

    Long-distance migratory birds have relatively smaller brains than short-distance migrants or residents. Here, we test whether reduction in brain size with migration distance can be generalized across the different brain regions suggested to play key roles in orientation during migration. Based on 152 bird species, belonging to 61 avian families from six continents, we show that the sizes of both the telencephalon and the whole brain decrease, and the relative size of the optic lobe increases, while cerebellum size does not change with increasing migration distance. Body mass, whole brain size, optic lobe size and wing aspect ratio together account for a remarkable 46% of interspecific variation in average migration distance across bird species. These results indicate that visual acuity might be a primary neural adaptation to the ecological challenge of migration. © 2015 The Author(s).

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

    OpenAIRE

    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 model, and to finally 3) predict bird strike risks for different spatial and temporal scales. A potential sensor to achieve these aims is the already existing European network of weather radars, bu...

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

    International Nuclear Information System (INIS)

    Spivey, Robin J.; Bishop, Charles M.

    2014-01-01

    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

  5. 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.

  6. 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

  7. MASS CHANGES IN MIGRATING BIRDS - THE EVIDENCE FOR FAT AND PROTEIN STORAGE REEXAMINED

    NARCIS (Netherlands)

    PIERSMA, T

    The fact that one cannot kill a bird twice makes it very difficult to determine the relative contributions of fat and non-fat components to increases in body mass before migratory flights in individual birds. Knowing the relative contributions of these components is of obvious energetic interest

  8. 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.

  9. Seasonally Changing Cryptochrome 1b Expression in the Retinal Ganglion Cells of a Migrating Passerine Bird.

    Directory of Open Access Journals (Sweden)

    Christine Nießner

    Full Text Available Cryptochromes, blue-light absorbing proteins involved in the circadian clock, have been proposed to be the receptor molecules of the avian magnetic compass. In birds, several cryptochromes occur: Cryptochrome 2, Cryptochrome 4 and two splice products of Cryptochrome 1, Cry1a and Cry1b. With an antibody not distinguishing between the two splice products, Cryptochrome 1 had been detected in the retinal ganglion cells of garden warblers during migration. A recent study located Cry1a in the outer segments of UV/V-cones in the retina of domestic chickens and European robins, another migratory species. Here we report the presence of cryptochrome 1b (eCry1b in retinal ganglion cells and displaced ganglion cells of European Robins, Erithacus rubecula. Immuno-histochemistry at the light microscopic and electron microscopic level showed eCry1b in the cell plasma, free in the cytosol as well as bound to membranes. This is supported by immuno-blotting. However, this applies only to robins in the migratory state. After the end of the migratory phase, the amount of eCry1b was markedly reduced and hardly detectable. In robins, the amount of eCry1b in the retinal ganglion cells varies with season: it appears to be strongly expressed only during the migratory period when the birds show nocturnal migratory restlessness. Since the avian magnetic compass does not seem to be restricted to the migratory phase, this seasonal variation makes a role of eCry1b in magnetoreception rather unlikely. Rather, it could be involved in physiological processes controlling migratory restlessness and thus enabling birds to perform their nocturnal flights.

  10. Differences in speed and duration of bird migration between spring and autumn

    NARCIS (Netherlands)

    Nilsson, Cecilia; Klaassen, Raymond H. G.; Alerstam, Thomas

    It has been suggested that birds migrate faster in spring than in autumn because of competition for arrival order at breeding grounds and environmental factors such as increased daylight. Investigating spring and autumn migration performances is important for understanding ecological and

  11. Improving the quantification of waterfowl migration with remote sensing and bird tracking

    NARCIS (Netherlands)

    Si, Y.; Xin, Q.; Prins, H.H.T.; Boer, de W.F.; Gong, P.

    2015-01-01

    Accurately quantifying waterfowl migration patterns is pertinent to monitor ecosystem health and control bird-borne infectious diseases. In this review, we summarize the current understanding of the environmental mechanisms that drive waterfowl migration and then investigate the effect of intra- and

  12. Impact of Spring Bird Migration on the Range Expansion of Ixodes scapularis Tick Population.

    Science.gov (United States)

    Wu, Xiaotian; Röst, Gergely; Zou, Xingfu

    2016-01-01

    Many observational studies suggest that seasonal migratory birds play an important role in spreading Ixodes scapularis, a vector of Lyme disease, along their migratory flyways, and they are believed to be responsible for geographic range expansion of I. scapularis in Canada. However, the interplay between the dynamics of I. scapularis on land and migratory birds in the air is not well understood. In this study, we develop a periodic delay meta-population model which takes into consideration the local landscape for tick reproduction within patches and the times needed for ticks to be transported by birds between patches. Assuming that the tick population is endemic in the source region, we find that bird migration may boost an already established tick population at the subsequent region and thus increase the risk to humans, or bird migration may help ticks to establish in a region where the local landscape is not appropriate for ticks to survive in the absence of bird migration, imposing risks to public health. This theoretical study reveals that bird migration plays an important role in the geographic range expansion of I. scapularis, and therefore our findings may suggest some strategies for Lyme disease prevention and control.

  13. Urban habitats and feeders both contribute to flight initiation distance reduction in birds

    OpenAIRE

    Anders Pape Møller; Piotr Tryjanowski; Mario Díaz; Zbigniew Kwieciński; Piotr Indykiewicz; Cezary Mitrus; Artur Goławski; Michał Polakowski

    2015-01-01

    Animals respond to approaching predators by taking flight at a distance that optimizes the costs and benefits of such flight. Previous studies have shown that urban populations of birds have shorter flight initiation distances than rural populations of the same species, that this difference is partly explained by differences in the community of predators, and that a longer history of urbanization implies a greater reduction in flight initiation distance in urban populations. The use of birdfe...

  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. Migrating songbirds on stopover prepare for, and recover from, oxidative challenges posed by long-distance flight.

    Science.gov (United States)

    Skrip, Megan M; Bauchinger, Ulf; Goymann, Wolfgang; Fusani, Leonida; Cardinale, Massimiliano; Alan, Rebecca R; McWilliams, Scott R

    2015-08-01

    Managing oxidative stress is an important physiological function for all aerobic organisms, particularly during periods of prolonged high metabolic activity, such as long-distance migration across ecological barriers. However, no previous study has investigated the oxidative status of birds at different stages of migration and whether that oxidative status depends on the condition of the birds. In this study, we compared (1) energy stores and circulating oxidative status measures in (a) two species of Neotropical migrants with differing migration strategies that were sampled at an autumn stopover site before an ecological barrier; and (b) a species of trans-Saharan migrant sampled at a spring stopover site after crossing an ecological barrier; and (2) circulating oxidative measures and indicators of fat metabolism in a trans-Saharan migrant after stopovers of varying duration (0-8 nights), based on recapture records. We found fat stores to be positively correlated with circulating antioxidant capacity in Blackpoll Warblers and Red-eyed Vireos preparing for fall migration on Block Island, USA, but uncorrelated in Garden Warblers on the island of Ponza, Italy, after a spring crossing of the Sahara Desert and Mediterranean Sea. In all circumstances, fat stores were positively correlated with circulating lipid oxidation levels. Among Garden Warblers on the island of Ponza, fat anabolism increased with stopover duration while oxidative damage levels decreased. Our study provides evidence that birds build antioxidant capacity as they build fat stores at stopover sites before long flights, but does not support the idea that antioxidant stores remain elevated in birds with high fuel levels after an ecological barrier. Our results further suggest that lipid oxidation may be an inescapable hazard of using fats as the primary fuel for flight. Yet, we also show that birds on stopover are capable of recovering from the oxidative damage they have accrued during migration, as

  17. 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

  18. Causes and consequences of partial migration in a passerine bird

    NARCIS (Netherlands)

    Hegemann, Arne; Marra, Peter P.; Tieleman, B. Irene

    2015-01-01

    Many animal species have populations in which some individuals migrate and others remain on the breeding grounds. This phenomenon is called partial migration. Despite substantial theoretical work, empirical data on causes and consequences of partial migration remain scarce, mainly because of

  19. 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...

  20. Differential catabolism of muscle protein in garden warblers (Sylvia borin): flight and leg muscle act as a protein source during long-distance migration.

    Science.gov (United States)

    Bauchinger, U; Biebach, H

    2001-05-01

    Samples of flight and leg muscle tissue were taken from migratory garden warblers at three different stages of migration: (1) pre-flight: when birds face an extended flight phase within the next few days, (2) post-flight: when they have just completed an extended flight phase, and (3) recovery: when they are at the end of a stop-over period following an extended flight phase. The changes in body mass are closely related to the changes in flight (Pflight. From pre- to post-flight, the flight and the leg muscle masses decrease by about 22%, but are restored to about 12% above the pre-flight masses during the recovery period. Biochemical analyses show that following flight a selective reduction occurred in the myofibrillar (contractile) component of the flight muscle (Pflight and leg muscle act as a protein source during long-distance migration. As a loss of leg muscle mass is additionally observed besides the loss in flight muscle mass, mass change seems not to be strictly associated with the mechanical power output requirements during flight. Whereas the specific content of sarcoplasmic proteins in the flight muscle is nearly twice as high as that in the leg muscle (Pflight muscle is one of the highest observed in muscles of a vertebrate.

  1. Modelling the progression of bird migration with conditional autoregressive models applied to ringing data.

    Science.gov (United States)

    Ambrosini, Roberto; Borgoni, Riccardo; Rubolini, Diego; Sicurella, Beatrice; Fiedler, Wolfgang; Bairlein, Franz; Baillie, Stephen R; Robinson, Robert A; Clark, Jacquie A; Spina, Fernando; Saino, Nicola

    2014-01-01

    Migration is a fundamental stage in the life history of several taxa, including birds, and is under strong selective pressure. At present, the only data that may allow for both an assessment of patterns of bird migration and for retrospective analyses of changes in migration timing are the databases of ring recoveries. We used ring recoveries of the Barn Swallow Hirundo rustica collected from 1908-2008 in Europe to model the calendar date at which a given proportion of birds is expected to have reached a given geographical area ('progression of migration') and to investigate the change in timing of migration over the same areas between three time periods (1908-1969, 1970-1990, 1991-2008). The analyses were conducted using binomial conditional autoregressive (CAR) mixed models. We first concentrated on data from the British Isles and then expanded the models to western Europe and north Africa. We produced maps of the progression of migration that disclosed local patterns of migration consistent with those obtained from the analyses of the movements of ringed individuals. Timing of migration estimated from our model is consistent with data on migration phenology of the Barn Swallow available in the literature, but in some cases it is later than that estimated by data collected at ringing stations, which, however, may not be representative of migration phenology over large geographical areas. The comparison of median migration date estimated over the same geographical area among time periods showed no significant advancement of spring migration over the whole of Europe, but a significant advancement of autumn migration in southern Europe. Our modelling approach can be generalized to any records of ringing date and locality of individuals including those which have not been recovered subsequently, as well as to geo-referenced databases of sightings of migratory individuals.

  2. Bird migration advances more strongly in urban environments.

    Science.gov (United States)

    Tryjanowski, Piotr; Sparks, Tim H; Kuźniak, Stanisław; Czechowski, Paweł; Jerzak, Leszek

    2013-01-01

    Urbanization has a marked effect on the reproduction and other ecological and behavioural traits of many living organisms, including birds. In migrant birds, survival and reproductive output is influenced by the (mis)synchronization of arrival with the availability of resources. Many recent studies have shown that arrival timing is related to temperatures en-route and at destination. Because urban areas are "heat islands", with higher temperatures that influence earlier vegetation and invertebrate development, this should favour earlier arrival of migrant birds to cities rather than to rural areas. In this paper, we analysed differences between urban and rural habitats in mean dates and trends of first arrival dates of 18 species of migratory bird species in western Poland during 1983-2010. For many individual species, and overall, mean first arrival date was significantly earlier in rural areas than in urban areas (significant for 11 species). However, the trend towards earlier first arrival dates was stronger in urban areas for 15 of the 18 species (significantly stronger in four species). Consequently, arrival dates in urban areas are fast approaching, or have now matched or passed those in rural areas. These findings suggest that recent environmental changes may have more rapidly changed the migratory habits of birds occupying urban habitats than those occupying rural habitats.

  3. Bird migration advances more strongly in urban environments.

    Directory of Open Access Journals (Sweden)

    Piotr Tryjanowski

    Full Text Available Urbanization has a marked effect on the reproduction and other ecological and behavioural traits of many living organisms, including birds. In migrant birds, survival and reproductive output is influenced by the (missynchronization of arrival with the availability of resources. Many recent studies have shown that arrival timing is related to temperatures en-route and at destination. Because urban areas are "heat islands", with higher temperatures that influence earlier vegetation and invertebrate development, this should favour earlier arrival of migrant birds to cities rather than to rural areas. In this paper, we analysed differences between urban and rural habitats in mean dates and trends of first arrival dates of 18 species of migratory bird species in western Poland during 1983-2010. For many individual species, and overall, mean first arrival date was significantly earlier in rural areas than in urban areas (significant for 11 species. However, the trend towards earlier first arrival dates was stronger in urban areas for 15 of the 18 species (significantly stronger in four species. Consequently, arrival dates in urban areas are fast approaching, or have now matched or passed those in rural areas. These findings suggest that recent environmental changes may have more rapidly changed the migratory habits of birds occupying urban habitats than those occupying rural habitats.

  4. 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.

  5. Nematode parasite diversity in birds: the role of host ecology, life history and migration.

    Science.gov (United States)

    Leung, Tommy L F; Koprivnikar, Janet

    2016-11-01

    Previous studies have found that migratory birds generally have a more diverse array of pathogens such as parasites, as well as higher intensities of infection. However, it is not clear whether this is driven by the metabolic and physiological demands of migration, differential selection on host life-history traits or basic ecological differences between migratory and non-migratory species. Parasitic helminths can cause significant pathology in their hosts, and many are trophically transmitted such that host diet and habitat use play key roles in the acquisition of infections. Given the concurrent changes in avian habitats and migratory behaviour, it is critical to understand the degree to which host ecology influences their parasite communities. We examined nematode parasite diversity in 153 species of Anseriformes (water birds) and Accipitriformes (predatory birds) in relation to their migratory behaviour, diet, habitat use, geographic distribution and life history using previously published data. Overall, migrators, host species with wide geographic distributions and those utilizing multiple aquatic habitats had greater nematode richness (number of species), and birds with large clutches harboured more diverse nematode fauna with respect to number of superfamilies. Separate analyses for each host order found similar results related to distribution, habitat use and migration; however, herbivorous water birds played host to a less diverse nematode community compared to those that consume some animals. Birds using multiple aquatic habitats have a more diverse nematode fauna relative to primarily terrestrial species, likely because there is greater opportunity for contact with parasite infectious stages and/or consumption of infected hosts. As such, omnivorous and carnivorous birds using aquatic habitats may be more affected by environmental changes that alter their diet and range. Even though there were no overall differences in their ecology and life history

  6. The migration and conservation of birds in a Southern African context

    Directory of Open Access Journals (Sweden)

    H. Bouwman

    1997-07-01

    Full Text Available The migration of birds is a phenomenon that has been studied for more than two thousand years. Almost half of the extant bird species undertake migration, covering distances of a few tens of kilometres, up to a calculated 50 000 km per year, sometimes at heights exceeding 9 000 m, at very low temperatures, during the day or night. Some species fly actively and continuously for more than a 100 hours, whilst making efficient use of energy. A variety of strategies and physiological mechanisms are used to perform such feats, but many remain to be studied.

  7. 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

  8. Bird migration and risk for H5N1 transmission into Qinghai Lake, China.

    Science.gov (United States)

    Cui, Peng; Hou, Yuansheng; Xing, Zhi; He, Yubang; Li, Tianxian; Guo, Shan; Luo, Ze; Yan, Baoping; Yin, Zuohua; Lei, Fumin

    2011-05-01

    The highly pathogenic avian influenza H5N1 virus still cause devastating effects to humans, agricultural poultry flocks, and wild birds. Wild birds are also detected to carry H5N1 over long distances and are able to introduce it into new areas during migration. In this article, our objective is to provide lists of bird species potentially involved in the introduction of highly pathogenic avian influenza H5N1 in Qinghai Lake, which is an important breeding and stopover site for aquatic birds along the Central Asian Flyway. Bird species were classified according to the following behavioral and ecological factors: migratory status, abundance, degree of mixing species and gregariousness, and the prevalence rate of H5N1 virus. Most of the high-risk species were from the family Anatidae, order Anseriformes (9/14 in spring, 11/15 in fall). We also estimated the relative risk of bird species involved by using a semi-quantitative method; species from family Anatidae accounted for over 39% and over 91% of the total risk at spring and fall migration periods, respectively. Results also show the relative risk for each bird aggregating site in helping to identify high-risk areas. This work may also be instructive and meaningful to the avian influenza surveillance in the breeding, stopover, and wintering sites besides Qinghai Lake along the Central Asian Flyway.

  9. Bird mortality during nocturnal migration over Lake Michigan: A case study

    Science.gov (United States)

    Diehl, Robert H.; Bates, John M.; Willard, David E.; Gnoske, Thomas P.

    2014-01-01

    Millions of birds die each year during migration. Most of this mortality goes unobserved and conditions surrounding the actual events are often not thoroughly documented. We present a case study of substantial migrant casualties along the shores of southwestern Lake Michigan during May 1996 when we found 2,981 dead birds of 114 species, mostly migrant passerines. An unusual sequence of events allowed us to document the circumstances surrounding this migratory bird kill. Bird carcasses appeared on the southwestern shores of Lake Michigan in the days following storm systems that produced high rain and in one case, hail. Encounters between birds and precipitation over open water were recorded by weather radar, and were followed by winds that drifted dead birds toward highly populated shorelines where the kill was observed and documented. Climatologically, May 1996 was exceptional for producing weather conditions that both killed birds en masse and allowed the mortality to be documented. As a result, this is one of the more thoroughly documented instances of a weather-related mass mortality event during migration.

  10. Space-based Remote Sensing: A Tool for Studying Bird Migration Across Multiple Scales

    Science.gov (United States)

    Smith, James A.

    2005-01-01

    The study of bird migration on a global scale is one of the compelling and challenging problems of modern biology with major implications for human health and conservation biology. Migration and conservation efforts cross national boundaries and are subject to numerous international agreements and treaties. Space based technology offers new opportunities to shed understanding on the distribution and migration of organisms on the planet and their sensitivity to human disturbances and environmental changes. Our working hypothesis is that individual organism biophysical models of energy and water balance, driven by satellite measurements of spatio-temporal gradients in climate and habitat, will help us to explain the variability in avian species richness and distribution. Further, these models provide an ecological forecasting tool for science and application users to visualize the possible consequences of loss of wetlands, flooding, or other natural disasters such as hurricanes on avian biodiversity and bird migration.

  11. Comparison of Visually Guided Flight in Insects and Birds

    OpenAIRE

    Douglas L. Altshuler; Mandyam V. Srinivasan; Mandyam V. Srinivasan

    2018-01-01

    Over the last half century, work with flies, bees, and moths have revealed a number of visual guidance strategies for controlling different aspects of flight. Some algorithms, such as the use of pattern velocity in forward flight, are employed by all insects studied so far, and are used to control multiple flight tasks such as regulation of speed, measurement of distance, and positioning through narrow passages. Although much attention has been devoted to long-range navigation and homing in b...

  12. Flight distance and population trends in European breeding birds

    OpenAIRE

    Anders Pape Møller

    2008-01-01

    Flight distance reflects the risk that individual animals are willing to take when approached by a potential predator, as shown by a negative relationship between susceptibility to predation and flight distance. Species with long flight distances should more often suffer from disruption of their activities by potential predators, including humans, than species with short distances, resulting in declining reproductive success and hence declining population size of such species if disturbance h...

  13. Animal tracking meets migration genomics: transcriptomic analysis of a partially migratory bird species.

    Science.gov (United States)

    Franchini, Paolo; Irisarri, Iker; Fudickar, Adam; Schmidt, Andreas; Meyer, Axel; Wikelski, Martin; Partecke, Jesko

    2017-06-01

    Seasonal migration is a widespread phenomenon, which is found in many different lineages of animals. This spectacular behaviour allows animals to avoid seasonally adverse environmental conditions to exploit more favourable habitats. Migration has been intensively studied in birds, which display astonishing variation in migration strategies, thus providing a powerful system for studying the ecological and evolutionary processes that shape migratory behaviour. Despite intensive research, the genetic basis of migration remains largely unknown. Here, we used state-of-the-art radio-tracking technology to characterize the migratory behaviour of a partially migratory population of European blackbirds (Turdus merula) in southern Germany. We compared gene expression of resident and migrant individuals using high-throughput transcriptomics in blood samples. Analyses of sequence variation revealed a nonsignificant genetic structure between blackbirds differing by their migratory phenotype. We detected only four differentially expressed genes between migrants and residents, which might be associated with hyperphagia, moulting and enhanced DNA replication and transcription. The most pronounced changes in gene expression occurred between migratory birds depending on when, in relation to their date of departure, blood was collected. Overall, the differentially expressed genes detected in this analysis may play crucial roles in determining the decision to migrate, or in controlling the physiological processes required for the onset of migration. These results provide new insights into, and testable hypotheses for, the molecular mechanisms controlling the migratory phenotype and its underlying physiological mechanisms in blackbirds and other migratory bird species. © 2017 John Wiley & Sons Ltd.

  14. American exceptionalism: population trends and flight initiation distances in birds from three continents.

    Directory of Open Access Journals (Sweden)

    Anders Pape Møller

    Full Text Available 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.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.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.

  15. 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

    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. 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. 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.

  16. 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.

  17. 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.

  18. 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

  19. Polymorphism at the Clock gene predicts phenology of long-distance migration in birds.

    Science.gov (United States)

    Saino, Nicola; Bazzi, Gaia; Gatti, Emanuele; Caprioli, Manuela; Cecere, Jacopo G; Possenti, Cristina D; Galimberti, Andrea; Orioli, Valerio; Bani, Luciano; Rubolini, Diego; Gianfranceschi, Luca; Spina, Fernando

    2015-04-01

    Dissecting phenotypic variance in life history traits into its genetic and environmental components is at the focus of evolutionary studies and of pivotal importance to identify the mechanisms and predict the consequences of human-driven environmental change. The timing of recurrent life history events (phenology) is under strong selection, but the study of the genes that control potential environmental canalization in phenological traits is at its infancy. Candidate genes for circadian behaviour entrained by photoperiod have been screened as potential controllers of phenological variation of breeding and moult in birds, with inconsistent results. Despite photoperiodic control of migration is well established, no study has reported on migration phenology in relation to polymorphism at candidate genes in birds. We analysed variation in spring migration dates within four trans-Saharan migratory species (Luscinia megarhynchos; Ficedula hypoleuca; Anthus trivialis; Saxicola rubetra) at a Mediterranean island in relation to Clock and Adcyap1 polymorphism. Individuals with larger number of glutamine residues in the poly-Q region of Clock gene migrated significantly later in one or, respectively, two species depending on sex and whether the within-individual mean length or the length of the longer Clock allele was considered. The results hinted at dominance of the longer Clock allele. No significant evidence for migration date to covary with Adcyap1 polymorphism emerged. This is the first evidence that migration phenology is associated with Clock in birds. This finding is important for evolutionary studies of migration and sheds light on the mechanisms that drive bird phenological changes and population trends in response to climate change. © 2015 John Wiley & Sons Ltd.

  20. A robust tool highlights the influence of bird migration on influenza A virus evolution.

    Science.gov (United States)

    Dugan, Vivien G

    2012-12-01

    One of the fundamental unknowns in the field of influenza biology is a panoramic understanding of the role wild birds play in the global maintenance and spread of influenza A viruses. Wild aquatic birds are considered a reservoir host for all lowly pathogenic avian influenza A viruses (AIV) and thus serve as a potential source of zoonotic AIV, such as Australasian-origin H5N1 responsible for morbidity and mortality in both poultry and humans, as well as genes that may contribute to the emergence of pandemic viruses. Years of broad, in-depth wild bird AIV surveillance have helped to decipher key observations and ideas regarding AIV evolution and viral ecology including the trending of viral lineages, patterns of gene flow within and between migratory flyways and the role of geographic boundaries in shaping viral evolution (Bahl et al. 2009; Lam et al. 2012). While these generally 'virus-centric' studies have ultimately advanced our broader understanding of AIV dynamics, recent studies have been more host-focused, directed at determining the potential impact of host behaviour on AIV, specifically, the influence of bird migration upon AIV maintenance and transmission. A large number of surveillance studies have taken place in Alaska, United States-a region where several global flyways overlap-with the aim of detecting the introduction of novel, Australasian-origin highly pathogenic H5N1 AIV into North America. By targeting bird species with known migration habits, long-distance migrators were determined to be involved in the intercontinental movement of individual AIV gene segments, but not entire viruses, between the Australasian and North American flyways (Koehler et al. 2008; Pearce et al. 2010). Yet, bird movement is not solely limited to long-distance migration, and the relationship of resident or nonmigratory and intermediate-distance migrant populations with AIV ecology has only recently been explored by Hill et al. (2012) in this issue of Molecular Ecology

  1. Transport of Babesia venatorum-infected Ixodes ricinus to Norway by northward migrating passerine birds

    Directory of Open Access Journals (Sweden)

    Røed Knut H

    2011-06-01

    Full Text Available Abstract Background Bovine babesiosis is regarded as a limited health problem for Norwegian cows, and the incidence has decreased markedly since the 1930s. Rare cases of babesiosis in splenectomised humans from infection with Babesia divergens and B.venatorum have been described. The objective of this study was to determine whether birds can introduce Babesia-infected ticks. There are between 30 and 85 million passerine birds that migrate to Norway every spring. Methods Passerine birds were examined for ticks at four bird observatories along the southern Norwegian coast during the spring migrations of 2003, 2004 and 2005. The presence of Babesia was detected in the nymphs of Ixodes ricinus by real-time PCR. Positive samples were confirmed using PCR, cloning and phylogenetic analyses. Results Of 512 ticks examined, real-time PCR revealed five to be positive (1.0%. Of these, four generated products that indicated the presence of Babesia spp.; each of these were confirmed to be from Babesia venatorum (EU1. Two of the four B. venatorum-positive ticks were caught from birds having an eastern migratory route (P Conclusions Birds transport millions of ticks across the North Sea, the Skagerrak and the Kattegat every year. Thus, even with the low prevalence of Babesia-infected ticks, a substantial number of infected ticks will be transported into Norway each year. Therefore, there is a continuous risk for introduction of new Babesia spp. into areas where I. ricinus can survive.

  2. Aeroelastic flutter of feathers, flight and the evolution of non-vocal communication in birds.

    Science.gov (United States)

    Clark, Christopher J; Prum, Richard O

    2015-11-01

    Tonal, non-vocal sounds are widespread in both ordinary bird flight and communication displays. We hypothesized these sounds are attributable to an aerodynamic mechanism intrinsic to flight feathers: aeroelastic flutter. Individual wing and tail feathers from 35 taxa (from 13 families) that produce tonal flight sounds were tested in a wind tunnel. In the wind tunnel, all of these feathers could flutter and generate tonal sound, suggesting that the capacity to flutter is intrinsic to flight feathers. This result implies that the aerodynamic mechanism of aeroelastic flutter is potentially widespread in flight of birds. However, the sounds these feathers produced in the wind tunnel replicated the actual flight sounds of only 15 of the 35 taxa. Of the 20 negative results, we hypothesize that 10 are false negatives, as the acoustic form of the flight sound suggests flutter is a likely acoustic mechanism. For the 10 other taxa, we propose our negative wind tunnel results are correct, and these species do not make sounds via flutter. These sounds appear to constitute one or more mechanism(s) we call 'wing whirring', the physical acoustics of which remain unknown. Our results document that the production of non-vocal communication sounds by aeroelastic flutter of flight feathers is widespread in birds. Across all birds, most evolutionary origins of wing- and tail-generated communication sounds are attributable to three mechanisms: flutter, percussion and wing whirring. Other mechanisms of sound production, such as turbulence-induced whooshes, have evolved into communication sounds only rarely, despite their intrinsic ubiquity in ordinary flight. © 2015. Published by The Company of Biologists Ltd.

