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Sample records for strix varia habitat

  1. Using detection dogs to conduct simultaneous surveys of northern spotted (Strix occidentalis caurina and barred owls (Strix varia.

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    Samuel K Wasser

    Full Text Available State and federal actions to conserve northern spotted owl (Strix occidentalis caurina habitat are largely initiated by establishing habitat occupancy. Northern spotted owl occupancy is typically assessed by eliciting their response to simulated conspecific vocalizations. However, proximity of barred owls (Strix varia-a significant threat to northern spotted owls-can suppress northern spotted owl responsiveness to vocalization surveys and hence their probability of detection. We developed a survey method to simultaneously detect both species that does not require vocalization. Detection dogs (Canis familiaris located owl pellets accumulated under roost sites, within search areas selected using habitat association maps. We compared success of detection dog surveys to vocalization surveys slightly modified from the U.S. Fish and Wildlife Service's Draft 2010 Survey Protocol. Seventeen 2 km × 2 km polygons were each surveyed multiple times in an area where northern spotted owls were known to nest prior to 1997 and barred owl density was thought to be low. Mitochondrial DNA was used to confirm species from pellets detected by dogs. Spotted owl and barred owl detection probabilities were significantly higher for dog than vocalization surveys. For spotted owls, this difference increased with number of site visits. Cumulative detection probabilities of northern spotted owls were 29% after session 1, 62% after session 2, and 87% after session 3 for dog surveys, compared to 25% after session 1, increasing to 59% by session 6 for vocalization surveys. Mean detection probability for barred owls was 20.1% for dog surveys and 7.3% for vocal surveys. Results suggest that detection dog surveys can complement vocalization surveys by providing a reliable method for establishing occupancy of both northern spotted and barred owl without requiring owl vocalization. This helps meet objectives of Recovery Actions 24 and 25 of the Revised Recovery Plan for the

  2. Northern Spotted Owl (Strix occidentalis caurina) Genome: Divergence with the Barred Owl (Strix varia) and Characterization of Light-Associated Genes.

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    Hanna, Zachary R; Henderson, James B; Wall, Jeffrey D; Emerling, Christopher A; Fuchs, Jérôme; Runckel, Charles; Mindell, David P; Bowie, Rauri C K; DeRisi, Joseph L; Dumbacher, John P

    2017-10-01

    We report here the assembly of a northern spotted owl (Strix occidentalis caurina) genome. We generated Illumina paired-end sequence data at 90× coverage using nine libraries with insert lengths ranging from ∼250 to 9,600 nt and read lengths from 100 to 375 nt. The genome assembly is comprised of 8,108 scaffolds totaling 1.26 × 109 nt in length with an N50 length of 3.98 × 106 nt. We calculated the genome-wide fixation index (FST) of S. o. caurina with the closely related barred owl (Strix varia) as 0.819. We examined 19 genes that encode proteins with light-dependent functions in our genome assembly as well as in that of the barn owl (Tyto alba). We present genomic evidence for loss of three of these in S. o. caurina and four in T. alba. We suggest that most light-associated gene functions have been maintained in owls and their loss has not proceeded to the same extent as in other dim-light-adapted vertebrates. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  3. Barred Owl Habitat and Prey: A Review and Synthesis of the Literature

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    Livezey, Kent B.

    2007-01-01

    Barred Owls (Strix varia) historically inhabited the forests of eastern North America. During the last century, they expanded their range to include forests throughout the southern provinces of Canada, southeastern Alaska, British Columbia, Washington, Oregon, and northern California. To date, there has been no synthesis of the varied habitats or prey used by Barred Owls in their expanded range. Here I review and synthesize studies concerning habitat (N  =  114) and prey (N  =  43) of Barred ...

  4. Determination of Gastrointestinal Transit Times in Barred Owls ( Strix varia ) by Contrast Fluoroscopy.

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    Doss, Grayson A; Williams, Jackie M; Mans, Christoph

    2017-06-01

    Contrast imaging studies are routinely performed in avian patients when an underlying abnormality of the gastrointestinal (GI) tract is suspected. Fluoroscopy offers several advantages over traditional radiography and can be performed in conscious animals with minimal stress and restraint. Although birds of prey are commonly encountered as patients, little is known about GI transit times and contrast imaging studies in these species, especially owls. Owls are commonly encountered in zoological, educational, and wildlife settings. In this study, 12 adult barred owls ( Strix varia ) were gavage fed a 30% weight-by-volume barium suspension (25 mL/kg body weight). Fluoroscopic exposures were recorded at 5, 15, 30, 60, 120, 180, 240, and 300 minutes after administration. Overall GI transit time and transit times of various GI organs were recorded. Median (interquartile range [IQR]) overall GI transit time was 60 minutes (IQR: 19-60 minutes) and ranged from 5-120 minutes. Ventricular and small intestinal contrast filling was rapid. Ventricular emptying was complete by a median of 60 minutes (IQR: 30-120 minutes; range: 30-240 minutes), whereas small intestinal emptying was not complete in 9/12 birds by 300 minutes. Median small intestinal contraction rate was 15 per minute (IQR: 13-16 minutes; range: 10-19 minutes). Median overall GI transit time in barred owls is more rapid than mean transit times reported for psittacine birds and red-tailed hawks ( Buteo jamaicensis ). Fluoroscopy is a safe, suitable method for investigating GI motility and transit in this species.

  5. California Spotted Owl (Strix occidentalis occidentalis) habitat use patterns in a burned landscape

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    Eyes, Stephanie; Roberts, Susan L.; Johnson, Matthew D.

    2017-01-01

    Fire is a dynamic ecosystem process of mixed-conifer forests of the Sierra Nevada, but there is limited scientific information addressing wildlife habitat use in burned landscapes. Recent studies have presented contradictory information regarding the effects of stand-replacing wildfires on Spotted Owls (Strix occidentalis) and their habitat. While fire promotes heterogeneous forest landscapes shown to be favored by owls, high severity fire may create large canopy gaps that can fragment the closed-canopy habitat preferred by Spotted Owls. We used radio-telemetry to determine whether foraging California Spotted Owls (S. o. occidentalis) in Yosemite National Park, California, USA, showed selection for particular fire severity patch types within their home ranges. Our results suggested that Spotted Owls exhibited strong habitat selection within their home ranges for locations near the roost and edge habitats, and weak selection for lower fire severity patch types. Although owls selected high contrast edges with greater relative probabilities than low contrast edges, we did not detect a statistical difference between these probabilities. Protecting forests from stand-replacing fires via mechanical thinning or prescribed fire is a priority for management agencies, and our results suggest that fires of low to moderate severity can create habitat conditions within California Spotted Owls' home ranges that are favored for foraging.

  6. Radiographic evaluation of perching-joint angles in cockatiels (Nymphicus hollandicus), Hispaniolan Amazon parrots (Amazona ventralis), and barred owls (Strix varia).

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    Bonin, Glen; Lauer, Susanne K; Guzman, David Sanchez-Migallon; Nevarez, Javier; Tully, Thomas N; Hosgood, Giselle; Gaschen, Lorrie

    2009-06-01

    Information on perching-joint angles in birds is limited. Joint immobilization in a physiologic perching angle has the potential to result more often in complete restoration of limb function. We evaluated perching-joint angles in 10 healthy cockatiels (Nymphicus hollandicus), 10 Hispaniolan Amazons (Amazona ventralis), and 9 barred owls (Strix varia) and determined intra- and interobserver variability for goniometric measurements in 2 different radiographic projections. Intra- and interobserver variation was less than 7% for all stifle and intertarsal joint measurements but frequently exceeded 10% for the hip-joint measurements. Hip, stifle, and intertarsal perching angles differed significantly among cockatiels, Hispaniolan Amazon parrots, and barred owls. The accuracy of measurements performed on straight lateral radiographic projections with superimposed limbs was not consistently superior to measurements on oblique projections with a slightly rotated pelvis. Stifle and intertarsal joint angles can be measured on radiographs by different observers with acceptable variability, but intra- and interobserver variability for hip-joint-angle measurements is higher.

  7. Meta-analysis of California Spotted Owl (Strix occidentalis occidentalis) territory occupancy in the Sierra Nevada: habitat associations and their implications for forest management

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    Douglas J. Tempel; John J. Keane; R. J. Gutierrez; Jared D. Wolfe; Gavin M. Jones; Alexander Koltunov; Carlos M. Ramirez; William J. Berigan; Claire V. Gallagher; Thomas E. Munton; Paula A. Shaklee; Sheila A. Whitmore; M. Zachariah Peery

    2016-01-01

    We assessed the occupancy dynamics of 275 California Spotted Owl (Strix occidentalis occidentalis) territories in 4 study areas in the Sierra Nevada, California, USA, from 1993 to 2011. We used Landsat data to develop maps of canopy cover for each study area, which we then used to quantify annual territory-specific habitat...

  8. Relative effects of road risk, habitat suitability, and connectivity on wildlife roadkills: the case of tawny owls (Strix aluco).

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    Santos, Sara M; Lourenço, Rui; Mira, António; Beja, Pedro

    2013-01-01

    Despite its importance for reducing wildlife-vehicle collisions, there is still incomplete understanding of factors responsible for high road mortality. In particular, few empirical studies examined the idea that spatial variation in roadkills is influenced by a complex interplay between road-related factors, and species-specific habitat quality and landscape connectivity. In this study we addressed this issue, using a 7-year dataset of tawny owl (Strix aluco) roadkills recorded along 37 km of road in southern Portugal. We used a multi-species roadkill index as a surrogate of intrinsic road risk, and we used a Maxent distribution model to estimate habitat suitability. Landscape connectivity was estimated from least-cost paths between tawny owl territories, using habitat suitability as a resistance surface. We defined 10 alternative scenarios to compute connectivity, based on variation in potential movement patterns according to territory quality and dispersal distance thresholds. Hierarchical partitioning of a regression model indicated that independent variation in tawny owl roadkills was explained primarily by the roadkill index (70.5%) and, to a much lesser extent, by landscape connectivity (26.2%), while habitat suitability had minor effects (3.3%). Analysis of connectivity scenarios suggested that owl roadkills were primarily related to short range movements (habitat quality and landscape connectivity are globally high for the study species. Nevertheless, the study supported the view that functional connectivity should be incorporated whenever possible in roadkill models, as it may greatly increase their power to predict the location of roadkill hotspots.

  9. The evolution of mapping habitat for northern spotted owls (Strix occidentalis caurina): A comparison of photo-interpreted, Landsat-based, and lidar-based habitat maps

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    Ackers, Steven H.; Davis, Raymond J.; Olsen, K.; Dugger, Catherine

    2015-01-01

    Wildlife habitat mapping has evolved at a rapid pace over the last few decades. Beginning with simple, often subjective, hand-drawn maps, habitat mapping now involves complex species distribution models (SDMs) using mapped predictor variables derived from remotely sensed data. For species that inhabit large geographic areas, remote sensing technology is often essential for producing range wide maps. Habitat monitoring for northern spotted owls (Strix occidentalis caurina), whose geographic covers about 23 million ha, is based on SDMs that use Landsat Thematic Mapper imagery to create forest vegetation data layers using gradient nearest neighbor (GNN) methods. Vegetation data layers derived from GNN are modeled relationships between forest inventory plot data, climate and topographic data, and the spectral signatures acquired by the satellite. When used as predictor variables for SDMs, there is some transference of the GNN modeling error to the final habitat map.Recent increases in the use of light detection and ranging (lidar) data, coupled with the need to produce spatially accurate and detailed forest vegetation maps have spurred interest in its use for SDMs and habitat mapping. Instead of modeling predictor variables from remotely sensed spectral data, lidar provides direct measurements of vegetation height for use in SDMs. We expect a SDM habitat map produced from directly measured predictor variables to be more accurate than one produced from modeled predictors.We used maximum entropy (Maxent) SDM modeling software to compare predictive performance and estimates of habitat area between Landsat-based and lidar-based northern spotted owl SDMs and habitat maps. We explored the differences and similarities between these maps, and to a pre-existing aerial photo-interpreted habitat map produced by local wildlife biologists. The lidar-based map had the highest predictive performance based on 10 bootstrapped replicate models (AUC = 0.809 ± 0.011), but the

  10. Blood parasites in Owls with conservation implications for the Spotted Owl (Strix occidentalis)

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    Ishak, H.D.; Dumbacher, J.P.; Anderson, N.L.; Keane, J.J.; Valkiunas, G.; Haig, S.M.; Tell, L.A.; Sehgal, R.N.M.

    2008-01-01

    The three subspecies of Spotted Owl (Northern, Strix occidentalis courina; California, S. o. occidentalis; and Mexican, S. o. lucida) are all threatened by habitat loss and range expansion of the Barred Owl (S. varia). An unaddressed threat is whether Barred Owls could be a source of novel strains of disease such as avian malaria (Plasmodium spp.) or other blood parasites potentially harmful for Spotted Owls. Although Barred Owls commonly harbor Plasmodium infections, these parasites have not been documented in the Spotted Owl. We screened 111 Spotted Owls, 44 Barred Owls, and 387 owls of nine other species for haemosporidian parasites (Leucocytozoon, Plasmodium, and Haemoproteus spp.). California Spotted Owls had the greatest number of simultaneous multi-species infections (44%). Additionally, sequencing results revealed that the Northern and California Spotted Owl subspecies together had the highest number of Leucocytozoon parasite lineages (n=17) and unique lineages (n=12). This high level of sequence diversity is significant because only one leucocytozoon species (L. danilewskyi) has been accepted as valid among all owls, suggesting that L. danilewskyi is a cryptic species. Furthermore, a Plasmodium parasite was documented in a Northern Spotted Owl for the first time. West Coast Barred Owls had a lower prevalence of infection (15%) when compared to sympatric Spotted Owls (S. o. caurina 52%, S. o. occidentalis 79%) and Barred Owls from the historic range (61%). Consequently, Barred Owls on the West Coast may have a competitive advantage over the potentially immune compromised Spotted Owls. ?? 2008 Ishak et al.

  11. Comparative food niche analysis of Strix Owls in Belarus

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    Alexey K. Tishechkin

    1997-01-01

    Three Strix species breed sympatrically in Belarus. The Tawny Owl (Strix aluco) is one of two commonest owl species in the country, and is distributed throughout the whole territory. Its' range overlaps widely with two other species, the Ural Owl (S. uralensis) which is common in the forests of the northern part and the Great...

  12. Modeling demographic performance of northern spotted owls relative to forest habitat in Oregon

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    Olson, Gail S.; Glenn, Elizabeth M.; Anthony, Robert G.; Forsman, Eric D.; Reid, Janice A.; Loschl, Peter J.; Ripple, William J.

    2004-01-01

    Northern spotted owls (Strix occidentalis caurina) are known to be associated with late-successional forests in the Pacific Northwest of the United States, but the effects of habitat on their demographic performance are relatively unknown. We developed statistical models relating owl survival and productivity to forest cover types within the Roseburg Study Area in the Oregon Coast Range of Oregon, USA. We further combined these demographic parameters using a Leslie-type matrix to obtain an estimate of habitat fitness potential for each owl territory (n = 94). We used mark–recapture methods to develop models for survival and linear mixed models for productivity. We measured forest composition and landscape patterns at 3 landscape scales centered on nest and activity sites within owl territories using an aerial photo-based map and a Geographic Information System (GIS). We also considered additional covariates such as age, sex, and presence of barred owls (Strix varia), and seasonal climate variables (temperature and precipitation) in our models. We used Akaike's Information Criterion (AIC) to rank and compare models. Survival had a quadratic relationship with the amount of late- and mid-seral forests within 1,500 m of nesting centers. Survival also was influenced by the amount of precipitation during the nesting season. Only 16% of the variability in survival was accounted for by our best model, but 85% of this was due to the habitat variable. Reproductive rates fluctuated biennially and were positively related to the amount of edge between late- and mid-seral forests and other habitat classes. Reproductive rates also were influenced by parent age, amount of precipitation during nesting season, and presence of barred owls. Our best model accounted for 84% of the variability in productivity, but only 3% of that was due to the habitat variable. Estimates of habitat fitness potential (which may range from 0 to infinity) for the 94 territories ranged from 0.74 to 1

  13. The roles of competition and habitat in the dynamics of populations and species distributions

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    Yackulic, Charles Brandon; Reid, Janice; Nichols, James D.; Hines, James E.; Davis, Raymond; Forsman, Eric

    2014-01-01

    The role of competition in structuring biotic communities at fine spatial scales is well known from detailed process-based studies. Our understanding of competition's importance at broader scales is less resolved and mainly based on static species distribution maps. Here, we bridge this gap by examining the joint occupancy dynamics of an invading (barred owl: Strix varia) and a resident species (Northern spotted owl: Strix occidentalis caurina) in a 1000 km2 study area over a 22 - year period. Past studies of these competitors have focused on the dynamics of one species at a time, hindering efforts to parse out the roles of habitat and competition and to forecast the future of the resident species. In addition, while these studies accounted for the imperfect detection of the focal species, no multiseason analysis of these species has accounted for the imperfect detection of the secondary species, potentially biasing inference. We analyze survey data using models that combine the general multistate-multiseason occupancy modeling framework with autologistic modeling - allowing us to account for important aspects of our study system. We find that local extinction probability increases for each species when the other is present; however, the effect of the invader on the resident is greater. Although the species prefer different habitats, these habitats are highly correlated at the patch scale and the impacts of invader on the resident are greatest in patches that would otherwise be optimal. As a consequence, competition leads to a weaker relationship between habitat and Northern spotted owl occupancy. Colonization and extinction rates of the invader are closely related to neighborhood occupancy, and over the first half of the study the availability of colonists limited the rate of population growth. Competition is likely to exclude the resident species both through its immediate effects on local extinction, and by indirectly lowering colonization rates as Northern

  14. The roles of competition and habitat in the dynamics of populations and species distributions.

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    Yackulic, Charles B; Reid, Janice; Nichols, James D; Hines, James E; Davis, Raymond; Forsman, Eric

    2014-02-01

    The role of competition in structuring biotic communities at fine spatial scales is well known from detailed process-based studies. Our understanding of competition's importance at broader scales is less resolved and mainly based on static species distribution maps. Here, we bridge this gap by examining the joint occupancy dynamics of an invading species (Barred Owl, Strix varia) and a resident species (Northern Spotted Owl, Strix occidentalis caurina) in a 1000-km study area over a 22-year period. Past studies of these competitors have focused on the dynamics of one species at a time, hindering efforts to parse out the roles of habitat and competition and to forecast the future of the resident species. In addition, while these studies accounted for the imperfect detection of the focal species, no multi-season analysis of these species has accounted for the imperfect detection of the secondary species, potentially biasing inference. We analyzed survey data using models that combine the general multistate-multi-season occupancy modeling framework with autologistic modeling, allowing us to account for important aspects of our study system. We found that local extinction probability increases for each species when the other is present; however, the effect of the invader on the resident is greater. Although the species prefer different habitats, these habitats are highly correlated at the patch scale, and the impacts of invader on the resident are greatest in patches that would otherwise be optimal. As a consequence, competition leads to a weaker relationship between habitat and Northern Spotted Owl occupancy. Colonization and extinction rates of the invader are closely related to neighborhood occupancy, and over the first half of the study the availability of colonists limited the rate of population growth. Competition is likely to exclude the resident species, both through its immediate effects on local extinction and by indirectly lowering colonization rates as

  15. Influence of primary prey on home-range size and habitat-use patterns of northern spotted owls (Strix occidentalis caurina)

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    Cynthia J. Zabel; Kevin S. McKelvey; James P. Ward

    1995-01-01

    Correlations between the home-range size of northern spotted owls (Strix occidentalis caurina) and proportion of their range in old-growth forest have been reported, but there are few data on the relationship between their home-range size and prey. The primary prey of spotted owls are wood rats and northern flying squirrels (Glaucomys sabrinus). Wood...

  16. The scientific basis for modeling Northern Spotted Owl habitat: A response to Loehle, Irwin, Manly, and Merrill

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    Jeffrey R. Dunk; Brian Woodbridge; Elizabeth M. Glenn; Raymond J. Davis; Katherine Fitzgerald; Paul Henson; David W. LaPlante; Bruce G. Marcot; Barry R. Noon; Martin G. Raphael; Nathan H. Schumaker; Brendan. White

    2015-01-01

    The U.S. Fish and Wildlife Service recently revised the recovery plan (USFWS, 2011) and designated Critical Habitat (USFWS, 2012a) for the Northern Spotted Owl (Strix occidentalis caurina). The Critical Habitat designation was based in part on a map of relative habitat suitability that was developed by USFWS (2011, 2012b) for this purpose. Loehle...

  17. Models for mapping potential habitat at landscape scales: an example using northern spotted owls.

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    William C. McComb; Michael T. McGrath; Thomas A. Spies; David. Vesely

    2002-01-01

    We are assessing the potential for current and alternative policies in the Oregon Coast Range to affect habitat capability for a suite of forest resources. We provide an example of a spatially explicit habitat capability model for northern spotted owls (Strix occidentalis caurina)to illustrate the approach we are taking to assess potential changes...

  18. Comparative habitat use of sympatric Mexican spotted and great horned owls

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    Joseph L. Ganey; William M. Block; Jeffrey S. Jenness; Randolph A. Wilson

    1997-01-01

    To provide information on comparative habitat use, we studied radiotagged Mexican spotted owls (Strix occidentalis lucida: n = 13) and great horned owls (Bubo virginianus: n = 4) in northern Arizona. Home-range size (95% adaptive kernel estimate) did not differ significantly between species during either the breeding or nonbreeding...

  19. Application of Bayesian methods to habitat selection modeling of the northern spotted owl in California: new statistical methods for wildlife research

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    Howard B. Stauffer; Cynthia J. Zabel; Jeffrey R. Dunk

    2005-01-01

    We compared a set of competing logistic regression habitat selection models for Northern Spotted Owls (Strix occidentalis caurina) in California. The habitat selection models were estimated, compared, evaluated, and tested using multiple sample datasets collected on federal forestlands in northern California. We used Bayesian methods in interpreting...

  20. Great gray owls (Strix nebulosa) in Yosemite National Park: on the importance of food, forest structure, and human disturbance

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    van Riper, Charles; Fontaine, Joseph J.; van Wagtendonk, Jan W.

    2013-01-01

    We studied great gray owls (Strix nebulosa Forster) in Yosemite National Park, California, measuring variables that could potentially influence patterns of occurrence and conservation of this stateendangered species. We found that owl presence was closely tied to habitat (red fir (Abies magnified A. Murray) and the abundance of meadows), prey, and snags across the landscape. We also found that indicators of human recreational activities negatively influenced owl distribution and habitat use. Great gray owls appear to prefer mid-elevation red fir forest with meadows that are drier and more productive in terms of small mammal populations. That these areas also have the highest human activity presents a paradox, both for individual owls and for the future conservation and management of this California endangered species. The extent to which human recreation in natural areas affects animal behavior, species distribution, and productivity is a growing issue in natural area management. We present information that will allow land managers to better understand how existing natural resources, coupled with human recreation, influence the distribution and habitat use of the great gray owl.

  1. Registro del búho leonado Strix fulvescens en el estado de Oaxaca, México Record of the Fulvous Owl Strix fulvescens in the state of Oaxaca, Mexico

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    Ricarda Ramírez-Julián

    2011-06-01

    Full Text Available Mediante comparaciones acústicas y espectrográficas del búho leonado Strix fulvescens, se determinó su presencia en el noroeste de la sierra Norte de Oaxaca. Este registro constituye la confirmación de su presencia en el estado; amplía 350 km aproximadamente su distribución hacia el noroeste y aumenta a 21 las especies de búhos registradas en Oaxaca.The occurrence of Fulvous Owl Strix fulvescens in the northwestern portion of the Sierra Norte of Oaxaca was determined using aural and spectrographic comparison. This record confirms the presence of Fulvous Owl in the state of Oaxaca, expanding its distribution range to the northwest by about 350 Km, and increasing to 21 species the number of owls recorded in Oaxaca.

  2. The contribution of federal and nonfederal habitat to persistence of the northern spotted owl on the Olympic Peninsula, Washington: report of the reanalysis team.

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    Richard S. Holthausen; Martin G. Raphael; Kevin S. McKelvey; Eric D. Forsman; Edward E. Starkey; D. Erran. Seaman

    1995-01-01

    We analyzed likely patterns of distribution and persistence of northern spotted owls (Strix occidentalis caurina) on the Olympic Peninsula. Analysis focused on the effects of Federal habitat under provisions of the Northwest Forest Plan; additional benefits to the owl population of different levels of habitat retention on non-Federal lands; effects of establishing a...

  3. Neighborhood and habitat effects on vital rates: expansion of the Barred Owl in the Oregon Coast Ranges

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    Yackulic, Charles B.; Reid, Janice; Davis, Raymond; Hines, James E.; Nichols, James D.; Forsman, Eric

    2012-01-01

    In this paper, we modify dynamic occupancy models developed for detection-nondetection data to allow for the dependence of local vital rates on neighborhood occupancy, where neighborhood is defined very flexibly. Such dependence of occupancy dynamics on the status of a relevant neighborhood is pervasive, yet frequently ignored. Our framework permits joint inference about the importance of neighborhood effects and habitat covariates in determining colonization and extinction rates. Our specific motivation is the recent expansion of the Barred Owl (Strix varia) in western Oregon, USA, over the period 1990-2010. Because the focal period was one of dramatic range expansion and local population increase, the use of models that incorporate regional occupancy (sources of colonists) as determinants of dynamic rate parameters is especially appropriate. We began our analysis of 21 years of Barred Owl presence/nondetection data in the Tyee Density Study Area (TDSA) by testing a suite of six models that varied only in the covariates included in the modeling of detection probability. We then tested whether models that used regional occupancy as a covariate for colonization and extinction outperformed models with constant or year-specific colonization or extinction rates. Finally we tested whether habitat covariates improved the AIC of our models, focusing on which habitat covariates performed best, and whether the signs of habitat effects are consistent with a priori hypotheses. We conclude that all covariates used to model detection probability lead to improved AIC, that regional occupancy influences colonization and extinction rates, and that habitat plays an important role in determining extinction and colonization rates. As occupancy increases from low levels toward equilibrium, colonization increases and extinction decreases, presumably because there are more and more dispersing juveniles. While both rates are affected, colonization increases more than extinction decreases

  4. Effects of experimental removal of barred owls on population demography of northern spotted owls in Washington and Oregon—2015 progress report

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    Wiens, J. David; Dugger, Katie M.; Lewicki, Krista E.; Simon, David C.

    2016-03-14

    Evidence indicates that competition with newly established barred owls (Strix varia) is causing rapid declines in populations of northern spotted owls (Strix occidentalis caurina), and that the longterm persistence of spotted owls may be in question without additional management intervention. A pilot study in California showed that lethal removal of barred owls in combination with habitat conservation may be able to slow or even reverse population declines of spotted owls at local scales, but it remains unknown whether similar results can be obtained in larger areas with different forest conditions and where barred owls are more abundant. In 2015, we implemented a before-after-controlimpact (BACI) experimental design on two study areas in Oregon and Washington with at least 20 years of pre-treatment demographic data on spotted owls to determine if removal of barred owls can improve population trends of spatially associated spotted owls. Here we provide an overview of our research accomplishments and preliminary results in Oregon and Washington in 2015.

  5. Albinism in the Great Gray Owl (Strix nebulosa) and other owls

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    Pentti Alaja; Heimo Mikkola

    1997-01-01

    An incomplete albino Great Gray Owl (Strix nebulosa) was observed in Vesanto and Kajaani, Finland, 1994-1995. The literature pertaining to albinism in owls indicates that total and incomplete albinism has only been reported in 13 different owl species, the Great Gray Owl being the only species with more than five records. Thus six to seven incomplete...

  6. Estimation of food consumption from pellets cast by captive Ural Owls (Strix uralensis)

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    Aki Higuchi; Manabu T. Abe

    1997-01-01

    There is considerable data in the literature on the diet of the Ural Owl (Strix uralensis) based on pellet analysis. Though it is possible to identify prey items by this method, the volume of food consumption is still unknown. The population of Ural Owls in Japan is declining due to the reduction of old-growth forest and the concurrent loss of...

  7. Abundance and population characteristics of Northern Spotted Owls (Strix occidentalis caurina) in Olympic National Park, Washington

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    D. Erran Seaman

    1997-01-01

    We monitored the threatened Northern Spotted Owl (Strix occidentalis caurina) in Olympic National Park from 1992 through 1996. We used a stratified random sampling scheme to survey 35 plots totaling 236 km?, approximately 10 percent of the forested area of the park.

  8. EXPLORATORY PLASMA BIOCHEMISTRY REFERENCE INTERVALS FOR URAL OWLS (STRIX URALENSIS, PALLAS 1771) FROM THE AUSTRIAN REINTRODUCTION PROJECT.

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    Scope, Alexandra; Schwendenwein, Ilse; Stanclova, Gabriela; Vobornik, Angela; Zink, Richard

    2016-06-01

    The Ural owl (Strix uralensis) is the biggest forest-living owl in Austria; however, it became extinct in Austria through poaching and habitat loss more than half a century ago. The birds examined in the present study were breeding pairs from the reintroduction project with the aim of determining exploratory plasma biochemistry reference intervals in Ural owls and evaluating the amount of biological variation between seasons, sexes, and ages. A total of 45 birds were sampled, including 13 adult males, 14 adult females, and 18 juvenile birds. Remarkably, almost all of the analytes showed significant differences between the subgroups, primarily between seasons, followed by age and sex. Only creatinkinase, glucose, lactatdehydrogenase, and triglycerides did not show any significant variations. Despite partitioning of reference values into subgroups according to biological variation diminishing the number of reference individuals in the respective groups, the resulting smaller reference intervals will improve medical assessment. The results of the present study once again demonstrate that significant seasonal fluctuations must be expected and considered in the interpretation. It can be assumed that these differences are probably even greater in free-range birds with considerable changes in food quantity and quality during and between years.

  9. Tawny owl (Strix aluco) as a potential transmitter of Enterobacteriaceae epidemiologically relevant for forest service workers, nature protection service and ornithologists.

    Science.gov (United States)

    Grzywaczewski, Grzegorz; Kowalczyk-Pecka, Danuta; Cios, Szymon; Bojar, Wiktor; Jankuszew, Andrzej; Bojar, Hubert; Kolejko, Marcin

    2017-03-31

    Established taxa within the Enterobacteriaceae wereisolated from cloacal swabs of Strix aluco chicks in nest boxes located at five research sites. ChromID ESBL medium (bioMerieux) was used to select a pool of Enterobacteriaceae strains producing extended-spectrum beta-lactamases. Drug sensitivity of the chosen strains was determined from the full pool of Enterobacteriaceae to 6 chemotherapeutics of different mechanisms of action. The study evaluated the sensitivity of ESBL-synthesizing isolates to substances belonging to penicillins, cephalosporins, cephamycins, clavams, carbapenems and monobactams. Analysis of the results indicated a potential role of Strix aluco in the dissemination of epidemiologically-relevant Enterobacteriaceae, and, importantly, pose health risks to forest service workers, nature protection service and ornithologists. The results can also serve as the basis for further environmental studies.

  10. Chapter 4: Northern spotted owl habitat and populations: Status and threats

    Science.gov (United States)

    Lesmeister, Damon B.; Davis, Ramond J; Singleton, Peter H; Wiens, David

    2018-01-01

    The northern spotted owl (Strix occidentalis caurina) was listed as threatened under the Endangered Species Act in 1990 (USFWS 1990). Providing adequate amounts of suitable forest cover to sustain the subspecies was a major component of the first recovery plan for northern spotted owls (USFWS 1992) and a driver in the basic reserve design and old-forest restoration under the Northwest Forest Plan (NWFP, or Plan) (USDA and USDI 1994). The reserve design included large contiguous blocks of late-successional forest, which was expected to be sufficient to provide habitat for many interacting pairs of northern spotted owls. As such, the selection of reserves generally favored areas with the highest quality old-growth

  11. The evolution of mapping habitat for northern spotted owls (Strix occidentalis caurina): A comparison of photo-interpreted, Landsat-based, and lidar-based habitat maps

    Science.gov (United States)

    Steven H. Ackers; Raymond J. Davis; Keith A. Olsen; Katie M. Dugger

    2015-01-01

    Wildlife habitat mapping has evolved at a rapid pace over the last fewdecades. Beginning with simple, often subjective, hand-drawn maps, habitat mapping now involves complex species distribution models (SDMs) using mapped predictor variables derived from remotely sensed data. For species that inhabit large geographic areas, remote sensing technology is often...

  12. Demography of Northern Spotted Owls in southwestern Oregon

    Science.gov (United States)

    Zabel, Cynthia J.; Salmons, Susan E.; Forsman, Eric D.; DeStefano, Stephen; Raphael, Martin G.; Gutierrez, R.J.

    1996-01-01

    Northern Spotted Owls (Strix occidentalis caurina) are associated with lower elevation, commercially valuable, late-successional coniferous forests in the Pacific Northwest. Meta-analyses of demographic parameters indicate that Northern Spotted Owl populations are declining throughout their range (Anderson and Burnham 1992, Burnham et al. this volume). Recent research has attempted to determine whether management activities have affected the viability of Spotted Owl populations, and results have led to development of conservation plans for the species (Dawson et al. 1987, Thomas et al. 1990, Murphy and Noon 1992, USDI 1992, Thomas et al. 1993b).In the Recovery Plan for the Northern Spotted Owl (USDI 1992b) threats to the species were identified as small population sizes, declining populations, limited amounts of habitat, continued loss and fragmentation of habitat, geographically isolated populations, and predation and competition from other avian species. Weather and fire are natural processes that also may affect reproductive success of Spotted Owls. Weather may be a factor in the high annual variability in fecundity of Spotted Owls, as has been suggested for other predatory bird species (Newton, 1979, 1986). However, these factors have not been addressed in previous studies of Spotted Owls.Our objectives were to estimate survival, fecundity, and annual rates of population change (l) for resident, territorial female Spotted Owls at two study areas in the coastal mountains of southwestern Oregon. We tested if the amount of rainfall was correlated with reproduction of Spotted Owls. While surveying for Spotted Owls, we documented the increased presence of Barred Owls (Strix varia), a potential competitor of Spotted Owls.

  13. Food habits of the Northern Spotted Owl (Strix occidentalis caurina) at six nest sites in Washington?s east Cascades

    Science.gov (United States)

    Kenneth R. Bevis; Jo Ellen Richards; Gina M. King; Eric E. Hanson

    1997-01-01

    This paper reports on 245 pellet samples containing 479 identified prey items collected at six Northern Spotted Owl (Strix occidentalis caurina) breeding sites in the eastern portion of its range. The majority of prey (biomass) came from four species; northern flying squirrels (Glaucomys sabrinus), bushy-tailed woodrats (...

  14. Varia

    OpenAIRE

    Genesis, La Rédaction de

    2013-01-01

    La section Varia s’ouvre sur une question de grande actualité : que devient la critique génétique à l’ère de l’écriture numérique, quand les précieuses traces manuscrites auront disparu ? En exploitant de récentes publications américaines et allemandes, Jean-Louis Lebrave montre que, contrairement à toutes les craintes et grâce aux méthodes de l’informatique légale (« computer forensics »), la critique génétique a de beaux jours devant elle. Suit une présentation de la critique génétique en A...

  15. Winter habitat occurrence patterns of temperate migrant birds in Belize

    Science.gov (United States)

    Dawson, D.K.; Robbins, C.S.; Sauer, J.R.

    1992-01-01

    We used mist nets and point counts to sample bird populations in 61 sites in Belize during January-March of 1987-1991. Sites were classified as forest, second growth, woody agricultural crops (citrus, mango, cacao, and cashew), or non-woody agricultural crops (rice and sugar cane). We evaluated patterns of occurence of wintering temperate migrant bird species in these habitats. Mist net captures of 22 of 31 migrant species differed significantly among habitats. Of these, 13 species were captured more frequently in the agricultural habitats. American Redstart (Setophaga ruticilla), Black-and-white Warbler (Mniotilta varia), and Magnolia Warbler (Dendroica magnolia) were among the species captured most frequently in woody agricultural habitats; captures of Common Yellowthroat (Geothlypis trichas), Indigo Bunting (Passerina cyanea), and Northern (lcterus galbula) and Orchard orioles (I. spur/anus) were highest in the non-woody agricultural sites. We relate these occurrence patterns to trends in breeding populations in North America. While count data provide a wide picture of winter habitat distribution of migrants, more intensive work is necessary to assess temporal and geographic variation of migrant bird use of agricultural habitats.

  16. A telemetry study of the social organization of a tawny owl (Strix aluco) population

    DEFF Research Database (Denmark)

    Sunde, Peter; Bølstad, Mikkel S.

    2004-01-01

    The spatial dispersion and social interactions were studied in 11 neighbouring pairs of radio-tagged tawny owls Strix aluco in a deciduous wood in Denmark from 1998-2001. The numbers and shapes of territories were stable throughout the survey and similar to a mapping made 40 years earlier. The home...... involving one owl only from each pair. The dispute rate between neighbouring pairs correlated positively with home-range overlap. The total annual mortality was 21% (95% CI: 6-33%). Dead owners were usually replaced within 1-2 months. Two out of four cases of radio-tagged owls disappearing from...

  17. The effects of habitat, climate, and Barred Owls on long-term demography of Northern Spotted Owls

    Science.gov (United States)

    Dugger, Catherine; Forsman, Eric D.; Franklin, Alan B.; Davis, Raymond J.; White, Gary C.; Schwarz, Carl J.; Burnham, Kenneth P.; Nichols, James D.; Hines, James E.; Yackulic, Charles B.; Doherty, Paul F.; Bailey, Larissa; Clark, Darren A.; Ackers, Steven H.; Andrews, Lawrence S.; Augustine, Benjamin; Biswell, Brian L.; Blakesley, Jennifer; Carlson, Peter C.; Clement, Matthew J.; Diller, Lowell V.; Glenn, Elizabeth M.; Green, Adam; Gremel, Scott A.; Herter, Dale R.; Higley, J. Mark; Hobson, Jeremy; Horn, Rob B.; Huyvaert, Kathryn P.; McCafferty, Christopher; McDonald, Trent; McDonnell, Kevin; Olson, Gail S.; Reid, Janice A.; Rockweit, Jeremy; Ruiz, Viviana; Saenz, Jessica; Sovern, Stan G.

    2016-01-01

    Estimates of species' vital rates and an understanding of the factors affecting those parameters over time and space can provide crucial information for management and conservation. We used mark–recapture, reproductive output, and territory occupancy data collected during 1985–2013 to evaluate population processes of Northern Spotted Owls (Strix occidentalis caurina) in 11 study areas in Washington, Oregon, and northern California, USA. We estimated apparent survival, fecundity, recruitment, rate of population change, and local extinction and colonization rates, and investigated relationships between these parameters and the amount of suitable habitat, local and regional variation in meteorological conditions, and competition with Barred Owls (Strix varia). Data were analyzed for each area separately and in a meta-analysis of all areas combined, following a strict protocol for data collection, preparation, and analysis. We used mixed effects linear models for analyses of fecundity, Cormack-Jolly-Seber open population models for analyses of apparent annual survival (ϕ), and a reparameterization of the Jolly-Seber capture–recapture model (i.e. reverse Jolly-Seber; RJS) to estimate annual rates of population change (λRJS) and recruitment. We also modeled territory occupancy dynamics of Northern Spotted Owls and Barred Owls in each study area using 2-species occupancy models. Estimated mean annual rates of population change (λ) suggested that Spotted Owl populations declined from 1.2% to 8.4% per year depending on the study area. The weighted mean estimate of λ for all study areas was 0.962 (± 0.019 SE; 95% CI: 0.925–0.999), indicating an estimated range-wide decline of 3.8% per year from 1985 to 2013. Variation in recruitment rates across the range of the Spotted Owl was best explained by an interaction between total winter precipitation and mean minimum winter temperature. Thus, recruitment rates were highest when both total precipitation (29 cm) and

  18. Multi-scale Mexican spotted owl (Strix occidentalis lucida) nest/roost habitat selection in Arizona and a comparison with single-scale modeling results

    Science.gov (United States)

    Brad C. Timm; Kevin McGarigal; Samuel A. Cushman; Joseph L. Ganey

    2016-01-01

    Efficacy of future habitat selection studies will benefit by taking a multi-scale approach. In addition to potentially providing increased explanatory power and predictive capacity, multi-scale habitat models enhance our understanding of the scales at which species respond to their environment, which is critical knowledge required to implement effective...

  19. Spotted owl roost and nest site selection in northwestern California

    Science.gov (United States)

    J.A. Blakesley; A.B. Franklin; R.J. Gutierrez

    1992-01-01

    We directly observed roost and nest site selection in a population of northern spotted owls (Strix occidentalis caurina) in northwestern California during 1985-89. Because of potential biases caused by use of radio telemetry in previous studies, we examined habitat use relative to habitat availability at a level not previously reported for spotted...

  20. Age-dependent diet change, parental care and reproductive costin tawny owls Strix aluco

    Science.gov (United States)

    Sasvári, Lajos; Hegyi, Zoltán; Csörgõ, Tibor; Hahn, István

    2000-07-01

    Tawny owls Strix aluco breeding in nest-boxes were studied in a mixed oak/hornbeam/beech forest located in the Duna-Ipoly National Park 30 km north-west of Budapest, Hungary, during the period 1992-1999. Diet composition, prey mass, breeding performance and body mass of the parents of known age were recorded. Older males had a greater ability to choose alternate prey, delivered a greater mass of prey with a higher feeding frequency and achieved higher productivity than younger males when the availability of the preferred prey declined. The reproductive cost was paid only by young parents. We suggest that the lowest breeding performance, which was observed with young parents in adverse weather conditions, may be due to both the lower ability of these younger birds to exploit alternative prey and to their poor body condition which resulted in them providing fewer resources to their offspring because of their need to provide for their own survival.

  1. Genetic diversity within lichen photobionts of the Lecanora varia group (Lichenes, Ascomycota)

    DEFF Research Database (Denmark)

    Pérez-Ortega, S.; Søchting, Ulrik; Printzen, C.

    partner of the symbiosis. Meanwhile, knowledge about photobiont diversity and the degree of photobiont selectivity of the fungus have been lacking behind. The Lecanora varia group is a set of species within the genus Lecanora defined by the presence of an amphitecial cortex along with the presence...... of usnic acid as secondary metabolite. We have focused on a small group of three species, namely L. varia, L. burgaziae, and L. densa which share very similar anatomical and morphological characters and an identical chemistry, with psoromic and 2-O-demethylpsoromic acids in addition to usnic acid. We have...... collected populations of these three species from various localities within their distributional range: L varia (Spain, Austria, Sweden, Czech Republic, western Siberia); L. burgaziae (Spain) and L. densa (North America and Spain). Subsequently, we sequenced the internal transcribed spacer (ITS) region...

  2. Clutch size variation in Tawny Owls (Strix aluco) from adjacent valley systems: can this be used as a surrogate to investigate temporal and spatial variations in vole density?

    Science.gov (United States)

    Steve J. Petty; Billy L. Fawkes

    1997-01-01

    Research on Tawny Owls (Strix aluco) in Kielder Forest, northern England, since 1981 demonstrated that field voles (Microtus agrestis) were their most important food. Here, field voles exhibited a 3-4 year cycle of abundance, and mean clutch size in Tawny Owls was significantly related to vole abundance in March. In this analysis...

  3. Interpolaci??n por recurrencia en varias variables

    OpenAIRE

    L??pez Carmona, Antonio

    1981-01-01

    Se hace un estudio a fondo de la interpolaci??n por recurrencia bajo una formulaci??n algebraica muy general que deja a las conocidas f??rmulas de interpolaci??n de Lagrange Newton Aitken y Neville como casos particulares de esta formulaci??n. Todos los resultados obtenidos los aplicamos a la interpolaci??n en varias variables de la que hacemos un importante estudio

  4. Modeling interactions betweenspotted owl and barred owl populations in fire-prone forests

    Science.gov (United States)

    Background / Question / Methods Efforts to conserve northern spotted owls (Strix occidentalis caurina) in the eastern Cascades of Washington must merge the challenges of providing sufficient structurally complex forest habitat in a fire-prone landscape with the limitations impos...

  5. Interpolación por recurrencia en varias variables

    OpenAIRE

    López Carmona, Antonio

    2013-01-01

    Se hace un estudio a fondo de la interpolación por recurrencia bajo una formulación algebraica muy general que deja a las conocidas fórmulas de interpolación de Lagrange Newton Aitken y Neville como casos particulares de esta formulación. Todos los resultados obtenidos los aplicamos a la interpolación en varias variables de la que hacemos un importante estudio

  6. Sound recordings of road maintenance equipment on the Lincoln National Forest, New Mexico

    Science.gov (United States)

    D. K. Delaney; T. G. Grubb

    2004-01-01

    The purpose of this pilot study was to record, characterize, and quantify road maintenance activity in Mexican spotted owl (Strix occidentalis lucida) habitat to gauge potential sound level exposure for owls during road maintenance activities. We measured sound levels from three different types of road maintenance equipment (rock crusherlloader,...

  7. [Effects of exogenous salicylic acid on seed germination and physiological characteristics of Coronilla varia under drought stress.

    Science.gov (United States)

    Ma, Le Yuan; Chen, Nian Lai; Han, Guo Jun; Li, Liang

    2017-10-01

    This research investigated the effects of different concentrations (0, 0.5, 1.0, 2.0 mmol·L -1 ) of salicylic acid on the seed germination and physiological characteristics of legume forage Coronilla varia (cultivar 'Lvbaoshi') under PEG-6000 (concentration 8% and 12%) simulated drought stress. The results showed that under drought stress, 0.5-1.0 mmol·L -1 salicylic acid significantly increased germination percentage, germination vigour, germination index, vitality index and bud length of C. varia. Under the stress of 12% PEG, the dry mass of C. varia seedlings processed by 1.0 mmol·L -1 salicylic acid was significantly higher than that under drought stress. 0.5-1.0 mmol·L -1 salicylic acid processing significantly increased proline, soluble protein content, the activities of catalase, peroxidase and superoxide dismutase of C. varia seedlings under drought stress, but cell electrolyte permeability, H2O2 content and O2 - · production rate of seedlings were significantly decreased. 1.0 mmol·L -1 salicylic acid produced the best results. When the concentration of salicylic acid was beyond 2.0 mmol·L -1 , no mitigation effect was observed on the seed germination and growth of seedlings under drought stress. It was concluded that salicylic acid at appropriate concentrations could effectively improve osmotic regulation, antioxidation and mitigate the damage of drought stress so as to promote the growth of C. varia seedlings.