  3. Possible linkage between neuronal recruitment and flight distance in migratory birds.

    Science.gov (United States)

    Barkan, Shay; Roll, Uri; Yom-Tov, Yoram; Wassenaar, Leonard I; Barnea, Anat

    2016-02-24

    New neuronal recruitment in an adult animal's brain is presumed to contribute to brain plasticity and increase the animal's ability to contend with new and changing environments. During long-distance migration, birds migrating greater distances are exposed to more diverse spatial information. Thus, we hypothesized that greater migration distance in birds would correlate with the recruitment of new neurons into the brain regions involved with migratory navigation. We tested this hypothesis on two Palearctic migrants - reed warblers (Acrocephalus scirpaceus) and turtle doves (Streptopelia turtur), caught in Israel while returning from Africa in spring and summer. Birds were injected with a neuronal birth marker and later inspected for new neurons in brain regions known to play a role in navigation - the hippocampus and nidopallium caudolateral. We calculated the migration distance of each individual by matching feather isotopic values (δ(2)H and δ(13)C) to winter base-maps of these isotopes in Africa. Our findings suggest a positive correlation between migration distance and new neuronal recruitment in two brain regions - the hippocampus in reed warblers and nidopallium caudolateral in turtle doves. This multidisciplinary approach provides new insights into the ability of the avian brain to adapt to different migration challenges.

  4. Modeling Bird Migration in Changing Habitats: Space-based Ornithology using Satellites and GIS

    Science.gov (United States)

    Smith, James A.; Deppe, Jill L.

    2008-01-01

    Understanding bird migration and avian biodiversity is one of the most compelling and challenging problems of modern biology with major implications for human health and conservation biology. Migration and conservation efforts cross national boundaries and are subject to numerous international agreements and treaties presenting challenges in both geographic space and time. Space based technology, coupled with geographic information systems, yields new opportunities to shed light on the distribution and movement of organisms on the planet and their sensitivity to human disturbances and environmental changes. At NASA, we are creating ecological forecasting tools for science and application users to address the consequences of loss of wetlands, flooding, drought or other natural disasters such as hurricanes on avian biodiversity and bird migration. In our work, we use individual organism biophysical models and drive these models with satellite observations and numerical weather predictions of the spatio-temporal gradients in climate and habitat. Geographic information system technology comprises one component of our overall simulation framework, especially for characterizing the changing habitats and conditions encountered by en-route migratory birds. Simulation provides a tool for studying bird migration across multiple scales and can be linked to mechanistic processes describing the time and energy budget states of migrating birds. Such models yield an understanding of how a migratory flyway and its component habitats function as a whole and link stop-over ecology with biological conservation and management. We present examples of our simulation of shorebirds, principally, pectoral sandpipers, along the central flyways of the United States and Canada from the Gulf of Mexico to Alaska.

  5. Monitoring bird migration in the Caribbean basin: multi-national cooperation can close the loop

    Science.gov (United States)

    Paul B. Hamel; Cecilia M. Riley; W. C. Hunter; Mark S. Woodrey

    2005-01-01

    The Gulf Coast Bird Observatory (GCBO) and the Southeastern Working Group of Partners in Flight have developed a protocol to monitor landbirds with volunteer observers performing avian censuses in the field. Field observations are compiled within a powerful internet database, and recording and summary capability is maintained by the GCBO. More than 100 observers have...

  6. 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

  7. Variation in energy intake and basal metabolic rate of a bird migrating in a wind tunnel

    NARCIS (Netherlands)

    Lindström, Å.; Klaassen, M.R.J.; Kvist, A.

    1999-01-01

    1. We studied the changes in body mass, metabolizable energy intake rate (ME) and basal metabolic rate (BMR) of a Thrush Nightingale, Luscinia luscinia, following repeated 12-h migratory flights in a wind tunnel. In total the bird flew for 176 h corresponding to 6300 km. This is the first study

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

    Science.gov (United States)

    Si, Yali; Skidmore, Andrew K; Wang, Tiejun; de Boer, Willem F; Debba, Pravesh; Toxopeus, Albert G; Li, Lin; Prins, Herbert H T

    2009-11-01

    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.

  9. 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.

  10. 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].

  11. 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

  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. 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)

  14. 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.

  15. Changes in bird-migration patterns associated with human-induced mortality.

    Science.gov (United States)

    Palacín, Carlos; Alonso, Juan C; Martín, Carlos A; Alonso, Javier A

    2017-02-01

    Many bird populations have recently changed their migratory behavior in response to alterations of the environment. We collected data over 16 years on male Great Bustards (Otis tarda), a species showing a partial migratory pattern (sedentary and migratory birds coexisting in the same breeding groups). We conducted population counts and radio tracked 180 individuals to examine differences in survival rates between migratory and sedentary individuals and evaluate possible effects of these differences on the migratory pattern of the population. Overall, 65% of individuals migrated and 35% did not. The average distance between breeding and postbreeding areas of migrant individuals was 89.9 km, and the longest average movement of sedentary males was 3.8 km. Breeding group and migration distance had no effect on survival. However, mortality of migrants was 2.4 to 3.5 times higher than mortality of sedentary birds. For marked males, collision with power lines was the main cause of death from unnatural causes (37.6% of all deaths), and migratory birds died in collisions with power lines more frequently than sedentary birds (21.3% vs 6.3%). The percentage of sedentary individuals increased from 17% in 1997 to 45% in 2012. These results were consistent with data collected from radio-tracked individuals: The proportion of migratory individuals decreased from 86% in 1997-1999 to 44% in 2006-2010. The observed decrease in the migratory tendency was not related to climatic changes (temperatures did not change over the study period) or improvements in habitat quality (dry cereal farmland area decreased in the main study area). Our findings suggest that human-induced mortality during migration may be an important factor shaping the migration patterns of species inhabiting humanized landscapes. © 2016 Society for Conservation Biology.

  16. Flight aerodynamics in enantiornithines: Information from a new Chinese Early Cretaceous bird.

    Science.gov (United States)

    Liu, Di; Chiappe, Luis M; Serrano, Francisco; Habib, Michael; Zhang, Yuguang; Meng, Qinjing

    2017-01-01

    We describe an exquisitely preserved new avian fossil (BMNHC-PH-919) from the Lower Cretaceous Yixian Formation of eastern Inner Mongolia, China. Although morphologically similar to Cathayornithidae and other small-sized enantiornithines from China's Jehol Biota, many morphological features indicate that it represents a new species, here named Junornis houi. The new fossil displays most of its plumage including a pair of elongated, rachis-dominated tail feathers similarly present in a variety of other enantiornithines. BMNHC-PH-919 represents the first record of a Jehol enantiornithine from Inner Mongolia, thus extending the known distribution of these birds into the eastern portion of this region. Furthermore, its well-preserved skeleton and wing outline provide insight into the aerodynamic performance of enantiornithines, suggesting that these birds had evolved bounding flight-a flight mode common to passeriforms and other small living birds-as early as 125 million years ago.

  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 (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.

  18. Effects of vehicle speed on flight initiation by Turkey vultures: implications for bird-vehicle collisions.

    Directory of Open Access Journals (Sweden)

    Travis L DeVault

    Full Text Available 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.

  19. 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

  20. 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.

  1. An assessment of spatio-temporal relationships between nocturnal bird migration traffic rates and diurnal bird stopover density.

    Science.gov (United States)

    Horton, Kyle G; Shriver, W Gregory; Buler, Jeffrey J

    2016-01-01

    Daily magnitudes and fluxes of landbird migration are often measured via nocturnal traffic rates aloft or diurnal densities within terrestrial habitats during stopover. However, these measures are not consistently correlated and at times reveal opposing trends. For this reason we sought to determine how comparison methods (daily magnitude or daily flux), nocturnal monitoring tools (weather surveillance radar, WSR; thermal imaging, TI), and temporal scale (preceding or following diurnal sampling) influenced correlation strength from stopover densities estimated by daily transect counts. We quantified nocturnal traffic rates at two temporal scales; averaged across the entire night and within individual decile periods of the night, and at two spatial scales; within 1 km of airspace surrounding the site via WSR and directly overhead within the narrow beam of a TI. Overall, the magnitude of daily bird density during stopover was positively related to the magnitude of broad-scale radar traffic rates of migrants on preceding and following nights during both the spring and fall. These relationships were strongest on the following night, and particularly from measures early in the night. Only during the spring on the following nights did we find positive correlations between the daily flux of transect counts and migration traffic rates (both WSR and TI). This indicates that our site likely had a more consistent daily turnover of migrants compared to the fall. The lack of general correlations between seasonal trends or daily flux in fine-scale TI traffic rates and stopover densities across or within nights was unexpected and likely due to poor sampling of traffic rates due to the camera's narrow beam. The order (preceding or following day) and metric of comparisons (magnitude or flux), as well as the tool (WSR or TI) used for monitoring nocturnal migration traffic can have dramatic impacts when compared with ground-based estimates of migrant density. WSR provided measures

  2. Comparison of wing morphology in three birds of prey: correlations with differences in flight behavior.

    Science.gov (United States)

    Corvidae, Elaine L; Bierregaard, Richard O; Peters, Susan E

    2006-05-01

    Flight is the overriding characteristic of birds that has influenced most of their morphological, physiological, and behavioral features. Flight adaptations are essential for survival in the wide variety of environments that birds occupy. Therefore, locomotor structure, including skeletal and muscular characteristics, is adapted to reflect the flight style necessitated by different ecological niches. Red-tailed hawks (Buteo jamaicensis) soar to locate their prey, Cooper's hawks (Accipiter cooperii) actively chase down avian prey, and ospreys (Pandion haliaetus) soar and hover to locate fish. In this study, wing ratios, proportions of skeletal elements, and relative sizes of selected flight muscles were compared among these species. Oxidative and glycolytic enzyme activities of several muscles were also analyzed via assays for citrate synthase (CS) and for lactate dehydrogenase (LDH). It was found that structural characteristics of these three raptors differ in ways consistent with prevailing aerodynamic models. The similarity of enzymatic activities among different muscles of the three species shows low physiological differentiation and suggests that wing architecture may play a greater role in determining flight styles for these birds. Copyright 2006 Wiley-Liss, Inc.

  3. Bird Flight as a Model for a Course in Unsteady Aerodynamics

    Science.gov (United States)

    Jacob, Jamey; Mitchell, Jonathan; Puopolo, Michael

    2014-11-01

    Traditional unsteady aerodynamics courses at the graduate level focus on theoretical formulations of oscillating airfoil behavior. Aerodynamics students with a vision for understanding bird-flight and small unmanned aircraft dynamics desire to move beyond traditional flow models towards new and creative ways of appreciating the motion of agile flight systems. High-speed videos are used to record kinematics of bird flight, particularly barred owls and red-shouldered hawks during perching maneuvers, and compared with model aircraft performing similar maneuvers. Development of a perching glider and associated control laws to model the dynamics are used as a class project. Observations are used to determine what different species and sizes of birds share in their methods to approach a perch under similar conditions. Using fundamental flight dynamics, simplified models capable of predicting position, attitude, and velocity of the flier are developed and compared with the observations. By comparing the measured data from the videos and predicted and measured motions from the glider models, it is hoped that the students gain a better understanding of the complexity of unsteady aerodynamics and aeronautics and an appreciation for the beauty of avian flight.

  4. Migratory connectivity and population-specific migration routes in a long-distance migratory bird.

    Science.gov (United States)

    Trierweiler, Christiane; Klaassen, Raymond H G; Drent, Rudi H; Exo, Klaus-Michael; Komdeur, Jan; Bairlein, Franz; Koks, Ben J

    2014-03-07

    Knowledge about migratory connectivity, the degree to which individuals from the same breeding site migrate to the same wintering site, is essential to understand processes affecting populations of migrants throughout the annual cycle. Here, we study the migration system of a long-distance migratory bird, the Montagu's harrier Circus pygargus, by tracking individuals from different breeding populations throughout northern Europe. We identified three main migration routes towards wintering areas in sub-Saharan Africa. Wintering areas and migration routes of different breeding populations overlapped, a pattern best described by 'weak (diffuse) connectivity'. Migratory performance, i.e. timing, duration, distance and speed of migration, was surprisingly similar for the three routes despite differences in habitat characteristics. This study provides, to our knowledge, a first comprehensive overview of the migration system of a Palaearctic-African long-distance migrant. We emphasize the importance of spatial scale (e.g. distances between breeding populations) in defining patterns of connectivity and suggest that knowledge about fundamental aspects determining distribution patterns, such as the among-individual variation in mean migration directions, is required to ultimately understand migratory connectivity. Furthermore, we stress that for conservation purposes it is pivotal to consider wintering areas as well as migration routes and in particular stopover sites.

  5. Repeatability of individual migration routes, wintering sites, and timing in a long-distance migrant bird.

    Science.gov (United States)

    van Wijk, Rien E; Bauer, Silke; Schaub, Michael

    2016-12-01

    Migratory birds are often faithful to wintering (nonbreeding) sites, and also migration timing is usually remarkably consistent, that is, highly repeatable. Spatiotemporal repeatability can be of advantage for multiple reasons, including familiarity with local resources and predators as well as avoiding the costs of finding a new place, for example, nesting grounds. However, when the environment is variable in space and time, variable site selection and timing might be more rewarding. To date, studies on spatial and temporal repeatability in short-lived long-distance migrants are scarce, most notably of first-time and subsequent migrations. Here, we investigated repeatability in autumn migration directions, wintering sites, and annual migration timing in Hoopoes ( Upupa epops ), a long-distance migrant, using repeated tracks of adult and first-time migrants. Even though autumn migration directions were mostly the same, individual wintering sites often changed from year to year with distances between wintering sites exceeding 1,000 km. The timing of migration was repeatable within an individual during autumn, but not during spring migration. We suggest that Hoopoes respond to variable environmental conditions such as north-south shifts in rainfall during winter and differing onset of the food availability during spring migration.

  6. 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

    Evidence for climate-driven phenological changes is rapidly increasing at all trophic levels. Our current poor knowledge of the detailed control of bird migration from the level of genes and hormonal control to direct physiological and behavioral responses hampers our ability to understand......-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...

  7. Quantifying the Risk of Introduction of West Nile Virus into Great Britain by Migrating Passerine Birds.

    Science.gov (United States)

    Bessell, P R; Robinson, R A; Golding, N; Searle, K R; Handel, I G; Boden, L A; Purse, B V; Bronsvoort, B M de C

    2016-10-01

    West Nile virus (WNV) is a mosquito borne arbovirus that circulates within avian reservoirs. WNV can spill over into humans and Equidae that are dead-end hosts for WNV but suffer fever, acute morbidity and sometimes death. Outbreaks of WNV are common across Africa and Eastern Europe, and there have also been sporadic outbreaks in Spain and the Camargue Regional Park in France, but never in Great Britain (GB). These areas all fall along a major bird migration route. In this study, we analyse a scenario in which WNV is circulating in the Camargue or in other wetland areas in France and we estimate the risk of northward migrating passerine birds stopping in a WNV hotspot, becoming infected and carrying active infection to GB. If the disease were circulating in the Camargue during a single migratory season, the probability that one or more migrating birds becomes infected and lands in GB whilst still infected is 0.881 with 0.384 birds arriving in areas of suitable vector habitat. However, if WNV became established in the Grand Brière National Park or La Brenne Regional Park wetland areas further to the north, the model predicts that at least one infected bird will continue to GB. Thus, GB is at risk of WNV introduction from the Camargue, but the risk is considerably greater if WNV were to circulate further north than its previous focus in France, but this is highly sensitive to the force of infection in the infected area. However, the risk of establishment and infection of humans in GB is dependent upon a number of additional factors, in particular the vector and epidemiological situation in GB. © 2014 The Authors. Transboundary and Emerging Diseases Published by Blackwell Verlag GmbH.

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

    Science.gov (United States)

    Bahl, Justin; Krauss, Scott; Kühnert, Denise; Fourment, Mathieu; Raven, Garnet; Pryor, S Paul; Niles, Lawrence J; Danner, Angela; Walker, David; Mendenhall, Ian H; Su, Yvonne C F; Dugan, Vivien G; Halpin, Rebecca A; Stockwell, Timothy B; Webby, Richard J; Wentworth, David E; Drummond, Alexei J; Smith, Gavin J D; Webster, Robert G

    2013-01-01

    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.

  9. 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.

  10. Shifts in Bird Migration Timing in North American Long-Distance and Short-Distance Migrants Are Associated with Climate Change

    OpenAIRE

    Zaifman, Jay; Shan, Daoyang; Ay, Ahmet; Jimenez, Ana Gabriela

    2017-01-01

    Bird migration is a synchronized event that has evolved over thousands of years. Changing temperatures due to climate change threaten the intricacies of migration timing for birds; however, the extent of these changes has only recently begun to be addressed. Utilizing data from the citizen-science website eBird and historical temperature data, we analyzed bird migration timing in two states warming quickly (Alaska and Maine) and one warming gradually (South Carolina). Using linear regressions...

  11. An integrated approach on free flight mechanisms in insects and birds.

    Science.gov (United States)

    Liu, Hao

    2005-11-01

    To provide an overall understanding of aerodynamic and dynamic mechanisms in flying insects and birds we have succeed in establishing a biology-inspired dynamic flight simulator, which is capable to mimic hovering, forward flight and quick-turn on a basis of modeling of realistic geometry and wing kinematics, and modeling of wing-body flight dynamics. Coupling of an in-house CFD solver and a newly developed flapping flight dynamic solver enables the free flight simulation with consideration of both wing-wing interaction and wing-body interaction, and hence a systematic and quantitative evaluation of aerodynamics and flight stability in realistic flying animals. We carried out a systematic computational study on the hovering-and forward-flight of a wing-body moth model and validated the numerical results by comparing with the force-and moment-measurements based on a robotic moth model. Our results indicate that the leading-edge vortex is a universal high-lift/thrust enhancement mechanism in animal flight; and both aerodynamic force and inertial force are important in lift/thrust generation and power requirement, in particular in flight maneuverability.

  12. 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.

  13. DEVELOPING AND IMPLEMENTING A BIRD MIGRATION MONITORING, ASSESSMENT AND PUBLIC OUTREACH PROGRAM FOR YOUR COMMUNITY - THE BIRDCAST PROJECT

    Science.gov (United States)

    The USEPA has developed a technology transfer handbook for the EMPACt BirdCast bird migration monitoring project. The document is essentially a "How-To" Handbook that addresses the planning and implementation steps that were needed to develop, operate and maintain a program simil...

  14. 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

  15. Shifts in Bird Migration Timing in North American Long-Distance and Short-Distance Migrants Are Associated with Climate Change

    Directory of Open Access Journals (Sweden)

    Jay Zaifman

    2017-01-01

    Full Text Available Bird migration is a synchronized event that has evolved over thousands of years. Changing temperatures due to climate change threaten the intricacies of migration timing for birds; however, the extent of these changes has only recently begun to be addressed. Utilizing data from the citizen-science website eBird and historical temperature data, we analyzed bird migration timing in two states warming quickly (Alaska and Maine and one warming gradually (South Carolina. Using linear regressions, we looked at relationships between different temperature indices and year with bird migration timing from 2010 to 2016. Bird migration through all three states, regardless of warming rate, showed similar rates of alterations. Additionally, in every state over half of the birds that had altered migration timing were long-distance migrants. Furthermore, we performed feature selection to determine important factors for changing migration timing of birds. Changes to summer resident and transient bird migration were most influenced by state. In winter resident migration, departure date and length of stay were most influenced by maximum temperature, while arrival date was most associated with minimum temperature. Relationships between changing temperatures and migration timing suggest that global climate change may have consequential effects on all bird migration patterns throughout the United States.

  16. 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.

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

    Science.gov (United States)

    Tian, Huaiyu; 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

    2015-01-06

    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.

  18. European birds adjust their flight initiation distance to road speed limits.

    Science.gov (United States)

    Legagneux, Pierre; Ducatez, Simon

    2013-10-23

    Behavioural responses can help species persist in habitats modified by humans. Roads and traffic greatly affect animals' mortality not only through habitat structure modifications but also through direct mortality owing to collisions. Although species are known to differ in their sensitivity to the risk of collision, whether individuals can change their behaviour in response to this is still unknown. Here, we tested whether common European birds changed their flight initiation distances (FIDs) in response to vehicles according to road speed limit (a known factor affecting killing rates on roads) and vehicle speed. We found that FID increased with speed limit, although vehicle speed had no effect. This suggests that birds adjust their flight distance to speed limit, which may reduce collision risks and decrease mortality maximizing the time allocated to foraging behaviours. Mobility and territory size are likely to affect an individuals' ability to respond adaptively to local speed limits.

  19. 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.

  20. Energy Expenditure and Metabolic Changes of Free-Flying Migrating Northern Bald Ibis

    NARCIS (Netherlands)

    Bairlein, Franz; Fritz, Johannes; Scope, Alexandra; Schwendenwein, Ilse; Stanclova, Gabriela; van Dijk, Gertjan; Meijer, Harro A J; Verhulst, Simon; Dittami, John

    2015-01-01

    Many migrating birds undertake extraordinary long flights. How birds are able to perform such endurance flights of over 100-hour durations is still poorly understood. We examined energy expenditure and physiological changes in Northern Bald Ibis Geronticus eremite during natural flights using birds

  1. Evidence of spread of the emerging infectious disease, finch trichomonosis, by migrating birds.

    Science.gov (United States)

    Lawson, Becki; Robinson, Robert A; Neimanis, Aleksija; Handeland, Kjell; Isomursu, Marja; Agren, Erik O; Hamnes, Inger S; Tyler, Kevin M; Chantrey, Julian; Hughes, Laura A; Pennycott, Tom W; Simpson, Vic R; John, Shinto K; Peck, Kirsi M; Toms, Mike P; Bennett, Malcolm; Kirkwood, James K; Cunningham, Andrew A

    2011-06-01

    Finch trichomonosis emerged in Great Britain in 2005 and led to epidemic mortality and a significant population decline of greenfinches, Carduelis chloris and chaffinches, Fringilla coelebs, in the central and western counties of England and Wales in the autumn of 2006. In this article, we show continued epidemic spread of the disease with a pronounced shift in geographical distribution towards eastern England in 2007. This was followed by international spread to southern Fennoscandia where cases were confirmed at multiple sites in the summer of 2008. Sequence data of the ITS1/5.8S/ITS2 ribosomal region and part of the small subunit (SSU) rRNA gene showed no variation between the British and Fennoscandian parasite strains of Trichomonas gallinae. Epidemiological and historical ring return data support bird migration as a plausible mechanism for the observed pattern of disease spread, and suggest the chaffinch as the most likely primary vector. This finding is novel since, although intuitive, confirmed disease spread by migratory birds is very rare and, when it has been recognised, this has generally been for diseases caused by viral pathogens. We believe this to be the first documented case of the spread of a protozoal emerging infectious disease by migrating birds.

  2. Ecological Causes and Consequences of Intratropical Migration in Temperate-Breeding Migratory Birds.

    Science.gov (United States)

    Stutchbury, Bridget J M; Siddiqui, Raafia; Applegate, Kelly; Hvenegaard, Glen T; Mammenga, Paul; Mickle, Nanette; Pearman, Myrna; Ray, James D; Savage, Anne; Shaheen, Tim; Fraser, Kevin C

    2016-09-01

    New discoveries from direct tracking of temperate-breeding passerines show that intratropical migration (ITM) occurs in a growing number of species, which has important implications for understanding their evolution of migration, population dynamics, and conservation needs. Our large sample size ([Formula: see text]) for purple martins (Progne subis subis) tracked with geolocators to winter sites in Brazil, combined with geolocator deployments at breeding colonies across North America, allowed us to test hypotheses for ITM, something which has not yet been possible to do for other species. ITM in purple martins was not obligate; only 44% of individuals exhibited ITM, and movements were not coordinated in time or space. We found no evidence to support the resource hypothesis; rainfall and temperature experienced by individual birds during their last 2 weeks at their first roost site were similar to conditions at their second roost site after ITM. Birds generally migrated away from the heavily forested northwestern Amazon to less forested regions to the south and east. ITM in this aerial insectivore appears to support the competition-avoidance hypothesis and may be triggered by increasing local density in the core wintering region. Full life cycle models and migratory networks will need to incorporate ITM to properly address seasonal carryover effects and identify which wintering regions are most important for conservation.

  3. From warm to cold: migration of Adélie penguins within Cape Bird, Ross Island

    Science.gov (United States)

    Nie, Yaguang; Sun, Liguang; Liu, Xiaodong; Emslie, Steven D.

    2015-06-01

    Due to their sensitivity to environmental change, penguins in Antarctica are widely used as bio-indicators in paleoclimatic research. On the basis of bio-element assemblages identified in four ornithogenic sediment profiles, we reconstructed the historical penguin population change at Cape Bird, Ross Island, for the past 1600 years. Clear succession of penguin population peaks were observed in different profiles at about 1400 AD, which suggested a high probability of migration within this region. The succession was most obviously marked by a sand layer lasting from 1400 to 1900 AD in one of the analyzed profiles. Multiple physical/chemical parameters indicated this sand layer was not formed in a lacustrine environment, but was marine-derived. Both isostatic subsidence and frequent storms under the colder climatic condition of the Little Ice Age were presumed to have caused the abandonment of the colonies, and we believe the penguins migrated from the coastal area of mid Cape Bird northward and to higher ground as recorded in the other sediment profiles. This migration was an ecological response to global climate change and possible subsequent geological effects in Antarctica.

  4. On the potential roles of ticks and migrating birds in the ecology of West Nile virus

    Directory of Open Access Journals (Sweden)

    Karl Hagman

    2014-01-01

    Full Text Available Background: Mosquitoes are the primary vectors of West Nile virus (WNV. Ticks have, however, been suggested to be potential reservoirs of WNV. To investigate their role in the spread of the virus, ticks, which had been collected from birds migrating northward from Africa to Europe, were analyzed for the potential presence of WNV RNA. Methods: On the Mediterranean islands of Capri and Antikythira, a total of 14,824 birds were captured and investigated from which 747 ticks were collected. Results and conclusions: Most of the identified ticks (93% were nymphs and larvae of Hyalomma marginatum sensu lato (s.l., most of which were or appear to be Hyalomma rufipes. Of these ticks, 729 were individually screened for WNV RNA. None of the ticks was found to be WNV positive. Thus, there was no evidence that H. marginatum s.l. ticks play a role in the spread of WNV from Africa to Europe.

  5. Phenological synchrony of bird migration with tree flowering at desert riparian stopover sites

    Science.gov (United States)

    Kellermann, Jherime L.; van Riper, Charles

    2015-01-01

    Small-bodied songbirds replenish fat reserves during migration at stopover sites where they continually encounter novel and often unpredictable environmental conditions. The ability to select and utilize high quality habitats is critical to survival and fitness. Vegetation phenology is closely linked with emergence of insect prey and may provide valid cues of food availability for stopover habitat selection. Climate change is disrupting phenological synchrony across trophic levels with negative impacts on bird populations. However, whether synchrony or mismatch indicates historic or disrupted systems remains unclear. Many Neotropical migratory songbirds of western North America must cross arid regions where drought conditions related to climate change and human water use are expected to increase. We studied migrant abundance and the diversity (niche breadth) and proportional use of vegetation species as foraging substrates and their synchrony with vegetation flowering during spring migration along the lower Colorado River in the Sonoran Desert of the U.S. and Mexico.

  6. Birds in New York State Have Altered Their Migration Timing and Are Experiencing Different Thermal Regimes While Breeding or on Stopover from 2010 to 2015

    OpenAIRE

    Pudalov, Natalie; Ziatek, Sydney; Jimenez, Ana Gabriela

    2017-01-01

    Migration represents a significant physiological challenge for birds, and increasing ambient temperatures due to global climate change may add to birds’ physiological burden during migration. We analyzed migration timing in a central New York county and two counties in the Adirondack region by using data from the citizen science network, eBird, and correlating it with historical temperature data. Species of birds sighted in Central NY (N=195) and the Adirondack region (N=199) were categorized...

  7. 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

  8. Multiple-factor influences upon feeding flight rates at wading bird colonies (Alias: Are flight-line counts useful?)

    Science.gov (United States)

    Erwin, R.M.; Ogden, J.C.