  8. Variação morfológica e populacional de Trachemys dorbigni (Testudines, Emydidae) no extremo sul do Brasil

    OpenAIRE

    Silveira, Melise Lucas

    2014-01-01

    A presente dissertação, intitulada “Variação Morfológica e populacional de Trachemys dorbigni (Testudines, Emydidae) no extremo sul do Brasil”, encontra-se organizada em dois artigos. O primeiro artigo, intitulado “Variação geográfica na morfologia e estrutura populacional de Trachemys dorbigni (Testudines, Emydidae) no extremo sul do Brasil” e o segundo artigo, com o título: “Irregularidades no padrão de escudos de Trachemys dorbigni (Testudines, Emydidae): ontogenia e variação espacial”. Es...

  9. Accessible light detection and ranging: estimating large tree density for habitat identification

    Science.gov (United States)

    Heather A. Kramer; Brandon M. Collins; Claire V. Gallagher; John Keane; Scott L. Stephens; Maggi Kelly

    2016-01-01

    Large trees are important to a wide variety of wildlife, including many species of conservation concern, such as the California spotted owl (Strix occidentalis occidentalis). Light detection and ranging (LiDAR) has been successfully utilized to identify the density of large-diameter trees, either by segmenting the LiDAR point cloud into...

  10. Demographic response of northern spotted owls to barred owl removal

    Science.gov (United States)

    Diller, V. Lowell; Hamm, Keith A; Early, Desiree A; Lamphear, David W; Dugger, Katie M.; Yackulic, Charles B.; Schwarz, Carl J.; Carlson, Peter C.; McDonald, Trent L.

    2016-01-01

    Federally listed as threatened in 1990 primarily because of habitat loss, the northern spotted owl (Strix occidentalis caurina) has continued to decline despite conservation efforts resulting in forested habitat being reserved throughout its range. Recently, there is growing evidence the congeneric invasive barred owl (Strix varia) may be responsible for the continued decline primarily by excluding spotted owls from their preferred habitat. We used a long-term demographic study for spotted owls in coastal northern California as the basis for a pilot barred owl removal experiment. Our demography study used capture–recapture, reproductive output, and territory occupancy data collected from 1990 to 2013 to evaluate trends in vital rates and populations. We used a classic before-after-control-impact (BACI) experimental design to investigate the demographic response of northern spotted owls to the lethal removal of barred owls. According to the best 2-species dynamic occupancy model, there was no evidence of differences in barred or northern spotted owl occupancy prior to the initiation of the treatment (barred owl removal). After treatment, barred owl occupancy was lower in the treated relative to the untreated areas and spotted owl occupancy was higher relative to the untreated areas. Barred owl removal decreased spotted owl territory extinction rates but did not affect territory colonization rates. As a result, spotted owl occupancy increased in the treated area and continued to decline in the untreated areas. Prior to and after barred owl removal, there was no evidence that average fecundity differed on the 2 study areas. However, the greater number of occupied spotted owl sites on the treated areas resulted in greater productivity in the treated areas based on empirical counts of fledged young. Prior to removal, survival was declining at a rate of approximately 0.2% per year for treated and untreated areas. Following treatment, estimated survival was 0.859 for

  11. Managing emerging threats to spotted owls

    Science.gov (United States)

    Ho Yi Wan; Joseph L. Ganey; Christina D. Vojta; Samuel A. Cushman

    2018-01-01

    The 3 spotted owl (Strix occidentalis) subspecies in North America (i.e., northern spotted owl [S. o. caurina], California spotted owl [S. o. occidentalis], Mexican spotted owl [S. o. lucida]) have all experienced population declines over the past century due to habitat loss and fragmentation from logging. Now, the emerging influences of climate change, high-severity...

  12. Food habits of Mexican Spotted Owls in Arizona

    Science.gov (United States)

    Joseph L. Ganey

    1992-01-01

    The Spotted Owl (Strix occidentalis) is most common in mature and old-growth coniferous forests throughout much of its range (Forsman et al. 1984, Laymon 1988, Ganey and Balda 1989a, Thomas et al. 1990). Proximate factors underlying habitat selection in Spotted Owls are understood poorly. Abundance and availability of food, however, may be a key...

  13. Variações ecomorfológicas e de uso de habitat em Piabina argentea (Characiformes, Characidae da bacia do Rio das Velhas, Minas Gerais, Brasil

    Directory of Open Access Journals (Sweden)

    Cecília G. Leal

    2013-09-01

    Full Text Available O presente estudo teve como objetivo investigar os padrões local e regional de uso de habitat de Piabina argentea Reinhardt, 1867 em quatro diferentes rios da bacia do rio das Velhas. Os habitat amostrados foram caracterizados quanto à velocidade da água, profundidade e tipo de substrato. Para a análise ecomorfológica, foram calculados 17 atributos ecomorfológicos de 40 exemplares de cada rio. Embora estas populações tenham se sobreposto no espaço ecomorfológico, a Análise Discriminante Canônica mostrou haver diferença significativa entre elas, principalmente da população do rio das Velhas em relação às demais. A separação se deu em termos do índice de compressão, altura relativa do corpo e índice de achatamento ventral. Os padrões locais de seleção de habitat não foram congruentes em todos os rios, mas em geral, houve predomínio do padrão regional: habitat lênticos, profundidade entre 20 e 40 cm e 60 e 80 cm e substrato areia, silte+argila e banco de folhas. Considerando as características físicas de cada rio e o padrão regional da espécie, a maior parte dos seus requerimentos de habitat é contemplada nos quatro rios. Entretanto, um corpo d'água assoreado como o trecho do rio das Velhas, tende a ter maiores velocidades da água, menores profundidades e substrato finos, o que atende em parte à seleção de habitat da espécie estudada.

  14. Avian trichomonosis in spotted owls (Strix occidentalis: Indication of opportunistic spillover from prey

    Directory of Open Access Journals (Sweden)

    Krysta H. Rogers

    2016-12-01

    Full Text Available Avian trichomonosis, caused by the flagellated protozoan parasite Trichomonas gallinae, has variable pathogenicity among bird species ranging from asymptomatic infections to severe disease periodically manifesting in epidemic mortality. Traditionally, columbids are identified as highly susceptible to infection with occasional spillover into raptors that prey on infected birds. We identified avian trichomonosis in two dead California spotted owls (Strix occidentalis occidentalis and three dead northern spotted owls (S. o. caurina in California during 2011–2015; infection was confirmed in four owls by PCR. Pathologic lesions associated with trichomonosis in the owls included caseonecrotic lesions of the upper palate accompanied by oropharyngitis, cellulitis, myositis, and/or sinusitis. Spotted owls are known to mainly feed on small mammals; therefore, the source of infection as well as the significance of the disease in spotted owls is unclear. These owl trichomonosis cases coincided temporally and spatially with three trichomonosis epidemics in band-tailed pigeons (Patagioenas fasciata monilis. The same parasite, T. gallinae subtype A2, was isolated from the spotted owls and band-tailed pigeons, suggesting the owls became infected when opportunistically feeding on pigeons during mortality events. Avian trichomonosis is an important factor in the decline of the Pacific Coast band-tailed pigeon population with near-annual mortality events during the last 10 years and could have conservation implications for raptor species at risk, particularly those that are facing multiple threats.

  15. The effects of habitat, climate, and Barred Owls on long-term demography of Northern Spotted Owls

    Science.gov (United States)

    Katie M. Dugger; Eric D. Forsman; Alan B. Franklin; Raymond J. Davis; Gary C. White; Carl J. Schwarz; Kenneth P. Burnham; James D. Nichols; James E. Hines; Charles B. Yackulic; Paul F. Doherty; Larissa Bailey; Darren A. Clark; Steven H. Ackers; Lawrence S. Andrews; Benjamin Augustine; Brian L. Biswell; Jennifer Blakesley; Peter C. Carlson; Matthew J. Clement; Lowell V. Diller; Elizabeth M. Glenn; Adam Green; Scott A. Gremel; Dale R. Herter; J. Mark Higley; Jeremy Hobson; Rob B. Horn; Kathryn P. Huyvaert; Christopher McCafferty; Trent McDonald; Kevin McDonnell; Gail S. Olson; Janice A. Reid; Jeremy Rockweit; Viviana Ruiz; Jessica Saenz; Stan G. Sovern

    2016-01-01

    Estimates of species’ vital rates and an understanding of the factors affecting those parameters over time and space can provide crucial information for management and conservation. We used mark–recapture, reproductive output, and territory occupancy data collected during 1985–2013 to evaluate population processes of Northern Spotted Owls (Strix occidentalis...

  16. Diet of the Tawny Owl Strix aluco in the area of Slovenske gorice (NE Slovenia

    Directory of Open Access Journals (Sweden)

    Janžekovič Franc

    2017-11-01

    Full Text Available The diet of Tawny Owl Strix aluco was studied in the area of Slovenske gorice - NE Slovenia. The analysis was carried out by examining pellets collected at ten locations in the period from 1984 to 2015. From the pellets, 2,121 prey units were isolated. The predominant prey were mammals (Mammalia, 84.8%, followed by birds (Aves, 8.3%, insects (Insecta, 4.7%, frogs (Anura, 1.6% and earthworms (Oligochaeta, 0.5%. Four orders of mammals were found: rodents (Rodentia, insectivores (Insectivora, bats (Chiroptera and carnivores (Carnivora. The most frequent prey in the owls’ diet were voles (Arvicolinae, 46.6% and mice (Murinae, 28.8%, while the number of shrews (Soricidae was low (4.5%. The obtained results are in concordance with the conclusions of other studies. In the area of Slovenske gorice, the Tawny Owl is an opportunistic predator of small mammals with an emphasis on voles and mice. Prey frequencies differ significantly among some localities. Variability in proportions of prey species among localities can also be the result of sampling carried out in different seasons and variability in the population dynamics of small mammals among years. Challenges for future research are to describe seasonal variability of the diet and to evaluate interspecific competition within the guild of night predators of small mammals: Tawny Owl, Long-eared Owl Asio otus, and Barn Owl Tyto alba, which are sympatric in this area.

  17. J.S.Bach variações "Goldberg" : um guia para a formação do homem completo

    OpenAIRE

    Helena Jank

    1988-01-01

    Resumo: Dentre muitas formas possíveis de abordagem para esta obra monumental de J. S. Bach, o presente trabalho traz um enfoque eminentemente humanístico, através do qual transparece a intenção do compositor de estruturar, na forma de tema e variações um ?guia para a formação do homem completo? Esta intenção se manifesta na organização geral da obra, com uma clara divisão em três grupos de variações, nos quais são explorados aspectos técnicos, composicionais e de interpretação. Com base na ...

  18. Variações no posicionamento dos eixos visuais em pacientes submetidos a cirurgias de estrabismo

    Directory of Open Access Journals (Sweden)

    Graciela Scalco Brum

    2011-02-01

    Full Text Available OBJETIVOS: Determinar as variações no ângulo de posicionamento ocular pós-operatório em pacientes submetidos a cirurgias para correção de estrabismo e identificar possíveis fatores de risco associados a tal ocorrência. MÉTODOS: Foi realizado estudo retrospectivo de 819 pacientes portadores de estrabismo submetidos à cirurgia para correção do desvio ocular entre janeiro de 1995 e dezembro de 2005 no Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo. Os pacientes foram divididos em quatro grupos quanto ao tipo de desvio pré-operatório (esotropia alternante, esotropia monocular, exotropia alternante e exotropia monocular e as variações no posicionamento ocular foram quantificadas em cada grupo. RESULTADOS: A prevalência de variações no posicionamento ocular (pós-operatório maiores que 10∆ entre o total de pacientes estudado foi de 33,5% (274 pacientes. Entre estes, foi verificada maior frequência de desvios no sentido exotrópico (178 pacientes ou 65,0% do que no sentido esotrópico (96 pacientes ou 35,0%, diferença esta que foi estatisticamente significativa (teste do qui-quadrado; p<0,001. CONCLUSÕES: Instabilidade no posicionamento ocular pode ocorrer ao longo do tempo em pacientes submetidos a cirurgias de estrabismo. Tal ocorrência reforça a necessidade do desenvolvimento de alternativas terapêuticas a fim de proporcionar maior estabilidade ao sistema oculomotor no pós-operatório de cirurgias de estrabismo.

  19. Variação anatômica no lenho de Astronium lecointei Ducke

    Directory of Open Access Journals (Sweden)

    Luiz Eduardo de Lima Melo

    Full Text Available Com o objetivo de avaliar a variação dos elementos celulares de Astronium lecointei Ducke no sentido medula-câmbio, analisaram-se amostras de madeira de três regiões radiais da árvore, a 1,30 m do solo: 0% (próximo à medula, 50% (região intermediária e 100% (próximo ao câmbio vascular. A metodologia aplicada no trabalho foi aquela tradicionalmente recomendada para estudos em anatomia de madeira, seguindo orientação do IAWA Committee. Observou-se que alguns elementos anatômicos apresentaram tendências de variação definidas e estatisticamente significativas: frequência, diâmetro e comprimento dos elementos de vaso, altura dos raios em micrômetros e comprimento das fibras. Observou-se também maior obstrução dos poros por tilas próximo à medula e na região intermediária. A tendência de estabilização das dimensões dessas estruturas pode estar indicando a formação de madeira adulta a partir da região intermediária analisada no lenho da espécie.

  20. O tratamento da diversidade e variação linguísticas em livros didáticos de Português

    Directory of Open Access Journals (Sweden)

    Cláudia Goulart Morais

    2015-12-01

    Full Text Available Neste trabalho, analiso como a diversidade e a variação linguísticas são tratadas nos Livros Didáticos de Português (LDP nos anos finais do ensino fundamental, na tentativa de problematizar como as atividades propostas nesses materiais didáticos tematizam conceitos sociolinguísticos importantes, tais como o conceito de norma e as relações entre fala e escrita e oralidade e letramento. As análises dos dados validaram a nossa hipótese de que nos LDP, que circulam atualmente nas escolas brasileiras, ainda predomina a submissão das marcas da diversidade e da variação linguísticas aos processos de normatização da língua, mesmo onde se propõe apresentar e discutir a variação linguística. As análises validaram, também, o nosso entendimento de que tais atividades dos LDP fazem parte do processo de valorização da norma padrão como a única variedade legítima e a modalidade escrita formal como aquela gramaticalmente organizada.

  1. Two common and problematic leucochrysine species – Leucochrysa (Leucochrysa varia (Schneider and L. (L. pretiosa (Banks (Neuroptera, Chrysopidae: redescriptions and synonymies

    Directory of Open Access Journals (Sweden)

    Catherine Tauber

    2013-06-01

    Full Text Available Leucochrysa McLachlan is the largest genus in the Chrysopidae, yet it has received relatively little taxonomic attention. We treat two problematic and common Leucochrysa species – Leucochrysa (Leucochrysa varia (Schneider, 1851 and Leucochrysa (Leucochrysa pretiosa (Banks, 1910. Both are highly variable in coloration and were described before the systematic importance of chrysopid genitalia was recognized. Recent studies show that these species occur within a large complex of cryptic species and that they have accumulated a number of taxonomic problems. We identify new synonymies for each of the species – for L. (L. varia: Leucochrysa (Leucochrysa ampla (Walker, 1853, Leucochrysa internata (Walker, 1853, and Leucochrysa (Leucochrysa walkerina Navás, 1913; for L. (L. pretiosa: Leucochrysa erminea Banks 1946. The synonymy of Leucochrysa delicata Navás 1925 with L. (L. pretiosa is stabilized by the designation of a neotype. The following species, which were previously synonymized with L. (L. varia or L. (L. pretiosa, are reinstated as valid: Leucochrysa phaeocephala Navás 1929, Leucochrysa (Leucochrysa angrandi (Navás, 1911, and Leucochrysa (Leucochrysa variata (Navás, 1913. Finally, Leucochrysa vegana Navás 1917 is considered a nomen dubium.

  2. ECOLOGICAL RISK ASSESSMENT OF ALFALFA (MEDICAGO VARIA L.) GENETICLALY ENGINEERED TO EXPRESS A HUMAN METALLOTHIONEIN (HMT) GENE

    Science.gov (United States)

    The objectives of these studies were two-fold: (1) to determine efficacy of low and high expression hMT gene constructs by assessing accumulation of Cu in shoots of parental and transgenic plants of alfalfa (Medicago varia L.) exposed to different concentrations of CuSO4 by addit...

  3. Stratification of habitats for identifying habitat selection by Merriam's turkeys

    Science.gov (United States)

    Mark A. Rumble; Stanley H. Anderson

    1992-01-01

    Habitat selection patterns of Merriam’s Turkeys were compared in hierarchical analyses of three levels of habitat stratification. Habitat descriptions in first-level analyses were based on dominant species of vegetation. Habitat descriptions in second-level analyses were based on dominant species of vegetation and overstory canopy cover. Habitat descriptions in third-...

  4. Variação temporal do gradiente radial de o/h a partir de uma amostra de nebulosas planetárias

    Science.gov (United States)

    Maciel, W. J.; Costa, R. D. D.; Uchida, M. M. M.

    2003-08-01

    Gradientes radiais de abundância são observados no disco de nossa Galáxia e também em outras galáxias espirais. No caso da Galáxia, o principal problema relativo aos gradientes é sua variação temporal, que constitui um dos principais vínculos aos modelos de evolução química da Galáxia. As nebulosas planetárias são particularmente interessantes no estudo dos gradientes e suas variações, tanto espaciais como temporais. São objetos brilhantes, podendo ser observadas a grandes distâncias, e têm abundâncias relativamente precisas de diversos elementos químicos. Além disso, sendo originadas de estrelas com massas entre 0.8 e 8 massas solares na sequência principal, incluem objetos com idades e populações diferentes, o que as torna especialmente interessantes ao estudo da variação temporal dos gradientes. Neste trabalho, apresentamos resultados recentes sobre a variação temporal do gradiente de O/H a partir de uma amostra contendo cerca de 200 nebulosas, para as quais obtivemos distâncias por métodos estatísticos. As abundâncias foram parcialmente obtidas a partir de observações em Itajubá e La Silla, sendo as restantes obtidas da literatura. Os resultados mostram, pela primeira vez, evidências de um achatamento do gradiente de O/H, de -0.11 dex/kpc para -0.06 dex/kpc nos últimos 9 giga-anos ou de -0.08 dex/kpc para -0.06 dex/kpc nos últimos 5 giga-anos. Esses valores apresentam um bom acordo com alguns modelos recentes para a evolução química da Galáxia. (FAPESP/CNPq)

  5. ANALISIS PENETAPAN HARGA JUAL BERDASARKAN TARGET COSTING PADA PT VARIA USAHA BETON PLANT BM MAKASSAR

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    ASHAR MUNTA

    2017-05-01

    The Results showed there are differences in the price of Paving Blocks namely (1 in 2012 the difference between the price of Rp 25.70. (2 In 2013 the price difference Rp 3,31. And (3 In 2014 the difference between the price of Rp 1,37. Which means that the Target Costing Method is better than the Conventional Method in PT Varia Usaha Beton Plant BM Makassar.

  6. Importância clínica do músculo esternal e suas variações anatômicas: uma revisão sistemática da literatura

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    Luana Agapito de Oliveira

    2017-08-01

    Full Text Available A presença do músculo esternal é uma variação anatômica que está situada anteriormente ao osso esterno e suas estruturas adjacentes e não tem função totalmente definida. Há na literatura mais relatos de estudos anatômicos sobre o músculo esternal do que sobre as implicações clínicas da sua presença. O objetivo deste estudo foi analisar as descrições existentes das variações anatômicas do músculo esternal, compreendendo, assim, a importância clínica desse conhecimento. Foram avaliados artigos nas línguas portuguesa e inglesa, indexados nas bases de dados PubMed e SciELO, publicados entre 1867 e 2016. Buscou-se verificar os tipos de variações anatômicas do músculo esternal descritas, suas origens e inserções, inervação e irrigação sanguínea. Em seguida, foi relatada a importância clínica do conhecimento dessa variação. O músculo esternal apresenta diversas dimensões e inserções, o que dificulta a determinação de sua função. Devido à localização paraesternal, em exames de imagem o referido músculo pode ser visto como uma nodulação anormal na região da mama e ser confundido com um tumor. O reconhecimento dessa variação antes de procedimentos cirúrgicos na parede torácica evita possíveis complicações e possibilita o uso do tecido como retalho muscular em cirurgias reconstrutivas da mama; também pode ser usado na melhora de resultados estéticos em mamoplastia de aumento ou fornecer cobertura extra para próteses. O conhecimento sobre essa variação anatômica é bastante relevante, pois a percepção da existência do músculo esternal e de suas variações relaciona-se a importantes implicações clínicas em cirurgias de mama e tórax.

  7. Habitat Use Database - Groundfish Essential Fish Habitat (EFH) Habitat Use Database (HUD)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Habitat Use Database (HUD) was specifically designed to address the need for habitat-use analyses in support of groundfish EFH, HAPCs, and fishing and nonfishing...

  8. Modeling co-occurrence of northern spotted and barred owls: accounting for detection probability differences

    Science.gov (United States)

    Bailey, Larissa L.; Reid, Janice A.; Forsman, Eric D.; Nichols, James D.

    2009-01-01

    Barred owls (Strix varia) have recently expanded their range and now encompass the entire range of the northern spotted owl (Strix occidentalis caurina). This expansion has led to two important issues of concern for management of northern spotted owls: (1) possible competitive interactions between the two species that could contribute to population declines of northern spotted owls, and (2) possible changes in vocalization behavior and detection probabilities of northern spotted owls induced by presence of barred owls. We used a two-species occupancy model to investigate whether there was evidence of competitive exclusion between the two species at study locations in Oregon, USA. We simultaneously estimated detection probabilities for both species and determined if the presence of one species influenced the detection of the other species. Model selection results and associated parameter estimates provided no evidence that barred owls excluded spotted owls from territories. We found strong evidence that detection probabilities differed for the two species, with higher probabilities for northern spotted owls that are the object of current surveys. Non-detection of barred owls is very common in surveys for northern spotted owls, and detection of both owl species was negatively influenced by the presence of the congeneric species. Our results suggest that analyses directed at hypotheses of barred owl effects on demographic or occupancy vital rates of northern spotted owls need to deal adequately with imperfect and variable detection probabilities for both species.

  9. Variação estacional da oferta e preços de couve-flor em Minas Gerais

    Directory of Open Access Journals (Sweden)

    Luis Felipe Lima e Silva

    2014-06-01

    Full Text Available Em virtude da variedade de cultivares atualmente disponíveis, de suas diferentes exigências climáticas e das diferenças climáticas entre as várias regiões produtoras, a couve-flor pode apresentar variações estacionais de oferta e de preços ao longo do ano. O objetivo do presente trabalho foi estudar a variação estacional da oferta e dos preços da couve-flor praticados no Estado de Minas Gerais, representados pelas unidades da CEASAMINAS, bem como as componentes dessa oferta para cada principal região abastecedora do Estado, no período de 2005 a 2009. A unidade CEASAMINAS (Grande BH foi responsável por 68% da comercialização anual de couve-flor em Minas Gerais por meio das unidades da CEASAMINAS, que oscilou entre 9.420 e 10.937 toneladas anuais. A quase totalidade de produção proveio de municípios mineiros, localizados em quatro grandes mesorregiões: Região Metropolitana de Belo Horizonte, Campo das Vertentes, Triângulo Mineiro e Vale do Rio Doce, que representaram, respectivamente, 49%, 28%, 9% e 6% da oferta anual. As variações estacionais de oferta refletiram claramente as limitações dos cultivares atualmente disponíveis e a necessidade de novos cultivares que possam tolerar as grandes oscilações de temperatura nos meses de meia estação. Também ficou evidente que, a despeito da disponibilidade de cultivares de verão, a produção de couve-flor ainda é mais baixa nessa época do ano, um reflexo provável da alta precipitação que ocasiona maiores perdas por doenças na lavoura e em pós-colheita.

  10. Surface Habitat Systems

    Science.gov (United States)

    Kennedy, Kriss J.

    2009-01-01

    The Surface Habitat Systems (SHS) Focused Investment Group (FIG) is part of the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) effort to provide a focused direction and funding to the various projects that are working on human surface habitat designs and technologies for the planetary exploration missions. The overall SHS-FIG effort focuses on directing and guiding those projects that: 1) develop and demonstrate new surface habitat system concepts, innovations, and technologies to support human exploration missions, 2) improve environmental systems that interact with human habitats, 3) handle and emplace human surface habitats, and 4) focus on supporting humans living and working in habitats on planetary surfaces. The activity areas of the SHS FIG described herein are focused on the surface habitat project near-term objectives as described in this document. The SHS-FIG effort focuses on mitigating surface habitat risks (as identified by the Lunar Surface Systems Project Office (LSSPO) Surface Habitat Element Team; and concentrates on developing surface habitat technologies as identified in the FY08 gap analysis. The surface habitat gap assessment will be updated annually as the surface architecture and surface habitat definition continues to mature. These technologies are mapped to the SHS-FIG Strategic Development Roadmap. The Roadmap will bring to light the areas where additional innovative efforts are needed to support the development of habitat concepts and designs and the development of new technologies to support of the LSSPO Habitation Element development plan. Three specific areas of development that address Lunar Architecture Team (LAT)-2 and Constellation Architecture Team (CxAT) Lunar habitat design issues or risks will be focused on by the SHS-FIG. The SHS-FIG will establish four areas of development that will help the projects prepare in their planning for surface habitat systems development. Those development areas are

  11. Riverine habitat dynamics

    Science.gov (United States)

    Jacobson, R.B.

    2013-01-01

    The physical habitat template is a fundamental influence on riverine ecosystem structure and function. Habitat dynamics refers to the variation in habitat through space and time as the result of varying discharge and varying geomorphology. Habitat dynamics can be assessed at spatial scales ranging from the grain (the smallest resolution at which an organism relates to its environment) to the extent (the broadest resolution inclusive of all space occupied during its life cycle). In addition to a potentially broad range of spatial scales, assessments of habitat dynamics may include dynamics of both occupied and nonoccupied habitat patches because of process interactions among patches. Temporal aspects of riverine habitat dynamics can be categorized into hydrodynamics and morphodynamics. Hydrodynamics refers to habitat variation that results from changes in discharge in the absence of significant change of channel morphology and at generally low sediment-transport rates. Hydrodynamic assessments are useful in cases of relatively high flow exceedance (percent of time a flow is equaled or exceeded) or high critical shear stress, conditions that are applicable in many studies of instream flows. Morphodynamics refers to habitat variation resulting from changes to substrate conditions or channel/floodplain morphology. Morphodynamic assessments are necessary when channel and floodplain boundary conditions have been significantly changed, generally by relatively rare flood events or in rivers with low critical shear stress. Morphodynamic habitat variation can be particularly important as disturbance mechanisms that mediate population growth or for providing conditions needed for reproduction, such as channel-migration events that erode cutbanks and provide new pointbar surfaces for germination of riparian trees. Understanding of habitat dynamics is increasing in importance as societal goals shift toward restoration of riverine ecosystems. Effective investment in restoration

  12. Two common and problematic leucochrysine species - Leucochrysa (Leucochrysa) varia (Schneider) and L. (L.) pretiosa (Banks) (Neuroptera, Chrysopidae): redescriptions and synonymies.

    Science.gov (United States)

    Tauber, Catherine A; Sosa, Francisco; Albuquerque, Gilberto S

    2013-01-01

    We dedicate this article to the memory of Sergio de Freitas, FCAV-UNESP, Jaboticabal, São Paulo, Brazil (deceased, 2012). He was an active and enthusiastic Neuropterist and the cherished mentor and friend of Francisco Sosa. Leucochrysa McLachlan is the largest genus in the Chrysopidae, yet it has received relatively little taxonomic attention. We treat two problematic and common Leucochrysa species - Leucochrysa (Leucochrysa) varia (Schneider, 1851) and Leucochrysa (Leucochrysa) pretiosa (Banks, 1910). Both are highly variable in coloration and were described before the systematic importance of chrysopid genitalia was recognized. Recent studies show that these species occur within a large complex of cryptic species and that they have accumulated a number of taxonomic problems. We identify new synonymies for each of the species-for Leucochrysa (Leucochrysa) varia: Leucochrysa (Leucochrysa) ampla (Walker, 1853), Leucochrysa internata (Walker, 1853), and Leucochrysa (Leucochrysa) walkerina Navás, 1913; for Leucochrysa (Leucochrysa) pretiosa: Leucochrysa (Leucochrysa) erminea Banks, 1946. The synonymy of Leucochrysa delicata Navás, 1925 with Leucochrysa (Leucochrysa) pretiosa is stabilized by the designation of a neotype. The following species, which were previously synonymized with Leucochrysa (Leucochrysa) varia or Leucochrysa (Leucochrysa) pretiosa, are reinstated as valid: Leucochrysa (Leucochrysa) phaeocephala Navás, 1929, Leucochrysa (Leucochrysa) angrandi (Navás, 1911), and Leucochrysa (Leucochrysa) variata (Navás, 1913). To help stabilize Leucochrysa taxonomy, lectotypes are designated for Allochrysa pretiosa and Allochrysa variata. Finally, Leucochrysa vegana Navás, 1917 is considered a nomen dubium.

  13. Habitat-related specialization of lateral-line system morphology in a habitat-generalist and a habitat-specialist New Zealand eleotrid.

    Science.gov (United States)

    Vanderpham, J P; Nakagawa, S; Senior, A M; Closs, G P

    2016-04-01

    An investigation of intraspecific habitat-related patterns of variation in oculoscapular lateral-line superficial neuromasts (SN) identified a decrease in the ratio of total SNs to pores, and a trend towards decreased asymmetry in SNs in the habitat-generalist common bully Gobiomorphus cotidianus from fluvial habitats compared to lacustrine habitats, suggesting habitat-related phenotypic variability. A greater ratio of pores to SNs, as well as less variation in the total number and asymmetry of SNs observed in the fluvial habitat-specialist redfin bully Gobiomorphus huttoni may provide further evidence of variations in the oculoscapular lateral-line morphology of fluvial habitat G. cotidianus individuals serving as adaptations to more turbulent environments. © 2016 The Fisheries Society of the British Isles.

  14. An approach of habitat degradation assessment for characterization on coastal habitat conservation tendency.

    Science.gov (United States)

    Zhou, Xi-Yin; Lei, Kun; Meng, Wei

    2017-09-01

    Coastal zones are population and economy highly intensity regions all over the world, and coastal habitat supports the sustainable development of human society. The accurate assessment of coastal habitat degradation is the essential prerequisite for coastal zone protection. In this study, an integrated framework of coastal habitat degradation assessment including landuse classification, habitat classifying and zoning, evaluation criterion of coastal habitat degradation and coastal habitat degradation index has been established for better regional coastal habitat assessment. Through establishment of detailed three-class landuse classification, the fine landscape change is revealed, the evaluation criterion of coastal habitat degradation through internal comparison based on the results of habitat classifying and zoning could indicate the levels of habitat degradation and distinguish the intensity of human disturbances in different habitat subareas under the same habitat classification. Finally, the results of coastal habitat degradation assessment could be achieved through coastal habitat degradation index (CHI). A case study of the framework is carried out in the Circum-Bohai-Sea-Coast, China, and the main results show the following: (1) The accuracy of all land use classes are above 90%, which indicates a satisfactory accuracy for the classification map. (2) The Circum-Bohai-Sea-Coast is divided into 3 kinds of habitats and 5 subareas. (3) In the five subareas of the Circum-Bohai-Sea-Coast, the levels of coastal habitat degradation own significant difference. The whole Circum-Bohai-Sea-Coast generally is in a worse state according to area weighting of each habitat subarea. This assessment framework of coastal habitat degradation would characterize the landuse change trend, realize better coastal habitat degradation assessment, reveal the habitat conservation tendency and distinguish intensity of human disturbances. Furthermore, it would support for accurate coastal

  15. Variações nos períodos de pulsação das estrelas PG 1159-035 e G117-B15-A

    Science.gov (United States)

    Costa, J. E. S.; Kepler, S. O.

    2003-08-01

    A medida que uma estrela evolui, sua trajetória no diagrama-HR passa pelas chamadas "faixas de instabilidade" podendo tornar-se uma variável. Ao longo da seqüência das anãs brancas existem três faixas de instabilidade, contando com a faixa das pré-anãs brancas (DOs). Estrelas nestas faixas podem apresentar pulsações não-radiais com períodos bastante estáveis, ente 100 e 1000 segundos. Os períodos de pulsação sofrem variações com a evolução da estrela, podendo aumentar ou diminuir. As DOs, por serem mais quentes evoluem mais rapidamente e isto faz com que as variações em seus períodos de pulsação sejam maiores (em magnitude) do que as variações que ocorrem nos períodos de pulsação de anãs brancas pulsantes mais frias como as DBs e as DAs. Neste trabalho apresentamos os resultados das medidas das variações de períodos de pulsação de duas estrelas: a PG 1159-035 e a G117-B15-A. Essas duas estrelas estão nos extremos da seqüência das anãs brancas: a PG 1159-035 é uma pré-anã branca (DO) e seus períodos de pulsação variam na ordem de 1 segundo a cada 3000 anos. Já a G117-B15-A é uma DA e seus períodos de pulsação variam cerca de 1 segundo a cada 30 milhões de anos.

  16. A variação denominativa nos textos especializados da aromaterapia: o caso da unidade terminológica Alecrim = Rosemary variation within Aromatherapy texts

    Directory of Open Access Journals (Sweden)

    Neide Munhoz Albano

    2010-07-01

    Full Text Available Este artigo objetiva discutir a variação da planta Alecrim, no âmbito da denominação científica e popular, na ótica do prescritivismo das teorias da variação linguística. A análise concentra-se nas variantes terminológicas em consonância com seu uso.This article aims to discuss variation with respect to the scientific and common denominations of the Rosemary plant, based on the approach of prescription of the theories of linguistic variation. The analysis focuses on the terminological variants in consonance with their use by experts in the field.

  17. Dupla variação anatômica vascular em um único indivíduo: estudo morfométrico

    Directory of Open Access Journals (Sweden)

    Cristiane Regina Ruiz

    2017-12-01

    Full Text Available Introdução: Variações anatômicas são pequenas diferenças morfológicas congênitas que aparecem nos diferentes sistemas orgânicos, as quais não acarretam prejuízo ou distúrbio funcional para o indivíduo. No que diz respeito aos vasos sanguíneos, alterações no desenvolvimento embriológico podem gerar duplicidade de vasos, agenesia ou ocasionar o surgimento de artérias e o desembocar de veias fora da descrição anatômica padrão. Relato de caso: Foi observada dupla variação anatômica vascular em um indivíduo durante uma dissecação de rotina no Laboratório de Anatomia do Centro Universitário São Camilo. A artéria renal principal tinha origem na parte abdominal da artéria aorta seguindo até sua entrada no hilo renal, porém, em vez de um trajeto retilíneo a partir da aorta, a mesma possuía um trajeto descendente e bem angulado. A partir da artéria renal principal surgia uma artéria polar aberrante que entrava no polo inferior do rim direito. Em um nível mais inferior, na altura da bifurcação da aorta, originava-se outra artéria polar aberrante que entrava no hilo renal, seguindo um trajeto retilíneo até o polo inferior do rim direito. A artéria hepática comum originava-se no tronco celíaco seguindo até sua entrada na porta do fígado. A artéria mesentérica superior possuía origem no tronco celíaco. A artéria hepática direita originava-se na artéria mesentérica superior. Conclusão: O estudo das variações anatômicas constitui-se tarefa árdua em virtude das inúmeras expressões diferentes que ocorrem no corpo humano, porém, o conhecimento dessas variações é de extrema valia para a clínica e o planejamento cirúrgico, garantindo a precisão e evitando complicações pós-cirúrgicas ou diagnósticos errôneos.

  18. The Habitat Connection.

    Science.gov (United States)

    Naturescope, 1987

    1987-01-01

    Consists of activities which address the causes of habitat destruction and the effects of habitat loss on animals and plants. Identifies habitat loss as the major reason for the endangerment and extinction of plant and animal species. (ML)

  19. Dynamics of fish assemblages on a continuous rocky reef and adjacent unconsolidated habitats at Fernando de Noronha Archipelago, tropical western Atlantic

    Directory of Open Access Journals (Sweden)

    Paulo R. Medeiros

    2011-01-01

    que é atualmente conhecida, no entanto, é oriunda de comparações de recifes isolados e de correlações entre abundância de peixes e uma ou poucas variáveis relacionadas ao microhabitat. Ainda, a maior parte dos estudos foi realizada nas regiões do Caribe e do Indo-Pacífico, enquanto a região do Atlântico Sul tem sido, até o momento, subestimada. O presente estudo avaliou as variações espaciais e temporais da abundância de peixes recifais e da riqueza de espécies em um recife rochoso contínuo e em habitats não-consolidados adjacentes em um recife do Atlântico Sudoeste, utilizando técnicas subaquáticas para avaliar tanto os valores dos peixes como as variáveis do microhabitat (profundidade, rugosidade, número de fendas e porcentagem de cobertura de organismos bênticos vivos, rocha nua, areia e cascalho. Uma maior riqueza de espécies foi observada nos pontos de substrato consolidado em ambos os períodos de amostragem (maio e outubro, mas a abundância de peixes não mostrou uma variação espacial significativa. A complexidade topográfica e a porcentagem de cobertura de alga (exceto alga coralinácea foram as determinantes da riqueza de espécies e correlações entre tamanho dos peixes e tamanho das fendas de refúgio mais importantes observadas. Os padrões não-randômicos de variação espacial na riqueza de espécies e, em menor grau, abundância de peixes, relacionaram-se com diferenças nas características do substrato e as características inerentes dos peixes (i.e. preferências de habitat e não a barreiras geográficas restringindo o movimento dos peixes. Este estudo destaca a importância de avaliar concomitantemente diversas variáveis de microhabitat para determinar suas influências relativas sobre as assembleias de peixes.

  20. Estudo da massa específica básica e da variação dimensional da madeira de três espécies de eucalipto para a indústria moveleira

    Directory of Open Access Journals (Sweden)

    Camila Santos Doubek Lopes

    2011-06-01

    Full Text Available A utilização da madeira de árvores de espécies de reflorestamento pela indústria moveleira tem apresentado tendência de crescimento nos últimos anos. Nesse sentido, no presente trabalho foram determinadas a massa específica básica e variação dimensional da madeira de árvores de Eucalyptus grandis, Eucalyptus dunnii e Eucalyptus urophylla, de 18 anos, para a aplicação como componentes de madeira maciça em movelaria. Os ensaios laboratoriais para a avaliação da massa específica básica e da variação dimensional da madeira nos sentidos radial e longitudinal do tronco das árvores de eucaliptos foram realizados de acordo com a NBR 7190/96. Os resultados da análise da madeira das espécies de eucalipto foram submetidos ao Teste de Homogeneidade, Análise de Variância, Teste de Tukey e Correlação de Pearson e comparados com o desempenho da madeira de sucupira (Bowdichia nitida e de cumaru (Dipteryx odorata utilizadas na indústria moveleira. Verificou-se para a madeira de Eucalyptus grandis menor valor de variação dimensional, sendo a mais indicada para componentes de móveis que exigem elevada estabilidade dimensional, além de peças de maior superfície. A madeira dessa espécie apresentou índice de variação dimensional compatível com o de espécies nativas utilizadas na indústria moveleira. Verificou-se, ainda, variação radial das propriedades da madeira, com alta correlação entre a massa específica básica e a variação dimensional. No sentido longitudinal, a base do tronco das árvores de eucalipto mostrou-se com a região de madeira de maior estabilidade dimensional.

  1. Diversity and associations between coastal habitats and anurans in southernmost Brazil

    Directory of Open Access Journals (Sweden)

    MAURO C.L.M. OLIVEIRA

    Full Text Available This study aimed to verify the relationship between habitat and the composition of anuran species in dune and restinga habitats in southernmost Brazil. The habitats were sampled between April 2009 and March 2010 using pitfalls with drift fence. We have captured 13,508 individuals of 12 anuran species. Species richness was lower in the dunes and dominance was higher in the resting. Apparently the less complex plant cover, water availability, and wide daily thermal variation in dunes act as an environmental filter for frogs. This hypothesis is reinforced by the fact that the most abundant species (Physalaemus biligonigerus and Odonthoprynus maisuma bury themselves in the sand, minimizing these environmental stresses. Despite being in the Pampa biome, the studied community was more similar to those of coastal restinga environment of southeast Brazil than with other of the Pampa biome. The number of recorded species is similar to those observed in other open habitats in Brazil, showing the importance of adjacent ones to the shoreline for the maintenance of the diversity of anurans in southernmost Brazil.Este estudo teve como objetivo verificar a relação entre o hábitat e a composição de espécies de anuros em ambientes de duna e restinga no extremo sul do Brasil. Estes ambientes foram amostrados entre abril de 2009 e março de 2010 utilizando armadilhas de interceptação e queda, com barreira de contenção. Foram capturados 13.508 indivíduos de 12 espécies de anuros. A riqueza de espécies foi menor nas dunas e dominância foi maior na restinga. Aparentemente, a cobertura vegetal, com menor complexidade, a disponibilidade de água e a maior variação térmica diária nas dunas, atuam como um filtro ambiental para os anuros. Esta hipótese é reforçada pelo fato de que as espécies mais abundantes (Physalaemus biligonigerus e Odonthoprynus maisuma se enterram na areia, minimizando esses estresses ambientais. Apesar de estar no bioma Pampa

  2. Contabilização das variações da necessidade de capital de giro

    Directory of Open Access Journals (Sweden)

    André Seidel

    2003-04-01

    Full Text Available Quando se deseja iniciar uma atividade ou mesmo expandi-la, muito se analisa a necessidade de aplicações em ativos permanentes, mas pouca atenção é dedicada ao "investimento em clientes e estoques". Dessa forma a concessão de prazo para clientes ou a opção por um aumento nos níveis dos estoques, ambos valores contabilizados no ativo circulante, pode significar uma decisão de investimento tão ou mais duradoura do que aquela efetuada em ativos permanentes. A Necessidade de Capital de Giro (NCG, e suas variações, podem levar à falência muitas empresas, principalmente pequenas e médias. Além da preocupação monetária, uma empresa necessita garantir a manutenção de sua estrutura física, permanente e operacional, necessária para suas atividades. O lucro contabilizado através do Custo Corrente Corrigido (CCC, precisa de ajustes para ser considerado totalmente distribuível; sob nosso ponto de vista, as variações da NCG fazem parte desses ajustes. A idéia central deste artigo é a criação de uma Reserva de Capital denominada Reserva das Variações da Necessidade de Capital de Giro (RVNCG como forma de garantir a manutenção do capital físico da empresa, ajustando o lucro passível de distribuição através da contabilização das variações da NCG. Esse artigo está dividido em quatro partes. Na primeira, percorremos o embasamento teórico. No desenvolvimento, segunda parte, traçamos os objetivos, as premissas e descrevemos a criação e a contabilização da RVNCG. Na terceira parte, demonstramos a proposta do artigo através de três exemplos numéricos com os respectivos Balanços Patrimoniais e Demonstrações do Resultado, mostrando a utilização proposta da RVNCG; por fim, na quarta e última parte apresentamos nossas conclusões.When we want to begin or expand an activity, the need to invest in permanent assets is profoundly analyzed, but little attention is given to the investment in clients and inventories

  3. Associação entre dois diferentes tipos de estrangulamento com a variação da pressão intraocular em atletas de jiu-jitsu

    OpenAIRE

    Scarpi,Marinho Jorge; Conte,Marcelo; Rossin,Reginaldo Alexandre; Skubs,Renato; Lenk,Rudolf Eberhard; Brant,Rodrigo

    2009-01-01

    OBJETIVO: Verificar a associação entre dois diferentes tipos de estrangulamento com a variação da pressão intraocular em atletas de jiu-jitsu. MÉTODO: Estudo observacional em grupo de 9 atletas de jiu-jitsu, com mínimo 6 meses de treinamento, sexo masculino, idades entre 20 e 30 anos, sem presença de lesões físicas e do bulbo ocular. Buscou-se associação entre a variação da pressão intraocular e os estrangulamentos Frontal da Guarda (E1) e Frontal da Montada (E2). A pressão intraocular foi de...

  4. Relação entre idade e variação da flexibilidade de bailarinas

    Directory of Open Access Journals (Sweden)

    Aline Huber da Silva

    2008-10-01

    Full Text Available O objetivo deste estudo foi verificar se o comportamento da flexibilidade, após 8 semanas de aplicação da técnica de alongamento por Facilitação Neuromuscular Proprioceptiva em bailarinas, tem relação com suas idades. A amostra foi obtida de forma intencional, composta por 11 bailarinas na faixa etária de 13 a 16 anos. Realizou-se avaliação da flexibilidade angular dos movimentos de flexão (com o joelho estendido, abdução e rotação externa do quadril através da goniometria e da flexibilidade linear com a Caixa de Sentar e Alcançar de Wells, antes e após o período experimental de oito semanas, com duas intervenções semanais, utilizando a técnica de FNP. Para análise, usou-se estatística descritiva, teste t e correlação linear de Pearson. Adotou-se significância de 5%. Somente a variação da rotação externa e da Caixa de Sentar e Alcançar, durante o período experimental, apresentaram correlação estatisticamente significativa com a idade das bailarinas, porém, essa correlação ainda assim foi bastante fraca. Pode-se perceber que praticamente não houve relação entre a variação da flexibilidade com a idade da amostra.