    1979-01-01

    The temporal patterns of feeding, resting, and reproductive behavior in colonial wading birds have been studied by a number of investigators, both on a short-term (daily) and long-term (annual) basis. In coastal marine environments, activities at colonies are influenced by tides, time of day and phase of the nesting cycle. The purpose of this paper is twofold: (1) to examine the effects of tide, time of day (physical factors), nesting phase, colony site, and species identity (biological factors) on feeding flight rates at breeding colonies and, as a result of this, (2) to evaluate the usefulness of feeding flight counts as an index of the number of nests in the colony. Earlier work suggests that the relationship between the number of individuals flying to and from the nesting colony may be quite consistent with nest numbers. Thus, by monitoring flights from remote locations, observers might obtain relatively accurate census data while minimizing time and disturbance at colonies. Recent concern for the deleterious impact of humans at waterbird colonies underscores the need to investigate alternative census methods.

  9. Spring phenology of ecological productivity contributes to the use of looped migration strategies by birds.

    Science.gov (United States)

    La Sorte, Frank A; Fink, Daniel; Hochachka, Wesley M; DeLong, John P; Kelling, Steve

    2014-10-22

    Migration is a common strategy used by birds that breed in seasonal environments. The patterns and determinants of migration routes, however, remain poorly understood. Recent empirical analyses have demonstrated that the locations of two North America migration flyways (eastern and western) shift seasonally, reflecting the influence of looped migration strategies. For the eastern but not western flyway, seasonal variation in atmospheric circulation has been identified as an explanation. Here, we test an alternative explanation based on the phenology of ecological productivity, which may be of greater relevance in western North America, where phenology is more broadly dictated by elevation. Migrants in the western flyway selected lower-elevation spring routes that were wetter, greener and more productive, and higher-elevation autumn routes that were less green and less productive, but probably more direct. Migrants in the eastern flyway showed little season variation but maintained associations with maximum regional greenness. Our findings suggest the annual phenology of ecological productivity is associated with en route timing in both flyways, and the spring phenology of ecological productivity contributes to the use of looped strategies in the western flyway. This fine-tuned spatial synchronization may be disrupted when changing climate induces a mismatch between food availability and needs. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  10. 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

  11. 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.

  12. Control of respiration in flight muscle from the high-altitude bar-headed goose and low-altitude birds.

    Science.gov (United States)

    Scott, Graham R; Richards, Jeffrey G; Milsom, William K

    2009-10-01

    Bar-headed geese fly at altitudes of up to 9,000 m on their biannual migration over the Himalayas. To determine whether the flight muscle of this species has evolved to facilitate exercise at high altitude, we compared the respiratory properties of permeabilized muscle fibers from bar-headed geese and several low-altitude waterfowl species. Respiratory capacities were assessed for maximal ADP stimulation (with single or multiple inputs to the electron transport system) and cytochrome oxidase excess capacity (with an exogenous electron donor) and were generally 20-40% higher in bar-headed geese when creatine was present. When respiration rates were extrapolated to the entire pectoral muscle mass, bar-headed geese had a higher mass-specific aerobic capacity. This may represent a surplus capacity that counteracts the depressive effects of hypoxia on mitochondrial respiration. However, there were no differences in activity for mitochondrial or glycolytic enzymes measured in homogenized muscle. The [ADP] leading to half-maximal stimulation (K(m)) was approximately twofold higher in bar-headed geese (10 vs. 4-6 microM), and, while creatine reduced K(m) by 30% in this species, it had no effect on K(m) in low-altitude birds. Mitochondrial creatine kinase may therefore contribute to the regulation of oxidative phosphorylation in flight muscle of bar-headed geese, which could promote efficient coupling of ATP supply and demand. However, this was not based on differences in creatine kinase activity in isolated mitochondria or homogenized muscle. The unique differences in bar-headed geese existed without prior exercise or hypoxia exposure and were not a result of phylogenetic history, and may, therefore, be important evolutionary specializations for high-altitude flight.

  13. 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.

  14. 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 ...... pathogens. We show that the risk is not just theoretical and we suggest that these introductions may have a practical public health impact....... 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...

  15. Avian furcula morphology may indicate relationships of flight requirements among birds.

    Science.gov (United States)

    Hui, Clifford A

    2002-03-01

    This study examined furcula (wishbone) shape relative to flight requirements. The furculae from 53 museum specimens in eight orders were measured: 1) three-dimensional shape (SR) as indicated by the ratio of the direct distance between the synostosis interclavicularis and the ligamentous attachment of one of its clavicles to the actual length of the clavicle between those same two points, and 2) curvature within the primary plane (LR) as indicated by the ratio of the length of the clavicle to the sum of the orthogonal distances between the same points using a projected image. Canonical discriminant analysis of these ratios placed the individuals into a) one of four general flight categories and b) one of eight taxonomic orders. The four flight categories were defined as: i) soaring with no flapping, ii) flapping with no soaring, iii) subaqueous (i.e., all wingbeats taking place under water), and iv) partial subaqueous (i.e., wingbeats used for both aerial and submerged flapping). The error rate for placement of the specimens in flight categories was only 26.4%, about half of the error rate for placement in taxonomic orders (51.3%). Subaqueous fliers (penguins, great auks) have furculae that are the most V-shaped. Partial subaqueous fliers (alcids, storm petrels) have furculae that are more U-shaped than the subaqueous fliers but more V-shaped than the aerial flapping fliers. The partial subaqueous fliers have furculae that are also the most anteriorly curved, possibly increasing protraction capability by changing the angle of applied force and increasing attachment area for the origin of the sternobrachialis pectoralis. The increased protraction capability can counteract profile drag, which is greater in water than in air due to the greater density of water. Soaring birds have furculae that are more U-shaped or circular than those of flapping birds and have the smallest range of variation. These results indicate that the shape of the furcula is functionally related

  16. 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.

  17. Increased flight altitudes among migrating golden eagles suggest turbine avoidance at a Rocky Mountain wind installation.

    Science.gov (United States)

    Johnston, Naira N; Bradley, James E; Otter, Ken A

    2014-01-01

    Potential wind-energy development in the eastern Rocky Mountain foothills of British Columbia, Canada, raises concerns due to its overlap with a golden eagle (Aquila chrysaetos) migration corridor. The Dokie 1 Wind Energy Project is the first development in this area and stands as a model for other projects in the area because of regional consistency in topographic orientation and weather patterns. We visually tracked golden eagles over three fall migration seasons (2009-2011), one pre- and two post-construction, to document eagle flight behaviour in relation to a ridge-top wind energy development. We estimated three-dimensional positions of eagles in space as they migrated through our study site. Flight tracks were then incorporated into GIS to ascertain flight altitudes for eagles that flew over the ridge-top area (or turbine string). Individual flight paths were designated to a category of collision-risk based on flight altitude (e.g. flights within rotor-swept height; ≤150 m above ground) and wind speed (winds sufficient for the spinning of turbines; >6.8 km/h at ground level). Eagles were less likely to fly over the ridge-top area within rotor-swept height (risk zone) as wind speed increased, but were more likely to make such crosses under headwinds and tailwinds compared to western crosswinds. Most importantly, we observed a smaller proportion of flights within the risk zone at wind speeds sufficient for the spinning of turbines (higher-risk flights) during post-construction compared to pre-construction, suggesting that eagles showed detection and avoidance of turbines during migration.

  18. Increased flight altitudes among migrating golden eagles suggest turbine avoidance at a Rocky Mountain wind installation.

    Directory of Open Access Journals (Sweden)

    Naira N Johnston

    Full Text Available Potential wind-energy development in the eastern Rocky Mountain foothills of British Columbia, Canada, raises concerns due to its overlap with a golden eagle (Aquila chrysaetos migration corridor. The Dokie 1 Wind Energy Project is the first development in this area and stands as a model for other projects in the area because of regional consistency in topographic orientation and weather patterns. We visually tracked golden eagles over three fall migration seasons (2009-2011, one pre- and two post-construction, to document eagle flight behaviour in relation to a ridge-top wind energy development. We estimated three-dimensional positions of eagles in space as they migrated through our study site. Flight tracks were then incorporated into GIS to ascertain flight altitudes for eagles that flew over the ridge-top area (or turbine string. Individual flight paths were designated to a category of collision-risk based on flight altitude (e.g. flights within rotor-swept height; ≤150 m above ground and wind speed (winds sufficient for the spinning of turbines; >6.8 km/h at ground level. Eagles were less likely to fly over the ridge-top area within rotor-swept height (risk zone as wind speed increased, but were more likely to make such crosses under headwinds and tailwinds compared to western crosswinds. Most importantly, we observed a smaller proportion of flights within the risk zone at wind speeds sufficient for the spinning of turbines (higher-risk flights during post-construction compared to pre-construction, suggesting that eagles showed detection and avoidance of turbines during migration.

  19. 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....

  20. 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.

  1. Flower power: Tree flowering phenology as a settlement cue for migrating birds

    Science.gov (United States)

    McGrath, L.J.; van Riper, Charles; Fontaine, J.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. ?? 2008 The Authors.

  2. Contrasting extreme long-distance migration patterns in bar-tailed godwits

    NARCIS (Netherlands)

    Battley, P.F.; Warnock, N.; Tibbitts, T.L; Gill, R.E.; Piersma, T.; Hassel, C.J.; Douglas, D.C.; Mulcahy, D.M.; Gartell, B.D.; Schuckard, R.; Melville, D.S.; Riegen, A.D.

    2012-01-01

    Migrating birds make the longest non-stop endurance flights in the animal kingdom. Satellite technology is now providingdirect evidence on the lengths and durations of these flights and associated staging episodes for individual birds. Using thistechnology, we compared the migration performance of

  3. Contrasting extreme long-distance migration patterns in bar-tailed godwits Limosa lapponica

    NARCIS (Netherlands)

    Battley, Phil F.; Warnock, Nils; Tibbitts, T. Lee; Gill, Robert E.; Piersma, Theunis; Hassell, Chris J.; Douglas, David C.; Mulcahy, Daniel M.; Gartrell, Brett D.; Schuckard, Rob; Melville, David S.; Riegen, Adrian C.

    Migrating birds make the longest non-stop endurance flights in the animal kingdom. Satellite technology is now providing direct evidence on the lengths and durations of these flights and associated staging episodes for individual birds. Using this technology, we compared the migration performance of

  4. [BEHAVIORAL AND FUNCTIONAL VESTIBULAR DISTURBANCES AFTER SPACE FLIGHT. 2. FISHES, AMPHIBIANS AND BIRDS].

    Science.gov (United States)

    Lychakov, D V

    2016-01-01

    The review contains data on functional shifts in fishes, amphibians and birds caused by changes in the otolith system operation after stay under weightlessness conditions. These data are of theoretical and practical significance and are important to resolve some fundamental problems of vestibulogy. The analysis of the results of space experiments has shown that weightlessness conditions do not exert a substantial impact on formation and functional state of the otolith system in embryonic fishes, amphibians and birds developed during space flight. Weightlessness conditions do pot inhibit embryonic development of lower vertebrates but even have rather beneficial effect on it. This is consistent with conclusions concerning development of mammalian fetuses. The experimental results show that weightlessness can cause similar functional and behavioral vestibular shifts both in lower vertebrates and in mammals. For example, immediately after an orbital flight the vestibuloocular reflex in fish larvae and tadpoles (without lordosis) was stronger than in control individuals. A similar shift of the otolith reflex was observed in the majority of cosmonauts after short-term orbital flights. Immediately after landing adult terrestrial vertebrates, as well as human beings, exhibit lower activity levels, worse equilibrium and coordination of movements. Another interesting finding observed after landing of the cosmic apparatus was an unusual looping character of tadpole swimming. It is supposed that the unusual motor activity of animals as well as appearance of illusions in cosmonauts and astronauts after switching from 1 to 0 g have the same nature and are related to the change in character of otolith organs stimulation. Considering this similarity of vestibular reactions, using animals seems rather perspective. Besides it allows applying in experiments various invasive techniques.

  5. Migration distance and the effect of North Atlantic Oscillation on the spring arrival of birds in Central Europe

    Czech Academy of Sciences Publication Activity Database

    Hubálek, Zdeněk; Čapek, Miroslav

    2008-01-01

    Roč. 57, č. 3 (2008), s. 212-220 ISSN 0139-7893 Institutional research plan: CEZ:AV0Z60930519 Keywords : climate * NAO * phenology * temperature * weather * migration of bird s * wintering area Subject RIV: EH - Ecology, Behaviour Impact factor: 0.522, year: 2008 http://www.ivb.cz/folia/57/3/212_220.pdf

  6. 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

  7. 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

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

    Science.gov (United States)

    Martin, Graham R

    2017-01-01

    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 natural selection

  9. 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

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

    Science.gov (United States)

    Chin, Diana D.; Lentink, David

    2017-01-01

    Birds frequently hop and fly between tree branches to forage. To determine the mechanical energy trade-offs of their bimodal locomotion, we rewarded four Pacific parrotlets with a seed for flying voluntarily between instrumented perches inside a new aerodynamic force platform. By integrating direct measurements of both leg and wing forces with kinematics in a bimodal long jump and flight model, we discovered that parrotlets direct their leg impulse to minimize the mechanical energy needed to forage over different distances and inclinations. The bimodal locomotion model further shows how even a small lift contribution from a single proto-wingbeat would have significantly lengthened the long jump of foraging arboreal dinosaurs. These avian bimodal locomotion strategies can also help robots traverse cluttered environments more effectively. PMID:28560342

  11. Temporal changes in the structure of a plant-frugivore network are influenced by bird migration and fruit availability.

    Science.gov (United States)

    Ramos-Robles, Michelle; Andresen, Ellen; Díaz-Castelazo, Cecilia

    2016-01-01

    Background. Ecological communities are dynamic collections whose composition and structure change over time, making up complex interspecific interaction networks. Mutualistic plant-animal networks can be approached through complex network analysis; these networks are characterized by a nested structure consisting of a core of generalist species, which endows the network with stability and robustness against disturbance. Those mutualistic network structures can vary as a consequence of seasonal fluctuations and food availability, as well as the arrival of new species into the system that might disorder the mutualistic network structure (e.g., a decrease in nested pattern). However, there is no assessment on how the arrival of migratory species into seasonal tropical systems can modify such patterns. Emergent and fine structural temporal patterns are adressed here for the first time for plant-frugivorous bird networks in a highly seasonal tropical environment. Methods. In a plant-frugivorous bird community, we analyzed the temporal turnover of bird species comprising the network core and periphery of ten temporal interaction networks resulting from different bird migration periods. Additionally, we evaluated how fruit abundance and richness, as well as the arrival of migratory birds into the system, explained the temporal changes in network parameters such as network size, connectance, nestedness, specialization, interaction strength asymmetry and niche overlap. The analysis included data from 10 quantitative plant-frugivorous bird networks registered from November 2013 to November 2014. Results. We registered a total of 319 interactions between 42 plant species and 44 frugivorous bird species; only ten bird species were part of the network core. We witnessed a noteworthy turnover of the species comprising the network periphery during migration periods, as opposed to the network core, which did not show significant temporal changes in species composition. Our results

  12. Patterns of bird migration phenology in South Africa suggest northern hemisphere climate as the most consistent driver of change.

    Science.gov (United States)

    Bussière, Elsa M S; Underhill, Les G; Altwegg, Res

    2015-06-01

    Current knowledge of phenological shifts in Palearctic bird migration is largely based on data collected on migrants at their breeding grounds; little is known about the phenology of these birds at their nonbreeding grounds, and even less about that of intra-African migrants. Because climate change patterns are not uniform across the globe, we can expect regional disparities in bird phenological responses. It is also likely that they vary across species, as species show differences in the strength of affinities they have with particular habitats and environments. Here, we examine the arrival and departure of nine Palearctic and seven intra-African migratory species in the central Highveld of South Africa, where the former spend their nonbreeding season and the latter their breeding season. Using novel analytical methods based on bird atlas data, we show phenological shifts in migration of five species - red-backed shrike, spotted flycatcher, common sandpiper, white-winged tern (Palearctic migrants), and diederik cuckoo (intra-African migrant) - between two atlas periods: 1987-1991 and 2007-2012. During this time period, Palearctic migrants advanced their departure from their South African nonbreeding grounds. This trend was mainly driven by waterbirds. No consistent changes were observed for intra-African migrants. Our results suggest that the most consistent drivers of migration phenological shifts act in the northern hemisphere, probably at the breeding grounds. © 2015 John Wiley & Sons Ltd.

  13. Flight calls and orientation

    DEFF Research Database (Denmark)

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

    2008-01-01

      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...... 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...

  14. 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

  15. 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.

  16. Candidate genes for migration do not distinguish migratory and non-migratory birds.

    Science.gov (United States)

    Lugo Ramos, Juan S; Delmore, Kira E; Liedvogel, Miriam

    2017-07-01

    Migratory traits in birds have been shown to have a strong heritable component and several candidate genes have been suggested to control these migratory traits. To investigate if the genetic makeup of one or a set of these candidate genes can be used to identify a general pattern between migratory and non-migratory birds, we extracted genomic sequence data for 25 hypothesised candidate genes for migration from 70 available genomes across all orders of Aves and characterised sequence divergence between migratory and non-migratory phenotypes. When examining each gene separately across all species, we did not identify any genetic variants in candidate genes that distinguished migrants from non-migrants; any resulting pattern was driven by the phylogenetic signal. This was true for each gene analysed independently, but also for concatenated sequence alignments of all candidate genes combined. We also attempted to distinguish between migrant and non-migrants using structural features at four candidate genes that have previously been reported to show associated with migratory behaviour but did not pick up a signal for migratory phenotype here either. Finally, a screen for dN/dS ratio across all focal candidate genes to probe for putative features of selection did not uncover a pattern, though this might not be expected given the broad phylogenetic scale used here. Our study demonstrates the potential of public genomic data to test for general patterns of migratory gene candidates in a cross-species comparative context, and raise questions on the applicability of candidate gene approaches in a macro-evolutionary context to understand the genetic architecture of migratory behaviour.

  17. 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.

  18. Birds in New York State Have Altered Their Migration Timing and Are Experiencing Different Thermal Regimes While Breeding or on Stopover from 2010 to 2015

    Directory of Open Access Journals (Sweden)

    Natalie Pudalov

    2017-01-01

    Full Text Available Migration represents a significant physiological challenge for birds, and increasing ambient temperatures due to global climate change may add to birds’ physiological burden during migration. We analyzed migration timing in a central New York county and two counties in the Adirondack region by using data from the citizen science network, eBird, and correlating it with historical temperature data. Species of birds sighted in Central NY (N=195 and the Adirondack region (N=199 were categorized into year-round residents and one- and two-stopover groupings based on eBird observations. Using linear regressions, we looked at various relationships between temperature and variables relating to birds’ migration across 2010–2015. Of the total 195 species used within this data in Central NY, 35 species showed some alteration in their migration timing or in the temperature regime they experienced while breeding or on migration stopover. In the Adirondack region, of the total 199 species used within this dataset, 43 species showed some alteration in their migration timing or experienced significantly colder or warmer temperatures while breeding or on migration stopover during 2010–2015. Additionally, many of the bird species affected by temperature changes in the state of New York and those that altered migration timing tended to be long-distance migrants.

  19. 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.

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

    Directory of Open Access Journals (Sweden)

    Lisa C Davenport

    Full Text Available 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.

  1. Migration path annotation: cross-continental study of migration-flight response to environmental conditions.

    Science.gov (United States)

    Mandel, James T; Bohrer, Gil; Winkler, David W; Barber, David R; Houston, C Stuart; Bildstein, Keith L

    2011-09-01

    Understanding the movements of animals is pivotal for understanding their ecology and predicting their survival in the face of rapid global changes to climate, land use, and habitats, thus facilitating more effective habitat management. Migration by flying animals is an extreme form of movement that may be especially influenced by weather. With satellite telemetry studies, and the growing availability of information about the Earth's weather and land surface conditions, many data are collected that can advance our understanding about the mechanisms that shape migrations. We present the track annotation approach for movement data analysis using information about weather from the North American Reanalysis data set, a publicly available, regional, high-resolution model-observation hybrid product, and about topography, from a publicly available high-resolution digital elevation model (DEM). As a case study, we present the analysis of the response to environmental conditions in three contrasting populations of Turkey Vultures (Cathartes aura) across North America, tracked with a three-dimensional GPS-based sensor. Two populations in the east and west coasts of the United States responded similarly to weather, indicating use of both slope and thermal soaring. Continental-interior, "Plains populations," exhibited a different migratory pattern primarily indicative of thermal soaring. These differences help us understand the constraints and behaviors of soaring migrants. The track annotation approach allowed large-scale comparative study of movement in an important migratory species, and will enable similar studies at local to global scales.

  2. Strategic flight assignment approach based on multi-objective parallel evolution algorithm with dynamic migration interval

    Directory of Open Access Journals (Sweden)

    Zhang Xuejun

    2015-04-01

    Full Text Available The continuous growth of air traffic has led to acute airspace congestion and severe delays, which threatens operation safety and cause enormous economic loss. Flight assignment is an economical and effective strategic plan to reduce the flight delay and airspace congestion by reasonably regulating the air traffic flow of China. However, it is a large-scale combinatorial optimization problem which is difficult to solve. In order to improve the quality of solutions, an effective multi-objective parallel evolution algorithm (MPEA framework with dynamic migration interval strategy is presented in this work. Firstly, multiple evolution populations are constructed to solve the problem simultaneously to enhance the optimization capability. Then a new strategy is proposed to dynamically change the migration interval among different evolution populations to improve the efficiency of the cooperation of populations. Finally, the cooperative co-evolution (CC algorithm combined with non-dominated sorting genetic algorithm II (NSGA-II is introduced for each population. Empirical studies using the real air traffic data of the Chinese air route network and daily flight plans show that our method outperforms the existing approaches, multi-objective genetic algorithm (MOGA, multi-objective evolutionary algorithm based on decomposition (MOEA/D, CC-based multi-objective algorithm (CCMA as well as other two MPEAs with different migration interval strategies.

  3. Life history, predation and flight initiation distance in a migratory bird.

    Science.gov (United States)

    Møller, A P

    2014-06-01

    Life-history trade-offs occur as a consequence of the compromise between maximization of different components such as the size and the number of clutches. Flight initiation distance (FID) potentially constitutes a general proximate factor influencing such trade-offs reflecting the risks that individuals take. Therefore, greater investment in reproduction occurs at a higher risk of death, resulting in selection for efficient flight morphology. I analysed long-term data on FID in a population of barn swallows Hirundo rustica during 1984-2013 with 2196 records of FID for 1789 individuals. FID had a repeatability of 0.62 (SE = 0.04) and a heritability of 0.48 (SE = 0.07). FID varied between individuals and sites, and it increased over time as climate ameliorated. FID showed a U-shaped relationship with age, with young and very old individuals having the longest FIDs. Barn swallows that arrived early from spring migration, started to breed early and produced many fledglings had the longest FID. Individuals with the longest tails had the longest FID, and individuals with the shortest aspect ratios and wing loadings had the longest FID. Individuals that died from predation had shorter FID than survivors. These findings are consistent with the hypothesis that FID relates directly to life history, with longer FIDs being associated with smaller levels of risk-taking. © 2014 The Author. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

  4. Seasonal patterns in δ2 H values of multiple tissues from Andean birds provide insights into elevational migration.

    Science.gov (United States)

    Villegas, Mariana; Newsome, Seth D; Blake, John G

    2016-12-01

    Elevational migration is a widespread phenomenon in tropical avifauna but it is difficult to identify using traditional approaches. Hydrogen isotope (δ 2 H) values of precipitation decrease with elevation so δ 2 H analysis of multiple bird tissues with different isotopic incorporation rates may be a reliable method for characterizing seasonal elevational migration. Here we compare δ 2 H values in metabolically inert (feathers and claws) and metabolically active (whole blood) tissues to examine whether an upslope migration occurs prior to the breeding season in the Yungas Manakin (Chiroxiphia boliviana). We compare results from C. boliviana with data from a known elevational migrant, the Streak-necked Flycatcher (Mionectes striaticollis). Opposite to our expectations, tissue δ 2 H values increased over time, largely reflecting seasonal patterns in precipitation δ 2 H rather than elevational effects; linear mixed-effects models with strongest support included ordinal date, tissue type, and elevation. This seasonal increase in precipitation δ 2 H is a general phenomenon in both tropical and temperate mountain ranges. We use these data to propose a hypothetical framework that predicts different patterns in tissue δ 2 H values collected in different seasons from residents and elevational migrants. This framework can serve as a reference for future studies that assess elevational migration in birds and other animals. © 2016 by the Ecological Society of America.

  5. Potential for an Arctic-breeding migratory bird to adjust spring migration phenology to Arctic amplification.

    Science.gov (United States)

    Lameris, Thomas K; Scholten, Ilse; Bauer, Silke; Cobben, Marleen M P; Ens, Bruno J; Nolet, Bart A

    2017-10-01

    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 of local spring, consequently reducing individual fitness and potentially even population levels. We used a dynamic state variable model to study whether Arctic long-distance migrants can advance their migratory schedules under climate warming scenarios which include Arctic amplification, and whether such an advancement is constrained by fuel accumulation or the ability to anticipate climatic changes. Our model predicts that barnacle geese Branta leucopsis suffer from considerably reduced reproductive success with increasing Arctic amplification through mistimed arrival, when they cannot anticipate a more rapid progress of Arctic spring from their wintering grounds. When geese are able to anticipate a more rapid progress of Arctic spring, they are predicted to advance their spring arrival under Arctic amplification up to 44 days without any reproductive costs in terms of optimal condition or timing of breeding. Negative effects of mistimed arrival on reproduction are predicted to be somewhat mitigated by increasing summer length under warming in the Arctic, as late arriving geese can still breed successfully. We conclude that adaptation to Arctic amplification may rather be constrained by the (un)predictability of changes in the Arctic spring than by the time available for fuel accumulation. Social migrants like geese tend to have a high behavioural plasticity regarding stopover site choice and migration schedule, giving them the potential to adapt to future climate changes on their flyway. © 2017 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.

  6. 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.

  7. 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.

  8. Experimental reduction of winter food decreases body condition and delays migration in a long-distance migratory bird.

    Science.gov (United States)

    Cooper, Nathan W; Sherry, Thomas W; Marra, Peter P

    2015-07-01

    Many tropical habitats experience pronounced dry seasons, during which arthropod food availability declines, potentially limiting resident and migratory animal populations. In response to declines in food, individuals may attempt to alter their space use to enhance access to food resources, but may be socially constrained from doing so by con- and heterospecifics. If social constraints exist, food declines should result in decreased body condition. In migratory birds, correlational evidence suggests a link between body condition and migration timing. Poor body condition and delayed migration may, in turn, impact fitness in subsequent seasons via carry-over effects. To determine if winter food availability affects space use, inter- and intraspecific competition, body composition (i.e., mass, fat, and pectoral muscle), and migration timing, we experimentally decreased food availability on individual American Redstart (Setophaga ruticilla) territories in high-quality mangrove habitat. Redstarts on control territories experienced -40% loss of food due to the seasonal nature of the environment. Redstarts on experimental territories experienced -80% declines in food, which closely mimicked natural declines in nearby, low-quality, scrub habitat. Individuals on food-reduced territories did not expand their territories locally, but instead either became non-territorial "floaters" or remained on territory. Regardless of territorial status, food-reduced American Redstarts all deposited fat compared to control birds. Fat deposits provide insurance against the risk of starvation, but, for American Redstarts, came at the expense of maintaining pectoral muscle. Subsequently, food-reduced American Redstarts experienced, on average, a one-week delay in departure on spring migration, likely due to the loss of pectoral muscle. Thus, our results demonstrate experimentally, for the first time, that declines in winter food availability can result in a fat-muscle trade-off, which, in

  9. The function of migratory bird calls

    DEFF Research Database (Denmark)

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

    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...... allowed to settle and express migratory restlessness for at least 30 minutes. Secondly, the flight simulation axis (e.g. E-W or N-S) with the largest angle relative to the bird's migration course was chosen and "flights" of simulated calling conspecifics or the "ding" sound along this axis continued...