  5. Análise das variações anatômicas do canal da mandíbula encontradas em radiografias panorâmicas

    Directory of Open Access Journals (Sweden)

    Yza Daniella Nunes Andrade

    Full Text Available INTRODUÇÃO: No âmbito da clínica odontológica, o bloqueio do nervo alveolar inferior é o mais utilizado; todavia, diversos estudos têm mostrado as mais altas taxas de fracasso, as quais, normalmente, têm como motivo a falha na observação da posição, da forma e da anatomia dos nervos. Essas falhas decorrentes da variação anatômica do nervo alveolar inferior já vêm sendo estudadas na literatura, através de estudos com a análise de radiografias panorâmicas, como proposto neste estudo. OBJETIVO: O objetivo deste estudo foi verificar a ocorrência e a prevalência das variações anatômicas, bem como a correlação das variações do canal da mandíbula com lado e sexo, que podem ocorrer no canal mandibular, por meio de radiografias panorâmicas de pacientes atendidos no Departamento de Odontologia da Universidade Federal de Sergipe (UFS. MATERIAL E MÉTODO: Foram analisadas 1.500 radiografias panorâmicas de pacientes atendidos pelo Departamento de Odontologia da Universidade Federal de Sergipe (UFS. Imagens radiográficas foram observadas sobre um negatoscópio, utilizando-se uma máscara preta ao redor das radiografias, em ambiente com luminosidade apropriada. RESULTADO: Neste estudo, foram observados 5,3% de bifurcações do canal mandibular; 47,5% de canais altos; 16,8% de canais intermediários; 27,1% de canais baixos, e 8,6% de canais com outras variações. CONCLUSÃO: Baseando-se na altura do canal mandibular, houve maior prevalência dos canais altos do que os demais nas mulheres, sendo que não houve diferenças entre os gêneros com relação aos demais tipos e lados afetados. Na classificação dos canais bífidos, não houve diferença estatisticamente significante entre homens e mulheres. Observou-se que a maior prevalência foi para canais sem bifurcação.

  6. Pollution influence in the variability of the lichen Lecanora varia (Ehrh) ach in the area of Bratislava

    Energy Technology Data Exchange (ETDEWEB)

    Pisut, I; Jelinkova, E

    1973-01-01

    The lichen Lecanora varia was transplanted from nonpolluted areas to polluted areas in Bratislava. The morphology of the organisms changed; soredia and apothecia with a soredious margin were formed. New young ascocarp with a paler colored discus and a margin were common. The transformation is conditioned by the degree of air pollution exposure. The rate is variable, and depends considerably on macroclimatic circumstances (mainly on the quantity of precipitation in winter). 10 references, 3 figures, 5 tables.

  7. Potential trophic cascades triggered by the barred owl range expansion

    Science.gov (United States)

    Holm, Samantha R.; Noon, Barry R.; Wiens, David; Ripple, William J.

    2016-01-01

    Recently, the barred owl (Strix varia) has expanded its range into the Pacific Northwest of the United States resulting in pronounced effects on the demography and behavior of the northern spotted owl (S. occidentalis caurina). The range expansion has brought together historically allopatric species, creating the potential for significant changes in the avian predator community with possible cascading effects on food-web dynamics. The adverse effects of the barred owl on the behavior and demography of the northern spotted owl are well-documented, but little is known about the immediate and long-term effects changes in the predator community may have on native species composition and ecosystem processes. Based on northern spotted owl and barred owl selection for diet and habitat resources, there is a potential for trophic cascades within the region's predator and prey communities, differing responses by their shared and unique prey species, and possible direct and indirect effects on ecosystem processes. We explored the possible ecological consequences of the barred owl range expansion to wildlife communities of the Pacific Northwest based on the theoretical underpinnings of predator–prey relationships, interspecific competition, intraguild predation, and potential cascading trophic interactions. Negative effects on fitness of northern spotted owls because of interspecific competition with barred owls are strong selection forces that may contribute to the regional extinction of the northern spotted owl. In addition, we posit that shared prey species and those uniquely consumed by barred owls, along with other competing native predators, may experience changes in behavior, abundance, and distribution as a result of increased rates of predation by rapidly expanding populations of barred owls.

  8. EJEMPLIFICACIÓN DE UNA ESTRATEGIA METODOLÓGICA PARA CONTRIBUIR AL DESARROLLO DE COMPETENCIAS EN LA ASIGNATURA DEL CÁLCULO DE VARIAS VARIABLES

    Directory of Open Access Journals (Sweden)

    Juan Carlos Ruiz Mendoza

    2015-12-01

    Full Text Available En esta investigación se aplicó una estrategia didáctica centrada en la realización de actividades para el desarrollo de competencias formativas en el aula clase, mediante el vínculo de la teoría con la práctica, a estudiantes que ya habían cursado la asignatura del Cálculo de varias variables que se imparte en la Facultad de Ciencias Físico Matemáticas de la Universidad Autónoma de Nuevo León. Para ello se utilizó el software Cabri Plus 11 como medio para la comprensión de los temas de la asignatura, tomando en cuenta las potencialidades del proceso didáctico así como las potencialidades del Cálculo de varias variables. Se muestran los resultados parciales de la aplicación de la estrategia.

  9. Agriculture, habitat loss and spatial patterns of human occupation in a biodiversity hotspot Agricultura, perda de hábitat e padrões espaciais de ocupação humana em um "hotspot" de biodiversidade

    Directory of Open Access Journals (Sweden)

    José Alexandre Felizola Diniz-Filho

    2009-12-01

    Full Text Available The Cerrado biome, the second largest biome in Neotropical region, consists of a mosaic of different habitat types, ranging from open grasslands to dense woodlands and dry forests. An intensive recent occupation process has transformed it into the most important region for cattle ranching and intensive commodity crops in Brazil. In this study, a macroecological approach was used to evaluate broad-scale spatial patterns of habitat loss in the Brazilian Cerrado, applying a series of spatial autocorrelation and partial regression analyses to understand how the proportion of remaining natural habitats is correlated with socio-economic variables, expressing different dimensions of human occupation and climatic variation. On average, 59% of the area is occupied by natural remnants at the spatial scale analyzed, although patterns of habitat loss are strongly spatially structured, with a Moran's I spatial autocorrelation coefficient equal to 0.825 ± 0.055 (p O bioma Cerrado é o segundo maior da região Neotropical e é formado por mosaico de diferentes tipos de hábitats, desde campos abertos até florestas densas. Um recente e intensivo processo de ocupação humana tem transformado essa eco-região em uma das mais importantes regiões para agropecuária no Brasil. Uma abordagem macroecológica foi utilizada para elucidar padrões em amplas escalas espaciais de perdas de hábitat no Cerrado brasileiro, implementando técnicas de autocorrelação espacial e análises de regressão parcial para entender como a proporção de remanescentes de vegetação natural está correlacionada com variáveis socioeconômicas, expressando diferentes dimensões de ocupação humana e com variações climáticas. Em média, 59% da área é ocupada por remanescentes de vegetação, na escala da análise, mesmo que os padrões de perda de hábitat estejam fortemente estruturados no espaço, com o coeficiente de autocorrelação espacial de I de Moran igual a 0,825 ± 0

  10. Ocorrência do pólen de Podocarpus sp. (Podocarpaceae nas coletas de Frieseomelitta varia Lepeletier 1836 (Apidae: Meliponinae em uma área de Manaus, AM, Brasil Occurrence of Podocarpus sp. (Podocarpaceae pollen on Frieseomelitta varia Lepeletier 1836 (Apidae: Meliponinae in Manaus, Amazonas, Brazil

    Directory of Open Access Journals (Sweden)

    Antonio Carlos Marques-Souza

    2010-06-01

    Full Text Available Durante o período de doze meses, o pólen transportado por Frieseomelitta varia Lepeletier 1836 foi coletado das corbículas das operárias, logo após o fechamento da entrada das colméias. Feita a identificação polínica dos grãos de pólen e sua frequência mensal nas amostras, constatou-se que as espécies das famílias mais visitadas pela ordem de coleta, foram: Cecropiaceae, Sapotaceae, Myrtaceae e Moraceae. As operárias coletaram o pólen de 79 espécies de plantas distribuídas em 60 gêneros e 37 famílias, sendo as mais frequentes: Cecropia sp. visitada o ano todo com atratividade em janeiro de 82,03%, Morus sp. com atratividade de 37,46% em dezembro; Myrcia amazonica DC. com atratividade em abril de 32,34% e Pouteria macrophylla (A.DC. Eyma em junho com atratividade de 36,54%. Quanto a Podocarpus sp. esse é o primeiro relato da presença do pólen dessa espécie em coletas de meliponíneos, o que não deixa de ser um fato curioso, uma vez que se trata de uma gimnosperma encontrada em áreas específicas da região amazônica e que apresentou atratividade para Frieseomelitta varia Lepeletier 1836 de 4,94% no mês de março.Over a 12 month period, pollen was sampled from the corbiculae of workers of the stingless bee Frieseomelitta varia Lepeletier 1836. Collections were obtained immediately after sealing the hives, located in a forest fragment in the city of Manaus. Pollen was identified and monthly frequency of each type was tallied. The most-visited plant families in decreasing order of frequency were Cecropiaceae, Sapotaceae, Myrtaceae and Moraceae. Identified pollen was harvested from 79 plant species in 60 genera and 37 families. The most frequent species were: Cecropia sp., visited year-round but with highest attractiveness (82% in January; Morus sp., with peak attractiveness (37% in December; Myrcia amazonica DC. with 32% peak attractiveness in April; and Pouteria macrophylla (A.DC. Eyma, with 37% peak attractiveness in

  11. Habitats and Species Covered by the EEC Habitats Directive

    DEFF Research Database (Denmark)

    Pihl, S.; Søgaard, B.; Ejrnæs, R.

    of Conservation (SAC's), Natura 2000. The designations are based upon the presence of 60 of the natural habitat types listed in Annex I of the Directive and approx. 44 of the species listed in Annex II which occur within the territory of Denmark and for the conservation of which the Community has a special...... and the Danish county authorities have initiated a co-operative programme to provide and compile the data necessary to assess the conservation status of the natural habitat types and species concerned. The purpose of this report is to present the conservation status of the habitats and species in Denmark...

  12. Modelling Fish Habitat Suitability in the Eastern English Channel. Application to community habitat level

    OpenAIRE

    Vaz, Sandrine; Carpentier, Andre; Loots, Christophe; Koubbi, Philippe

    2004-01-01

    Valuable marine habitats and living resources can be found in the Eastern English Channel and in 2003, a Franco-British Interreg IIIA project, ‘Eastern Channel Habitat Atlas for Marine Resource Management’ (CHARM), was initiated to support decision-making for management of essential fish habitats. Fish habitat corresponds to geographic areas within which ranges of environmental factors define the presence of a particular species. Habitat Suitability index (HSI) modelling was used to relate fi...

  13. Two-dimensional physical habitat modeling of effects of habitat structures on urban stream restoration

    Directory of Open Access Journals (Sweden)

    Dongkyun Im

    2011-12-01

    Full Text Available River corridors, even if highly modified or degraded, still provide important habitats for numerous biological species, and carry high aesthetic and economic values. One of the keys to urban stream restoration is recovery and maintenance of ecological flows sufficient to sustain aquatic ecosystems. In this study, the Hongje Stream in the Seoul metropolitan area of Korea was selected for evaluating a physically-based habitat with and without habitat structures. The potential value of the aquatic habitat was evaluated by a weighted usable area (WUA using River2D, a two-dimensional hydraulic model. The habitat suitability for Zacco platypus in the Hongje Stream was simulated with and without habitat structures. The computed WUA values for the boulder, spur dike, and riffle increased by about 2%, 7%, and 131%, respectively, after their construction. Also, the three habitat structures, especially the riffle, can contribute to increasing hydraulic heterogeneity and enhancing habitat diversity.

  14. Rukopisni zbornik Varia Dalmatica (Codex Lucianus) kao svjedočanstvo humanističke književne komunikacije

    OpenAIRE

    Jovanović, Neven

    2008-01-01

    Lokalnoj književnoj komunikaciji — prepoznatljivoj, za potrebe ovog teksta, po apostrofiranju konkretnoga, stvarnog adresata — namijenjeno je 99 tekstova rukopisnog zbornika Varia Dalmatica (Zadar, Znanstvena biblioteka, sign. 25290, ms. 617). Svi su tekstovi nastali do siječnja 1614, a prepisao ih je Trogiranin Petar Lucić; samo je četiri pjesme povodom njegove smrti prepisao Petrov sin Ivan, budući glasoviti povjesničar. Tekstovi lokalne književne komunikacije većinom su pjesme (samo su dva...

  15. Variação do volume de gotas de colírios lubrificantes disponíveis no mercado brasileiro

    Directory of Open Access Journals (Sweden)

    Vitorugo Silvestre Nascimento

    Full Text Available RESUMO Objetivo: Avaliar a variação intra e interexaminadores do volume de gotas dispensados de frascos de colírios lubrificantes disponíveis no mercado. Métodos: Foram estudados cinco frascos de colírios lubrificantes e dezenove voluntários participaram deste estudo. A massa média de gotas de 20µl dos colírios foi obtida utilizando micropipeta e balança de precisão e como padrão para comparação com a massa das gotas obtidas pelos voluntários. Cinco gotas de cada frasco foram pesadas individualmente com o tubo de colírio perpendicular à balança, usando o primeiro e segundo dedos da mão direita, de forma que a pressão fosse aplicada somente no meio do frasco. Os experimentos foram realizados em uma sala climatizada a temperatura ambiente (21±1°C. Resultados: Todos os frascos de colírios apresentaram variação estatisticamente significante das massas das gotas obtidas pelos examinadores quando comparadas com a massa média padrão de 0,0182±0,0014g, com exceção da comparação entre os dados do colírio A com o colírio D, que não apresentou variação estatisticamente significante. Conclusão: O presente estudo demonstra a ausência de uniformidade das gotas dispensadas pelos frascos de colírios disponíveis no mercado e a sua inadequação à real necessidade, uma vez que as gotas dispensadas são maiores do que o indicado. Esse fato torna-se um problema quando se trata de período de tratamento prolongado, especialmente com colírios dispendiosos como os indicados para a terapêutica do glaucoma. Nesse sentido, a padronização das gotas de colírios se faz necessária.

  16. European red list of habitats. Part 1: Marine habitats

    NARCIS (Netherlands)

    Gubbay, S.; Sanders, N.; Haynes, T.; Janssen, J.A.M.; Rodwell, J.R.; Nieto, A.; Garcia Criado, M.; Beal, S.; Borg, J.

    2016-01-01

    The European Red List of Habitats provides an overview of the risk
    of collapse (degree of endangerment) of marine, terrestrial and
    freshwater habitats in the European Union (EU28) and adjacent
    regions (EU28+), based on a consistent set of categories and
    criteria, and detailed data

  17. Wildlife habitats in managed rangelands—the Great Basin of southeastern Oregon: manmade habitats.

    Science.gov (United States)

    Chris Maser; Jack Ward Thomas; Ira David Luman; Ralph. Anderson

    1979-01-01

    Manmade structures on rangelands provide specialized habitats for some species. These habitats and how they function as specialized habitat features are examined in this publication. The relationships of the wildlife of the Great Basin to such structures are detailed.

  18. Diámetro biparietal en fetos a término en varias razas de perros

    OpenAIRE

    Cahua U, Jacqueline; Quispe M, Lizeth

    2016-01-01

    El presente estudio tuvo por objetivo la determinación de la medición ecográfica cuantitativa del diámetro biparietal de fetos a término en perras. Se trabajó con 181 informes ecográficos de varias razas de perras en gestación cuyos fetos tenían menos de 210 latidos por minuto, y que fueron examinados en el consultorio de ecografía de la Clínica de Animales Menores de la Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima, Perú, entre los años 2000-2014. The pr...

  19. Variações fisiológicas da pressão do líquido cefalorraqueano na cisterna magna

    Directory of Open Access Journals (Sweden)

    A. Spina-França

    1963-03-01

    Full Text Available É feito estudo de revisão das variações fisiológicas da pressão do LCR ao nível da cisterna magna (punção suboccipital. Em relação à série de 1.500 pacientes com afecções do sistema nervoso e sem sintomatologia de hipotensão ou de hipertensão intracraniana, a pressão média normal do LCR ao nível da cisterna magna foi de 11,9 cm de água (paciente calmo, decúbito lateral horizontal. As variações fisiológicas de pressão, segundo os achados, têm como limites os valôres de 4,1 e 19,7 cm de água. Êsses valôres permitem caracterizar, para a cisterna magna, a existência de hipotensão do LCR quando a pressão fôr menor ou igual a 4 cm de água; a hipertensão é caracterizada por valores iguais ou maiores do que 20 cm de água. A pressão do LCR ao nível da cisterna magna é menor do que no fundo de saco lombar. Para série de 276 pacientes o valor médio achado para êste último nível foi de 16,7 cm de água (decúbito lateral horizontal. A diferença entre as médias foi altamente significativa. Não foram verificadas modificações da pressão do LCR ao nível da cisterna magna que pudessem ser relacionadas ao sexo. Sem que representassem dados de interêsse para a prática, foram verificadas variações ligadas à côr e à idade dos pacientes. Em média a pressão do LCR se mostrou menor entre pacientes prêtos e amarelos que entre os brancos e os mulatos. Um declínio do valor médio da pressão foi verificado à medida em que aumentava a idade dos pacientes. Êste declínio mostrou-se maior para o grupo de pacientes com idade acima de 60 anos.

  20. Variação da densidade básica da madeira de progênies de Eucalyptus urophylla em dois locais.

    Directory of Open Access Journals (Sweden)

    Maria Aparecida Mourão Brasil

    2009-09-01

    Full Text Available Normal 0 21 false false false MicrosoftInternetExplorer4 Estudou-se neste trabalho a variação da densidade básica da madeira entre procedências e progênies de eucalipto plantados em duas localidades. As progênies de Eucalyptus urophylla originárias da ilha de Timor na Indonésia foram plantadas em Belo Oriente (MG e Linhares (ES no delineamento de blocos compactos em famílias (compact family blocks com 3 repetições no espaçamento de 3,0 x 2,0m. Após 4 anos as  árvores  foram amostradas ao nível do DAP com a sonda Pressler e sua densidade básica determinada pelo método do máximo teor de umidade. Os resultados mostraram que as progênies tiveram  comportamento similar nos dois locais. A maior variação entre progênies ocorreu naquelas provenientes da região Oebaha II. Os valores médios de densidade básica* das progênies não foram diferentes das procedências brasileiras utilizadas como testemunhas no experimento.

  1. A NEW HABITAT CLASSIFICATION AND MANUAL FOR STANDARDIZED HABITAT MAPPING

    Directory of Open Access Journals (Sweden)

    A. KUN

    2007-01-01

    Full Text Available Today the documentation of natural heritage with scientific methods but for conservation practice – like mapping of actual vegetation – becomes more and more important. For this purpose mapping guides containing only the names and descriptions of vegetation types are not sufficient. Instead, new, mapping-oriented vegetation classification systems and handbooks are needed. There are different standardised systems fitted to the characteristics of a region already published and used successfully for surveying large territories. However, detailed documentation of the aims and steps of their elaboration is still missing. Here we present a habitat-classification method developed specifically for mapping and the steps of its development. Habitat categories and descriptions reflect site conditions, physiognomy and species composition as well. However, for species composition much lower role was given deliberately than in the phytosociological systems. Recognition and mapping of vegetation types in the field is highly supported by a definition, list of subtypes and list of ‘types not belonging to this habitat category’. Our system is two-dimensional: the first dimension is habitat type, the other is naturalness based habitat quality. The development of the system was conducted in two steps, over 200 mappers already tested it over 7000 field days in different projects.

  2. Habitat Ecology Visual Surveys of Demersal Fishes and Habitats off California

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Since 1992, the Habitat Ecology team has been conducting fishery independent, visual surveys of demersal fishes and associated habitats in deep water (20 to 900...

  3. Nomenklaturno-fitocenološka revizija asocijacije Calamagrostio variae-Piceetum dinaricum Bertović 1975 nom. illeg. u Hrvatskoj

    OpenAIRE

    Vukelić, Joso; Alegro, Antun; Šegota, Vedran; Šapić, Irena

    2010-01-01

    U široj okolici Zavižana na sjevernom Velebitu, S. Bertović je (1975) opisao smrekovu asocijaciju sa šarenkastom šašuljicom (Calamagro­stio variae-Piceetum dinaricum Bertović 1975). Naziv je asocijacije nelegiti­man (čl. 31. i 34a, Međunarodni kodeks fitocenološke nomenklature /ICPN/, Weber, Moravec i Theurillat 2000) pa je u radu naziv promijenjen u Hyperico grisebachii-Piceetum abietis (Bertović 1975) nom. nov. hoc loco i tako nomen­katurno revidiran. Osim toga, fitocenoza je istražena na š...

  4. A bio-indicator for the evaluation of quality forestry and landscape fragmentation

    Directory of Open Access Journals (Sweden)

    Kappers EF

    2013-11-01

    Full Text Available A bio-indicator for the evaluation of quality forestry and landscape fragmentation. Intensive agricultural practices, as well as tourism development, summer fires, urbanization and air pollution represent a serious threat for many woodlands in Mediterranean Europe. Tawny owls, Strix aluco, is a valuable indicator of habitat quality and shows high sensitivity to wood fragmentation. Assessing the association between Tawny owls and their habitat may provide useful tools for conservation and management of forested habitats. Populations of woodland birds are influenced by forest characteristics, wood proportion being a key factor explaining breeding density and regularity in nest spacing. Populations of the Tawny Owl reach their highest densities in old deciduous forests. The distribution of territories remains almost constant for many years, and the period during which any particular wood maintains suitable conditions for nesting depends on factors like tree species and management, especially on the timing and extent of thinning. To assure the maintenance of good habitat quality in most woodlands, regulation of water diversion, prevention of summer fires, and a general reduction of human activities inside forests seem to be useful conservation tools.

  5. Long-term habitat changes in a protected area: Implications for herpetofauna habitat management and restoration.

    Directory of Open Access Journals (Sweden)

    Chantel E Markle

    Full Text Available Point Pelee National Park, located at the southern-most tip of Canada's mainland, historically supported a large number of herpetofauna species; however, despite nearly a century of protection, six snake and five amphibian species have disappeared, and remaining species-at-risk populations are thought to be in decline. We hypothesized that long-term changes in availability and distribution of critical habitat types may have contributed to the disappearance of herpetofauna. To track habitat changes we used aerial image data spanning 85 years (1931-2015 and manually digitized and classified image data using a standardized framework. Change-detection analyses were used to evaluate the relative importance of proportionate loss and fragmentation of 17 habitat types. Marsh habitat diversity and aquatic connectivity has declined since 1931. The marsh matrix transitioned from a graminoid and forb shallow marsh interspersed with water to a cattail dominated marsh, altering critical breeding, foraging, and overwintering habitat. Reduced diversity of marsh habitats appears to be linked to the expansion of invasive Phragmites australis, which invaded prior to 2000. Loss of open habitats such as savanna and meadow has reduced availability of high quality thermoregulation habitat for reptiles. Restoration of the northwestern region and tip of Point Pelee National Park to a mixed landscape of shallow wetlands (cattail, graminoid, forb, open water and eradication of dense Phragmites stands should improve habitat diversity. Our results suggest that long-term landscape changes resulting from habitat succession and invasive species can negatively affect habitat suitability for herpetofauna and protection of land alone does not necessarily equate to protection of sensitive herpetofauna.