  10. Dissemination of spotted fever rickettsia agents in Europe by migrating birds.

    Science.gov (United States)

    Elfving, Karin; Olsen, Björn; Bergström, Sven; Waldenström, Jonas; Lundkvist, Ake; Sjöstedt, Anders; Mejlon, Hans; Nilsson, Kenneth

    2010-01-05

    Migratory birds are known to play a role as long-distance vectors for many microorganisms. To investigate whether this is true of rickettsial agents as well, we characterized tick infestation and gathered ticks from 13,260 migratory passerine birds in Sweden. A total of 1127 Ixodes spp. ticks were removed from these birds and the extracted DNA from 957 of them was available for analyses. The DNA was assayed for detection of Rickettsia spp. using real-time PCR, followed by DNA sequencing for species identification. Rickettsia spp. organisms were detected in 108 (11.3%) of the ticks. Rickettsia helvetica, a spotted fever rickettsia associated with human infections, was predominant among the PCR-positive samples. In 9 (0.8%) of the ticks, the partial sequences of 17kDa and ompB genes showed the greatest similarity to Rickettsia monacensis, an etiologic agent of Mediterranean spotted fever-like illness, previously described in southern Europe as well as to the Rickettsia sp.IrITA3 strain. For 15 (1.4%) of the ticks, the 17kDa, ompB, gltA and ompA genes showed the greatest similarity to Rickettsia sp. strain Davousti, Rickettsia japonica and Rickettsia heilongjiangensis, all closely phylogenetically related, the former previously found in Amblyomma tholloni ticks in Africa and previously not detected in Ixodes spp. ticks. The infestation prevalence of ticks infected with rickettsial organisms was four times higher among ground foraging birds than among other bird species, but the two groups were equally competent in transmitting Rickettsia species. The birds did not seem to serve as reservoir hosts for Rickettsia spp., but in one case it seems likely that the bird was rickettsiemic and that the ticks had acquired the bacteria from the blood of the bird. In conclusion, migratory passerine birds host epidemiologically important vector ticks and Rickettsia species and contribute to the geographic distribution of spotted fever rickettsial agents and their diseases.

  11. Wild bird migration across the Qinghai-Tibetan plateau: a transmission route for highly pathogenic H5N1.

    Science.gov (United States)

    Prosser, Diann J; Cui, Peng; Takekawa, John Y; Tang, Mingjie; Hou, Yuansheng; Collins, Bridget M; Yan, Baoping; Hill, Nichola J; Li, Tianxian; Li, Yongdong; Lei, Fumin; Guo, Shan; Xing, Zhi; He, Yubang; Zhou, Yuanchun; Douglas, David C; Perry, William M; Newman, Scott H

    2011-03-09

    Qinghai Lake in central China has been at the center of debate on whether wild birds play a role in circulation of highly pathogenic avian influenza virus H5N1. In 2005, an unprecedented epizootic at Qinghai Lake killed more than 6000 migratory birds including over 3000 bar-headed geese (Anser indicus). H5N1 subsequently spread to Europe and Africa, and in following years has re-emerged in wild birds along the Central Asia flyway several times. To better understand the potential involvement of wild birds in the spread of H5N1, we studied the movements of bar-headed geese marked with GPS satellite transmitters at Qinghai Lake in relation to virus outbreaks and disease risk factors. We discovered a previously undocumented migratory pathway between Qinghai Lake and the Lhasa Valley of Tibet where 93% of the 29 marked geese overwintered. From 2003-2009, sixteen outbreaks in poultry or wild birds were confirmed on the Qinghai-Tibet Plateau, and the majority were located within the migratory pathway of the geese. Spatial and temporal concordance between goose movements and three potential H5N1 virus sources (poultry farms, a captive bar-headed goose facility, and H5N1 outbreak locations) indicated ample opportunities existed for virus spillover and infection of migratory geese on the wintering grounds. Their potential as a vector of H5N1 was supported by rapid migration movements of some geese and genetic relatedness of H5N1 virus isolated from geese in Tibet and Qinghai Lake. This is the first study to compare phylogenetics of the virus with spatial ecology of its host, and the combined results suggest that wild birds play a role in the spread of H5N1 in this region. However, the strength of the evidence would be improved with additional sequences from both poultry and wild birds on the Qinghai-Tibet Plateau where H5N1 has a clear stronghold.

  12. Wild bird migration across the Qinghai-Tibetan plateau: a transmission route for highly pathogenic H5N1.

    Directory of Open Access Journals (Sweden)

    Diann J Prosser

    Full Text Available BACKGROUND: Qinghai Lake in central China has been at the center of debate on whether wild birds play a role in circulation of highly pathogenic avian influenza virus H5N1. In 2005, an unprecedented epizootic at Qinghai Lake killed more than 6000 migratory birds including over 3000 bar-headed geese (Anser indicus. H5N1 subsequently spread to Europe and Africa, and in following years has re-emerged in wild birds along the Central Asia flyway several times. METHODOLOGY/PRINCIPAL FINDINGS: To better understand the potential involvement of wild birds in the spread of H5N1, we studied the movements of bar-headed geese marked with GPS satellite transmitters at Qinghai Lake in relation to virus outbreaks and disease risk factors. We discovered a previously undocumented migratory pathway between Qinghai Lake and the Lhasa Valley of Tibet where 93% of the 29 marked geese overwintered. From 2003-2009, sixteen outbreaks in poultry or wild birds were confirmed on the Qinghai-Tibet Plateau, and the majority were located within the migratory pathway of the geese. Spatial and temporal concordance between goose movements and three potential H5N1 virus sources (poultry farms, a captive bar-headed goose facility, and H5N1 outbreak locations indicated ample opportunities existed for virus spillover and infection of migratory geese on the wintering grounds. Their potential as a vector of H5N1 was supported by rapid migration movements of some geese and genetic relatedness of H5N1 virus isolated from geese in Tibet and Qinghai Lake. CONCLUSIONS/SIGNIFICANCE: This is the first study to compare phylogenetics of the virus with spatial ecology of its host, and the combined results suggest that wild birds play a role in the spread of H5N1 in this region. However, the strength of the evidence would be improved with additional sequences from both poultry and wild birds on the Qinghai-Tibet Plateau where H5N1 has a clear stronghold.

  13. Variation of basal EROD activities in ten passerine bird species--relationships with diet and migration status.

    Science.gov (United States)

    Rainio, Miia J; Kanerva, Mirella; Wahlberg, Niklas; Nikinmaa, Mikko; Eeva, Tapio

    2012-01-01

    Inter-specific differences in animal defence mechanisms against toxic substances are currently poorly understood. The ethoxyresorufin-O-deethylase (EROD) enzyme plays an important role in defence against toxic chemicals in a wide variety of animals, and it is an important biomarker for environmental contamination. We compared basal hepatic EROD activity levels among ten passerine species to see if there is inter-specific variation in enzyme activity, especially in relation to their diet and migration status. Migratory insectivores showed higher EROD activity compared to granivores. We hypothesize that the variable invertebrate diet of migratory insectivores contains a wider range of natural toxins than the narrower diet of granivores. This may have affected the evolution of mixed function oxidases (MFO) system and enzyme activities. We further tested whether metabolic rates or relative liver size were associated with the variation in detoxification capacity. We found no association between EROD activity and relative (per mass unit) basal metabolic rate (BMR). Instead, EROD activity and relative liver mass (% of body mass) correlated positively, suggesting that a proportionally large liver also functions efficiently. Our results suggest that granivores and non-migratory birds may be more vulnerable to environmental contaminants than insectivores and migratory birds. The diet and migration status, however, are phylogenetically strongly connected to each other, and their roles cannot be fully separated in our analysis with only ten passerine species.

  14. Migratory connectivity and population-specific migration routes in a long-distance migratory bird

    NARCIS (Netherlands)

    Trierweiler, Christiane; Klaassen, Raymond H.G.; Drent, Rudi H.; Exo, Klaus-Michael; Komdeur, Jan; Bairlein, Franz; Koks, Ben J.

    2014-01-01

    Knowledge about migratory connectivity, the degree to which individuals from the same breeding site migrate to the same wintering site, is essential to understand processes affecting populations of migrants throughout the annual cycle. Here, we study the migration system of a long-distance migratory

  15. 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

  16. The magnetic map sense and its use in fine-tuning the migration programme of birds.

    Science.gov (United States)

    Heyers, D; Elbers, D; Bulte, M; Bairlein, F; Mouritsen, H

    2017-07-01

    The Earth's magnetic field is one of several natural cues, which migratory birds can use to derive directional ("compass") information for orientation on their biannual migratory journeys. Moreover, magnetic field effects on prominent aspects of the migratory programme of birds, such as migratory restlessness behaviour, fuel deposition and directional orientation, implicate that geomagnetic information can also be used to derive positional ("map") information. While the magnetic "compass" in migratory birds is likely to be based on radical pair-forming molecules embedded in their visual system, the sensory correlates underlying a magnetic "map" sense currently remain elusive. Behavioural, physiological and neurobiological findings indicate that the sensor is most likely innervated by the ophthalmic branch of the trigeminal nerve and based on magnetic iron particles. Information from this unknown sensor is neither necessary nor sufficient for a functional magnetic compass, but instead could contribute important components of a multifactorial "map" for global positioning. Positional information could allow migratory birds to make vitally important dynamic adaptations of their migratory programme at any relevant point during their journeys.

  17. The Difference That Data Make: Examining Bird Migration Data to Build Scientific Skills

    Science.gov (United States)

    Sturner, Kelly; Lucci, Karen

    2015-01-01

    This inquiry-based activity for high school students introduces concepts of ecology and the importance of data analysis to science. Using an investigative case, students generate independent questions about birds, access Cornell Lab of Ornithology online resources to collect data, organize and graph data using Excel, and make claims based on…

  18. Heavy fall of migrating land-birds on board of a ship off Central America

    NARCIS (Netherlands)

    Roselaar, C.S.

    1976-01-01

    Between 4 and 7 October 1973, during a spell of unfavourable weather, 85 North American migratory birds were found dead on board a ship sailing between Costa Rica and Belize and in the roads of Belize. They were donated to the Institute of Taxonomic Zoology, University of Amsterdam, where they were

  19. A sport-physiological perspective on bird migration : Evidence for flight-induced muscle damage

    NARCIS (Netherlands)

    Guglielmo, C; Piersma, T; Williams, TD; Williams, Tony D.

    Exercise-induced muscle damage is a well-described consequence of strenuous exercise, but its potential importance in the evolution of animal activity patterns is unknown. We used plasma creatine kinase (CK) activity as an indicator of muscle damage to investigate whether the high intensity,

  20. Consistency in long-distance bird migration: contrasting patterns in time and space for two raptors

    NARCIS (Netherlands)

    Vardanis, Yannis; Nilsson, Jan-Ake; Klaassen, Raymond H. G.; Strandberg, Roine; Alerstam, Thomas

    As the evolutionary responses to environmental change depend on selection acting on individual differences, disentangling within- and between-individual variation becomes imperative. In animal migration research, multiyear tracks are thus needed to estimate the individual consistency of phenotypic

  1. Flight speeds of swifts (Apus apus): seasonal differences smaller than expected.

    Science.gov (United States)

    Henningsson, P; Karlsson, H; Bäckman, J; Alerstam, T; Hedenström, A

    2009-07-07

    We have studied the nocturnal flight behaviour of the common swift (Apus apus L.), by the use of a tracking radar. Birds were tracked from Lund University in southern Sweden during spring migration, summer roosting flights and autumn migration. Flight speeds were compared with predictions from flight mechanical and optimal migration theories. During spring, flight speeds were predicted to be higher than during both summer and autumn due to time restriction. In such cases, birds fly at a flight speed that maximizes the overall speed of migration. For summer roosting flights, speeds were predicted to be lower than during both spring and autumn since the predicted flight speed is the minimum power speed that involves the lowest energy consumption per unit time. During autumn, we expected flight speeds to be higher than during summer but lower than during spring since the expected flight speed is the maximum range speed, which involves the lowest energy consumption per unit distance. Flight speeds during spring were indeed higher than during both summer and autumn, which indicates time-selected spring migration. Speeds during autumn migration were very similar to those recorded during summer roosting flights. The general result shows that swifts change their flight speed between different flight behaviours to a smaller extent than expected. Furthermore, the difference between flight speeds during migration and roosting among swifts was found to be less pronounced than previously recorded.

  2. 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.

  3. Inferring the potential risks of H7N9 infection by spatiotemporally characterizing bird migration and poultry distribution in eastern China.

    Science.gov (United States)

    Shi, Benyun; Xia, Shang; Yang, Guo-Jing; Zhou, Xiao-Nong; Liu, Jiming

    2013-05-03

    In view of the rapid geographic spread and the increasing number of confirmed cases of novel influenza A(H7N9) virus infections in eastern China, we developed a diffusion model to spatiotemporally characterize the impacts of bird migration and poultry distribution on the geographic spread of H7N9 infection. Three types of infection risks were estimated for 12 weeks, from February 4 to April 28, 2013, including (i) the risk caused by bird migration, (ii) the risk caused by poultry distribution, and (iii) the integrated risk caused by both bird migration and poultry distribution. To achieve this, we first developed a method for estimating the likelihood of bird migration based on available environmental and meteorological data. Then, we adopted a computational mobility model to estimate poultry distribution based on annual poultry production and consumption of each province/municipality. Finally, the spatiotemporal risk maps were created based on the integrated impacts of both bird migration and poultry distribution. In the study of risk estimation caused by bird migration, the likelihood matrix was estimated based on the 7-day temperature, from February 4 to April 28, 2013. It was found the estimated migrant birds mainly appear in the southeastern provinces of Zhejiang, Shanghai and Jiangsu during Weeks 1 to 4, and Week 6, followed by appearing in central eastern provinces of Shandong, Hebei, Beijing, and Tianjin during Weeks 7 to 9, and finally in northeastern provinces of Liaoning, Jilin, and Heilongjiang during Weeks 10 to 12.In the study of risk caused by poultry distribution, poultry distribution matrix was created to show the probability of poultry distribution. In spite of the fact that the majority of the initial infections were reported in Shanghai and Jiangsu, the relative risk of H7N9 infection estimated based on the poultry distribution model predicted that Jiangsu may have a slightly higher likelihood of H7N9 infection than those in Zhejiang and

  4. 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

  5. Why is timing of bird migration advancing when individuals are not?

    Science.gov (United States)

    Gill, Jennifer A; Alves, José A; Sutherland, William J; Appleton, Graham F; Potts, Peter M; Gunnarsson, Tómas G

    2014-01-07

    Recent advances in spring arrival dates have been reported in many migratory species but the mechanism driving these advances is unknown. As population declines are most widely reported in species that are not advancing migration, there is an urgent need to identify the mechanisms facilitating and constraining these advances. Individual plasticity in timing of migration in response to changing climatic conditions is commonly proposed to drive these advances but plasticity in individual migratory timings is rarely observed. For a shorebird population that has significantly advanced migration in recent decades, we show that individual arrival dates are highly consistent between years, but that the arrival dates of new recruits to the population are significantly earlier now than in previous years. Several mechanisms could drive advances in recruit arrival, none of which require individual plasticity or rapid evolution of migration timings. In particular, advances in nest-laying dates could result in advanced recruit arrival, if benefits of early hatching facilitate early subsequent spring migration. This mechanism could also explain why arrival dates of short-distance migrants, which generally return to breeding sites earlier and have greater scope for advance laying, are advancing more rapidly than long-distance migrants.

  6. Classroom Bird Feeding: Giving Flight to the Imaginations of 4- and 5-Year-Olds!

    Science.gov (United States)

    McLennan, Deanna Pecaski

    2012-01-01

    In this article, the author describes how placing a plastic, gazebo-style bird feeder outside the classroom windows one cold autumn morning had been a catalyst for capturing and inspiring the children's imaginations. This empowered them to explore self-directed activities that resulted in meaningful, collaborative learning for most of the school…

  7. Repeats, returns, and estimated flight ranges of neotropical migratory birds in Utah riparian habitat

    Science.gov (United States)

    Dan A. Roberts; Jimmie R. Parrish; Frank P. Howe

    2005-01-01

    We present data on capture and recapture of neotropical migrants at constant-effort mist net sampling locations in Utah between 1994 and 2002. Data were collected in accordance with MAPS (Monitoring Avian Productivity and Survivorship) protocols. Since 1994, a total of 23,789 birds have been captured (i.e., total captures include new captures, recaptures, and unbanded...

  8. Integrating concepts and technologies to advance the study of bird migration

    NARCIS (Netherlands)

    Robinson, W.D.; Bowlin, M.S.; Bisson, I.; Shamoun-Baranes, J.; Thorup, K.; Diehl, R.H.; Kunz, T.H.; Mabey, S.; Winkler, D.W.

    2010-01-01

    Recent technological innovation has opened new avenues in migration research - for instance, by allowing individual migratory animals to be followed over great distances and long periods of time, as well as by recording physiological information. Here, we focus on how technology - specifically

  9. Migration distance is positively associated with sex-linked genetic diversity in passerine birds

    Czech Academy of Sciences Publication Activity Database

    Gohli, J.; Lifjeld, J. T.; Albrecht, Tomáš

    2016-01-01

    Roč. 28, č. 1 (2016), s. 42-52 ISSN 0394-9370 R&D Projects: GA ČR(CZ) GAP506/12/2472 Institutional support: RVO:68081766 Keywords : autosomes * female promiscuity * introns * seasonal migration * Z chromosome Subject RIV: EG - Zoology Impact factor: 1.582, year: 2016

  10. Radar analysis of fall bird migration stopover sites in the northeastern U.S.

    Science.gov (United States)

    Buler, Jeffrey J.; Dawson, Deanna K.

    2014-01-01

    The national network of weather surveillance radars (WSR-88D) detects flying birds and is a useful remote-sensing tool for ornithological study. We used data collected during fall 2008 and 2009 by 16 WSR-88D radars in the northeastern U.S. to quantify the spatial distribution of landbirds during migratory stopover. We geo-referenced estimates based on radar reflectivity, of the density of migrants aloft at their abrupt evening exodus from daytime stopover sites, to the approximate locations from which they emerged. We classified bird stopover use by the magnitude and variation of radar reflectivity across nights; areas were considered “important” stopover sites for conservation if bird density was consistently high. We developed statistical models that predict potentially important stopover sites across the region, based on land cover, ground elevation, and geographic location. Large areas of regionally important stopover sites were located along the coastlines of Long Island Sound, throughout the Delmarva Peninsula, in areas surrounding Baltimore and Washington, along the western edge of the Adirondack Mountains, and within the Appalachian Mountains of southwestern Virginia and West Virginia. Locally important stopover sites generally were associated with deciduous forests embedded within landscapes dominated by developed or agricultural lands, or near the shores of major water bodies. Preserving or enhancing patches of natural habitat, particularly deciduous forests, in developed or agricultural landscapes and along major coastlines could be a priority for conservation plans addressing the stopover requirements of migratory landbirds in the northeastern U.S. Our maps of important stopover sites can be used to focus conservation efforts and can serve as a sampling frame for fieldwork to validate radar observations or for ecological studies of landbirds on migratory stopover.

  11. Water and heat balance during flight in the rose-colored starling (Sturnus roseus)

    NARCIS (Netherlands)

    Engel, Sophia; Biebach, Herbert; Visser, G. Henk

    2006-01-01

    Water imbalance during flight is considered to be a potentially limiting factor for flight ranges in migrating birds, but empirical data are scarce. We studied flights under controlled ambient conditions with rose-colored starlings in a wind tunnel. In one experiment, we measured water fluxes with

  12. 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.

  13. 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.

  14. Quantifying full phenological event distributions reveals simultaneous advances, temporal stability and delays in spring and autumn migration timing in long-distance migratory birds.

    Science.gov (United States)

    Miles, Will T S; Bolton, Mark; Davis, Peter; Dennis, Roy; Broad, Roger; Robertson, Iain; Riddiford, Nick J; Harvey, Paul V; Riddington, Roger; Shaw, Deryk N; Parnaby, David; Reid, Jane M

    2017-04-01

    Phenological changes in key seasonally expressed life-history traits occurring across periods of climatic and environmental change can cause temporal mismatches between interacting species, and thereby impact population and community dynamics. However, studies quantifying long-term phenological changes have commonly only measured variation occurring in spring, measured as the first or mean dates on which focal traits or events were observed. Few studies have considered seasonally paired events spanning spring and autumn or tested the key assumption that single convenient metrics accurately capture entire event distributions. We used 60 years (1955-2014) of daily bird migration census data from Fair Isle, Scotland, to comprehensively quantify the degree to which the full distributions of spring and autumn migration timing of 13 species of long-distance migratory bird changed across a period of substantial climatic and environmental change. In most species, mean spring and autumn migration dates changed little. However, the early migration phase (≤10th percentile date) commonly got earlier, while the late migration phase (≥90th percentile date) commonly got later. Consequently, species' total migration durations typically lengthened across years. Spring and autumn migration phenologies were not consistently correlated within or between years within species and hence were not tightly coupled. Furthermore, different metrics quantifying different aspects of migration phenology within seasons were not strongly cross-correlated, meaning that no single metric adequately described the full pattern of phenological change. These analyses therefore reveal complex patterns of simultaneous advancement, temporal stability and delay in spring and autumn migration phenologies, altering species' life-history structures. Additionally, they demonstrate that this complexity is only revealed if multiple metrics encompassing entire seasonal event distributions, rather than single

  15. Migrating birds : assessment of impact on 915-MHz radar wind profiler performance at the Atmospheric Radiation Measurement Program's southern great plains

    International Nuclear Information System (INIS)

    Pekour, M. S.

    2002-01-01

    The U. S. Department of Energy's Atmospheric Radiation Measurement Program is running a small network of 915-MHz radar wind profilers (RWPs) at its Southern Great Plains Cloud and Radiation Testbed site in northern Oklahoma and southern Kansas. Seasonal migration of passerines may cause significant interference with the operation of 915-MHz RWPs. The extent of this ''bird jamming'' depends on the radar's parameters, the place of deployment, the season, and the time of day. This poster presents a new diagnostic method for detecting possible bird contamination in RWP data, along with an evaluation of the method using a three-year data set for two RWPs

  16. Coloniality and migration are related to selection on MHC genes in birds.

    Science.gov (United States)

    Minias, Piotr; Whittingham, Linda A; Dunn, Peter O

    2017-02-01

    The major histocompatibility complex (MHC) plays a key role in pathogen recognition as a part of the vertebrate adaptive immune system. The great diversity of MHC genes in natural populations is maintained by different forms of balancing selection and its strength should correlate with the diversity of pathogens to which a population is exposed and the rate of exposure. Despite this prediction, little is known about how life-history characteristics affect selection at the MHC. Here, we examined whether the strength of balancing selection on MHC class II genes in birds (as measured with nonsynonymous nucleotide substitutions, dN) was related to their social or migratory behavior, two life-history characteristics correlated with pathogen exposure. Our comparative analysis indicated that the rate of nonsynonymous substitutions was higher in colonial and migratory species than solitary and resident species, suggesting that the strength of balancing selection increases with coloniality and migratory status. These patterns could be attributed to: (1) elevated transmission rates of pathogens in species that breed in dense aggregations, or (2) exposure to a more diverse fauna of pathogens and parasites in migratory species. Our study suggests that differences in social structure and basic ecological traits influence MHC diversity in natural vertebrate populations. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

  17. Status and distribution of migrating and breeding marine birds in north Lebanon

    International Nuclear Information System (INIS)

    Jarade, Gh.R.

    2017-01-01

    The study of marine birds in the northern part of Lebanon recorded 2681 individuals, distributed over 86 species. Among them 35 are foreshore species, 18 coastal, 6 maritime, 9 ducks, 6 herons, 9 various saltwater related species and 3 terrestrial. The highest density is shown by the yellow-legged Gull Larus michahellis and common blackheaded gull Chroicocephalus ridibundus. The globally vulnerable yelkouan shearwater Puffinus yelkouan, an endemic species to the Mediterranean, appears on the 9th rank in the classification of seabird species from the more to the least abundant, highlighting as such, beside other 6 globally near threatened species, the role that Lebanon can play in improving the conservation status of these species. Regarding the phenological status of species, 48 are passage migrant/winter visitors, 31 passage migrants, 5 winter visitors and 2 vagrant species. The surveys revealed that three coastal seabird species (Armenian gull Larus armenicus, slender-billed gull Chroicocephalus genei and sandwich tern Thalasseus sandvicensis) and one ubiquist species (Eurasian Golden Plover Pluvialis apricaria) are not rare as it was believed in previous papers but fairly common winter visitors. The study identified the yellow-legged gull breeding population to be 160 couples, and confirmed the second and third breeding records of the little ringed plover Charadrius dubius.(author)

  18. Population-level scaling of avian migration speed with body size and migration distance for powered fliers.

    Science.gov (United States)

    La Sorte, Frank A; Fink, Daniel; Hochachka, Wesley M; DeLong, John P; Kelling, Steve

    2013-08-01

    Optimal migration theory suggests specific scaling relationships between body size and migration speed for individual birds based on the minimization of time, energy, and risk. Here we test if the quantitative predictions originating from this theory can be detected when migration decisions are integrated across individuals. We estimated population-level migration trajectories and daily migration speeds for the combined period 2007-2011 using the eBird data set. We considered 102 North American bird species that use flapping or powered flight during migration. Many species, especially in eastern North America, had looped migration trajectories that traced a clockwise path with an eastward shift during autumn migration. Population-level migration speeds decelerated rapidly going into the breeding season, and accelerated more slowly during the transition to autumn migration. In accordance with time minimization predictions, spring migration speeds were faster than autumn migration speeds. In agreement with optimality predictions, migration speeds of powered flyers scaled negatively with body mass similarly during spring and autumn migration. Powered fliers with longer migration journeys also had faster migration speeds, a relationship that was more pronounced during spring migration. Our findings indicate that powered fliers employed a migration strategy that, when examined at the population level, was in compliance with optimality predictions. These results suggest that the integration of migration decisions across individuals does result in population-level patterns that agree with theoretical expectations developed at the individual level, indicating a role for optimal migration theory in describing the mechanisms underlying broadscale patterns of avian migration for species that use powered flight.

  19. 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.

  20. Immigration and Internal Migration "Flight" from US Metropolitan Areas: Toward a New Demographic Balkanisation.

    Science.gov (United States)

    Frey, William H.

    1995-01-01

    Examines migration dynamics for metropolitan areas that suggest immigration and internal migration processes are leading to a greater demographic balkanization--a spatial segmentation of the population by race, ethnicity, and socioeconomic status across metropolitan areas. A brief overview of migration at the state level is also provided. (GR)

  1. 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.

  2. Extreme migration and the individual quality spectrum

    NARCIS (Netherlands)

    Conklin, J.R.; Senner, N.R.; Battley, P.F.; Piersma, T.

    2017-01-01

    Costsof migration, in terms of time, energy, and mortality risk, have a strong theoretical and empirical foundation in thestudy of birds. We expect these costs to be most severe for extreme long-distance migratory landbirds, whose demandingannual routines (e.g. non-stop flights  8000 km and return

  3. Extreme migration and the individual quality spectrum

    NARCIS (Netherlands)

    Conklin, Jesse R.; Senner, Nathan R.; Battley, Philip F.; Piersma, Theunis

    Costs of migration, in terms of time, energy, and mortality risk, have a strong theoretical and empirical foundation in the study of birds. We expect these costs to be most severe for extreme long-distance migratory landbirds, whose demanding annual routines (e.g. non-stop flights > 8000 km and

  4. Spring migration of Ruffs Philomachus pugnax in Fryslan : estimates of staging duration using resighting data

    NARCIS (Netherlands)

    Verkuil, Yvonne I.; Wijmenga, Jan J.; Piersma, Theunis; Hooijmeijer, Jos C.E.W.

    2010-01-01

    Seasonal bird migration involves long flights, but most time is actually spent at intermediate staging areas. The duration of stay at these sites can be evaluated with mark recapture methods that employ day-to-day local encounters of individually marked birds. Estimates of staging duration are based

  5. Does intruder group size and orientation affect flight initiation distance in birds?

    Directory of Open Access Journals (Sweden)

    Geist, C.

    2005-06-01

    Full Text Available Wildlife managers use flight initiation distance (FID, the distance animals flee an approaching predator, to determine set back distances to minimize human impacts on wildlife. FID is typically estimated by a single person; this study examined the effects of intruder number and orientation on FID. Three different group size treatments (solitary person, two people side-by-side, two people one-behind-the-other were applied to Pied Currawongs (Strepera graculina and to Crimson Rosellas (Platycerus elegans. Rosellas flushed at significantly greater distances when approached by two people compared to a single person. This effect was not seen in currawongs. Intruder orientation did not influence the FID of either species. Results suggest that intruder number should be better integrated into estimates of set back distance to manage human visitation around sensitive species.

  6. The influence of weather on the flight altitude of nocturnal migrants in mid-latitudes

    NARCIS (Netherlands)

    Kemp, M.U.; Shamoun-Baranes, J.; Dokter, A.M.; van Loon, E.; Bouten, W.