  6. Long-term habitat changes in a protected area: Implications for herpetofauna habitat management and restoration.

    Science.gov (United States)

    Markle, Chantel E; Chow-Fraser, Gillian; Chow-Fraser, Patricia

    2018-01-01

    Point Pelee National Park, located at the southern-most tip of Canada's mainland, historically supported a large number of herpetofauna species; however, despite nearly a century of protection, six snake and five amphibian species have disappeared, and remaining species-at-risk populations are thought to be in decline. We hypothesized that long-term changes in availability and distribution of critical habitat types may have contributed to the disappearance of herpetofauna. To track habitat changes we used aerial image data spanning 85 years (1931-2015) and manually digitized and classified image data using a standardized framework. Change-detection analyses were used to evaluate the relative importance of proportionate loss and fragmentation of 17 habitat types. Marsh habitat diversity and aquatic connectivity has declined since 1931. The marsh matrix transitioned from a graminoid and forb shallow marsh interspersed with water to a cattail dominated marsh, altering critical breeding, foraging, and overwintering habitat. Reduced diversity of marsh habitats appears to be linked to the expansion of invasive Phragmites australis, which invaded prior to 2000. Loss of open habitats such as savanna and meadow has reduced availability of high quality thermoregulation habitat for reptiles. Restoration of the northwestern region and tip of Point Pelee National Park to a mixed landscape of shallow wetlands (cattail, graminoid, forb, open water) and eradication of dense Phragmites stands should improve habitat diversity. Our results suggest that long-term landscape changes resulting from habitat succession and invasive species can negatively affect habitat suitability for herpetofauna and protection of land alone does not necessarily equate to protection of sensitive herpetofauna.

  7. Habitat Blocks and Wildlife Corridors

    Data.gov (United States)

    Vermont Center for Geographic Information — Habitat blocks are areas of contiguous forest and other natural habitats that are unfragmented by roads, development, or agriculture. Vermonts habitat blocks are...

  8. 75 FR 34975 - Notice of Estuary Habitat Restoration Council's Intent to Revise its Estuary Habitat Restoration...

    Science.gov (United States)

    2010-06-21

    ... Estuary Habitat Restoration Council's Intent to Revise its Estuary Habitat Restoration Strategy; Request... interagency Estuary Habitat Restoration Council, is providing notice of the Council's intent to revise the ''Estuary Habitat Restoration Strategy'' and requesting public comments to guide its revision. DATES...

  9. Vacant habitats in the Universe.

    Science.gov (United States)

    Cockell, Charles S

    2011-02-01

    The search for life on other planets usually makes the assumption that where there is a habitat, it will contain life. On the present-day Earth, uninhabited habitats (or vacant habitats) are rare, but might occur, for example, in subsurface oils or impact craters that have been thermally sterilized in the past. Beyond Earth, vacant habitats might similarly exist on inhabited planets or on uninhabited planets, for example on a habitable planet where life never originated. The hypothesis that vacant habitats are abundant in the Universe is testable by studying other planets. In this review, I discuss how the study of vacant habitats might ultimately inform an understanding of how life has influenced geochemical conditions on Earth. Copyright © 2010 Elsevier Ltd. All rights reserved.

  10. Modos em vigas com secção transversal de variação linear

    OpenAIRE

    Jovita Rasch Bracht Juver

    2002-01-01

    O objetivo principal deste trabalho é a obtenção dos modos e as freqüências naturais de vigas de variação linear e em forma de cunha, com condições de contorno clássicas e não-clássicas, descritas pelo modelo estrutural de Euler-Bernoulli. A forma dos modos foi determinado com o uso das funções cilíndricas. No caso forçado se considera uma força harmônica e se resolve o problema pelo método espectral, utuilizando o software simbólico Maple V5. Realiza-se uma análise comparativa dos resultados...

  11. Ajuste do rendimento para a variação do estande em experimentos de melhoramento genético do feijão Adjustment of the yield for the stand variation in common bean genetic breeding experiments

    Directory of Open Access Journals (Sweden)

    Clause Fátima de Brum Piana

    2007-12-01

    Full Text Available O objetivo deste trabalho foi avaliar o ajuste do rendimento pela variação do estande em experimentos de feijão e propor procedimento para ajustamento por análise de co-variação. Utilizaram-se dados de 33 ambientes do Ensaio Estadual de Feijão do Rio Grande do Sul. Realizaram-se as análises de variação e de co-variação de rendimento e de estande em cada ambiente. Foram considerados quatro modelos de ajustamento alternativos: sem ajuste para a variação do estande; com ajuste para o estande médio geral; com ajuste para os estandes médios dos genótipos; e com ajuste para os estandes médios dos grupos de genótipos. Em 70% dos ambientes, ocorreu efeito linear ou quadrático significativo de estande sobre rendimento e em 85% efeito significativo de genótipo sobre estande. O efeito compensatório manifestou-se com diferentes intensidades nos ambientes. O ajuste do rendimento para a variação do estande, considerando o efeito de genótipos sobre o estande, é importante em ensaios de melhoramento do feijão. É necessário o registro de informações que permitam discriminar a origem da variação do estande.The objective of this work was to evaluate the adjustment of the yield for the stand in common bean experiments and to propose a procedure for the adjustment through covariance analysis. Data from 33 environments of the Common Bean Assay of Rio Grande do Sul State, Brazil, were used. Variance and covariance analyses of yield and stand were proceeded for each environment. Four alternative models were considered: without adjustment for stand; with adjustment for the average stand; with adjustment for the genotypes average stand; and with adjustment for the groups of genotypes average stand. Significant linear or quadratic effects of stand on yield occurred in 70% of the environments and of genotype on stand in 85%. The compensatory effect was manifested with different intensities in the environments. The adjustment of the yield

  12. Habitat quality influences population distribution, individual space use and functional responses in habitat selection by a large herbivore.

    Science.gov (United States)

    Bjørneraas, Kari; Herfindal, Ivar; Solberg, Erling Johan; Sæther, Bernt-Erik; van Moorter, Bram; Rolandsen, Christer Moe

    2012-01-01

    Identifying factors shaping variation in resource selection is central for our understanding of the behaviour and distribution of animals. We examined summer habitat selection and space use by 108 Global Positioning System (GPS)-collared moose in Norway in relation to sex, reproductive status, habitat quality, and availability. Moose selected habitat types based on a combination of forage quality and availability of suitable habitat types. Selection of protective cover was strongest for reproducing females, likely reflecting the need to protect young. Males showed strong selection for habitat types with high quality forage, possibly due to higher energy requirements. Selection for preferred habitat types providing food and cover was a positive function of their availability within home ranges (i.e. not proportional use) indicating functional response in habitat selection. This relationship was not found for unproductive habitat types. Moreover, home ranges with high cover of unproductive habitat types were larger, and smaller home ranges contained higher proportions of the most preferred habitat type. The distribution of moose within the study area was partly related to the distribution of different habitat types. Our study shows how distribution and availability of habitat types providing cover and high-quality food shape ungulate habitat selection and space use.

  13. Conservation of ParaHox genes' function in patterning of the digestive tract of the marine gastropod Gibbula varia

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    Steiner Gerhard

    2010-07-01

    Full Text Available Abstract Background Presence of all three ParaHox genes has been described in deuterostomes and lophotrochozoans, but to date one of these three genes, Xlox has not been reported from any ecdysozoan taxa and both Xlox and Gsx are absent in nematodes. There is evidence that the ParaHox genes were ancestrally a single chromosomal cluster. Colinear expression of the ParaHox genes in anterior, middle, and posterior tissues of several species studied so far suggest that these genes may be responsible for axial patterning of the digestive tract. So far, there are no data on expression of these genes in molluscs. Results We isolated the complete coding sequences of the three Gibbula varia ParaHox genes, and then tested their expression in larval and postlarval development. In Gibbula varia, the ParaHox genes participate in patterning of the digestive tract and are expressed in some cells of the neuroectoderm. The expression of these genes coincides with the gradual formation of the gut in the larva. Gva-Gsx patterns potential neural precursors of cerebral ganglia as well as of the apical sensory organ. During larval development this gene is involved in the formation of the mouth and during postlarval development it is expressed in the precursor cells involved in secretion of the radula, the odontoblasts. Gva-Xolx and Gva-Cdx are involved in gut patterning in the middle and posterior parts of digestive tract, respectively. Both genes are expressed in some ventral neuroectodermal cells; however the expression of Gva-Cdx fades in later larval stages while the expression of Gva-Xolx in these cells persists. Conclusions In Gibbula varia the ParaHox genes are expressed during anterior-posterior patterning of the digestive system. This colinearity is not easy to spot during early larval stages because the differentiated endothelial cells within the yolk permanently migrate to their destinations in the gut. After torsion, Gsx patterns the mouth and foregut

  14. Habitat loss and gain: Influence on habitat attractiveness for estuarine fish communities

    Science.gov (United States)

    Amorim, Eva; Ramos, Sandra; Elliott, Michael; Franco, Anita; Bordalo, Adriano A.

    2017-10-01

    Habitat structure and complexity influence the structuring and functioning of fish communities. Habitat changes are one of the main pressures affecting estuarine systems worldwide, yet the degree and rate of change and its impact on fish communities is still poorly understood. In order to quantify historical modifications in habitat structure, an ecohydrological classification system using physiotopes, i.e. units with homogenous abiotic characteristics, was developed for the lower Lima estuary (NW Portugal). Field data, aerial imagery, historical maps and interpolation methods were used to map input variables, including bathymetry, substratum (hard/soft), sediment composition, hydrodynamics (current velocity) and vegetation coverage. Physiotopes were then mapped for the years of 1933 and 2013 and the areas lost and gained over the 80 years were quantified. The implications of changes for the benthic and demersal fish communities using the lower estuary were estimated using the attractiveness to those communities of each physiotope, while considering the main estuarine habitat functions for fish, namely spawning, nursery, feeding and refuge areas and migratory routes. The lower estuary was highly affected due to urbanisation and development and, following a port/harbour expansion, its boundary moved seaward causing an increase in total area. Modifications led to the loss of most of its sandy and saltmarsh intertidal physiotopes, which were replaced by deeper subtidal physiotopes. The most attractive physiotopes for fish (defined as the way in which they supported the fish ecological features) decreased in area while less attractive ones increased, producing an overall lower attractiveness of the studied area in 2013 compared to 1933. The implications of habitat alterations for the fish using the estuary include potential changes in the nursery carrying capacity and the functioning of the fish community. The study also highlighted the poor knowledge of the impacts of

  15. Variação lingüística e alfabetização: um estudo com crianças da primeira série do ensino fundamental

    Directory of Open Access Journals (Sweden)

    Sylvia Domingos Barrera

    Full Text Available A pesquisa teve como objetivo investigar a influência da variação lingüística sobre a aquisição da linguagem escrita. Participaram da pesquisa 65 alunos de três classes da primeira série de uma escola pública de ensino fundamental. O material utilizado para avaliar o nível de variação lingüística das crianças foi aplicado no início do ano escolar. As provas utilizadas para avaliar os níveis de leitura e escrita foram aplicadas no início e final do ano letivo. A análise estatística mostrou correlação negativa significativa entre os níveis iniciais de variação lingüística e o desempenho final das crianças em leitura, sugerindo que a utilização de linguagem não-padrão pelos alunos pode dificultar o processo de alfabetização, sobretudo quando não trabalhada adequadamente pelas professoras. Os resultados obtidos sugerem a importância de uma efetiva difusão dos conhecimentos lingüísticos e sociolingüísticos, através dos cursos de formação de professores alfabetizadores.

  16. Variação anatômica radial do lenho de açoita-cavalo (Luehea divaricata) e sua influência na densidade aparente. Radial variation of wood anatomy in açoita-cavalo (Luehea divaricata) and its influence on the specific gravity.

    OpenAIRE

    Eduardo Luiz LONGUI; Israel Luiz de LIMA; Sandra Monteiro Borges FLORSHEIM; Alaor BUFOLO

    2009-01-01

    Variações entre as dimensões e frequênciasdas células da madeira existem entre espéciesdiferentes, entre indivíduos da mesma espécie ouainda dentro da mesma árvore nas direções radial eaxial. Essa variação influencia diretamente nadensidade aparente e consequentemente no uso dasdiferentes madeiras. O presente estudo determinoua variação anatômica radial e sua influência nadensidade aparente no lenho de árvores de Luehea divaricata, a partir de amostras coletadas no DAP,por meio de método dest...

  17. Anopheline larval habitats seasonality and species distribution: a prerequisite for effective targeted larval habitats control programmes.

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    Eliningaya J Kweka

    Full Text Available Larval control is of paramount importance in the reduction of malaria vector abundance and subsequent disease transmission reduction. Understanding larval habitat succession and its ecology in different land use managements and cropping systems can give an insight for effective larval source management practices. This study investigated larval habitat succession and ecological parameters which influence larval abundance in malaria epidemic prone areas of western Kenya.A total of 51 aquatic habitats positive for anopheline larvae were surveyed and visited once a week for a period of 85 weeks in succession. Habitats were selected and identified. Mosquito larval species, physico-chemical parameters, habitat size, grass cover, crop cycle and distance to nearest house were recorded. Polymerase chain reaction revealed that An. gambiae s.l was the most dominant vector species comprised of An.gambiae s.s (77.60% and An.arabiensis (18.34%, the remaining 4.06% had no amplification by polymerase chain reaction. Physico-chemical parameters and habitat size significantly influenced abundance of An. gambiae s.s (P = 0.024 and An. arabiensis (P = 0.002 larvae. Further, larval species abundance was influenced by crop cycle (P≤0.001, grass cover (P≤0.001, while distance to nearest houses significantly influenced the abundance of mosquito species larvae (r = 0.920;P≤0.001. The number of predator species influenced mosquito larval abundance in different habitat types. Crop weeding significantly influenced with the abundance of An.gambiae s.l (P≤0.001 when preceded with fertilizer application. Significantly higher anopheline larval abundance was recorded in habitats in pasture compared to farmland (P = 0.002. When habitat stability and habitat types were considered, hoof print were the most productive followed by disused goldmines.These findings suggest that implementation of effective larval control programme should be targeted with larval

  18. Influência da variação da liquidez na precificação de ativos: análise em painel do mercado brasileiro no período de janeiro de 2000 a junho de 2008

    Directory of Open Access Journals (Sweden)

    Kelmara Mendes Vieira

    2011-01-01

    Full Text Available A influência da liquidez para o retorno dos ativos vem sendo amplamente pesquisada nos últimos anos, tanto do ponto de vista dos ativos individuais quanto do ponto de vista da liquidez de mercado. Este trabalho tem por objetivo principal avaliar a influência da variação da liquidez na precificação das ações. Como medidas de liquidez foram utilizadas as variações na quantidade de títulos, na quantidade de negócios e no volume financeiro, bem como estas variáveis ponderadas pelo índice Bovespa e também estas variáveis defasadas. A amostra é composta pelas ações negociadas na Bolsa de Valores de São Paulo. Foram coletados dados mensais para o período de janeiro de 2000 a junho de 2008. Os resultados mostraram que o retorno dos ativos é influenciado positivamente pelo retorno do índice Bovespa e pelas variações de liquidez. Geralmente, são as empresas com menores níveis de liquidez que apresentam as maiores variações positivas da própria liquidez e, consequentemente, terão retornos mais elevados.

  19. Habitat specialization through germination cueing: a comparative study of herbs from forests and open habitats.

    Science.gov (United States)

    Ten Brink, Dirk-Jan; Hendriksma, Harmen Pieter; Bruun, Hans Henrik

    2013-02-01

    This study examined the adaptive association between seed germination ecology and specialization to either forest or open habitats across a range of evolutionary lineages of seed plants, in order to test the hypotheses that (1) species' specialization to open vs. shaded habitats is consistently accompanied by specialization in their regeneration niche; and (2) species are thereby adapted to utilize different windows of opportunity in time (season) and space (habitat). Seed germination response to temperature, light and stratification was tested for 17 congeneric pairs, each consisting of one forest species and one open-habitat species. A factorial design was used with temperature levels and diurnal temperature variation (10 °C constant, 15-5 °C fluctuating, 20 °C constant, 25-15 °C fluctuating), and two light levels (light and darkness) and a cold stratification treatment. The congeneric species pair design took phylogenetic dependence into account. Species from open habitats germinated better at high temperatures, whereas forest species performed equally well at low and high temperatures. Forest species tended to germinate only after a period of cold stratification that could break dormancy, while species from open habitats generally germinated without cold stratification. The empirically derived germination strategies correspond quite well with establishment opportunities for forest and open-habitat plant species in nature. Annual changes in temperature and light regime in temperate forest delimit windows of opportunity for germination and establishment. Germination strategies of forest plants are adaptations to utilize such narrow windows in time. Conversely, lack of fit between germination ecology and environment may explain why species of open habitats generally fail to establish in forests. Germination strategy should be considered an important mechanism for habitat specialization in temperate herbs to forest habitats. The findings strongly suggest that

  20. California Condor Critical Habitat

    Data.gov (United States)

    California Natural Resource Agency — These Data identify (in general) the areas where critical habitat for the California Condor occur. Critical habitat for the species consists of the following 10...

  1. Headwater Stream Management Dichotomies: Local Amphibian Habitat vs. Downstream Fish Habitat

    Science.gov (United States)

    Jackson, C. R.

    2002-12-01

    Small headwater streams in mountainous areas of the Pacific Northwest often do not harbor fish populations because of low water depth and high gradients. Rather, these streams provide habitat for dense assemblages of stream-dwelling amphibians. A variety of management goals have been suggested for such streams such as encouraging large woody debris recruitment to assist in sediment trapping and valley floor formation, encouraging large woody debris recruitment to provide downstream wood when debris flows occur, providing continuous linear stream buffers within forest harvest areas to provide shade and bank stability, etc. A basic problem with analying the geomorphic or biotic benefits of any of these strategies is the lack of explicit management goals for such streams. Should managers strive to optimize downstream fish habitat, local amphibian habitat, or both? Through observational data and theoretical considerations, it will be shown that these biotic goals will lead to very different geomorphic management recommendations. For instance, woody debris greater than 60 cm diameter may assist in valley floor development, but it is likely to create subsurface channel flow of unknown value to amphibians. Trapping and retention of fine sediments within headwater streams may improve downstream spawning gravels, but degrades stream-dwelling amphibian habitat. In response to the need for descriptive information on habitat and channel morphology specific to small, non-fish-bearing streams in the Pacific Northwest, morphologies and wood frequencies in forty-two first- and second-order forested streams less than four meters wide were surveyed. Frequencies and size distributions of woody debris were compared between small streams and larger fish-bearing streams as well as between second-growth and virgin timber streams. Statistical models were developed to explore dominant factors affecting channel morphology and habitat. Findings suggest geomorphological relationships

  2. L-Reactor Habitat Mitigation Study

    International Nuclear Information System (INIS)

    1988-02-01

    The L-Reactor Fish and Wildlife Resource Mitigation Study was conducted to quantify the effects on habitat of the L-Reactor restart and to identify the appropriate mitigation for these impacts. The completed project evaluated in this study includes construction of a 1000 acre reactor cooling reservoir formed by damming Steel Creek. Habitat impacts identified include a loss of approximately 3,700 average annual habitat units. This report presents a mitigation plan, Plan A, to offset these habitat losses. Plan A will offset losses for all species studied, except whitetailed deer. The South Carolina Wildlife and Marine Resources Department strongly recommends creation of a game management area to provide realistic mitigation for loss of deer habitats. 10 refs., 5 figs., 3 tabs

  3. Focusing on variation: methods and applications of the concept of beta diversity in aquatic ecosystems Focando na variação: métodos e aplicações do conceito de diversidade beta em ecossistemas aquáticos

    Directory of Open Access Journals (Sweden)

    Adriano Sanches Melo

    2011-09-01

    Full Text Available Ecologists usually estimate means, but devote much less attention to variation. The study of variation is a key aspect to understand natural systems and to make predictions regarding them. In community ecology, most studies focus on local species diversity (alpha diversity, but only in recent decades have ecologists devoted proper attention to variation in community composition among sites (beta diversity. This is in spite of the fact that the first attempts to estimate beta diversity date back to the pioneering work by Koch and Whittaker in the 1950s. Progress in the last decade has been made in the development both of methods and of hypotheses about the origin and maintenance of variation in community composition. For instance, methods are available to partition total diversity in a region (gamma diversity, in a local component (alpha, and several beta diversities, each corresponding to one scale in a hierarchy. The popularization of the so-called raw-data approach (based on partial constrained ordination techniques and the distance-based approach (based on correlation of dissimilarity/distance matrices have allowed many ecologists to address current hypotheses about beta diversity patterns. Overall, these hypotheses are based on niche and neutral theory, accounting for the relative roles of environmental and spatial processes (or a combination of them in shaping metacommunities. Recent studies have addressed these issues on a variety of spatial and temporal scales, habitats and taxonomic groups. Moreover, life history and functional traits of species such as dispersal abilities and rarity have begun to be considered in studies of beta diversity. In this article we briefly review some of these new tools and approaches developed in recent years, and illustrate them by using case studies in aquatic ecosystems.Ecólogos geralmente estimam médias, mas dedicam pouca atenção à variação. O estudo da variação é um aspecto chave para entender

  4. Coastal Critical Habitat Designations

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Endangered Species Act (ESA) requires the Federal government to designate critical habitat, areas of habitat essential to the species' conservation, for ESA...

  5. New England wildlife: management forested habitats

    Science.gov (United States)

    Richard M. DeGraaf; Mariko Yamasaki; William B. Leak; John W. Lanier

    1992-01-01

    Presents silvicultural treatments for six major cover-type groups in New England to produce stand conditions that provide habitat opportunities for a wide range of wildlife species. Includes matrices for species occurrence and utilization by forested and nonforested habitats, habitat breadth and size class, and structural habitat features for the 338 wildlife species...

  6. Código para imageamento indireto de estrelas em sistemas binarios: simulação de variações elipsoidais e do perfil das linhas

    Science.gov (United States)

    Souza, T. R.; Baptista, R.

    2003-08-01

    As estrelas secundárias em variáveis cataclí smicas (VCs) e binárias-x de baixa massa (BXBMs) são cruciais para o entendimento da origem, evolução e comportamento destas binárias interagentes. Elas são estrelas magneticamente ativas submetidas a condições ambientais extremas [e.g., estão muito próximas de uma fonte quente e irradiante; têm rotação extremamente rápida e forma distorcida; estão perdendo massa a taxas de 10-8-10-10 M¤/ano] que contribuem para que suas propriedades sejam distintas das de estrelas de mesma massa na seqüência principal. Por outro lado, o padrão de irradiação na face da secundária fornece informação sobre a geometria das estruturas de acréscimo em torno da estrela primária. Assim, a obtenção de imagens da superfície destas estrelas é de grande interesse astrofísico. A Tomografia Roche usa as variações no perfil das linhas de emissão/absorção da estrela secundária em função da fase orbital para mapear a distribuição de brilho em sua superfície. Neste trabalho apresentamos os resultados iniciais do desenvolvimento de um programa para o mapeamento da distribuição de brilho na superfí cie das estrelas secundárias em VCs e BXBMs com técnicas de astro-tomografia. Presentemente temos em operação um código que simula as variações no perfil das linhas em conseqüência de efeito Doppler resultante da combinação de rotação e translação de uma estrela em forma de lobo de Roche em torno do centro de massa da binária, em função da distribuição de brilho na superfície desta estrela. O código igualmente produz a curva de luz resultante das variações de aspecto da estrela em função da fase orbital (variações elipsoidais).