    2013-01-01

    By altering its flight altitude, a bird can change the atmospheric conditions it experiences during migration. Although many factors may influence a bird's choice of altitude, wind is generally accepted as being the most influential. However, the influence of wind is not clearly understood,

  7. 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.

  8. 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).

  9. Do the ticks of birds at an important migratory hotspot reflect the seasonal dynamics of Ixodes ricinus at the migration initiation site? A case study in the Danube Delta.

    Science.gov (United States)

    Sándor, Attila D; Mărcuţan, Daniel I; D'Amico, Gianluca; Gherman, Călin M; Dumitrache, Mirabela O; Mihalca, Andrei D

    2014-01-01

    Migratory birds play important roles as distributors of ticks within and between continents. In the Old World, the most important migratory route of birds links Asia, Europe and Africa. During their migration, birds use various stopover sites, where they feed and rest and where ticks may attach or detach, creating new natural foci for vector-borne diseases. Danube Delta is one of the most important migration hotspots and so far no studies were focused on ticks of migratory birds herein. The aim of the present study was to assess the species diversity and seasonal dynamics of ticks parasitizing migratory birds in Danube Delta Biosphere Reserve. Migratory birds were trapped on Grindul Lupilor (44°41'N; 28°56'E) using mist nets during 4 migratory seasons (2 spring and 2 autumn) in 2011 and 2012. From each bird, all the ticks were collected and identified based on morphological features. Epidemiological parameters (prevalence, mean abundance, mean intensity) were calculated and all data were analysed statistically based on the season (spring and autumn), regional status of birds (migrants and breeding) and foraging behaviour (ground feeders, reed-bed feeders, foliage feeders). A total of 1434 birds (46 species) were captured. Ticks were found on 94 birds (10 species). Significantly more migratory birds hosted ticks, compared to resident birds. The 400 collected ticks belonged to four species: Ixodes ricinus (92.25%), I. arboricola (6.25%), I. redikorzevi (1.00%) and Haemaphysalis punctata (0.50%). A higher prevalence was found for I. ricinus in spring, with higher prevalence of nymphs in this season, while larvae occurred with the same prevalence in both seasons. Larval intensity was higher during spring and nymphs were more abundant during autumn. The seasonal differences in our study may be related not to the local seasonal dynamics of ticks, but on the seasonal dynamics at the site of migration initiation.

  10. Do the ticks of birds at an important migratory hotspot reflect the seasonal dynamics of Ixodes ricinus at the migration initiation site? A case study in the Danube Delta.

    Directory of Open Access Journals (Sweden)

    Attila D Sándor

    Full Text Available Migratory birds play important roles as distributors of ticks within and between continents. In the Old World, the most important migratory route of birds links Asia, Europe and Africa. During their migration, birds use various stopover sites, where they feed and rest and where ticks may attach or detach, creating new natural foci for vector-borne diseases. Danube Delta is one of the most important migration hotspots and so far no studies were focused on ticks of migratory birds herein. The aim of the present study was to assess the species diversity and seasonal dynamics of ticks parasitizing migratory birds in Danube Delta Biosphere Reserve. Migratory birds were trapped on Grindul Lupilor (44°41'N; 28°56'E using mist nets during 4 migratory seasons (2 spring and 2 autumn in 2011 and 2012. From each bird, all the ticks were collected and identified based on morphological features. Epidemiological parameters (prevalence, mean abundance, mean intensity were calculated and all data were analysed statistically based on the season (spring and autumn, regional status of birds (migrants and breeding and foraging behaviour (ground feeders, reed-bed feeders, foliage feeders. A total of 1434 birds (46 species were captured. Ticks were found on 94 birds (10 species. Significantly more migratory birds hosted ticks, compared to resident birds. The 400 collected ticks belonged to four species: Ixodes ricinus (92.25%, I. arboricola (6.25%, I. redikorzevi (1.00% and Haemaphysalis punctata (0.50%. A higher prevalence was found for I. ricinus in spring, with higher prevalence of nymphs in this season, while larvae occurred with the same prevalence in both seasons. Larval intensity was higher during spring and nymphs were more abundant during autumn. The seasonal differences in our study may be related not to the local seasonal dynamics of ticks, but on the seasonal dynamics at the site of migration initiation.

  11. 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.

  12. 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

  13. 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.

  14. 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....

  15. Migratory Birds. Issue Pac.

    Science.gov (United States)

    Fish and Wildlife Service (Dept. of Interior), Washington, DC.

    The materials in this educational packet are designed for use with students in grades 4 through 7. They consist of an overview, teaching guides and student data sheets for three activities, and a poster. The overview discusses why, how, where, and when birds migrate as well as problems birds encounter while migrating; the importance of research…

  16. 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.

  17. On the size and flight diversity of giant pterosaurs, the use of birds as pterosaur analogues and comments on pterosaur flightlessness.

    Directory of Open Access Journals (Sweden)

    Mark P Witton

    Full Text Available The size and flight mechanics of giant pterosaurs have received considerable research interest for the last century but are confused by conflicting interpretations of pterosaur biology and flight capabilities. Avian biomechanical parameters have often been applied to pterosaurs in such research but, due to considerable differences in avian and pterosaur anatomy, have lead to systematic errors interpreting pterosaur flight mechanics. Such assumptions have lead to assertions that giant pterosaurs were extremely lightweight to facilitate flight or, if more realistic masses are assumed, were flightless. Reappraisal of the proportions, scaling and morphology of giant pterosaur fossils suggests that bird and pterosaur wing structure, gross anatomy and launch kinematics are too different to be considered mechanically interchangeable. Conclusions assuming such interchangeability--including those indicating that giant pterosaurs were flightless--are found to be based on inaccurate and poorly supported assumptions of structural scaling and launch kinematics. Pterosaur bone strength and flap-gliding performance demonstrate that giant pterosaur anatomy was capable of generating sufficient lift and thrust for powered flight as well as resisting flight loading stresses. The retention of flight characteristics across giant pterosaur skeletons and their considerable robustness compared to similarly-massed terrestrial animals suggest that giant pterosaurs were not flightless. Moreover, the term 'giant pterosaur' includes at least two radically different forms with very distinct palaeoecological signatures and, accordingly, all but the most basic sweeping conclusions about giant pterosaur flight should be treated with caution. Reappraisal of giant pterosaur material also reveals that the size of the largest pterosaurs, previously suggested to have wingspans up to 13 m and masses up to 544 kg, have been overestimated. Scaling of fragmentary giant pterosaur remains

  18. 75 FR 52873 - Migratory Bird Hunting; Final Frameworks for Early-Season Migratory Bird Hunting Regulations

    Science.gov (United States)

    2010-08-30

    ... resources including migratory birds and their habitats. Large-scale efforts to influence bird migration and... timing and speed of bird migrations. It is possible that re-distribution of birds at smaller scales could...-0040; 91200-1231-9BPP-L2] RIN 1018-AX06 Migratory Bird Hunting; Final Frameworks for Early-Season...

  19. Continental scale analysis of bird migration timing: influences of climate and life history traits-a generalized mixture model clustering and discriminant approach.

    Science.gov (United States)

    Chambers, Lynda E; Beaumont, Linda J; Hudson, Irene L

    2014-08-01

    There is substantial evidence of climate-related shifts to the timing of avian migration. Although spring arrival has generally advanced, variable species responses and geographical biases in data collection make it difficult to generalise patterns. We advance previous studies by using novel multivariate statistical techniques to explore complex relationships between phenological trends, climate indices and species traits. Using 145 datasets for 52 bird species, we assess trends in first arrival date (FAD), last departure date (LDD) and timing of peak abundance at multiple Australian locations. Strong seasonal patterns were found, i.e. spring phenological events were more likely to significantly advance, while significant advances and delays occurred in other seasons. However, across all significant trends, the magnitude of delays exceeded that of advances, particularly for FAD (+22.3 and -9.6 days/decade, respectively). Geographic variations were found, with greater advances in FAD and LDD, in south-eastern Australia than in the north and west. We identified four species clusters that differed with respect to species traits and climate drivers. Species within bird clusters responded in similar ways to local climate variables, particularly the number of raindays and rainfall. The strength of phenological trends was more strongly related to local climate variables than to broad-scale drivers (Southern Oscillation Index), highlighting the importance of precipitation as a driver of movement in Australian birds.

  20. Trade-off between migration and reproduction : does a high workload affect body condition and reproductive state?

    NARCIS (Netherlands)

    Schmidt-Wellenburg, Carola A.; Visser, G. Henk; Biebach, Brigitte; Delhey, Kaspar; Oltrogge, Martina; Wittenzellner, Andrea; Biebach, Herbert; Kempenaers, Bart

    2008-01-01

    Migratory birds have to invest much energy into flight to reach their summer and winter quarters. Many studies have shown how migration affects body physiology, including the accumulation of energy stores and the reduction of nonessential organs. In spring, the costs of migration may trade-off with

  1. Using Autumn Hawk Watch to track raptor migration and to monitor populations of North American birds of prey

    Science.gov (United States)

    Kyle McCarty; Keith L. Bildstein

    2005-01-01

    Raptors are secretive, area-sensitive predators whose populations can be logistically difficult and financially prohibitive to monitor. Many North American populations of raptors are migratory however, and on migration raptors are frequently counted at traditional migration watchsites. Experiences at Hawk Mountain Sanctuary (HMS) and elsewhere suggest that long-term...

  2. 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

    -specific information about the incorporation of deuterium into peptides and proteins in solution. Using a unique set of peptides with their carboxyl-terminal half labeled with deuterium we have shown unambiguously that hydrogen (1H/2H) scrambling is such a dominating factor during low energy collisional activation...... 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...

  3. Autumn and spring migration of the Reed Warbler Acrocephalus ...

    African Journals Online (AJOL)

    At three stations more birds per day were caught in spring than in autumn. Deviating geographical conditions induced high capturing numbers at the Red Sea coast, particularly in autumn. Differences between spring and autumn may indicate loop migration and/or seasonally differing flight or resting strategies. Wing-length ...

  4. Mathematical model for bird flu disease transmission with no bird ...

    African Journals Online (AJOL)

    In this paper a mathematical model for the transmission dynamics of bird flu among birds and humans is presented. The model assumes that there is no migration of birds in the susceptible bird population immediately the disease starts. The model formulated is analyzed using dynamical systems theory . The analysis of the ...

  5. mathematical model for bird flu disease transmission with no bird ...

    African Journals Online (AJOL)

    Admin

    In this paper a mathematical model for the transmission dynamics of bird flu among birds and humans is presented. The model assumes that there is no migration of birds in the susceptible bird population immediately the disease starts. The model formulated is analyzed using dynamical systems theory. The analysis of the ...

  6. Use of animal and plant phenology for flight safety

    Science.gov (United States)

    Hild, J.

    1980-09-01

    The relationship between the appearance of small soil animals, number of birds and the season makes it possible to judge flight safety risks. The phenological phase of special plant species also controls the appearance of birds, for particular birds prefer particular states of vegetation, e.g. in pastured areas. This may suggest the possibilities for flight safety in the airfields and their vicinity. During low and high level flights of aircraft it has been necessary to forecast the beginning and course of migration. Beginning of migration is a function of fat deposit in the bird's body which in turn is a function of food uptake. Weather situations and single meteorological parameters influence the course of migration. By observing bird migration by radar and by combining radar data with weather data it has been possible to publish not only medium and long-scale forecasts but also actual warnings. Modern radar technique rendered the observation more difficult but this problem can be solved by introducing new methods.

  7. 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.

  8. Optimal moult strategies in migratory birds.

    Science.gov (United States)

    Barta, Zoltán; McNamara, John M; Houston, Alasdair I; Weber, Thomas P; Hedenström, Anders; Feró, Orsolya

    2008-01-27

    Avian migration, which involves billions of birds flying vast distances, is known to influence all aspects of avian life. Here we investigate how birds fit moult into an annual cycle determined by the need to migrate. Large variation exists in moulting patterns in relation to migration: for instance, moult can occur after breeding in the summer or after arrival in the wintering quarters. Here we use an optimal annual routine model to investigate why this variation exists. The modelled bird's decisions depend on the time of year, its energy reserves, breeding status, experience, flight feather quality and location. Our results suggest that the temporal and spatial variations in food are an important influence on a migratory bird's annual cycle. Summer moult occurs when food has a high peak on the breeding site in the summer, but it is less seasonal elsewhere. Winter moult occurs if there is a short period of high food availability in summer and a strong winter peak at different locations (i.e. the food is very seasonal but in opposite phase on these areas). This finding might explain why only long-distance migrants have a winter moult.

  9. Identification of Rickettsia africae and Wolbachia sp. in Ceratophyllus garei fleas from Passerine birds migrated from Africa.

    Science.gov (United States)

    Sekeyová, Zuzana; Mediannikov, Oleg; Roux, Véronique; Subramanian, Geetha; Spitalská, Eva; Kristofík, Jano; Darolová, Alžbeta; Raoult, Didier

    2012-07-01

    The aim of the study was to reveal new aspects of the role of flea vector taken from migratory birds by screening of specimens with molecular biological methods. A field study was done in fishponds in Slovakia. Actually, 47 fleas were collected from reed warblers (Acrocephalus scirpaceus) and their nests. DNA was extracted and analyzed for representatives of the orders Rickettsiales. A rickettsia that shares 99.7% of identity by gltA gene with Rickettsia africae was identified in Ceratophyllus garei collected from A. scirpaceus. Moreover, two Wolbachia sp. were also detected in fleas. This is the first record of R. africae and Wolbachia sp. identified so far in Central Europe in fleas collected from migratory bird returning from Africa. This molecular study extends the geographic range and vector spectrum of arthropod-borne agents.

  10. How do diurnal long-distance migrants select flight altitude in relation to wind?

    OpenAIRE

    María Mateos-Rodríguez; Felix Liechti

    2012-01-01

    To save energy and time, migratory birds are expected to select time periods and flight altitudes with favorable wind conditions. In spring 2006, we studied diurnal migration using tracking radar at the Strait of Messina. A total of 1530 radar tracks were analyzed with respect to flight altitude and wind conditions. The tracks included Honey Buzzards, Marsh, Montagu's, and Pallid Harriers, Black Kites, falcons, swallows, swifts, and herons. Maximum flight altitude recorded was 2495 m above gr...

  11. Long flights do not influence immune responses of a long-distance migrant bird : a wind-tunnel experiment

    NARCIS (Netherlands)

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

    2007-01-01

    Heavy physical work can result in physiological stress and suppressed immune function. Accordingly, long-distance migrant birds that fly for thousands of km within days can be expected to show immunosuppression, and hence be more vulnerable to infections en route. The red knot Calidris canutus

  12. 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.

  13. Improving The Accuracy Of Selection Of Bird Radar Echoes Against A Background Of Atomized Clouds And Atmospheric Inhomogeneities

    Directory of Open Access Journals (Sweden)

    Dinevich Leonid

    2015-12-01

    Full Text Available The algorithm for bird radar echo selection was developed in Israel and has been successfully used for many years to monitor birds in periods of massive intercontinental migration in order to ensure flight safety in civil and military aviation. However, it has been found that under certain meteorological conditions the bird echo selection algorithm does not filter out false signals formed by atomized clouds and atmospheric inhomogeneities. Although the algorithm is designed to identify and sift false signals, some useful echoes from smaller birds are erroneously sifted as well.

  14. 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.

  15. 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.

  16. 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

  17. 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

  18. 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%)

  19. Flight performance and feather quality: paying the price of overlapping moult and breeding in a tropical highland bird.

    Directory of Open Access Journals (Sweden)

    Maria Angela Echeverry-Galvis

    Full Text Available A temporal separation of energetically costly life history events like reproduction and maintenance of the integumentary system is thought to be promoted by selection to avoid trade-offs and maximize fitness. It has therefore remained somewhat of a paradox that certain vertebrate species can undergo both events simultaneously. Identifying potential costs of overlapping two demanding life history stages will further our understanding of the selection pressures that shape the temporal regulation of life history events in vertebrates. We studied free-living tropical Slaty brush-finches (Atlapetes schistaceus, in which individuals spontaneously overlap reproduction and moult or undergo both events in separation. To assess possible costs of such an overlap we quantified feather quality and flight performance of individuals in different states. We determined individual's life history state by measuring gonad size and scoring moult stage, and collected a newly grown 7(th primary wing feather for later analysis of feather quality. Finally, we quantified flight performance for each individual in the wild. Overlapping individuals produced lighter and shorter wing feathers than individuals just moulting, with females decreasing feather quality more strongly during the overlap than males. Moreover, overlapping individuals had a reduced flight speed during escape flights, while their foraging flight speed was unaffected. Despite overlappers being larger and having a smaller wing area, their lower body mass resulted in a similar wing load as in breeders or moulters. Individuals measured repeatedly in different states also showed significant decreases in feather quality and escape flight speed during the overlap. Reduced escape flight speed may represent a major consequence of the overlap by increasing predation risk. Our data document costs to undergoing two life history stages simultaneously, which likely arise from energetic trade-offs. Impairments in

  20. 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

  1. 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.

  2. [Speed of migratory movements in birds as adaptive behaviour].

    Science.gov (United States)

    Paevskiĭ, V A

    2012-01-01

    Migration speed of 115 bird species from 35 families of 14 orders was analyzed. The data were collected from published sources based on ringing recoveries. It was found that average speed varies between 10 and 880 km/day, and the maximum speed varies between 30 and 1392 km/day, but in the majority of species the average speed values are in the range of 20-100, and the maximum speed values are in the range of 40-360 km/day There is significant positive correlation between the average and maximum speed. The ratio between maximum and average speed in different species varies significantly, and overall for all birds is 4:1. On average, shorebirds migrate twice as rapidly as passerines, and average speed of the raptors is rather higher than in shorebirds. The species from Turdidae family migrate significantly faster than the species from Fringillidae family, and the latter migrate faster than tits. No significant differences in migration speed were found between the species from Sylviidae and Turdidae families, as well as between Sylviidae and Motacillidae. Significant negative correlation was found between the body mass and average migration speed in the shorebirds, but no relationship between these parameters was found in the passerines. In many bird species, adult birds migrate significantly faster than juveniles, and in some species no difference in speed was found between males and females. In the passerines, the average migration speed is significantly higher among long-distance early-departing nocturnal migrants as compared with the short-distance late-departing diurnal ones. The spring migration speed was much higher than autumn speed, but in some species only. The beha-vior of migrants at flight and at stopovers is governed by a complex interaction between their species-specific foraging features, weather conditions, and habitat.

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

    Science.gov (United States)

    Forest dwelling neotropical migratory birds require intact forested stopovers during migration. The number of paths that pass through a HUC highlight that huc's importance in the migratory system. I modeled migratory flights based on flight distance and direction to examine how nightly flights link stopovers into flyways. The resulting maps highlight portions of the landscape that are important for the continued success of migratory birds. Areas where many different migration scenarios overlap are particularly important, as these areas will support a diverse collection of migratory strategies and populations. More information about these resources, including the variables used in this study, may be found here: https://edg.epa.gov/data/Public/ORD/NERL/ReVA/ReVA_Data.zip.

  4. Number of Migration Scenarios Passing through each HUC

    Science.gov (United States)

    Forest dwelling neotropical migratory birds require intact forested stopovers during migration. The number of paths that pass through a HUC highlight that huc's importance in the migratory system. I modeled migratory flights based on flight distance and direction to examine how nightly flights link stopovers into flyways. The resulting maps highlight portions of the landscape that are important for the continued success of migratory birds. Areas where many different migration scenarios overlap are particularly important, as these areas will support a diverse collection of migratory strategies and populations. More information about these resources, including the variables used in this study, may be found here: https://edg.epa.gov/data/Public/ORD/NERL/ReVA/ReVA_Data.zip.

  5. Understanding the migratory orientation program of birds

    DEFF Research Database (Denmark)

    Thorup, Kasper; Holland, Richard A.; Tøttrup, Anders P.

    2010-01-01

    orient during migration. Despite the difficulties associated with following free-flying birds over long distances, a number of possibilities currently exist for tracking the long distance, sometimes even globe-spanning, journeys undertaken by migrating birds. Birds fitted with radio transmitters can......For many years, orientation in migratory birds has primarily been studied in the laboratory. Although a laboratory-based setting enables greater control over environmental cues, the laboratory-based findings must be confirmed in the wild in free-flying birds to be able to fully understand how birds...... system that enables experienced birds to navigate and guide inexperienced, young birds to their species-specific winter grounds...

  6. 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

  7. 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.

  8. 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.

  9. 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.

  10. Birds of Prey of Wisconsin.

    Science.gov (United States)

    Hamerstrom, Frances

    This copiously illustrated document is designed to be a field quide to birds of prey that are common to Wisconsin, as well as to some that enter the state occasionally. An introduction discusses birds of prey with regard to migration patterns, the relationship between common names and the attitudes of people toward certain birds, and natural signs…

  11. Alternate non-stop migration strategies of pied flycatchers to cross the Sahara desert

    NARCIS (Netherlands)

    Ouwehand, Janne; Both, Christiaan

    Each year more than two billion songbirds cross the Sahara, but how they perform this formidable task is largely unknown. Using geolocation tracks from 27 pied flycatchers, a nocturnally migrating passerine, we show that most birds made diurnal flights in both autumn and spring. These diurnal

  12. 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

  13. 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

  14. Move that fatty acid: fuel selection and transport in migratory birds and bats.

    Science.gov (United States)

    Guglielmo, Christopher G

    2010-09-01

    The metaphor of marathon running is inadequate to fully capture the magnitude of long-distance migratory flight of birds. In some respects a journey to the moon seems more appropriate. Birds have no access to supplementary water or nutrition during a multi-day flight, and they must carefully budget their body fat and protein stores to provide both fuel and life support. Fatty acid transport is crucial to successful non-stop migratory flight in birds. Although fat is the most energy-dense metabolic fuel, the insolubility of its component fatty acids makes them difficult to transport to working muscles fast enough to support the highly aerobic exercise required to fly. Recent evidence indicates that migratory birds compensate for this by expressing large amounts of fatty acid transport proteins on the membranes of the muscles (FAT/CD36 and FABPpm) and in the cytosol (H-FABP). Through endogenous mechanisms and/or diet, migratory birds may alter the fatty acid composition of the fat stores and muscle membranes to improve endurance during flight. Fatty acid chain length, degree of unsaturation, and placement of double bonds can affect the rate of mobilization of fatty acids from adipose tissue, utilization of fatty acids by muscles, and whole-animal performance. However, there is great uncertainty about how important fatty acid composition is to the success of migration or whether particular types of fatty acids (e.g., omega-3 or omega-6) are most beneficial. Migratory bats provide an interesting example of evolutionary convergence with birds, which may provide evidence for the generality of the bird model to the evolution of migration by flight in vertebrates. Yet only recently have attempts been made to study bat migration physiology. Many aspects of their fuel metabolism are predicted to be more similar to those of migrant birds than to those of non-flying mammals. Bats may be distinct from most birds in their potential to conserve energy by using torpor between

  15. Priority areas for surveillance and prevention of avian influenza during the water-bird migration season in Pakistan

    Directory of Open Access Journals (Sweden)

    Tariq Abbas

    2011-11-01

    Full Text Available Avian influenza viruses may be introduced into domestic poultry through migratory wild birds, particularly from Pakistan, which is situated across the migratory Indus flyway and holds more than 225 wetlands. To answer the question which areas should be given priority in surveillance and prevention with respect to notifiable avian influenza during the migratory season, a subset of Asian waterbird census data was reviewed. The dataset contains 535 local sites and available counts of waterbirds reported from 1987 to 2007. However, as the majority of the sites are not counted regularly gaps in data matrix appeared. The coordinates of 270 known sites completely fitted the administrative boundaries of the country. These coordinates were geo-processed with polygons of water-bodies and a raster map of predicted poultry density. Pixels representing the estimated number of poultry per km2 were found within a 3 to 9 km range of the census sites (or water-bodies in their proximity. The coordinates were also used to map the maximum reported counts of waterbirds and local clusters of under-sampled sites. A retrospective case-series analysis of previous outbreaks (2006-2008 of influenza A virus, subtype H5N1 was performed, which revealed that 64% of outbreaks, reported to Office International des Epizooties, the World Organization for Animal Health, occurred during the migratory period. This paper highlights the potential use and limitations of the Asian waterbirds census data in the context of avian influenza. The proposed methodology may be used to prioritize districts for surveillance and economize prevention measures provided better data are generated in future.

  16. How do energy stores and changes in these affect departure decisions by migratory birds? A critical view on stopover ecology studies and some future perspectives.

    Science.gov (United States)

    Schmaljohann, Heiko; Eikenaar, Cas

    2017-07-01

    In birds, accumulating energy is far slower than spending energy during flight. During migration, birds spend, therefore, most of the time at stopover refueling energy used during the previous flight. This elucidates why current energy stores and actual rate of accumulating energy are likely crucial factors influencing bird's decision when to resume migration in addition to other intrinsic (sex, age) and extrinsic (predation, weather) factors modulating the decision within the innate migration program. After first summarizing how energy stores and stopover durations are generally determined, we critically review that high-energy stores and low rates of accumulating energy were significantly related to high departure probabilities in several bird groups. There are, however, also many studies showing no effect at all. Recent radio-tracking studies highlighted that migrants leave a site either to resume migration or to search for a better stopover location, so-called "landscape movements". Erroneously treating such movements as departures increases the likelihood of type II errors which might mistakenly suggest no effect of either trait on departure. Furthermore, we propose that energy loss during the previous migratory flight in relation to bird's current energy stores and migration strategy significantly affects its urge to refuel and hence its departure decision.

  17. Flight responses by a migratory soaring raptor to changing meteorological conditions.

    Science.gov (United States)

    Lanzone, Michael J; Miller, Tricia A; Turk, Philip; Brandes, David; Halverson, Casey; Maisonneuve, Charles; Tremblay, Junior; Cooper, Jeff; O'Malley, Kieran; Brooks, Robert P; Katzner, Todd

    2012-10-23

    Soaring birds that undertake long-distance migration should develop strategies to minimize the energetic costs of endurance flight. This is relevant because condition upon completion of migration has direct consequences for fecundity, fitness and thus, demography. Therefore, strong evolutionary pressures are expected for energy minimization tactics linked to weather and topography. Importantly, the minute-by-minute mechanisms birds use to subsidize migration in variable weather are largely unknown, in large part because of the technological limitations in studying detailed long-distance bird flight. Here, we show golden eagle (Aquila chrysaetos) migratory response to changing meteorological conditions as monitored by high-resolution telemetry. In contrast to expectations, responses to meteorological variability were stereotyped across the 10 individuals studied. Eagles reacted to increased wind speed by using more orographic lift and less thermal lift. Concomitantly, as use of thermals decreased, variation in flight speed and altitude also decreased. These results demonstrate how soaring migrant birds can minimize energetic expenditures, they show the context for avian decisions and choices of specific instantaneous flight mechanisms and they have important implications for design of bird-friendly wind energy.

  18. 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

  19. Wind assistance: A requirement for migration of shorebirds?

    Science.gov (United States)

    Butler, Robert W.; Williams, Tony D.; Warnock, Nils; Bishop, Mary Anne

    1997-01-01

    We investigated the importance of wind-assisted flight for northward (spring) migration by Western Sandpipers (Calidris mauri) along the Pacific Coast of North America. Using current models of energy costs of flight and recent data on the phenology of migration, we estimated the energy (fat) requirements for migration in calm winds and with wind-assisted flight for different rates of fat deposition: (1) a variable rate, assuming that birds deposit the minimum amount of fat required to reach the next stopover site; (2) a constant maximum rate of 1.0 g/day; and (3) a lower constant rate of 0.4 g/day. We tested these models by comparing conservative estimates of predicted body mass along the migration route with empirical data on body mass of Western Sandpipers at different stopover sites and upon arrival at the breeding grounds. In calm conditions, birds would have to deposit unrealistically high amounts of fat (up to 330% of observed values) to maintain body mass above absolute lean mass values. Fat-deposition rates of 1.0 g/day and 0.4 g/day, in calm conditions, resulted in a steady decline in body mass along the migration route, with predicted body masses on arrival in Alaska of only 60% (13.6 g) and 26% (5.9 g) of average lean mass (22.7 g). Conversely, birds migrating with wind assistance would be able to complete migration with fat-deposition rates as low as 0.4 g/day, similar to values reported for this size bird from field studies. Our results extend the conclusion of the importance of winds for large, long-distance migrants to a small, short-distance migrant. We suggest that the migratory decisions of birds are more strongly influenced by the frequency and duration of winds aloft, i.e. by events during the flight phase, than by events during the stopover phase of migration, such as fat-deposition rate, that have been the focus of much recent migration theory.