  7. Wildlife habitat considerations

    Science.gov (United States)

    Helen Y. Smith

    2000-01-01

    Fire, insects, disease, harvesting, and precommercial thinning all create mosaics on Northern Rocky Mountain landscapes. These mosaics are important for faunal habitat. Consequently, changes such as created openings or an increase in heavily stocked areas affect the water, cover, and food of forest habitats. The “no action” alternative in ecosystem management of low...

  8. Mechanisms Affecting Population Density in Fragmented Habitat

    Directory of Open Access Journals (Sweden)

    Lutz Tischendorf

    2005-06-01

    Full Text Available We conducted a factorial simulation experiment to analyze the relative importance of movement pattern, boundary-crossing probability, and mortality in habitat and matrix on population density, and its dependency on habitat fragmentation, as well as inter-patch distance. We also examined how the initial response of a species to a fragmentation event may affect our observations of population density in post-fragmentation experiments. We found that the boundary-crossing probability from habitat to matrix, which partly determines the emigration rate, is the most important determinant for population density within habitat patches. The probability of crossing a boundary from matrix to habitat had a weaker, but positive, effect on population density. Movement behavior in habitat had a stronger effect on population density than movement behavior in matrix. Habitat fragmentation and inter-patch distance may have a positive or negative effect on population density. The direction of both effects depends on two factors. First, when the boundary-crossing probability from habitat to matrix is high, population density may decline with increasing habitat fragmentation. Conversely, for species with a high matrix-to-habitat boundary-crossing probability, population density may increase with increasing habitat fragmentation. Second, the initial distribution of individuals across the landscape: we found that habitat fragmentation and inter-patch distance were positively correlated with population density when individuals were distributed across matrix and habitat at the beginning of our simulation experiments. The direction of these relationships changed to negative when individuals were initially distributed across habitat only. Our findings imply that the speed of the initial response of organisms to habitat fragmentation events may determine the direction of observed relationships between habitat fragmentation and population density. The time scale of post

  9. Sound solutions for habitat monitoring

    Science.gov (United States)

    Mary M. Rowland; Lowell H. Suring; Christina D. Vojta

    2015-01-01

    For agencies and organizations to effectively manage wildlife, knowledge about the status and trend of wildlife habitat is critical. Traditional wildlife monitoring, however, has focused on populations rather than habitat, because ultimately population status drives long-term species viability. Still, habitat loss has contributed to the decline of nearly all at-risk...

  10. Crescimento alométrico, morfologia e uso do habitat em cinco espécies de Mabuya Fitzinger (Reptilia, Scincidae Allometric growth, morphology and habitat use in five species of Mabuya Fitzinger (Reptilia, Scincidae

    Directory of Open Access Journals (Sweden)

    Gabriel Silva Pinto

    2004-06-01

    Full Text Available Foram analisadas a variação ontogenética da forma do corpo nos lagartos sul-americanos Mabuya agilis, M. bistriata, M. guaporicola, M. macrorhyncha e M. nigropunctata, assim como as diferenças interespecíficas nas proporções do corpo, como resultados de um possível crescimento alométrico. As trajetórias das tendências ontogenéticas foram significativamente diferentes somente entre M. guaporicola e M. nigropunctata; todos os pares de espécies, exceto M. agilis e M. macrorhyncha, M. bistriata e M. nigropunctata, demonstraram diferenças significativas em relação ao intercepto Y. A Análise de Componentes Principais aplicada sobre uma série de caracteres morfométricos demonstrou sinais opostos para as variáveis do corpo e dos membros, corroborando estudos anteriores. Contudo, quando as espécies foram analisadas individualmente, as mãos e dígitos apresentaram alometria negativa, enquanto os demais segmentos apresentaram variação em suas alometrias. Algumas hipóteses levantadas nesse estudo, relacionadas à forma do corpo e ao uso do hábitat nessas espécies, necessitam ser testadas.The ontogenetic variation of body shape in the South American skinks Mabuya agilis Boulenger, 1887, M. bistriata (Spix, 1825, M. guaporicola Dunn, 1936, M. macrorhyncha Hoge, 1946, and M. nigropunctata (Spix, 1825 were analyzed. Interspecific differences in body proportions as a possible result of allometric growth in these species are also examined. Ontogenetic trend lines were significantly different only between M. guaporicola and M. nigropunctata; all other species pairs, except M. agilis and M. macrorhyncha, M. bistriata and M. nigropunctata, showed significantly different Y intercepts. A PCA analysis on a series of morphometric characters showed opposite signals for body and limb variables, corroborating previous studies. However, when the species were analyzed separately, hand and digits were the most likely segments to present negative

  11. Indicators: Physical Habitat Complexity

    Science.gov (United States)

    Physical habitat complexity measures the amount and variety of all types of cove at the water’s edge in lakes. In general, dense and varied shoreline habitat is able to support more diverse communities of aquatic life.

  12. 3.10. Habitat restoration and creation

    OpenAIRE

    2016-01-01

    1.12.1 Terrestrial habitat Based on the collated evidence, what is the current assessment of the effectiveness of interventions for terrestrial habitat restoration and creation? Beneficial ● Replant vegetation Likely to be beneficial ● Clear vegetation● Create artificial hibernacula or aestivation sites● Create refuges● Restore habitat connectivity Unknown effectiveness (limited evidence) ● Change mowing regime No evidence found (no assessment) ● Create habitat connectivity Beneficial Repla...

  13. Habitat Heterogeneity Variably Influences Habitat Selection by Wild Herbivores in a Semi-Arid Tropical Savanna Ecosystem.

    Directory of Open Access Journals (Sweden)

    Victor K Muposhi

    Full Text Available An understanding of the habitat selection patterns by wild herbivores is critical for adaptive management, particularly towards ecosystem management and wildlife conservation in semi arid savanna ecosystems. We tested the following predictions: (i surface water availability, habitat quality and human presence have a strong influence on the spatial distribution of wild herbivores in the dry season, (ii habitat suitability for large herbivores would be higher compared to medium-sized herbivores in the dry season, and (iii spatial extent of suitable habitats for wild herbivores will be different between years, i.e., 2006 and 2010, in Matetsi Safari Area, Zimbabwe. MaxEnt modeling was done to determine the habitat suitability of large herbivores and medium-sized herbivores. MaxEnt modeling of habitat suitability for large herbivores using the environmental variables was successful for the selected species in 2006 and 2010, except for elephant (Loxodonta africana for the year 2010. Overall, large herbivores probability of occurrence was mostly influenced by distance from rivers. Distance from roads influenced much of the variability in the probability of occurrence of medium-sized herbivores. The overall predicted area for large and medium-sized herbivores was not different. Large herbivores may not necessarily utilize larger habitat patches over medium-sized herbivores due to the habitat homogenizing effect of water provisioning. Effect of surface water availability, proximity to riverine ecosystems and roads on habitat suitability of large and medium-sized herbivores in the dry season was highly variable thus could change from one year to another. We recommend adaptive management initiatives aimed at ensuring dynamic water supply in protected areas through temporal closure and or opening of water points to promote heterogeneity of wildlife habitats.

  14. Variação sazonal da fotossíntese e clorofila em progênies de Grevillea robusta Cunn

    OpenAIRE

    Inoue, Mario Takao; UNICENTRO; Martins, Emerson Gonçalves; EMBRAPA

    2009-01-01

    Avaliou-se a fotossíntese e o teor de clorofila em seis progênies de Grevillea robusta Cunn. durante um ano, visando detectar possíveis variações sazonais. As progênies demonstraram reações distintas entre si e entre as estações do ano, sugerindo que as grandezas fisiológicas podem servir como indicadores do comportamento genético aos quatro anos de idade das progênies testadas. A fotossíntese elevou-se no sentido do inverno para primavera e verão, para decair no sentido do outono-inverno. A ...

  15. Caracterização do lenho e variação radial de Pittosporum undulatum Vent. (pau-incenso)

    OpenAIRE

    Longui, Eduardo Luiz; Romeiro, Diego; Silva, Morgana Tramontini da; Ribeiro, Ariane; Gouveia, Tatiana Cestini; Lima, Israel Luiz de; Florsheim, Sandra Monteiro Borges

    2011-01-01

    Estudou-se o lenho de Pittosporum undulatum do Parque Estadual Alberto Löfgren, objetivando-se sua caracterização, investigar a variação radial da anatomia e densidade básica, suas correlações e discutir os resultados em um contexto ecológico. Empregaram-se as metodologias usuais para anatomia e densidade da madeira. As características anatômicas corroboram com o descrito para o gênero, ressalta-se a presença de camadas de crescimento, não mencionada na literatura. O diâmetro das fibras não a...

  16. Natural Propagation and Habitat Improvement, Volume I, Oregon, Supplement C, White River Habitat Inventory, 1983 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Heller, David

    1984-04-01

    More than 130 miles of stream fish habitat was inventoried and evaluated on the Mt. Hood National Forest during the first year of this multi-year project. First year tasks included field inventory and evaluation of habitat conditions on the White River and tributary streams thought to have the highest potential for supporting anadromous fish populations. All streams inventoried were located on the Mt. Hood National Forest. The surveyed area appears to contain most of the high quality anadromous fish habitat in the drainage. Habitat conditions appear suitable for steelhead, coho, and chinook salmon, and possibly sockeye. One hundred and twenty-four miles of potential anadromous fish habitat were identifed in the survey. Currently, 32 miles of this habitat would be readily accessible to anadromous fish. An additional 72 miles of habitat could be accessed with only minor passage improvement work. About 20 miles of habitat, however, will require major investment to provide fish passage. Three large lakes (Boulder, 14 acres; Badger, 45 acres; Clear, 550 acres) appear to be well-suited for rearing anadromous fish, although passage enhancement would be needed before self-sustaining runs could be established in any of the lakes.

  17. Proteinas do liquido cefalorraqueano: II. Valores normais das frações proteicas obtidas por eletroforese (variações ligadas a cor, sexo e idade

    Directory of Open Access Journals (Sweden)

    Lucia M. Singer Vermes

    1983-03-01

    Full Text Available Mediante dosagens de proteínas totais e eletroforese sobre acetato de celulose de 213 amostras de LCR normal, obtidas por punção da cisterna magna, foram efetuados estudos para verificação de variações ligadas à cor, sexo e idade. Os resultados obtidos permitiram concluir que: 1. não existem diferenças ligadas à cor no proteinograma do LCR; 2. em crianças, os fatores sexo e idade não influem nos valores estudados; 3. as taxas de proteínas totais e frações protéicas do LCR normal de criança diferem das de homens e de mulheres; 4. em adultos ocorrem variações ligadas ao sexo no proteinograma do LCR; 5. em adultos, proteínas totais e todas frações protéicas, quando expressas em mg/100 ml, aumentam com o avançar da idade. Foram estabelecidas, para a metodologia usada, as taxas fisiológicas do proteinograma do LCR de crianças, homens e mulheres, separadamente.

  18. Anthropogenic areas as incidental substitutes for original habitat.

    Science.gov (United States)

    Martínez-Abraín, Alejandro; Jiménez, Juan

    2016-06-01

    One speaks of ecological substitutes when an introduced species performs, to some extent, the ecosystem function of an extirpated native species. We suggest that a similar case exists for habitats. Species evolve within ecosystems, but habitats can be destroyed or modified by natural and human-made causes. Sometimes habitat alteration forces animals to move to or remain in a suboptimal habitat type. In that case, the habitat is considered a refuge, and the species is called a refugee. Typically refugee species have lower population growth rates than in their original habitats. Human action may lead to the unintended generation of artificial or semiartificial habitat types that functionally resemble the essential features of the original habitat and thus allow a population growth rate of the same magnitude or higher than in the original habitat. We call such areas substitution habitats and define them as human-made habitats within the focal species range that by chance are partial substitutes for the species' original habitat. We call species occupying a substitution habitat adopted species. These are 2 new terms in conservation biology. Examples of substitution habitats are dams for European otters, wheat and rice fields for many steppeland and aquatic birds, and urban areas for storks, falcons, and swifts. Although substitution habitats can bring about increased resilience against the agents of global change, the conservation of original habitat types remains a conservation priority. © 2016 Society for Conservation Biology.

  19. Análise da variação da produtividade dos serviços de água portugueses entre 1994 e 2001 usando a abordagem de malmquist

    Directory of Open Access Journals (Sweden)

    Rui Cunha Marques

    2006-04-01

    Full Text Available A produtividade de uma organização pode ser definida como a relação entre os produtos (outputs e os factores de produção consumidos (inputs. Este artigo discute e aplica uma técnica fronteira de natureza não paramétrica de cálculo da produtividade baseada no índice de produtividade de Malmquist (IPM. Pretende-se, através de um caso prático de aplicação ao sector da água em Portugal, evidenciar as potencialidades dos IPM, que assumem um relevo particular na regulação económica das indústrias de rede. O estudo da produtividade envolve 45 entidades gestoras, abrangendo cerca de 48 % da população portuguesa, e é efectuado para o período 1994-2001. Verifica-se que a evolução da produtividade foi negativa neste período, sobretudo devido à variação da tecnologia de produção e, em menor dimensão, à variação da eficiência de escala. Pelo contrário, a variação da eficiência técnica foi positiva e a variação da eficiência de sobreutilização apresentou um contributo insignificante.A decision-making unit productivity can be defined as the relationship between the products (outputs and the production factors consumed (inputs. This article discusses and applies a non-parametric frontier technique to measure productivity based on the Malmquist productivity index (MPI. By means of a case-study applied to the water sector in Portugal, we intend to stress the MPI strengths which are particularly relevant to the economic regulation of the network industries. The productivity study consists of 45 water services comprising around 48 % of the Portuguese population and it covers the period 1994-2001. We noticed that the productivity change was negative during this period, particularly due to the production technology change and to the scale efficiency change to a less extent. Conversely, the technical efficiency change was positive and the congestion efficiency change presented an insignificant value.

  20. Variações na composição de queijo Minas artesanal da Serra da Canastra nas quatro estações do ano.

    Directory of Open Access Journals (Sweden)

    Luiz Carlos Gonçalves Costa Junior

    2009-12-01

    Full Text Available Muitos, estudos ja foram conduzido com queijos artesanais nas regiões produtoras dc estado de Minas Gerais, e particularmente na Serra da Canastra, porém, os mesmos ainda são muito carentes de estudos que permitam melhoria da qualidade, padronização entre produtores e ao longo das variações sazonais que acontecem. Este trabalho estudou a composição do queijo Canastra a partir da escolha de uma quedaria típica e tradicional da região e em cada uma das quatro estações do ano. Poucas diferenças de temperatura e umidade relativa puderam ser verificadas entre as estações que mostra uma descaracterização entre elas. Porém mesmo assim resultaram em diferenças significativas na composição dos queijos, também per causa da sazonalidade da produção do leite e variação no "pingo", e, ainda pela despadronização do leite para fabricação de queijo, mesmo com o processo de fabricação sendo bem padronizado.

  1. Habitat Suitability Index Models: Yellow-headed blackbird

    Science.gov (United States)

    Schroeder, Richard L.

    1982-01-01

    Habitat preferences of the yellow-headed blackbird (Xanthocephalus xanthocephalus) are described in this publication. It is one of a series of Habitat Suitability Index (HSI) models and was developed through an analysis of available infomration on the species-habitat requirements of the species. Habitat use information is presented in a review of the literature, followed by the development of an HSI model, designed for use in impact assessment and habitat management activities.

  2. Habitat selection and risk of predation: re-colonization by lynx had limited impact on habitat selection by roe deer.

    Directory of Open Access Journals (Sweden)

    Gustaf Samelius

    Full Text Available Risk of predation is an evolutionary force that affects behaviors of virtually all animals. In this study, we examined how habitat selection by roe deer was affected by risk of predation by Eurasian lynx - the main predator of roe deer in Scandinavia. Specifically, we compared how habitat selection by roe deer varied (1 before and after lynx re-established in the study area and (2 in relation to habitat-specific risk of predation by lynx. All analyses were conducted at the spatial and temporal scales of home ranges and seasons. We did not find any evidence that roe deer avoided habitats in which the risk of predation by lynx was greatest and information-theoretic model selection showed that re-colonization by lynx had limited impact on habitat selection by roe deer despite lynx predation causing 65% of known mortalities after lynx re-colonized the area. Instead we found that habitat selection decreased when habitat availability increased for 2 of 5 habitat types (a pattern referred to as functional response in habitat selection. Limited impact of re-colonization by lynx on habitat selection by roe deer in this study differs from elk in North America altering both daily and seasonal patterns in habitat selection at the spatial scales of habitat patches and home ranges when wolves were reintroduced to Yellowstone National Park. Our study thus provides further evidence of the complexity by which animals respond to risk of predation and suggest that it may vary between ecosystems and predator-prey constellations.

  3. Habitat selection and risk of predation: re-colonization by lynx had limited impact on habitat selection by roe deer.

    Science.gov (United States)

    Samelius, Gustaf; Andrén, Henrik; Kjellander, Petter; Liberg, Olof

    2013-01-01

    Risk of predation is an evolutionary force that affects behaviors of virtually all animals. In this study, we examined how habitat selection by roe deer was affected by risk of predation by Eurasian lynx - the main predator of roe deer in Scandinavia. Specifically, we compared how habitat selection by roe deer varied (1) before and after lynx re-established in the study area and (2) in relation to habitat-specific risk of predation by lynx. All analyses were conducted at the spatial and temporal scales of home ranges and seasons. We did not find any evidence that roe deer avoided habitats in which the risk of predation by lynx was greatest and information-theoretic model selection showed that re-colonization by lynx had limited impact on habitat selection by roe deer despite lynx predation causing 65% of known mortalities after lynx re-colonized the area. Instead we found that habitat selection decreased when habitat availability increased for 2 of 5 habitat types (a pattern referred to as functional response in habitat selection). Limited impact of re-colonization by lynx on habitat selection by roe deer in this study differs from elk in North America altering both daily and seasonal patterns in habitat selection at the spatial scales of habitat patches and home ranges when wolves were reintroduced to Yellowstone National Park. Our study thus provides further evidence of the complexity by which animals respond to risk of predation and suggest that it may vary between ecosystems and predator-prey constellations.

  4. Seasonal variation in coastal marine habitat use by the European shag: Insights from fine scale habitat selection modeling and diet

    Science.gov (United States)

    Michelot, Candice; Pinaud, David; Fortin, Matthieu; Maes, Philippe; Callard, Benjamin; Leicher, Marine; Barbraud, Christophe

    2017-07-01

    Studies of habitat selection by higher trophic level species are necessary for using top predator species as indicators of ecosystem functioning. However, contrary to terrestrial ecosystems, few habitat selection studies have been conducted at a fine scale for coastal marine top predator species, and fewer have coupled diet data with habitat selection modeling to highlight a link between prey selection and habitat use. The aim of this study was to characterize spatially and oceanographically, at a fine scale, the habitats used by the European Shag Phalacrocorax aristotelis in the Special Protection Area (SPA) of Houat-Hœdic in the Mor Braz Bay during its foraging activity. Habitat selection models were built using in situ observation data of foraging shags (transect sampling) and spatially explicit environmental data to characterize marine benthic habitats. Observations were first adjusted for detectability biases and shag abundance was subsequently spatialized. The influence of habitat variables on shag abundance was tested using Generalized Linear Models (GLMs). Diet data were finally confronted to habitat selection models. Results showed that European shags breeding in the Mor Braz Bay changed foraging habitats according to the season and to the different environmental and energetic constraints. The proportion of the main preys also varied seasonally. Rocky and coarse sand habitats were clearly preferred compared to fine or muddy sand habitats. Shags appeared to be more selective in their foraging habitats during the breeding period and the rearing of chicks, using essentially rocky areas close to the colony and consuming preferentially fish from the Labridae family and three other fish families in lower proportions. During the post-breeding period shags used a broader range of habitats and mainly consumed Gadidae. Thus, European shags seem to adjust their feeding strategy to minimize energetic costs, to avoid intra-specific competition and to maximize access

  5. Habitat Suitability Index Models: Red-winged blackbird

    Science.gov (United States)

    Short, Henry L.

    1985-01-01

    A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the red-winged blackbird (Agelaius phoeniceus L.). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.

  6. Asotin Creek instream habitat alteration projects : habitat evaluation, adult and juvenile habitat utilization and water temperature monitoring : 2001 progress report

    International Nuclear Information System (INIS)

    Bumgarner, Joseph D.

    2002-01-01

    Asotin Creek originates from a network of deeply incised streams on the slopes of the Blue Mountains of southeastern Washington. The watershed drains an area of 322 square miles that provides a mean annual flow of 74 cfs. The geomorphology of the watershed exerts a strong influence on biologic conditions for fish within the stream. Historic and contemporary land-use practices have had a profound impact on the kind, abundance, and distribution of anadromous salmonids in the watershed. Fish habitat in Asotin Creek and other local streams has been affected by agricultural development, grazing, tilling practices, logging, recreational activities and implementation of flood control structures (Neilson 1950). The Asotin Creek Model Watershed Master Plan was completed in 1994. The plan was developed by a landowner steering committee for the Asotin County Conservation District (ACCD), with technical support from various Federal, State and local entities. Actions identified within the plan to improve the Asotin Creek ecosystem fall into four main categories: (1) Stream and Riparian, (2) Forestland, (3) Rangeland, and (4) Cropland. Specific actions to be carried out within the stream and in the riparian area to improve fish habitat were: (1) create more pools, (2) increase the amount of large organic debris (LOD), (3) increase the riparian buffer zone through tree planting, and (4) increase fencing to limit livestock access. All of these actions, in combination with other activities identified in the Plan, are intended to stabilize the river channel, reduce sediment input, increase the amount of available fish habitat (adult and juvenile) and protect private property. Evaluation work described within this report was to document the success or failure of the program regarding the first two items listed (increasing pools and LOD). Beginning in 1996, the ACCD, with cooperation from local landowners and funding from Bonneville Power Administration began constructing instream

  7. Testing projected wild bee distributions in agricultural habitats: predictive power depends on species traits and habitat type.