  20. Influence of atmospheric properties on detection of wood-warbler nocturnal flight calls.

    Science.gov (United States)

    Horton, Kyle G; Stepanian, Phillip M; Wainwright, Charlotte E; Tegeler, Amy K

    2015-10-01

    Avian migration monitoring can take on many forms; however, monitoring active nocturnal migration of land birds is limited to a few techniques. Avian nocturnal flight calls are currently the only method for describing migrant composition at the species level. However, as this method develops, more information is needed to understand the sources of variation in call detection. Additionally, few studies examine how detection probabilities differ under varying atmospheric conditions. We use nocturnal flight call recordings from captive individuals to explore the dependence of flight call detection on atmospheric temperature and humidity. Height or distance from origin had the largest influence on call detection, while temperature and humidity also influenced detectability at higher altitudes. Because flight call detection varies with both atmospheric conditions and flight height, improved monitoring across time and space will require correction for these factors to generate standardized metrics of songbird migration.

  1. Influence of atmospheric properties on detection of wood-warbler nocturnal flight calls

    Science.gov (United States)

    Horton, Kyle G.; Stepanian, Phillip M.; Wainwright, Charlotte E.; Tegeler, Amy K.

    2015-10-01

    Avian migration monitoring can take on many forms; however, monitoring active nocturnal migration of land birds is limited to a few techniques. Avian nocturnal flight calls are currently the only method for describing migrant composition at the species level. However, as this method develops, more information is needed to understand the sources of variation in call detection. Additionally, few studies examine how detection probabilities differ under varying atmospheric conditions. We use nocturnal flight call recordings from captive individuals to explore the dependence of flight call detection on atmospheric temperature and humidity. Height or distance from origin had the largest influence on call detection, while temperature and humidity also influenced detectability at higher altitudes. Because flight call detection varies with both atmospheric conditions and flight height, improved monitoring across time and space will require correction for these factors to generate standardized metrics of songbird migration.

  2. Energy metabolism during endurance flight and the post-flight recovery phase.

    Science.gov (United States)

    Jenni-Eiermann, Susanne

    2017-07-01

    Migrating birds are known to fly non-stop for thousands of kilometres without food or water intake and at a high metabolic rate thereby relying on energy stores which were built up preceding a flight bout. Hence, from a physiological point of view the metabolism of a migrant has to switch between an active fasting phase during flight and a fuelling phase during stopover. To meet the energetic and water requirements of endurance flight, migratory birds have to store an optimal fuel composition and they have to be able to quickly mobilize and deliver sufficient energy to the working flight muscles. After flight, birds have to recover from a strenuous exercise and sleeplessness, but, at the same time, they have to be alert to escape from predators and to prepare the next flight bout. In this overview, metabolic adaptations of free-ranging migrants to both phases will be presented and compared with results from windtunnel studies. The questions whether migratory strategy (long distance versus short distance) and diet composition influence the metabolic pathways will be discussed.

  3. The flight apparatus of migratory and sedentary individuals of a partially migratory songbird species.

    Science.gov (United States)

    Fudickar, Adam M; Partecke, Jesko

    2012-01-01

    Variations in the geometry of the external flight apparatus of birds are beneficial for different behaviors. Long-distance flight is less costly with more pointed wings and shorter tails; however these traits decrease maneuverability at low speeds. Selection has led to interspecific differences in these and other flight apparatuses in relation to migration distance. If these principles are general, how are the external flight apparatus within a partially migratory bird species shaped in which individuals either migrate or stay at their breeding grounds? We resolved this question by comparing the wing pointedness and tail length (relative to wing length) of migrant and resident European blackbirds (Turdus merula) breeding in the same population. We predicted that migrant blackbirds would have more pointed wings and shorter tails than residents. Contrary to our predictions, there were no differences between migrants and residents in either measure. Our results indicate that morphological differences between migrants and residents in this partially migratory population may be constrained.

  4. 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)

  5. Light oiling of feathers increases flight energy expenditure in a migratory shorebird.

    Science.gov (United States)

    Maggini, Ivan; Kennedy, Lisa V; Macmillan, Alexander; Elliott, Kyle H; Dean, Karen; Guglielmo, Christopher G

    2017-07-01

    Flying birds depend on their feathers to undertake most activities, and maintain them in peak condition through periodic molt and frequent preening. Even small exposures to crude oil reduce the integrity of feathers, and could impair flight performance. We trained wild western sandpipers ( Calidris mauri ) to perform endurance flights in a wind tunnel, and used magnetic resonance body composition analysis to measure energy expenditure after birds were exposed to weathered MC252 crude oil from the Deepwater Horizon oil spill. The cost of transport was 0.26±0.04 kJ km -1 in controls, and increased by 22% when the trailing edges of the wing and tail were oiled (flight control, and only half of moderately oiled birds completed the flight test. We then flew birds at a range of speeds to estimate basic kinematic parameters. At low speeds, light and moderately oiled birds had larger wingbeat amplitudes than controls, while moderately oiled birds showed greater wingbeat frequencies across all speeds, and a shift in optimal flight speed towards higher wind speeds. We suggest these changes reflect poorer lift production and increased drag on the wings and body. Oiling will increase the difficulty and energy costs of locomotion for daily and seasonal activities such as foraging, predator evasion, territory defense, courtship, chick provisioning, commuting and long-distance migration. These sub-lethal effects must be considered in oil spill impact assessments. © 2017. Published by The Company of Biologists Ltd.

  6. 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

  7. Pallid Harrier Circus macrourus bird hunting behaviour and capture ...

    African Journals Online (AJOL)

    Detailed observations were made of Pallid Harrier Circus macrourus behaviour when hunting birds, the bird prey species and bird capture success in northern Cameroon. Four hunting strategies are described to capture birds: fast contour flight, overt approach with rapid acceleration, covert ambush, and stoop from flight.

  8. Hippocampal neurogenesis and volume in migrating and wintering semipalmated sandpipers (Calidris pusilla).

    Science.gov (United States)

    de Morais Magalhães, Nara Gyzely; Guerreiro Diniz, Cristovam; Guerreiro Diniz, Daniel; Pereira Henrique, Ediely; Corrêa Pereira, Patrick Douglas; Matos Moraes, Isis Ananda; Damasceno de Melo, Mauro André; Sherry, David Francis; Wanderley Picanço Diniz, Cristovam

    2017-01-01

    Long distance migratory birds find their way by sensing and integrating information from a large number of cues in their environment. These cues are essential to navigate over thousands of kilometers and reach the same breeding, stopover, and wintering sites every year. The semipalmated sandpiper (Calidris pusilla) is a long-distance migrant that breeds in the arctic tundra of Canada and Alaska and winters on the northeast coast of South America. Its fall migration includes a 5,300-kilometer nonstop flight over the Atlantic Ocean. The avian hippocampus has been proposed to play a central role in the integration of multisensory spatial information for navigation. Hippocampal neurogenesis may contribute to hippocampal function and a variety of factors including cognitive activity, exercise, enrichment, diet and stress influence neurogenesis in the hippocampus. We quantified hippocampal neurogenesis and volume in adult migrating and wintering semipalmated sandpipers using stereological counts of doublecortin (DCX) immunolabeled immature neurons. We found that birds captured in the coastal region of Bragança, Brazil during the wintering period had more DCX positive neurons and larger volume in the hippocampus than individuals captured in the Bay of Fundy, Canada during fall migration. We also estimate the number of NeuN immunolabeled cells in migrating and wintering birds and found no significant differences between them. These findings suggest that, at this time window, neurogenesis just replaced neurons that might be lost during the transatlantic flight. Our findings also show that in active fall migrating birds, a lower level of adult hippocampal neurogenesis is associated with a smaller hippocampal formation. High levels of adult hippocampal neurogenesis and a larger hippocampal formation found in wintering birds may be late occurring effects of long distance migratory flight or the result of conditions the birds experienced while wintering.

  9. Hippocampal neurogenesis and volume in migrating and wintering semipalmated sandpipers (Calidris pusilla.

    Directory of Open Access Journals (Sweden)

    Nara Gyzely de Morais Magalhães

    Full Text Available Long distance migratory birds find their way by sensing and integrating information from a large number of cues in their environment. These cues are essential to navigate over thousands of kilometers and reach the same breeding, stopover, and wintering sites every year. The semipalmated sandpiper (Calidris pusilla is a long-distance migrant that breeds in the arctic tundra of Canada and Alaska and winters on the northeast coast of South America. Its fall migration includes a 5,300-kilometer nonstop flight over the Atlantic Ocean. The avian hippocampus has been proposed to play a central role in the integration of multisensory spatial information for navigation. Hippocampal neurogenesis may contribute to hippocampal function and a variety of factors including cognitive activity, exercise, enrichment, diet and stress influence neurogenesis in the hippocampus. We quantified hippocampal neurogenesis and volume in adult migrating and wintering semipalmated sandpipers using stereological counts of doublecortin (DCX immunolabeled immature neurons. We found that birds captured in the coastal region of Bragança, Brazil during the wintering period had more DCX positive neurons and larger volume in the hippocampus than individuals captured in the Bay of Fundy, Canada during fall migration. We also estimate the number of NeuN immunolabeled cells in migrating and wintering birds and found no significant differences between them. These findings suggest that, at this time window, neurogenesis just replaced neurons that might be lost during the transatlantic flight. Our findings also show that in active fall migrating birds, a lower level of adult hippocampal neurogenesis is associated with a smaller hippocampal formation. High levels of adult hippocampal neurogenesis and a larger hippocampal formation found in wintering birds may be late occurring effects of long distance migratory flight or the result of conditions the birds experienced while wintering.

  10. Low intensity blood parasite infections do not reduce the aerobic performance of migratory birds

    Science.gov (United States)

    Dimitrov, Dimitar; Ivanova, Karina; Zehtindjiev, Pavel

    2018-01-01

    Blood parasites (Haemosporidia) are thought to impair the flight performance of infected animals, and therefore, infected birds are expected to differ from their non-infected counterparts in migratory capacity. Since haemosporidians invade host erythrocytes, it is commonly assumed that infected individuals will have compromised aerobic capacity, but this has not been examined in free-living birds. We tested if haemosporidian infections affect aerobic performance by examining metabolic rates and exercise endurance in migratory great reed warblers (Acrocephalus arundinaceus) experimentally treated with Plasmodium relictum pGRW04 and in naturally infected wild birds over consecutive life-history stages. We found no effect of acute or chronic infections on resting metabolic rate, maximum metabolic rate or exercise endurance in either experimentally treated or free-living birds. Oxygen consumption rates during rest and while undergoing maximum exercise as well as exercise endurance increased from breeding to migration stages in both infected and non-infected birds. Importantly, phenotypic changes associated with preparation for migration were similarly unaffected by parasitaemia. Consequently, migratory birds experiencing parasitaemia levels typical of chronic infection do not differ in migratory capacity from their uninfected counterparts. Thus, if infected hosts differ from uninfected conspecifics in migration phenology, other mechanisms besides aerobic capacity should be considered. PMID:29386365

  11. Spatiotemporal Distributions of Migratory Birds: Patchy Models with Delay

    Science.gov (United States)

    Gourley, Stephen A.; Liu, Rongsong; Wu, Jianhong

    2010-01-01

    We derive and analyze a mathematical model for the spatiotemporal distribution of a migratory bird species. The birds have specific sites for breeding and winter feeding, and usually several stopover sites along the migration route, and therefore a patch model is the natural choice. However, we also model the journeys of the birds along the flyways, and this is achieved using a continuous space model of reaction-advection type. In this way proper account is taken of flight times and in-flight mortalities which may vary from sector to sector, and this information is featured in the ordinary differential equations for the populations on the patches through the values of the time delays and the model coefficients. The seasonality of the phenomenon is accommodated by having periodic migration and birth rates. The central result of the paper is a very general theorem on the threshold dynamics, obtained using recent results on discrete monotone dynamical systems, for birth functions which are subhomogeneous. For such functions, depending on the spectral radius of a certain operator, either there is a globally attracting periodic solution, or the bird population becomes extinct. Evaluation of the spectral radius is difficult, so we also present, for the particular case of just one stopover site on the migration route, a verifiable sufficient condition for extinction or survival in the form of an attractive periodic solution. This threshold is illustrated numerically using data from the U.S. Geological Survey on the bar-headed goose and its migration to India from its main breeding sites around Lake Qinghai and Mongolia.

  12. Hippocampal Astrocytes in Migrating and Wintering Semipalmated SandpiperCalidris 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. 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; 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

  14. Does hyperthermia constrain flight duration in a short-distance migrant?

    Science.gov (United States)

    Guillemette, Magella; Woakes, Anthony J; Larochelle, Jacques; Polymeropoulos, Elias T; Granbois, Jean-Marc; Butler, Patrick J; Pelletier, David; Frappell, Peter B; Portugal, Steven J

    2016-09-26

    While some migratory birds perform non-stop flights of over 11 000 km, many species only spend around 15% of the day in flight during migration, posing a question as to why flight times for many species are so short. Here, we test the idea that hyperthermia might constrain flight duration (FD) in a short-distance migrant using remote biologging technology to measure heart rate, hydrostatic pressure and body temperature in 19 migrating eider ducks (Somateria mollissima), a short-distance migrant. Our results reveal a stop-and-go migration strategy where migratory flights were frequent (14 flights day(-1)) and short (15.7 min), together with the fact that body temperature increases by 1°C, on average, during such flights, which equates to a rate of heat storage index (HSI) of 4°C h(-1) Furthermore, we could not find any evidence that short flights were limited by heart rate, together with the fact that the numerous stops could not be explained by the need to feed, as the frequency of dives and the time spent feeding were comparatively small during the migratory period. We thus conclude that hyperthermia appears to be the predominant determinant of the observed migration strategy, and suggest that such a physiological limitation to FD may also occur in other species.This article is part of the themed issue 'Moving in a moving medium: new perspectives on flight'. © 2016 The Author(s).

  15. Birds in portuguese literature

    OpenAIRE

    Queiroz, Ana Isabel; Soares, Filipa

    2016-01-01

    UID/ELT/00657/2013 WOS:000374914600004 IF/00222/2013 Birds are emblematic natural elements of landscapes. Readily noticeable and appreciated due to their songs and flight, they have been thoroughly used as components of literary scenarios. This paper analyses their representations in a broad corpus (144 writings by 67 writers) since the nineteenth century, divided in three time-periods. It aims to understand which wild birds are represented in Portuguese literature, how those represe...

  16. Some Ectoparasites of the Birds of Asia,

    Science.gov (United States)

    BIRDS, PARASITES, CLASSIFICATION, ARTHROPODA , DISTRIBUTION, FLIGHT, MITES, ECOLOGY, LICE, INDIA, JAPAN, TAIWAN, CHINA, PHILIPPINES, THAILAND, BORNEO, INDONESIA, SINGAPORE, ASIA, TABLES(DATA), HANDBOOKS, ARMY RESEARCH, DIPTERA.

  17. 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

  18. Constitutive immune function in European starlings, Sturnus vulgaris, is decreased immediately after an endurance flight in a wind tunnel.

    Science.gov (United States)

    Nebel, Silke; Bauchinger, Ulf; Buehler, Deborah M; Langlois, Lillie A; Boyles, Michelle; Gerson, Alexander R; Price, Edwin R; McWilliams, Scott R; Guglielmo, Christopher G

    2012-01-15

    Life-history theory predicts that animals face a trade-off in energy allocation between performing strenuous exercise, such as migratory flight, and mounting an immune response. We experimentally tested this prediction by studying immune function in European starlings, Sturnus vulgaris, flown in a wind tunnel. Specifically, we predicted that constitutive immune function decreases in response to training and, additionally, in response to immediate exercise. We compared constitutive immune function among three groups: (1) 'untrained' birds that were kept in cages and were not flown; (2) 'trained' birds that received flight training over a 15 day period and performed a 1-4 h continuous flight, after which they rested for 48 h before being sampled; and (3) 'post-flight' birds that differed from the 'trained' group only in being sampled immediately after the final flight. A bird in our trained group represents an individual during migration that has been resting between migratory flights for at least 2 days. A bird in our post-flight group represents an individual that has just completed a migratory flight and has not yet had time to recover. Three of our four indicators (haptoglobin, agglutination and lysis) showed the predicted decrease in immune function in the post-flight group, and two indicators (haptoglobin, agglutination) showed the predicted decreasing trend from the untrained to trained to post-flight group. Haptoglobin levels were negatively correlated with flight duration. No effect of training or flight was detected on leukocyte profiles. Our results suggest that in European starlings, constitutive immune function is decreased more as a result of immediate exercise than of exercise training. Because of the recent emergence of avian-borne diseases, understanding the trade-offs and challenges faced by long-distance migrants has gained a new level of relevance and urgency.

  19. 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,

  20. 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...

  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. It Takes Time to Be Cool: On the Relationship between Hyperthermia and Body Cooling in a Migrating Seaduck

    Directory of Open Access Journals (Sweden)

    Magella Guillemette

    2017-07-01

    Full Text Available The large amount of energy expended during flapping flight is associated with heat generated through the increased work of the flight muscles. This increased muscle work rate can manifest itself in core body temperature (Tb increase of 1–2°C in birds during flight. Therefore, episodic body cooling may be mandatory in migratory birds. To elucidate the thermoregulatory strategy of a short-distance migrant, common eiders (Somateria mollissima, we implanted data loggers in the body cavity of wild birds for 1 year, and report information on Tb during their entire migration for 19 individuals. We show that the mean body temperature during flight (TbMean in the eiders was associated with rises in Tb ranging from 0.2 to 1.5°C, largely depending on flight duration. To understand how eiders are dealing with hyperthermia during migration, we first compare, at a daily scale, how Tb differs during migration using a before-after approach. Only a slight difference was found (0.05°C between the after (40.30°C, the before (40.41°C and the migration (40.36°C periods, indicating that hyperthermia during flight had minimal impact at this time scale. Analyses at the scale of a flight cycle (flight plus stops on the water, however, clearly shows that eiders were closely regulating Tb during migration, as the relationship between the storage of heat during flight was highly correlated (slope = 1 with the level of heat dumping during stops, at both inter-individual and intra-individual levels. Because Tb at the start of a flight (TbStart was significantly and positively related to Tb at the end of a flight (TbEnd, and the maximal attained Tb during a flight (TbMax, we conclude that in absence of sufficient body cooling during stopovers, eiders are likely to become increasingly hyperthermic during migration. Finally, we quantified the time spent cooling down during migration to be 36% of their daily (24 h time budget, and conclude that behavioral body cooling in

  3. 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

  4. 14 CFR 35.36 - Bird impact.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Bird impact. 35.36 Section 35.36... STANDARDS: PROPELLERS Tests and Inspections § 35.36 Bird impact. The applicant must demonstrate, by tests or... 4-pound bird at the critical location(s) and critical flight condition(s) of a typical installation...

  5. Modeling the Geography of Migratory Pathways and Stopover Habitats for Neotropical Migratory Birds

    Directory of Open Access Journals (Sweden)

    Roger Tankersley, Jr.

    2003-07-01

    Full Text Available Intact migratory routes are critical for the stability of forest-dwelling, neotropical, migratory bird populations, and mortality along migratory pathways may be significant. Yet we know almost nothing about the geography of available stopovers or the possible migratory pathways that connect optimal stopovers. We undertake a spatial analysis of stopover habitat availability and then model potential migratory pathways between optimal stopovers in the eastern United States. Using models of fixed orientation and fixed nightly flight distance between stopovers during spring migration, we explore whether a simple endogenous migratory program is sufficient to ensure successful migration across the modern landscape. Our model runs suggest that the modern distribution of optimum stopovers in the eastern United States can be adequately exploited by birds following migratory pathways defined by fixed-orientation and fixed-distance nightly flights. Longer flight distances may increase the chances of success by enabling migrants to bypass locales offering little habitat. Our results also suggest that most southwest-northeast migratory pathways through the Appalachian mountains are intact. Lack of optimal habitat at key locations in the Southeast causes many modeled pathways to fail. We present a speculative view of regional migration patterns implied by predominant ideas found in stopover ecology literature, and demonstrate the need for broad-scale migration research, in the hope that our approach will foster other continental- and regional-scale projects.

  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. Autonomous Formation Flight

    Science.gov (United States)

    Schkolnik, Gerard S.; Cobleigh, Brent

    2004-01-01

    NASA's Strategic Plan for the Aerospace Technology Enterprise includes ambitious objectives focused on affordable air travel, reduced emissions, and expanded aviation-system capacity. NASA Dryden Flight Research Center, in cooperation with NASA Ames Research Center, the Boeing Company, and the University of California, Los Angeles, has embarked on an autonomous-formation-flight project that promises to make significant strides towards these goals. For millions of years, birds have taken advantage of the aerodynamic benefit of flying in formation. The traditional "V" formation flown by many species of birds (including gulls, pelicans, and geese) enables each of the trailing birds to fly in the upwash flow field that exists just outboard of the bird immediately ahead in the formation. The result for each trailing bird is a decrease in induced drag and thus a reduction in the energy needed to maintain a given speed. Hence, for migratory birds, formation flight extends the range of the system of birds over the range of birds flying solo. The Autonomous Formation Flight (AFF) Project is seeking to extend this symbiotic relationship to aircraft.

  8. 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.

  9. Screamy Bird

    DEFF Research Database (Denmark)

    Tarby, Sara; Cermak, Daniel

    2016-01-01

    Sara Tarby, Daniel Cermak-Sassenrath. Screamy Bird. Digital game. Kulturnatten 2016, Danish Science Ministry, Copenhagen, DK, Oct 14, 2016.......Sara Tarby, Daniel Cermak-Sassenrath. Screamy Bird. Digital game. Kulturnatten 2016, Danish Science Ministry, Copenhagen, DK, Oct 14, 2016....

  10. 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

  11. Toward conservation of midcontinental shorebird migrations

    Science.gov (United States)

    Skagen, Susan K.; Knopf, Fritz L.

    1993-01-01

    Shorebirds represent a highly diverse group of species, many of which experience tremendous energy demands associated with long-distance migratory flights. Transcontinental migrants are dependant upon dynamic freshwater wetlands for stopover resources essential for replenishment of lipid reserves and completion of migration. Patterns of shorebird migration across midcontinental wetlands were detected from migration reports to American Birds and information provided by U.S. Fish and Wildlife Service national wildlife refuges. Patterns in species composition and abundance varied geographically, emphasizing the uniqueness of different regions to migrating shorebirds. Smaller species and neotropical migrants moved primarily across the Great Plains, whereas larger species and North American migrants predominated in assemblages in the intermountain west. Shorebirds were broadly dispersed in wetland habitats with dynamic water regimes. Whereas populations of shorebirds in coastal system appear to concentrate at sites of seasonally predictable and abundant food resources, we propose that transcontinental shorebirds disperse and use wetlands opportunistically. This migration system exemplifies the need for large-scale, coordinated regional management efforts that recognize the dynamic nature of ecosystem processes.

  12. The microbiome of neotropical ticks parasitizing on passerine migratory birds

    OpenAIRE

    Budachetri, Khemraj; Williams, Jaclyn; Mukherjee, Nabanita; Sellers, Michael; Moore, Frank; Karim, Shahid

    2016-01-01

    Seasonal migration of passerine birds between temperate North America and tropical Central and South America is an ecological phenomenon. Migration of birds has been associated with the introduction of ectoparasites like ticks or tick-borne pathogens across the avian migration routes. In this study, the microbial diversity was determined in the ticks and bird DNA samples using 454 pyrosequencing of bacterial 16S rRNA gene. Tick DNA samples showed the dominance of genera Lactococcus, Francisel...

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

    NARCIS (Netherlands)

    G. Gunnarsson (Gunnar); N. Latorre-Margalef (Neus); K.A. Hobson (Keith); S.L. van Wilgenburg (Steven); J. Elmberg (Johan); B. Olsen (Björn); R.A.M. Fouchier (Ron); J. Waldenström (Jonas)

    2012-01-01

    textabstractThe 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

  14. Pointed wings, low wingloading and calm air reduce migratory flight costs in songbirds.

    Science.gov (United States)

    Bowlin, Melissa S; Wikelski, Martin

    2008-05-14

    Migratory bird, bat and insect species tend to have more pointed wings than non-migrants. Pointed wings and low wingloading, or body mass divided by wing area, are thought to reduce energy consumption during long-distance flight, but these hypotheses have never been directly tested. Furthermore, it is not clear how the atmospheric conditions migrants encounter while aloft affect their energy use; without such information, we cannot accurately predict migratory species' response(s) to climate change. Here, we measured the heart rates of 15 free-flying Swainson's Thrushes (Catharus ustulatus) during migratory flight. Heart rate, and therefore rate of energy expenditure, was positively associated with individual variation in wingtip roundedness and wingloading throughout the flights. During the cruise phase of the flights, heart rate was also positively associated with wind speed but not wind direction, and negatively but not significantly associated with large-scale atmospheric stability. High winds and low atmospheric stability are both indicative of the presence of turbulent eddies, suggesting that birds may be using more energy when atmospheric turbulence is high. We therefore suggest that pointed wingtips, low wingloading and avoidance of high winds and turbulence reduce flight costs for small birds during migration, and that climate change may have the strongest effects on migrants' in-flight energy use if it affects the frequency and/or severity of high winds and atmospheric instability.

  15. Pointed wings, low wingloading and calm air reduce migratory flight costs in songbirds.

    Directory of Open Access Journals (Sweden)

    Melissa S Bowlin

    Full Text Available Migratory bird, bat and insect species tend to have more pointed wings than non-migrants. Pointed wings and low wingloading, or body mass divided by wing area, are thought to reduce energy consumption during long-distance flight, but these hypotheses have never been directly tested. Furthermore, it is not clear how the atmospheric conditions migrants encounter while aloft affect their energy use; without such information, we cannot accurately predict migratory species' response(s to climate change. Here, we measured the heart rates of 15 free-flying Swainson's Thrushes (Catharus ustulatus during migratory flight. Heart rate, and therefore rate of energy expenditure, was positively associated with individual variation in wingtip roundedness and wingloading throughout the flights. During the cruise phase of the flights, heart rate was also positively associated with wind speed but not wind direction, and negatively but not significantly associated with large-scale atmospheric stability. High winds and low atmospheric stability are both indicative of the presence of turbulent eddies, suggesting that birds may be using more energy when atmospheric turbulence is high. We therefore suggest that pointed wingtips, low wingloading and avoidance of high winds and turbulence reduce flight costs for small birds during migration, and that climate change may have the strongest effects on migrants' in-flight energy use if it affects the frequency and/or severity of high winds and atmospheric instability.

  16. 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

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

    Science.gov (United States)

    Gill, Robert E.; Tibbitts, T. Lee; Douglas, David C.; Handel, Colleen M.; Mulcahy, Daniel M.; Gottschalck, Jon C.; Warnock, Nils; McCaffery, Brian J.; Battley, Philip F.; Piersma, Theunis

    2008-01-01

    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 8117–11 680 km (10 153±1043 s.d.) directly across the Pacific Ocean; two males with external transmitters flew non-stop along the same corridor for 7008–7390 km. 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. PMID:18974033

  18. 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.

  19. Contrasting extreme long-distance migration patterns in bar-tailed godwits Limosa lapponica

    Science.gov (United States)

    Battley, Phil F.; Warnock, Nils; Tibbitts, T. Lee; Gill, Robert E.; Piersma, Theunis; Hassell, Chris J.; Douglas, David C.; Mulcahy, Daniel M.; Gartrell, Brett D.; Schuckard, Rob; Melville, David S.; Riegen, Adrian C.

    2012-01-01

    Migrating birds make the longest non-stop endurance flights in the animal kingdom. Satellite technology is now providing direct evidence on the lengths and durations of these flights and associated staging episodes for individual birds. Using this technology, we compared the migration performance of two subspecies of bar-tailed godwit Limosa lapponica travelling between non-breeding grounds in New Zealand (subspecies baueri) and northwest Australia (subspecies menzbieri) and breeding grounds in Alaska and eastern Russia, respectively. Individuals of both subspecies made long, usually non-stop, flights from non-breeding grounds to coastal staging grounds in the Yellow Sea region of East Asia (average 10 060 ± SD 290 km for baueri and 5860 ± 240 km for menzbieri). After an average stay of 41.2 ± 4.8 d, baueri flew over the North Pacific Ocean before heading northeast to the Alaskan breeding grounds (6770 ± 800 km).Menzbieri staged for 38.4 ± 2.5 d, and flew over land and sea northeast to high arctic Russia (4170 ± 370 km). The post-breeding journey for baueri involved several weeks of staging in southwest Alaska followed by non-stop flights across the Pacific Ocean to New Zealand (11 690 km in a complete track) or stopovers on islands in the southwestern Pacific en route to New Zealand and eastern Australia. By contrast, menzbieri returned to Australia via stopovers in the New Siberian Islands, Russia, and back at the Yellow Sea; birds travelled on average 4510 ± 360 km from Russia to the Yellow Sea, staged there for 40.8 ± 5.6 d, and then flew another 5680–7180 km to Australia (10 820 ± 300 km in total). Overall, the entire migration of the single baueri godwit with a fully completed return track totalled 29 280 km and involved 20 d of major migratory flight over a round-trip journey of 174 d. The entire migrations of menzbieri averaged 21 940 ± 570 km, including 14 d of major migratory flights out of 154 d total. Godwits of both

  20. Lab-on-a-bird: biophysical monitoring of flying birds.

    Science.gov (United States)

    Gumus, Abdurrahman; Lee, Seoho; Ahsan, Syed S; Karlsson, Kolbeinn; Gabrielson, Richard; Guglielmo, Christopher G; Winkler, David W; Erickson, David

    2015-01-01

    The metabolism of birds is finely tuned to their activities and environments, and thus research on avian systems can play an important role in understanding organismal responses to environmental changes. At present, however, the physiological monitoring of bird metabolism is limited by the inability to take real-time measurements of key metabolites during flight. In this study, we present an implantable biosensor system that can be used for continuous monitoring of uric acid levels of birds during various activities including flight. The system consists of a needle-type enzymatic biosensor for the amperometric detection of uric acid in interstitial fluids. A lightweight two-electrode potentiostat system drives the biosensor, reads the corresponding output current and wirelessly transfers the data or records to flash memory. We show how the device can be used to monitor, in real time, the effects of short-term flight and rest cycles on the uric acid levels of pigeons. In addition, we demonstrate that our device has the ability to measure uric acid level increase in homing pigeons while they fly freely. Successful application of the sensor in migratory birds could open up a new way of studying birds in flight which would lead to a better understanding of the ecology and biology of avian movements.

  1. 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

  2. A Review of Research on Bird Impacting on Jet Engines

    Science.gov (United States)

    Jin, Yuecheng

    2018-03-01

    Bird strikes can lead to permanent deformations, sudden decrease of thrust, even engine failure during the flight. Bird strikes on rotating blades can also cause slices of birds hitting other parts which may lead to greater damages. Bird strikes cannot be completely avoided. However, reduction of bird impacting on jet engines can be achieved by suitable design and manufacturing, through the mathematical modelling, simulation analysis and practical experiment of jet engines.

  3. 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).

  4. Bird guard

    Science.gov (United States)

    Fairchild, Dana M [Armour, SD

    2010-03-02

    The bird guard provides a device to protect electrical insulators comprising a central shaft; a clamp attached to an end of the shaft to secure the device to a transmission tower; a top and bottom cover to shield transmission tower insulators; and bearings to allow the guard to rotate in order to frighten birds away from the insulators.

  5. 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.

  6. Residency patterns of migrating sandpipers at a midcontinental stopover

    Science.gov (United States)

    Skagen, Susan K.; Knopf, Fritz L.

    1994-01-01

    Arctic-nesting shorebirds require several refueling stops during their long migrations between breeding grounds and Central and South American wintering areas. The protection of stopover habitats for transcontinental migrants depends on whether birds fly long distances between a few select sites or fly short distances and stop at several wetlands. Although the Great Plains historically provided a vast array of wetlands for use by migrants, wetland loss and conversion have reduced the availability of stopover sites in recent decades. In this study, we examined (1) residency periods, (2) fat dynamics, and (3) migration chronology of two shorebird species, the Semipalmated Sandpiper (Calidris pusilla) and White-rumped Sandpiper (C. fuscicollis) at Quivira National Wildlife Refuge (NWR), Kansas. Semipalmated Sandpipers had prolonged periods of species residency with overlapping arrivals and departures. Individual residency periods were highly variable and were unrelated to lipid reserves upon arrival. In contrast, White-rumped Sandpipers arrived and departed more synchronously. Birds that arrived in poor condition stayed longer than those with more body fat in 1991, but not in 1992. Wind direction did not influence patterns of departures of either species. We hypothesize that Semipalmated Sandpipers are ecologically eurytopic when migrating across the Great Plains in the spring. Highly variable patterns in arrival, residency, and lipid levels indicate that spring migration of this species is relaxed and opportunistic. White-rumped Sandpipers showed a pattern of reduced flexibility. Flight range estimates suggest that most birds require intermediate stopovers before reaching the breeding grounds. Interior wetlands appear to function as migration stopovers rather than staging areas for shorebirds.

  7. Reed warbler orientation: initiation of nocturnal migratory flights in relation to visibility of celestial cues at dusk.

    Science.gov (United States)

    Åkesson, S.; Walinder, G.; Karlsson, L.; Ehnbom, S.

    2001-01-01

    We used radiotelemetry to investigate the time of migratory flight initiation relative to available celestial orientation cues and departure direction of a nocturnal passerine migrant, the reed warbler, Acrocephalus scirpaceus, during autumn migration. The study was carried out at Falsterbo, a coastal site in southwest Sweden. The warblers initiated migration from times well after local sunset and well into the night, corresponding to sun elevations between -4 degrees and -35 degrees, coinciding with the occurrence of stars at night. They departed in the expected migratory direction towards south of southwest with a few initiating migration in reverse directions towards northeast to east. Flight directions under overcast conditions (7-8/8) were more scattered than under clear sky conditions (0-4/8). There were fewer clouds on departure nights than on nights when the birds did not initiate migration. For birds staying longer than one night at stopover the horizontal visibility was higher and precipitation was less likely on departure nights than on the previous night. The results show that the visibility of celestial cues, and stars in particular, are important for the decision to initiate migration in reed warblers. However, cloud cover, horizontal visibility and precipitation might be correlated with other weather variables (i.e. wind or air pressure) that are also likely to be important for the decision to migrate. Copyright 2001 The Association for the Study of Animal Behaviour.

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

    Science.gov (United States)

    Williams, Augusta A.; Laird, Neil F.

    2017-10-01

    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.

  9. 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.

  10. 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.

  11. Body frontal area in passerine birds

    OpenAIRE

    Hedenström, Anders; Rosén, Mikael

    2003-01-01

    Projected body frontal area is used when estimating the parasite drag of bird flight. We investigated the relationship between projected frontal area and body mass among passerine birds, and compared it with an equation based on waterfowl and raptors, which is used as default procedure in a widespread software package for flight performance calculations. The allometric equation based on waterfowl/raptors underestimates the frontal area compared to the passerine equation presented here. Conseq...

  12. 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

  13. 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...

  14. Combined Fish and Birds survey in the Dutch coastal zone

    NARCIS (Netherlands)

    Ybema, M.S.; Couperus, A.S.; Grift, R.E.

    2004-01-01

    Knowledge on the relationship between birds and fish is important when assessing the impact of infrastructural development on birds and fish in the coastal zone. It can have a direct effect on bird migration routes and resting areas. It can also have an indirect effect by changing the fish community

  15. Predator escape tactics in birds : linking ecology and aerodynamics

    NARCIS (Netherlands)

    van den Hout, Piet J.; Mathot, Kimberley J.; Maas, Leo R. M.; Piersma, Theunis

    2010-01-01

    In most birds, flight is the most important means of escape from predators. Impaired flight abilities due to increased wing loading may increase vulnerability to predation. To compensate for an increase in wing loading, birds are able to independently decrease body mass (BM) or increase pectoral

  16. Birds and Wetlands of Alaska. Alaska Sea Week Curriculum Series. Alaska Sea Grant Report 88-1.

    Science.gov (United States)

    King, James G.; King, Mary Lou

    This curriculum guide is the fourth (Series V) in a six-volume set that comprises the Sea Week Curriculum Series developed in Alaska. Twelve units contain 45 activities with worksheets that cover the following topics: (1) bird lists and field guides; (2) definitions of a bird; (3) parts of a bird; (4) bird watching; (5) bird migration; (6) wetland…

  17. Risk Considerations of Bird Strikes to Space Launch Vehicles

    Science.gov (United States)

    Hales, Christy; Ring, Robert

    2016-01-01

    Within seconds after liftoff of the Space Shuttle during mission STS-114, a turkey vulture impacted the vehicle's external tank. The contact caused no apparent damage to the Shuttle, but the incident led NASA to consider the potential consequences of bird strikes during a Shuttle launch. The environment at Kennedy Space Center provides unique bird strike challenges due to the Merritt Island National Wildlife Refuge and the Atlantic Flyway bird migration routes. NASA is currently refining risk assessment estimates for the probability of bird strike to space launch vehicles. This paper presents an approach for analyzing the risks of bird strikes to space launch vehicles and presents an example. The migration routes, types of birds present, altitudes of those birds, exposed area of the launch vehicle, and its capability to withstand impacts affect the risk due to bird strike. A summary of significant risk contributors is discussed.

  18. Analysis of selective constraints on mitochondrial DNA, flight ability and physiological index on avian.

    Science.gov (United States)

    Zhang, Shanxin; Han, Jiuqiang; Zhong, Dexing; Wang, Tuo

    2013-01-01

    For most of the birds in the word, they can be divided into two main groups, i.e. resident birds and migratory ones. Most of the energy required for long-distance migration is supplied by mitochondria via oxidative phosphorylation. Therefore, the evolutionary constraints acted on the mitochondria DNA (mtDNA) are considered to vary with the locomotive abilities and flight speed. The flight speed is assumed to increase with mass and wing loading according to the fundamental aerodynamic theories, which is common between aves and aircrafts. We compared 148 avian mitochondrial genomes and main physiological parameters. More nonsynonymous nucleotide substitutions than synonymous ones are accumulated in low-speed and flightless birds rather than high-speed flying birds. No matter how the speed is obtained, directly measured or estimated through physiological index. Our results demonstrated that, besides artificial and environmental factors, selective constraints relevant to flight ability play an essential role in the evolution of mtDNA, even it might cause the extinction of avian species.

  19. 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.

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

    Directory of Open Access Journals (Sweden)

    Dongping Liu

    2018-01-01

    Full Text Available 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.

  1. Hawaii 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 endangered waterbirds and passerine birds, migratory shorebirds and waterfowl, gulls and terns,...

  2. 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.

  3. Tracking radar techniques for studying migratory birds

    Science.gov (United States)

    Williams, T. C.; Williams, J. M.

    1972-01-01

    The use of NASA tracking radar at Wallops Island and the islands of Bermuda and Antigua to plot the paths of migatory birds in three dimensional space is discussed. Attempts were also made to obtain data on the direction, speed, and density of large numbers of migrating birds. Observational results show that the performance of tracking radars vary considerably with the density of bird migration. At light to moderate levels of migration it is possible to obtain tracks of a variety of types of targets, both large and small. During heavy periods of migration the sky is so filled with targets, that only the largest targets can be tracked for more than a few minutes.

  4. 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

  5. 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.

  6. The flight apparatus of migratory and sedentary individuals of a partially migratory songbird species.

    Directory of Open Access Journals (Sweden)

    Adam M Fudickar

    Full Text Available Variations in the geometry of the external flight apparatus of birds are beneficial for different behaviors. Long-distance flight is less costly with more pointed wings and shorter tails; however these traits decrease maneuverability at low speeds. Selection has led to interspecific differences in these and other flight apparatuses in relation to migration distance. If these principles are general, how are the external flight apparatus within a partially migratory bird species shaped in which individuals either migrate or stay at their breeding grounds? We resolved this question by comparing the wing pointedness and tail length (relative to wing length of migrant and resident European blackbirds (Turdus merula breeding in the same population. We predicted that migrant blackbirds would have more pointed wings and shorter tails than residents. Contrary to our predictions, there were no differences between migrants and residents in either measure. Our results indicate that morphological differences between migrants and residents in this partially migratory population may be constrained.

  7. What makes Alpine swift ascend at twilight? Novel geolocators reveal year-round flight behaviour.

    Science.gov (United States)

    Meier, Christoph M; Karaardıç, Hakan; Aymí, Raül; Peev, Strahil G; Bächler, Erich; Weber, Roger; Witvliet, Willem; Liechti, Felix

    2018-01-01

    Studying individual flight behaviour throughout the year is indispensable to understand the ecology of a bird species. Recent development in technology allows now to track flight behaviour of small long-distance bird migrants throughout its annual cycle. The specific flight behaviour of twilight ascents in birds has been documented in a few studies, but only during a short period of the year, and never quantified on the individual level. It has been suggested that twilight ascents might be a role in orientation and navigation. Previous studies had reported the behaviour only near the breeding site and during migration. We investigated year-round flight behaviour of 34 individual Alpine swifts ( Apus melba ) of four different populations in relation to twilight ascents. We recorded twilight ascents all around the year and found a twofold higher frequency in ascents during the non-breeding residence phase in Africa compared to all other phases of the year. Dawn ascents were twice as common as dusk ascents and occurred mainly when atmospheric conditions remained stable over a 24-h period. We found no conclusive support that twilight ascents are essential for recalibration of compass cues and landmarks. Data on the wing flapping intensity revealed that high activity at twilight occurred more regularly than the ascents. We therefore conclude that alpine swift generally increase flight activity-also horizontal flight-during the twilight period and we suppose that this increased flight activity, including ascents, might be part of social interactions between individuals. Year-round flight altitude tracking with a light-weight multi-sensor tag reveals that Alpine swifts ascend several hundred meters high at twilight regularly. The reason for this behaviour remains unclear and the low-light conditions at this time of the day preclude foraging as a possibility. The frequency and altitude of twilight ascents were highest during the non-breeding period, intermediate during

  8. Migration and breeding biology of Arctic terns in Greenland

    DEFF Research Database (Denmark)

    Egevang, Carsten

    ) in the central part of the North Atlantic Ocean before continuing south. Close to Equator (~10º N) a divide in the migration path way occurred: seven birds migrated along the coast of Africa, while four birds crossed the Atlantic Ocean to follow the coast of South America. The northbound migration from...... scale and on a national scale. The study on Arctic tern migration (Manus I) – the longest annual migration ever recorded in any animal – is a study with an international appeal. The study documented how Greenland and Iceland breeding terns conduct the roundtrip migration to the Weddell Sea in Antarctica...... and back. Although the sheer distance (71,000 km on average) travelled by the birds is interesting, the study furthermore showed how the terns depend on high-productive at-sea areas during their massive migration. On the southbound migration, the birds would stop for almost a month (25 days on average...

  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, John Y.; Natsagdorj, T.; Wikelski, M.; Witt, M.J.; Yan, B.; Bishop, C.M.

    2012-01-01

    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.

  10. Utilization Probability Map for Migrating Bald Eagles in Northeastern North America: A Tool for Siting Wind Energy Facilities and Other Flight Hazards.

    Science.gov (United States)

    Mojica, Elizabeth K; Watts, Bryan D; Turrin, Courtney L

    2016-01-01

    Collisions with anthropogenic structures are a significant and well documented source of mortality for avian species worldwide. The bald eagle (Haliaeetus leucocephalus) is known to be vulnerable to collision with wind turbines and federal wind energy guidelines include an eagle risk assessment for new projects. To address the need for risk assessment, in this study, we 1) identified areas of northeastern North America utilized by migrating bald eagles, and 2) compared these with high wind-potential areas to identify potential risk of bald eagle collision with wind turbines. We captured and marked 17 resident and migrant bald eagles in the northern Chesapeake Bay between August 2007 and May 2009. We produced utilization distribution (UD) surfaces for 132 individual migration tracks using a dynamic Brownian bridge movement model and combined these to create a population wide UD surface with a 1 km cell size. We found eagle migration movements were concentrated within two main corridors along the Appalachian Mountains and the Atlantic Coast. Of the 3,123 wind turbines ≥100 m in height in the study area, 38% were located in UD 20, and 31% in UD 40. In the United States portion of the study area, commercially viable wind power classes overlapped with only 2% of the UD category 20 (i.e., the areas of highest use by migrating eagles) and 4% of UD category 40. This is encouraging because it suggests that wind energy development can still occur in the study area at sites that are most viable from a wind power perspective and are unlikely to cause significant mortality of migrating eagles. In siting new turbines, wind energy developers should avoid the high-use migration corridors (UD categories 20 & 40) and focus new wind energy projects on lower-risk areas (UD categories 60-100).

  11. Utilization Probability Map for Migrating Bald Eagles in Northeastern North America: A Tool for Siting Wind Energy Facilities and Other Flight Hazards.

    Directory of Open Access Journals (Sweden)

    Elizabeth K Mojica

    Full Text Available Collisions with anthropogenic structures are a significant and well documented source of mortality for avian species worldwide. The bald eagle (Haliaeetus leucocephalus is known to be vulnerable to collision with wind turbines and federal wind energy guidelines include an eagle risk assessment for new projects. To address the need for risk assessment, in this study, we 1 identified areas of northeastern North America utilized by migrating bald eagles, and 2 compared these with high wind-potential areas to identify potential risk of bald eagle collision with wind turbines. We captured and marked 17 resident and migrant bald eagles in the northern Chesapeake Bay between August 2007 and May 2009. We produced utilization distribution (UD surfaces for 132 individual migration tracks using a dynamic Brownian bridge movement model and combined these to create a population wide UD surface with a 1 km cell size. We found eagle migration movements were concentrated within two main corridors along the Appalachian Mountains and the Atlantic Coast. Of the 3,123 wind turbines ≥100 m in height in the study area, 38% were located in UD 20, and 31% in UD 40. In the United States portion of the study area, commercially viable wind power classes overlapped with only 2% of the UD category 20 (i.e., the areas of highest use by migrating eagles and 4% of UD category 40. This is encouraging because it suggests that wind energy development can still occur in the study area at sites that are most viable from a wind power perspective and are unlikely to cause significant mortality of migrating eagles. In siting new turbines, wind energy developers should avoid the high-use migration corridors (UD categories 20 & 40 and focus new wind energy projects on lower-risk areas (UD categories 60-100.

  12. 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...

  13. 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...

  14. Birds Kept as Pets

    Science.gov (United States)

    ... of pet birds. Because of the risk of avian influenza (bird flu), USDA restricts the importation of pet birds from ... or look dirty may be ill. Learn the signs of illness in a bird, which include appearing ...

  15. 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.

  16. 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.

  17. Ecophysiology of avian migration in the face of current global hazards.

    Science.gov (United States)

    Klaassen, Marcel; Hoye, Bethany J; Nolet, Bart A; Buttemer, William A

    2012-06-19

    Long-distance migratory birds are often considered extreme athletes, possessing a range of traits that approach the physiological limits of vertebrate design. In addition, their movements must be carefully timed to ensure that they obtain resources of sufficient quantity and quality to satisfy their high-energy needs. Migratory birds may therefore be particularly vulnerable to global change processes that are projected to alter the quality and quantity of resource availability. Because long-distance flight requires high and sustained aerobic capacity, even minor decreases in vitality can have large negative consequences for migrants. In the light of this, we assess how current global change processes may affect the ability of birds to meet the physiological demands of migration, and suggest areas where avian physiologists may help to identify potential hazards. Predicting the consequences of global change scenarios on migrant species requires (i) reconciliation of empirical and theoretical studies of avian flight physiology; (ii) an understanding of the effects of food quality, toxicants and disease on migrant performance; and (iii) mechanistic models that integrate abiotic and biotic factors to predict migratory behaviour. Critically, a multi-dimensional concept of vitality would greatly facilitate evaluation of the impact of various global change processes on the population dynamics of migratory birds.

  18. Evidence that dorsally mounted satellite transmitters affect migration chronology of Northern Pintails

    Science.gov (United States)

    Hupp, Jerry; Kharitonov, Sergei; Yamaguchi, Noriyuki M.; Ozaki, K.; Flint, Paul L.; Pearce, John M.; Tokita, Ken-ichi; Shimada, Tetsuo; Higuchi, Hiroyoshi

    2015-01-01

    We compared migration movements and chronology between Northern Pintails (Anas acuta) marked with dorsally mounted satellite transmitters and pintails marked only with tarsus rings. During weekly intervals of spring and autumn migration between their wintering area in Japan and nesting areas in Russia, the mean distance that ringed pintails had migrated was up to 1000 km farther than the mean distance radiomarked pintails migrated. Radiomarked pintails were detected at spring migration sites on average 9.9 days (90 % CI 8.0, 11.8) later than ringed pintails that were recovered within 50 km. Although ringed and radiomarked pintails departed from Japan on similar dates, the disparity in detection of radiomarked versus ringed pintails at shared sites increased 7.7 days (90 % CI 5.2, 10.2) for each 1000 km increase in distance from Japan. Thus, pintails marked with satellite transmitters arrived at nesting areas that were 2500 km from Japan on average 19 days later than ringed birds. Radiomarked pintails were detected at autumn migration stopovers on average 13.1 days (90 % CI 9.8, 16.4) later than ringed birds that were recovered within 50 km. We hypothesize that dorsal attachment of 12–20 g satellite transmitters to Northern Pintails increased the energetic cost of flight, which resulted in more rapid depletion of energetic reserves and shortened the distance pintails could fly without refueling. Radiomarked pintails may have used more stopovers or spent longer periods at stopovers. causing their migration schedule to diverge from ringed pintails. We urge further evaluation of the effects of dorsally mounted transmitters on migration chronology of waterfowl.

  19. Budgerigar flight in a varying environment: flight at distinct speeds?

    Science.gov (United States)

    Srinivasan, Mandyam V.

    2016-01-01

    How do flying birds respond to changing environments? The behaviour of budgerigars, Melopsittacus undulatus, was filmed as they flew through a tapered tunnel. Unlike flying insects—which vary their speed progressively and continuously by holding constant the optic flow induced by the walls—the birds showed a tendency to fly at only two distinct, fixed speeds. They switched between a high speed in the wider section of the tunnel, and a low speed in the narrower section. The transition between the two speeds was abrupt, and anticipatory. The high speed was close to the energy-efficient, outdoor cruising speed for these birds, while the low speed was approximately half this value. This is the first observation of the existence of two distinct, preferred flight speeds in birds. A dual-speed flight strategy may be beneficial for birds that fly in varying environments, with the high speed set at an energy-efficient value for flight through open spaces, and the low speed suited to safe manoeuvring in a cluttered environment. The constancy of flight speed within each regime enables the distances of obstacles and landmarks to be directly calibrated in terms of optic flow, thus facilitating simple and efficient guidance of flight through changing environments. PMID:27330173

  20. 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...... rhythms of migratory flights, as well as prolonged nocturnal flights across desert barriers are illustrated. The shifting balance between flight, rest and different intensities of activity throughout the year as revealed by actogram data can be used to analyse exertion levels during different phases...

  1. An integrative approach to understanding bird origins.

    Science.gov (United States)

    Xu, Xing; Zhou, Zhonghe; Dudley, Robert; Mackem, Susan; Chuong, Cheng-Ming; Erickson, Gregory M; Varricchio, David J

    2014-12-12

    Recent discoveries of spectacular dinosaur fossils overwhelmingly support the hypothesis that birds are descended from maniraptoran theropod dinosaurs, and furthermore, demonstrate that distinctive bird characteristics such as feathers, flight, endothermic physiology, unique strategies for reproduction and growth, and a novel pulmonary system originated among Mesozoic terrestrial dinosaurs. The transition from ground-living to flight-capable theropod dinosaurs now probably represents one of the best-documented major evolutionary transitions in life history. Recent studies in developmental biology and other disciplines provide additional insights into how bird characteristics originated and evolved. The iconic features of extant birds for the most part evolved in a gradual and stepwise fashion throughout archosaur evolution. However, new data also highlight occasional bursts of morphological novelty at certain stages particularly close to the origin of birds and an unavoidable complex, mosaic evolutionary distribution of major bird characteristics on the theropod tree. Research into bird origins provides a premier example of how paleontological and neontological data can interact to reveal the complexity of major innovations, to answer key evolutionary questions, and to lead to new research directions. A better understanding of bird origins requires multifaceted and integrative approaches, yet fossils necessarily provide the final test of any evolutionary model. Copyright © 2014, American Association for the Advancement of Science.

  2. 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.

  3. Bird feeders and their effects on bird-window collisions at residential houses

    Directory of Open Access Journals (Sweden)

    Justine A. Kummer

    2015-12-01

    Full Text Available Feeding wild birds creates an important link between homeowners and conservation. The effects of bird feeders and year-round feeding on birds have not been well studied, however, particularly in relationship to bird-window collisions. We determined effects of bird feeder presence and placement on bird-window collisions at residential homes. Paired month-long trials in which a feeder was either present or absent for one month and then removed or added for the second month were completed at 55 windows at 43 houses. In each trial, homeowners were asked to search their study window daily for evidence of a bird-window collision. During the study there were 51 collisions when there was no bird feeder and 94 when the feeder was present. The season when each trial was set up was the best individual predictor of bird-window collisions. The largest number of collisions was observed during fall migration and the lowest during the winter months. There were no collisions at 26 of the study windows. High variance was observed in the number of collisions at different houses, indicating that effects of bird feeders are context dependent. Changing the occurrence, timing, and placement of feeders can alter collision rates but is only one of many factors that influence whether a residential house is likely to have a bird window-collision or not.

  4. Migration et hivernage de quelques passereaux au Maroc: Mise au ...

    African Journals Online (AJOL)

    The analysis of the autumn migration across Morocco confirms that many birds pass near the Atlantic coast. Winter recoveries in Morocco are mainly concentrated in the northern and central regions. The analysis of the spring migration shows that most birds use approximately the same routes in both autumn and spring, but ...

  5. Assessment of bird response to the Migratory Bird Habitat Initiative using weather-surveillance radar

    Science.gov (United States)

    Sieges, Mason L.; Smolinsky, Jaclyn A.; Baldwin, Michael J.; Barrow, Wylie C.; Randall, Lori A.; Buler, Jeffrey J.

    2014-01-01

    In response to the Deepwater Horizon oil spill in spring 2010, the Natural Resources Conservation Service implemented the Migratory Bird Habitat Initiative (MBHI) to provide temporary wetland habitat for migrating and wintering waterfowl, shorebirds, and other birds along the northern Gulf of Mexico via managed flooding of agricultural lands. We used weather-surveillance radar to conduct broad regional assessments of bird response to MBHI activities within the Mississippi Alluvial Valley and the West Gulf Coastal Plain. Across both regions, birds responded positively to MBHI management by exhibiting greater relative bird densities within sites relative to pre-management conditions in prior years and relative to surrounding non-flooded agricultural lands. Bird density at MBHI sites was generally greatest during winter for both regions. Unusually high flooding in the years prior to implementation of the MBHI confounded detection of overall changes in remotely sensed soil wetness across sites. The magnitude of bird response at MBHI sites compared to prior years and to non-flooded agricultural lands was generally related to the surrounding landscape context: proximity to areas of high bird density, amount of forested wetlands, emergent marsh, non-flooded agriculture, or permanent open water. However, these relationships varied in strength and direction between regions and seasons, a finding which we attribute to differences in seasonal bird composition and broad regional differences in landscape configuration and composition. We detected greater increases in relative bird use at sites in closer proximity to areas of high bird density during winter in both regions. Additionally, bird density was greater during winter at sites with more emergent marsh in the surrounding landscape. Thus, bird use of managed wetlands could be maximized by enrolling lands located near areas of known bird concentration and within a mosaic of existing wetlands. Weather-radar observations

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

    Science.gov (United States)

    Landys, Meta M; Piersma, Theunis; Guglielmo, Christopher G; Jukema, Joop; Ramenofsky, Marilyn; Wingfield, John C

    2005-02-07

    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 flight to their single spring stopover site and thus provide an excellent model in which to determine the energy fuels associated with endurance travel. To this end, we evaluated plasma concentrations of six key metabolites in arriving godwits caught immediately upon landing near their stopover site. Initial metabolite levels were compared with levels after 5 h of inactive rest to determine how flight per se affects energy metabolism. Birds refuelling on the stopover site were also examined. Arriving godwits displayed elevated plasma free fatty acids, glycerol and butyrate, confirming the importance of lipid fuel in the support of extended migratory activity. Further-more, elevated plasma triglycerides in these birds suggest that fatty acid provisioning is facilitated through hepatic synthesis and release of neutral lipids, as previously hypothesized for small migrants with high mass-specific metabolic rates. Finally, elevations in plasma uric acid suggest that protein breakdown contributes to the support of long-distance movement, to possibly maintain citric acid cycle intermediates, gluconeogenesis and/or water balance.

  7. 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 migration status accounting for only 1% of 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

  8. Crossing the ultimate ecological barrier: Evidence for an 11,000-km-long non-stop flight from Alaska to New Zealand and Eastern Australia by Bar-tailed Godwits

    Science.gov (United States)

    Gill, Robert E.; Piersma, Theunis; Hufford, Gary; Servranckx, R.; Riegen, Adrian C.

    2005-01-01

    Populations of the Bar-tailed Godwit (Limosa lapponica; Scolopacidae) embark on some of the longest migrations known among birds. The baueri race breeds in westernAlaska and spends the nonbreeding season a hemisphere away inNew Zealand and eastern Australia; the menzbieri race breeds in Siberia and migrates to western and northern Australia. Although the Siberian birds are known to follow the coast of Asia during both migrations, the southern pathway followed by the Alaskabreeders has remained unknown. Two questions have particularecological importance: (1) do Alaska godwits migrate directly across the Pacific, a distance of 11 000 km? and (2) are they capable of doing this in a single flight without stopping to rest or refuel? We explored six lines of evidence to answer these questions. The distribution of resightings of marked birds of the baueri and menzbieri races was significantly different between northward and southward flights with virtually no marked baueri resighted along the Asian mainland during southward migration. The timing of southward migration of the two races further indicates the absence of a coastal Asia route by baueri with peak passage of godwits in general occurring there a month prior to the departure of most birds from Alaska. The use of a direct route across the Pacific is also supported by significantly more records of godwits reported from within a direct migration corridor than elsewhere in Oceania, and during the September to November period than at other times of the year. The annual but rare occurrence of Hudsonian Godwits (L. haemastica) in New Zealand and the absence of their records along the Asian mainland also support a direct flight and are best explained by Hudsonian Godwits accompanying Bar-tailed Godwits from known communal staging areas in Alaska. Flight simulation models, extreme fat loads, and the apparent evolution of a wind-selected migration from Alaska further support a direct, nonstop flight.

  9. 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.

  10. Baseline corticosterone peaks in shorebirds with maximal energy stores for migration: a general preparatory mechanism for rapid behavioral and metabolic transitions?

    Science.gov (United States)

    Piersma, T; Reneerkens, J; Ramenofsky, M

    2000-10-01

    In captive red knots (Calidris canutus, Scolopacidae) showing a regulated body mass increase of 50% related to their migration from temperate staging sites to tundra breeding grounds, plasma corticosterone concentrations increased from less than 10 ng. ml(-1) to levels as high as 30 ng. ml(-1) when the energy storage for migration was complete. These birds did not fly, but concentrations dropped to very low levels (<5 ng. ml(-1)) as soon as the birds started their voluntary fasts to the low body masses preceding the early wing and body molts normally occurring after an unsuccessful breeding season. As the elevated levels of corticosterone are associated with stable body mass rather than with the preceding increase or subsequent decrease, it is suggested that a major role of corticosterone during the final stages just before departure may be to prepare birds for long-distance flights. Birds heading into the Arctic to breed face potentially arduous flights into unpredictable environmental and social conditions. Activation of the hypothalamic-pituitary-adrenal axis, as measured by elevated levels of corticosterone, may induce the suite of behavioral and metabolic changes necessary to negotiate these challenges successfully. Copyright 2000 Academic Press.

  11. Results of the Utah-Arizona stage-by-stage migrations

    Science.gov (United States)

    Ellis, D.H.; Mellon, C.; Kinloch, M.; Dolbeare, T.; Ossi, D.P.

    2001-01-01

    In an effort to find a safer means of teaching cranes new migration routes, each year (in 1998 and 1999) we transported a group of greater sandhill cranes (Grus canadensis tabida) stage-by-stage, in a horse trailer, with stops for brief flights at about 30-km intervals, along a 1300-1400-km fall migration route from Fish Springs National Wildlife Refuge (Fish Springs) in west-central Utah to the vicinity of Gila Bend, Arizona. Thereafter, we released them into a wild flock of sandhill cranes. All stage-by-stage birds were hand-reared with both a plastic crane decoy (to encourage them to roost in water) and a costume-draped humanoid form (called a scare-eagle and used for its namesake purpose). When these 2 teaching aids were placed in water, our cranes readily roosted nearby. All but 4 of our cranes proved cooperative (i.e., catchable at each of the ca 25-36 stops) during the migration. All were efficiently released into a wild flock and experienced good survival. The stage-by-stage method proved to be a safe means of transporting cranes south and giving them experience along the route. Some cranes apparently learned their route from the limited experience afforded by releasing them at intervals, and the 1999 cranes have made repealed migrations to or near our chosen northern terminus. However, after 1 winter in our chosen area, the birds have moved elsewhere to winter.

  12. 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...

  13. 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.

  14. Estimating updraft velocity components over large spatial scales: contrasting migration strategies of golden eagles and turkey vultures.

    Science.gov (United States)

    Bohrer, Gil; Brandes, David; Mandel, James T; Bildstein, Keith L; Miller, Tricia A; Lanzone, Michael; Katzner, Todd; Maisonneuve, Charles; Tremblay, Junior A

    2012-02-01

    Soaring birds migrate in massive numbers worldwide. These migrations are complex and dynamic phenomena, strongly influenced by meteorological conditions that produce thermal and orographic uplift as the birds traverse the landscape. Herein we report on how methods were developed to estimate the strength of thermal and orographic uplift using publicly available digital weather and topography datasets at continental scale. We apply these methods to contrast flight strategies of two morphologically similar but behaviourally different species: golden eagle, Aquila chrysaetos, and turkey vulture, Cathartes aura, during autumn migration across eastern North America tracked using GPS tags. We show that turkey vultures nearly exclusively used thermal lift, whereas golden eagles primarily use orographic lift during migration. It has not been shown previously that migration tracks are affected by species-specific specialisation to a particular uplift mode. The methods introduced herein to estimate uplift components and test for differences in weather use can be applied to study movement of any soaring species. © 2011 Blackwell Publishing Ltd/CNRS.

  15. 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 ...

  16. 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, ...

  17. Using a Convection Model to Predict Altitudes of White Stork Migration Over Central Israel

    Science.gov (United States)

    Shamoun-Baranes, Judy; Liechti, Olivier; Yom-Tov, Yoram; Leshem, Yossi

    Soaring migrants such as storks, pelicans and large birds of prey rely on thermal convection during migration. The convection model ALPTHERM was designed to predict the onset, strength, duration and depth of thermal convection for varying topographies for glider pilots, based on atmospheric conditions at midnight. We tested ALPTHERM predictions as configured for two topographies of central Israel, the Coastal Plains and the Judean and Samarian Mountains in order to predict altitudes of migrating white storks (Ciconia ciconia). Migrating flocks of white storks were tracked with a motorized glider, to measure maximum altitudes of migration during spring 2000. A significant positive correlation was found between the maximum daily altitudes of migration measured and the predicted upper boundary of thermal convection for the Coastal Plains and Samarian Mountains. Thirty-minute predictions for the Coastal Plains and Samarian Mountains correlated positively with measured maximum migration altitudes per thermal. ALPTHERM forecasts can be used to alter flight altitudes in both civil and especially military aviation and reduce the hazard of serious aircraft collisions with soaring migrants.

  18. 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

  19. 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...

  20. Burning for birds: concepts and applications

    Science.gov (United States)

    R. Todd Engstrom; David J. Brownlie

    2002-01-01

    Prescribed fire is being used extensively for habitat management of non-game birds, although the area burned today is small relative to the amount of land that burned historically. Results of a non-scientific questionnaire of public and private land managers in the eastern U.S. revealed prescribed fire is being used to provide winter, breeding season, and migration...

  1. 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

  2. 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 ...

  3. Detection of tick-borne encephalitis virus in I. ricinus ticks collected from autumn migratory birds in Latvia.

    Science.gov (United States)

    Kazarina, Alisa; Japiņa, Kristīne; Keišs, Oskars; Salmane, Ineta; Bandere, Dace; Capligina, Valentina; Ranka, Renāte

    2015-03-01

    Birds have a potential of spreading ticks via bird migration routes. In this study, we screened 170 ticks removed during autumn 2010 from 55 birds belonging to 10 species for the presence of tick-borne encephalitis virus (TBEV). In total, TBEV RNA was detected in 14% of I. ricinus tick samples obtained from different birds species. The results of this study indicate the possible role of migrating birds in the dispersal of TBEV-infected ticks along the southward migration route. Copyright © 2014 Elsevier GmbH. All rights reserved.

  4. 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)

  5. 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)

  6. Songbirds are resilient to hurricane disturbed habitats during spring migration

    Science.gov (United States)

    Lain, Emily; Zenzal, Theodore J.; Moore, Frank R.; Barrow, Wylie C.; Diehl, Robert H.

    2017-01-01

    The Gulf of Mexico is a conspicuous feature of the Neotropical–Nearctic bird migration system. Traveling long distances across ecological barriers comes with considerable risks, and mortality associated with intercontinental migration may be substantial, including that caused by storms or other adverse weather events. However, little, if anything, is known about how migratory birds respond to disturbance-induced changes in stopover habitat. Isolated, forested cheniere habitat along the northern coast of the Gulf of Mexico often concentrate migrants, during weather conditions unfavorable for northward movement or when birds are energetically stressed. We expected hurricane induced degradation of this habitat to negatively affect the abundance, propensity to stopover, and fueling trends of songbirds that stopover in coastal habitat. We used spring banding data collected in coastal Louisiana to compare migrant abundance and fueling trends before (1993–1996 and 1998–2005) and after hurricanes Rita (2006) and Ike (2009). We also characterized changes in vegetative structure before (1995) and after (2010) the hurricanes. The hurricanes caused dramatic changes to the vegetative structure, which likely decreased resources. Surprisingly, abundance, propensity to stopover, and fueling trends of most migrant species were not influenced by hurricane disturbance. Our results suggest that: 1) the function of chenieres as a refuge for migrants after completing a trans-Gulf flight may not have changed despite significant changes to habitat and decreases in resource availability, and 2) that most migrants may be able to cope with habitat disturbance during stopover. The fact that migrants use disturbed habitat points to their conservation value along the northern coast of the Gulf of Mexico.

  7. 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)

  8. The mechanics and behavior of cliff swallows during tandem flights.

    Science.gov (United States)

    Shelton, Ryan M; Jackson, Brandon E; Hedrick, Tyson L

    2014-08-01

    Cliff swallows (Petrochelidon pyrrhonota) are highly maneuverable social birds that often forage and fly in large open spaces. Here we used multi-camera videography to measure the three-dimensional kinematics of their natural flight maneuvers in the field. Specifically, we collected data on tandem flights, defined as two birds maneuvering together. These data permit us to evaluate several hypotheses on the high-speed maneuvering flight performance of birds. We found that high-speed turns are roll-based, but that the magnitude of the centripetal force created in typical maneuvers varied only slightly with flight speed, typically reaching a peak of ~2 body weights. Turning maneuvers typically involved active flapping rather than gliding. In tandem flights the following bird copied the flight path and wingbeat frequency (~12.3 Hz) of the lead bird while maintaining position slightly above the leader. The lead bird turned in a direction away from the lateral position of the following bird 65% of the time on average. Tandem flights vary widely in instantaneous speed (1.0 to 15.6 m s(-1)) and duration (0.72 to 4.71 s), and no single tracking strategy appeared to explain the course taken by the following bird. © 2014. Published by The Company of Biologists Ltd.

  9. Torn Paper Birds.

    Science.gov (United States)

    Harrington, Carolyn Lang

    1998-01-01

    Describes a lesson for third-grade students that begins with an examination of bird prints done by John James Audubon and moves into the students creating their own torn paper birds. Introduces the students to the beauty of birds and focuses on the environmental issues that face birds and their habitats. (CMK)

  10. 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

  11. Crossing the Borders: An Eco-cinecritical Analysis of Plant Wars and Bird Without Borders

    Directory of Open Access Journals (Sweden)

    Hsiao-Ching Li

    2011-01-01

    Full Text Available This essay reads two Asian nature-oriented films from the perspective of ecocinecriticism,an ecologically minded film criticism. Plant Wars, produced by PTSTaiwan, questions the demarcation between native plants and exotic plants as well asbetween plants and human beings so as to remap the in-between border area. Thestorytelling method it applies is to feature 14 currently native plants as the maincharacters, and illustrates their relationship to aboriginal people, farmers, beekeepersand to other insect species. Bird Without Borders, also produced by PTS, tells the storyof the migration journey of a group of black-faced spoonbills flying 16,000 kilometersall the way from Tainan, Taiwan, to Japan, along the border of South and North Korea,to a remote island of China to look for feeding places and then back to Taiwan to spendthe winter. Different layers of border-crossing are shown in Bird. One similarity ofthese two PTS productions is the search for border-crossing so as to redefine or revisewhat the border means. Plant questions the biological categorization of the native plantsand the exotic plants; Bird illustrates how the crew physically follows the route of thebirds’ flight which crosses the national borders to provide a vision of remapping thenatural territory through challenging the idea of a fixed “place.” Both are seeking forways to trespass the man-made borders: Plant via environmental imagination; Bird viasome physical movement. While the title of Plant Wars seemingly expresses its positionmore strongly through “wars,” Bird Without Borders explicitly asserts a dream of noborders.

  12. Migration, mitochondria, and the yellow-rumped warbler.

    Science.gov (United States)

    Toews, David P L; Mandic, Milica; Richards, Jeffrey G; Irwin, Darren E

    2014-01-01

    Discordance between mitochondrial and nuclear DNA has been noted in many systems. Asymmetric introgression of mitochondria is a common cause of such discordances, although in most cases the drivers of introgression are unknown. In the yellow-rumped warbler, evidence suggests that mtDNA from the eastern, myrtle warbler, has introgressed across much of the range of the western form, the Audubon's warbler. Within the southwestern United States myrtle mtDNA comes into contact with another clade that occurs in the Mexican black-fronted warbler. Both northern forms exhibit seasonal migration, whereas black-fronted warblers are nonmigratory. We investigated the link between mitochondrial introgression, mitochondrial function, and migration using novel genetic, isotopic, biochemical, and phenotypic data obtained from populations in the transition zone. Isotopes suggest the zone is coincident with a shift in migration, with individuals in the south being resident and populations further north becoming increasingly more migratory. Mitochondrial respiration in flight muscles demonstrates that myrtle-type individuals have a significantly greater acceptor control ratio of mitochondria, suggesting it may be more metabolically efficient. To our knowledge this is the first time this type of intraspecific variation in mitochondrial respiration has been measured in wild birds and we discuss how such mitochondrial adaptations may have facilitated introgression. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

  13. Tracking Seasonal Habitats Using Carbon and Nitrogen Stable Isotopes of Osprey Primary Flight Feathers

    Science.gov (United States)

    Velinsky, D.; Zelanko, P.; Rice, N.

    2011-12-01

    The majority of bird migration studies use the latitudinal precipitation effect of hydrogen and oxygen stable isotopes of feathers to determine wintering and breeding grounds. Few studies have considered carbon and nitrogen stable isotopes to accomplish the same goal; exploiting the variation in dietary constitutes throughout yearly migration cycles. Also, there is no standard procedure of feather sampling; some use body, while others use wing feathers. This sampling discrepancy is not an issue for most migratory species since the majority of birds molt completely in one location, i.e. wintering verse breeding ground. Large birds of prey however, have a continuous molt that may last years, growing feathers on their breeding and wintering grounds. Therefore, a stable isotopic study of Osprey could not randomly sample feathers because it is impossible to know where individual feathers were grown. Here we present an in depth study of carbon and nitrogen stable isotopes from Mid-Atlantic Osprey primary flight feathers. Not only did we observe three signatures indicating the breeding ground and two distinct wintering grounds, we recorded dietary seasonality shifts within 2 to 3 year olds that remain on the wintering grounds for multiple years.

  14. Exploring bird aerodynamics using radio-controlled models

    Energy Technology Data Exchange (ETDEWEB)

    Hoey, Robert G, E-mail: bobh@antelecom.ne [Air Force Flight Test Center, Edwards AFB, CA (United States)

    2010-12-15

    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.

  15. Exploring bird aerodynamics using radio-controlled models.

    Science.gov (United States)

    Hoey, Robert G

    2010-12-01

    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.

  16. Miracle Flights

    Science.gov (United States)

    ... a Flight Get Involved Events Shop Miles Contact Miracle Flights Blog Giving Tuesday 800-359-1711 Thousands of children have been saved, but we still have miles to go. Request a Flight Click Here to Donate - Your ...

  17. 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 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....

  18. Insight into the growth pattern and bone fusion of basal birds from an Early Cretaceous enantiornithine bird.

    Science.gov (United States)

    Wang, Min; Li, Zhiheng; Zhou, Zhonghe

    2017-10-24

    Bird skeletons exhibit remarkable modifications that allow for flight. The most distinguishable features are the fusion of the bones in the hand, feet, and pelvis into composite rigid and bony structures. However, the historical origins of these avian bone fusions remain elusive because of the rarity of transitional fossils and developmental studies on modern birds. Here, we describe an Early Cretaceous bird (120 Mya) that has fully fused alular-major metacarpals and pelvis. We discuss the manus and pelvis fusions across Paravian phylogeny and demonstrate that these features evolved independently across nonavian theropods, Enantiornithes, and Ornithuromorpha. The fusions of these bones are rare in known nonavian theropods and Early Cretaceous birds but are well established among Late Cretaceous and modern birds, revealing a complicated evolution pattern unrecognized previously. We posit that the developments of bone fusion were polymorphic close to the origin of birds, resulting in the varying degrees of fusion in Paraves. However, that development polymorphism appears to be fundamentally restricted along the line to modern birds by the Late Cretaceous, where all birds have a completely fused manus and pelvis. Such changes likely correspond to a refinement of flight capability. Alternatively, the degree of bone fusion in this primitive bird may have been related to modifications in genes or developmental paths. Future studies and fossil discoveries are required to clarify these hypotheses and pinpoint the developmental pathways involving the bone fusions in early avian evolution through to their modern pattern.

  19. 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.

  20. 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...

  1. 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...

  2. 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 ...

  3. Ancient DNA reveals elephant birds and kiwi are sister taxa and clarifies ratite bird evolution.

    Science.gov (United States)

    Mitchell, Kieren J; Llamas, Bastien; Soubrier, Julien; Rawlence, Nicolas J; Worthy, Trevor H; Wood, Jamie; Lee, Michael S Y; Cooper, Alan

    2014-05-23

    The evolution of the ratite birds has been widely attributed to vicariant speciation, driven by the Cretaceous breakup of the supercontinent Gondwana. The early isolation of Africa and Madagascar implies that the ostrich and extinct Madagascan elephant birds (Aepyornithidae) should be the oldest ratite lineages. We sequenced the mitochondrial genomes of two elephant birds and performed phylogenetic analyses, which revealed that these birds are the closest relatives of the New Zealand kiwi and are distant from the basal ratite lineage of ostriches. This unexpected result strongly contradicts continental vicariance and instead supports flighted dispersal in all major ratite lineages. We suggest that convergence toward gigantism and flightlessness was facilitated by early Tertiary expansion into the diurnal herbivory niche after the extinction of the dinosaurs. Copyright © 2014, American Association for the Advancement of Science.

  4. A circannual perspective on daily and total flight distances in a long-distance migratory raptor, the Montagu's harrier,Circus pygargus.

    Science.gov (United States)

    Schlaich, Almut E; Bouten, Willem; Bretagnolle, Vincent; Heldbjerg, Henning; Klaassen, Raymond H G; Sørensen, Iben H; Villers, Alexandre; Both, Christiaan

    2017-06-01

    Long-distance migrants are particularly recognized for the distances covered on migration, yet little is known about the distances they cover during the rest of the year. GPS-tracks of 29 Montagu's harriers from breeding areas in France, The Netherlands and Denmark showed that harriers fly between 35 653 and 88 049 km yr -1 , of which on average only 28.5% is on migration. Mean daily distances during migration were 296 km d -1 in autumn and 252 km d -1 in spring. Surprisingly, males' daily distances during breeding (217 km d -1 ) were close to those during migration, whereas breeding females moved significantly less (101 km d -1 ) than males. In terms of flight distance, the breeding season seemed nearly as demanding as migration periods for males. During the six winter months, both sexes moved less (114 and 128 km d -1 for females and males, respectively) than during migration. Harriers therefore covered shorter daily distances during winter which might allow birds to compensate for the more demanding phases of migration and breeding. © 2017 The Author(s).

  5. Abundância sazonal de aves migratórias na Área de Proteção Ambiental de Piaçabuçu, Alagoas, Brasil Seasonal abundance of migratory birds in the Piaçabuçu Protection Area, Alagoas, Brazil

    Directory of Open Access Journals (Sweden)

    Susanna A. S. Cabral

    2006-09-01

    Full Text Available Todos os anos milhares de aves limícolas e migratórias invernam ao longo da costa da América do Sul, entre setembro e abril, onde adquirem massa corpórea e realizam mudas para retornar aos sítios de reprodução. Estudos quali-quantitativos foram realizados na Área de Proteção Ambiental de Piaçabuçu, Alagoas, Brasil, através da contagem direta, objetivando o acompanhamento das flutuações sazonais da avifauna migrante. Foram registradas cinco espécies da família Charadriidae: Vanellus chilensis (Wagler, 1827; Pluvialis squatarola (Linnaeus, 1758; Charadrius semipalmatus Bonaparte, 1825; Charadrius collaris Vieillot, 1818 e Charadrius wilsonia (Ord, 1814 e cinco espécies da família Scolopacidae: Arenaria interpres (Linnaeus, 1758; Actitis macularius (Linnaeus, 1766; Catoptrophorus semipalmatus (Gmelin, 1789; Calidris pusilla (Linnaeus, 1766 e Calidris alba (Pallas, 1764. Pluvialis squatarola, Charadrius semipalmatus, Charadrius collaris, Arenaria interpres, Calidris pusilla e Calidris alba foram consideradas constantes (presentes em mais de 50% das observações. Charadrius semipalmatus e Calidris alba apresentaram os maiores índices de freqüência de ocorrência nos meses de novembro e dezembro e, março e setembro, respectivamente. A correlação de Spearman demonstra uma forte dependência na migração destas espécies. A fidelidade dessas aves a APA de Piaçabuçu observada nessa pesquisa indica ser a área um sítio de invernada, reforçando sua importância para a conservação das espécies migratórias que utilizam o local.Every year, thousands of limicola and migratory birds winter on the South American coast, between September and April, where they acquire body mass and undergo moulting before returning to their reproduction sites. Qualitative and quantitative studies were performed in the Piaçabuçu Protection Area located in the state of Alagoas, Brazil, by direct counting, aiming to follow upon the birds' seasonal

  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. 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.

  8. Preadaptive Stage for Flight Origin

    Directory of Open Access Journals (Sweden)

    Bogdanovich I. A.

    2017-04-01

    Full Text Available Bipedalism as a preadaptive stage for bird’s flight is considered. We attribute the formation of full bipedalism in bird ancestors with pelvic limbs transition from segmental to parasagittal position. This transition was fast enough. We can assume that the pectoral limbs freed from the support remained while laterally spaced and gave set of transformations with different degrees of reduction. Thus morphologically “winglike” version of the thoracic limbs could appear. Parasagittal pelvic limbs allowed birds ancestors fast and maneuverable running, while the movements of free and highly movable thoracic limbs (feathered unrelated to flight provided dynamic stability of the animal. In addition, their fluttering movements facilitate hopping from one branch to another and the descent from the trees. On the bottom branches protobirds could jump with perching just by the pelvic anisodactyl limbs, not by thoracic as had supposed earlier. Active interaction of the primary simple feathers with air as well as its protective function could become an impetus for their transformation into differentiated structures. Unlike gliding (as preadaptive stage for active flight bipedalism with free feathered forelimbs provides per se parallel development of two autonomous enough locomotor systems of birds (flight and terrestrial locomotion and extensive adaptive radiation of representatives of the class.

  9. Biogeographical Profiles of Shorebird Migration in Midcontinental North America

    National Research Council Canada - National Science Library

    Skagen, Susan

    1999-01-01

    .... Because of the tremendous energy demands of these long distance migratory flights, stopover habitats and resources for rest and refueling are critical to the survival and successful reproduction of this group of birds...

  10. 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.

  11. 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

  12. Gendering Migration

    Directory of Open Access Journals (Sweden)

    Mirjana Morokvašić

    2014-12-01

    Full Text Available Migration patterns, migration discourse and underlying representations, migrants’ experiences, obligations and duties as well as the expectations relative to their migration are gendered. Since the pioneering feminist migration scholars’ questioning of men as a universal reference and the invisibility of women or their stereotypical representations as dependents in the mainstream production of knowledge on migration, the scholarship has evolved considerably. It is argued in the paper that the ongoing process of cross-fertilization of developments in two separate epistemologies, each initially questioning monolithic and essentialist visions of a “migrant” on one hand and a “woman” on the other, produced a fecund subfield of research “migration and gender”. The paper provides an insight into this, reviewing work on the issues related to gendering different phases of migration. Bridging migration and gender brought to the top of research agendas issues that used to be on the margins, creating new visibilities but leaving out other gendered dimensions of complex realities of migrant experience.

  13. Modeling the distribution of migratory bird stopovers to inform landscape-scale siting of wind development.

    Science.gov (United States)

    Pocewicz, Amy; Estes-Zumpf, Wendy A; Andersen, Mark D; Copeland, Holly E; Keinath, Douglas A; Griscom, Hannah R

    2013-01-01

    Conservation of migratory birds requires understanding the distribution of and potential threats to their migratory habitats. However, although migratory birds are protected under international treaties, few maps have been available to represent migration at a landscape scale useful to target conservation efforts or inform the siting of wind energy developments that may affect migratory birds. To fill this gap, we developed models that predict where four groups of birds concentrate or stopover during their migration through the state of Wyoming, USA: raptors, wetland, riparian and sparse grassland birds. The models were based on existing literature and expert knowledge concerning bird migration behavior and ecology and validated using expert ratings and known occurrences. There was significant agreement between migratory occurrence data and migration models for all groups except raptors, and all models ranked well with experts. We measured the overlap between the migration concentration models and a predictive model of wind energy development to assess the potential exposure of migratory birds to wind development and illustrate the utility of migratory concentration models for landscape-scale planning. Wind development potential is high across 15% of Wyoming, and 73% of this high potential area intersects important migration concentration areas. From 5.2% to 18.8% of each group's important migration areas was represented within this high wind potential area, with the highest exposures for sparse grassland birds and the lowest for riparian birds. Our approach could be replicated elsewhere to fill critical data gaps and better inform conservation priorities and landscape-scale planning for migratory birds.

  14. Modeling the distribution of migratory bird stopovers to inform landscape-scale siting of wind development.

    Directory of Open Access Journals (Sweden)

    Amy Pocewicz

    Full Text Available Conservation of migratory birds requires understanding the distribution of and potential threats to their migratory habitats. However, although migratory birds are protected under international treaties, few maps have been available to represent migration at a landscape scale useful to target conservation efforts or inform the siting of wind energy developments that may affect migratory birds. To fill this gap, we developed models that predict where four groups of birds concentrate or stopover during their migration through the state of Wyoming, USA: raptors, wetland, riparian and sparse grassland birds. The models were based on existing literature and expert knowledge concerning bird migration behavior and ecology and validated using expert ratings and known occurrences. There was significant agreement between migratory occurrence data and migration models for all groups except raptors, and all models ranked well with experts. We measured the overlap between the migration concentration models and a predictive model of wind energy development to assess the potential exposure of migratory birds to wind development and illustrate the utility of migratory concentration models for landscape-scale planning. Wind development potential is high across 15% of Wyoming, and 73% of this high potential area intersects important migration concentration areas. From 5.2% to 18.8% of each group's important migration areas was represented within this high wind potential area, with the highest exposures for sparse grassland birds