    Science.gov (United States)

    Marshall, Leon; Carvalheiro, Luísa G; Aguirre-Gutiérrez, Jesús; Bos, Merijn; de Groot, G Arjen; Kleijn, David; Potts, Simon G; Reemer, Menno; Roberts, Stuart; Scheper, Jeroen; Biesmeijer, Jacobus C

    2015-10-01

    Species distribution models (SDM) are increasingly used to understand the factors that regulate variation in biodiversity patterns and to help plan conservation strategies. However, these models are rarely validated with independently collected data and it is unclear whether SDM performance is maintained across distinct habitats and for species with different functional traits. Highly mobile species, such as bees, can be particularly challenging to model. Here, we use independent sets of occurrence data collected systematically in several agricultural habitats to test how the predictive performance of SDMs for wild bee species depends on species traits, habitat type, and sampling technique. We used a species distribution modeling approach parametrized for the Netherlands, with presence records from 1990 to 2010 for 193 Dutch wild bees. For each species, we built a Maxent model based on 13 climate and landscape variables. We tested the predictive performance of the SDMs with independent datasets collected from orchards and arable fields across the Netherlands from 2010 to 2013, using transect surveys or pan traps. Model predictive performance depended on species traits and habitat type. Occurrence of bee species specialized in habitat and diet was better predicted than generalist bees. Predictions of habitat suitability were also more precise for habitats that are temporally more stable (orchards) than for habitats that suffer regular alterations (arable), particularly for small, solitary bees. As a conservation tool, SDMs are best suited to modeling rarer, specialist species than more generalist and will work best in long-term stable habitats. The variability of complex, short-term habitats is difficult to capture in such models and historical land use generally has low thematic resolution. To improve SDMs' usefulness, models require explanatory variables and collection data that include detailed landscape characteristics, for example, variability of crops and

  8. Moving Targets and Biodiversity Offsets for Endangered Species Habitat: Is Lesser Prairie Chicken Habitat a Stock or Flow?

    Directory of Open Access Journals (Sweden)

    Todd K. BenDor

    2014-03-01

    Full Text Available The US Fish and Wildlife Service will make an Endangered Species Act listing decision for the lesser prairie chicken (Tympanuchus pallidicinctus; “LPC” in March 2014. Based on the findings of a single, Uzbek antelope study, conservation plans put forth for the LPC propose to modify and re-position habitat in the landscape through a series of temporary preservation/restoration efforts. We argue that for certain species, including the LPC, dynamic habitat offsets represent a dangerous re-interpretation of habitat provision and recovery programs, which have nearly-universally viewed ecosystem offsets (habitat, wetlands, streams, etc. as “stocks” that accumulate characteristics over time. Any effort to create a program of temporary, moving habitat offsets must consider species’ (1 life history characteristics, (2 behavioral tendencies (e.g., avoidance of impacted areas, nesting/breeding site fidelity, and (3 habitat restoration characteristics, including long temporal lags in reoccupation. If misapplied, species recovery programs using temporary, moving habitat risk further population declines.

  9. A meta-analysis of lesser prairie-chicken nesting and brood-rearing habitats: implications for habitat management

    Science.gov (United States)

    Hagen, Christian A.; Grisham, Blake A.; Boal, Clint W.; Haukos, David A.

    2013-01-01

    The distribution and range of lesser prairie-chicken (Tympanuchus pallidicinctus) has been reduced by >90% since European settlement of the Great Plains of North America. Currently, lesser prairie-chickens occupy 3 general vegetation communities: sand sagebrush (Artemisia filifolia), sand shinnery oak (Quercus havardii), and mixed-grass prairies juxtaposed with Conservation Reserve Program grasslands. As a candidate for protection under the Endangered Species Act, there is a need for a synthesis that characterizes habitat structure rangewide. Thus, we conducted a meta-analysis of vegetation characteristics at nest sites and brood habitats to determine whether there was an overall effect (Hedges' d) of habitat selection and to estimate average (95% CI) habitat characteristics at use sites. We estimated effect sizes (di) from the difference between use (nests and brood sites) and random sampling sites for each study (n = 14), and derived an overall effect size (d++). There was a general effect for habitat selection as evidenced by low levels of variation in effect sizes across studies and regions. There was a small to medium effect (d++) = 0.20-0.82) of selection for greater vertical structure (visual obstruction) by nesting females in both vegetation communities, and selection against bare ground (d++ = 0.20-0.58). Females with broods exhibited less selectivity for habitat components except for vertical structure. The variation of d++ was greater during nesting than brooding periods, signifying a seasonal shift in habitat use, and perhaps a greater range of tolerance for brood-rearing habitat. The overall estimates of vegetation cover were consistent with those provided in management guidelines for the species.

  10. Geografia da mortalidade infantil do Brasil: variações espaciais e desigualdades territoriais

    Directory of Open Access Journals (Sweden)

    Rivaldo Faria

    2016-12-01

    Full Text Available O objetivo deste artigo é analisar as variações espaciais e as desigualdades territoriais nos indicadores de mortalidade infantil do Brasil. O estudo foi feito com todos os óbitos infantis e nascidos vivos registrados em sistemas oficiais nos anos de 2012 e 2013 nas 558 microrregiões brasileiras. Os indicadores foram calculados e estimados através do método bayesiano empírico. As características do território foram analisadas através de um indicador multicritério denominado Índice de Privação Social. Os resultados indicaram elevados coeficientes de mortalidade infantil (CMI nas microrregiões dos estados do nordeste e norte do país e fatores associados relacionados à idade da mãe, doenças infecciosas, vazios assistenciais e falta de acompanhamento pré-natal. Nas microrregiões dos estados do sudeste e sul e parte do centro-oeste os CMI são menos elevados e os fatores associados estão mais relacionados com a prematuridade e baixo peso à nascença.

  11. Wildlife Habitat Evaluation Handbook.

    Science.gov (United States)

    Neilson, Edward L., Jr.; Benson, Delwin E.

    The National 4-H Wildlife Invitational is a competitive event to teach youth about the fundamentals of wildlife management. Youth learn that management for wildlife means management of wildlife habitat and providing for the needs of wildlife. This handbook provides information about wildlife habitat management concepts in both urban and rural…

  12. Effects of Changes in Lugu Lake Water Quality on Schizothorax Yunnansis Ecological Habitat Based on HABITAT Model

    Science.gov (United States)

    Huang, Wei; Mynnet, Arthur

    Schizothorax Yunnansis is an unique fish species only existing in Lugu Lake, which is located in the southwestern China. The simulation and research on Schizothorax Yunnansis habitat environment have a vital significance to protect this rare fish. With the development of the tourism industry, there bring more pressure on the environmental protection. The living environment of Schizothorax Yunnansis is destroyed seriously because the water quality is suffering the sustaining pollution of domestic sewage from the peripheral villages. This paper analyzes the relationship between water quality change and Schizothorax Yunnansis ecological habitat and evalutes Schizothorax Yunnansis's ecological habitat impact based on HABITAT model. The results show that when the TP concentration in Lugu Lake does not exceed Schizothorax Yunnansis's survival threshold, Schizothorax Yunnansis can get more nutrients and the suitable habitat area for itself is increased. Conversely, it can lead to TP toxicity in the Schizothorax Yunnansis and even death. Therefore, unsuitable habitat area for Schizothorax Yunnansis is increased. It can be seen from the results that HABITAT model can assist in ecological impact assessment studies by translating results of hydrological, water quality models into effects on the natural environment and human society.

  13. Fast Identification of Radical Scavengers from Securigera varia by Combining 13C-NMR-Based Dereplication to Bioactivity-Guided Fractionation.

    Science.gov (United States)

    Sientzoff, Pacôme; Hubert, Jane; Janin, Coralie; Voutquenne-Nazabadioko, Laurence; Renault, Jean-Hugues; Nuzillard, Jean-Marc; Harakat, Dominique; Magid, Abdulmagid Alabdul

    2015-08-14

    Securigera varia (Fabaceae) is a common herbaceous perennial plant widely growing in Europe and Asia and purposely established for erosion control, roadside planting, and soil rehabilitation. The aim of this study was to determine the radical scavenging activity of a crude methanol extract of S. varia aerial parts by using the free radical DPPH (1,1-diphenyl-2-picrylhydrazyl) and to rapidly identify the compounds involved in this activity. The crude extract was initially separated in five fractions on Diaion HP20 resin and the most active part was fractionated by Centrifugal Partition Extraction (CPE). Known compounds were directly identified by a (13)C-NMR-based dereplication method. Semi-preparative high performance liquid chromatography purification experiments were further performed to identify unknown or minor active compounds. As a result, one new (13) and twelve known flavonoid glycosides together with three nitropropanoylglucopyranoses were isolated, including astragalin (1), kaempferol-3-O-(6-O-acetyl)-β-D-glucopyranoside (2), kaempferol-3,4'-di-O-β-D-glucopyranoside (3), trifolin (4), isoquercitrin (5), hyperoside (6), isovitexin (7), isoorientin (8), isovitexin 4'-O-β-D-glucopyranoside (9), apigenin 7-O-β-D-glucuronopyranoside (10), luteolin 7-O-β-D-glucuronopyranoside (11), apigenin 7-O-α-L-rhamnopyranosyl-(1→2)-β-D-glucuronopyranoside (12), apigenin 7-O-β-D-glucopyranosyl-(1 → 2)-β-D-glucuronopyranoside (13), 6-O-(3-nitropropanoyl)-β-D-glucopyranoside (14), coronillin (16) and coronarian (15). 120 mg of the most active compound isoorientin against the free radical DPPH was recovered by CPE with an HPLC purity of 99%.

  14. Fast Identification of Radical Scavengers from Securigera varia by Combining 13C-NMR-Based Dereplication to Bioactivity-Guided Fractionation

    Directory of Open Access Journals (Sweden)

    Pacôme Sientzoff

    2015-08-01

    Full Text Available Securigera varia (Fabaceae is a common herbaceous perennial plant widely growing in Europe and Asia and purposely established for erosion control, roadside planting, and soil rehabilitation. The aim of this study was to determine the radical scavenging activity of a crude methanol extract of S. varia aerial parts by using the free radical DPPH (1,1-diphenyl-2-picrylhydrazyl and to rapidly identify the compounds involved in this activity. The crude extract was initially separated in five fractions on Diaion HP20 resin and the most active part was fractionated by Centrifugal Partition Extraction (CPE. Known compounds were directly identified by a 13C-NMR-based dereplication method. Semi-preparative high performance liquid chromatography purification experiments were further performed to identify unknown or minor active compounds. As a result, one new (13 and twelve known flavonoid glycosides together with three nitropropanoylglucopyranoses were isolated, including astragalin (1, kaempferol-3-O-(6-O-acetyl-β-D-glucopyranoside (2, kaempferol-3,4′-di-O-β-D-glucopyranoside (3, trifolin (4, isoquercitrin (5, hyperoside (6, isovitexin (7, isoorientin (8, isovitexin 4′-O-β-D-glucopyranoside (9, apigenin 7-O-β-D-glucuronopyranoside (10, luteolin 7-O-β-D-glucuronopyranoside (11, apigenin 7-O-α-L-rhamnopyranosyl-(1→2-β-D-glucuronopyranoside (12, apigenin 7-O-β-D-glucopyranosyl-(1→2-β-D-glucuronopyranoside (13, 6-O-(3-nitropropanoyl-β-D-glucopyranoside (14, coronillin (16 and coronarian (15. 120 mg of the most active compound isoorientin against the free radical DPPH was recovered by CPE with an HPLC purity of 99%.

  15. Variação e contatos linguísticos do vestfaliano rio-grandense falado no Vale do Taquari

    OpenAIRE

    Aline Horst

    2014-01-01

    A presente Dissertação apresenta as etapas e os resultados de uma pesquisa que objetiva descrever os processos envolvidos na variação e constituição da língua brasileira de imigração alemã vestfaliano (We, também conhecida como sapato-de-pau, Plattdüütsch), identificando aspectos de sua configuração linguística e as territorialidades de uso e manutenção dessa língua em um contexto de plurilinguismo e de contato com variedades do português (Pt) e do alemão (Dt - Deutsch), sobretudo do Hunsrück...

  16. Habitat segregation in fish assemblages

    OpenAIRE

    Ibbotson, A.T.

    1990-01-01

    The segregation of habitats of fish assemblages found in the chalk streams and rivers within the Wessex, South West and Southern Water Authority boundaries in southern England have been examined. Habitat segregation is the most frequent type of resource partitioning in natural communities. The habitat of individual fish species will be defined in order to determine the following: (1) the requirements of each species in terms of depth, current velocity, substrate, cover etc.; (2) identify the ...

  17. Critical Habitat :: NOAA Fisheries

    Science.gov (United States)

    occupied by the species at the time of listing, if they contain physical or biological features essential essential for conservation. Critical Habitat Maps NOTE: The critical habitat maps provided here are for Data Leatherback Turtle (U.S. West Coast) » Biological Report » Economic Report 2012 77 FR 4170 Go to

  18. Riparian Habitat - Product of 2 riparian habitat workshops

    Data.gov (United States)

    California Natural Resource Agency — In two riparian habitat workshops held between 2001 and 2002, scientists and managers identified the need for determining the scope of a consistent and acceptable...

  19. Habitat stability, predation risk and 'memory syndromes'.

    Science.gov (United States)

    Dalesman, S; Rendle, A; Dall, S R X

    2015-05-27

    Habitat stability and predation pressure are thought to be major drivers in the evolutionary maintenance of behavioural syndromes, with trait covariance only occurring within specific habitats. However, animals also exhibit behavioural plasticity, often through memory formation. Memory formation across traits may be linked, with covariance in memory traits (memory syndromes) selected under particular environmental conditions. This study tests whether the pond snail, Lymnaea stagnalis, demonstrates consistency among memory traits ('memory syndrome') related to threat avoidance and foraging. We used eight populations originating from three different habitat types: i) laboratory populations (stable habitat, predator-free); ii) river populations (fairly stable habitat, fish predation); and iii) ditch populations (unstable habitat, invertebrate predation). At a population level, there was a negative relationship between memories related to threat avoidance and food selectivity, but no consistency within habitat type. At an individual level, covariance between memory traits was dependent on habitat. Laboratory populations showed no covariance among memory traits, whereas river populations showed a positive correlation between food memories, and ditch populations demonstrated a negative relationship between threat memory and food memories. Therefore, selection pressures among habitats appear to act independently on memory trait covariation at an individual level and the average response within a population.

  20. NEPR Benthic Habitat Map 2015

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This benthic habitat map was created from a semi-automated habitat mapping process, using a combination of bathymetry, satellite imagery, aerial imagery and...

  1. Deep Space Habitat Concept Demonstrator

    Science.gov (United States)

    Bookout, Paul S.; Smitherman, David

    2015-01-01

    This project will develop, integrate, test, and evaluate Habitation Systems that will be utilized as technology testbeds and will advance NASA's understanding of alternative deep space mission architectures, requirements, and operations concepts. Rapid prototyping and existing hardware will be utilized to develop full-scale habitat demonstrators. FY 2014 focused on the development of a large volume Space Launch System (SLS) class habitat (Skylab Gen 2) based on the SLS hydrogen tank components. Similar to the original Skylab, a tank section of the SLS rocket can be outfitted with a deep space habitat configuration and launched as a payload on an SLS rocket. This concept can be used to support extended stay at the Lunar Distant Retrograde Orbit to support the Asteroid Retrieval Mission and provide a habitat suitable for human missions to Mars.

  2. Salmon River Habitat Enhancement, 1984 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Konopacky, Richard C.

    1986-04-01

    This report has four volumes: a Tribal project annual report (Part 1) and three reports (Parts 2, 3, and 4) prepared for the Tribes by their engineering subcontractor. The Tribal project annual report contains reports for four subprojects within Project 83-359. Subproject I involved habitat and fish inventories in Bear Valley Creek, Valley County, Idaho that will be used to evaluate responses to ongoing habitat enhancement. Subproject II is the coordination/planning activities of the Project Leader in relation to other BPA-funded habitat enhancement projects that have or will occur within the traditional Treaty (Fort Bridger Treaty of 1868) fishing areas of the Shoshone-Bannock Tribes, Fort Hall Reservation, Idaho. Subproject III involved habitat and fish inventories (pretreatment) and habitat problem identification on the Yankee Fork of the Salmon River (including Jordan Creek). Subproject IV during 1985 involved habitat problem identification in the East Fork of the Salmon River and habitat and fish inventories (pretreatment) in Herd Creek, a tributary to the East Fork.

  3. Loss and modification of habitat

    Science.gov (United States)

    Lemckert, Francis; Hecnar, Stephen; Pilliod, David S.; Wilkinson, John W.; Heatwole, Harold

    2012-01-01

    Amphibians live in a wide variety of habitats around the world, many of which have been modified or destroyed by human activities. Most species have unique life history characteristics adapted to specific climates, habitats (e.g., lentic, lotic, terrestrial, arboreal, fossorial, amphibious), and local conditions that provide suitable areas for reproduction, development and growth, shelter from environmental extremes, and predation, as well as connectivity to other populations or habitats. Although some species are entirely aquatic or terrestrial, most amphibians, as their name implies, lead a dual life and require a mosaic of habitats in both aquatic and terrestrial ecosystems. With over 6 billion people on Earth, most species are now persisting in habitats that have been directly or indirectly influenced by human activities. Some species have disappeared where their habitats have been completely destroyed, reduced, or rendered unsuitable. Habitat loss and degradation are widely considered by most researchers as the most important causes of amphibian population decline globally (Barinaga 1990; Wake and Morowitz 1991; Alford and Richards 1999). In this chapter, a background on the diverse habitat requirements of amphibians is provided, followed by a discussion of the effects of urbanization, agriculture, livestock grazing, timber production and harvesting, fire and hazardous fuel management, and roads on amphibians and their habitats. Also briefly discussed is the influence on amphibian habitats of natural disturbances, such as extreme weather events and climate change, given the potential for human activities to impact climate in the longer term. For amphibians in general, microhabitats are of greater importance than for other vertebrates. As ectotherms with a skin that is permeable to water and with naked gelatinous eggs, amphibians are physiologically constrained to be active during environmental conditions that provide appropriate body temperatures and adequate

  4. NORTHWOODS Wildlife Habitat Data Base

    Science.gov (United States)

    Mark D. Nelson; Janine M. Benyus; Richard R. Buech

    1992-01-01

    Wildlife habitat data from seven Great Lakes National Forests were combined into a wildlife-habitat matrix named NORTHWOODS. Several electronic file formats of NORTHWOODS data base and documentation are available on floppy disks for microcomputers.

  5. 50 CFR 17.94 - Critical habitats.

    Science.gov (United States)

    2010-10-01

    ... habitats. (a) The areas listed in § 17.95 (fish and wildlife) and § 17.96 (plants) and referred to in the... physical constituent elements within the defined area of Critical Habitat that are essential to the... 50 Wildlife and Fisheries 2 2010-10-01 2010-10-01 false Critical habitats. 17.94 Section 17.94...

  6. Habitat selection by owls in a seasonal semi-deciduous forest in southern Brazil

    Directory of Open Access Journals (Sweden)

    W. Menq

    Full Text Available Abstract This paper tested the hypothesis that the structural components of vegetation have impact over the distribution of owl species in a fragment of a semi-deciduous seasonal forest. This paper also determined which vegetation variables contributed to the spatial distribution of owl species. It was developed in the Perobas Biological Reserve (PBR between September and December 2011. To conduct the owl census, a playback technique was applied at hearing points distributed to cover different vegetation types in the study area. A total of 56 individual owls of six species were recorded: Tropical Screech-Owl (Megascops choliba, Black-capped Screech-Owl (Megascops atricapilla, Tawny-browed Owl (Pulsatrix koeniswaldiana, Ferruginous Pygmy-Owl (Glaucidium brasilianum, Mottled Owl (Strix virgata and Stygian Owl (Asio stygius. The results suggest that the variables of vegetation structure have impact on the occurrence of owls. The canopy height, the presence of hollow trees, fallen trees and glades are the most important structural components influencing owl distribution in the sampled area.

  7. The areal extent of brown shrimp habitat suitability in Mobile Bay, Alabama, USA: Targeting vegetated habitat restoration

    Science.gov (United States)

    Smith, L.M.; Nestlerode, J.A.; Harwell, L.C.; Bourgeois, P.

    2010-01-01

    The availability of wetlands and shallow water habitats significantly influences Gulf of Mexico (GOM) penaeid shrimp fishery productivity. However, the GOM region has the highest rate of wetland loss in the USA. Protection and management of these vital GOM habitats are critical to sustainable shrimp fisheries. Brown shrimp (Farfantepenaeus aztecus) are a major component of GOM fisheries. We present an approach for estimating the areal extent of suitable habitat for post-larval and juvenile brown shrimp in Mobile Bay, Alabama, using an existing habitat suitability index model for the northern GOM calculated from probabilistic survey of water quality and sediment data, land cover data, and submerged aquatic vegetation coverages. This estuarine scale approach is intended to support targeted protection and restoration of these habitats. These analyses indicate that approximately 60% of the area of Mobile Bay is categorized as suitable to near optimal for post-larval and juvenile shrimp and 38% of the area is marginally to minimally suitable. We identify potential units within Mobile Bay for targeted restoration to improve habitat suitability. ?? 2010 Springer Science+Business Media B.V.

  8. Fuzzy modelling of Atlantic salmon physical habitat

    Science.gov (United States)

    St-Hilaire, André; Mocq, Julien; Cunjak, Richard

    2015-04-01

    Fish habitat models typically attempt to quantify the amount of available river habitat for a given fish species for various flow and hydraulic conditions. To achieve this, information on the preferred range of values of key physical habitat variables (e.g. water level, velocity, substrate diameter) for the targeted fishs pecies need to be modelled. In this context, we developed several habitat suitability indices sets for three Atlantic salmon life stages (young-of-the-year (YOY), parr, spawning adults) with the help of fuzzy logic modeling. Using the knowledge of twenty-seven experts, from both sides of the Atlantic Ocean, we defined fuzzy sets of four variables (depth, substrate size, velocity and Habitat Suitability Index, or HSI) and associated fuzzy rules. When applied to the Romaine River (Canada), median curves of standardized Weighted Usable Area (WUA) were calculated and a confidence interval was obtained by bootstrap resampling. Despite the large range of WUA covered by the expert WUA curves, confidence intervals were relatively narrow: an average width of 0.095 (on a scale of 0 to 1) for spawning habitat, 0.155 for parr rearing habitat and 0.160 for YOY rearing habitat. When considering an environmental flow value corresponding to 90% of the maximum reached by WUA curve, results seem acceptable for the Romaine River. Generally, this proposed fuzzy logic method seems suitable to model habitat availability for the three life stages, while also providing an estimate of uncertainty in salmon preferences.

  9. Does learning or instinct shape habitat selection?

    Directory of Open Access Journals (Sweden)

    Scott E Nielsen

    Full Text Available Habitat selection is an important behavioural process widely studied for its population-level effects. Models of habitat selection are, however, often fit without a mechanistic consideration. Here, we investigated whether patterns in habitat selection result from instinct or learning for a population of grizzly bears (Ursus arctos in Alberta, Canada. We found that habitat selection and relatedness were positively correlated in female bears during the fall season, with a trend in the spring, but not during any season for males. This suggests that habitat selection is a learned behaviour because males do not participate in parental care: a genetically predetermined behaviour (instinct would have resulted in habitat selection and relatedness correlations for both sexes. Geographic distance and home range overlap among animals did not alter correlations indicating that dispersal and spatial autocorrelation had little effect on the observed trends. These results suggest that habitat selection in grizzly bears are partly learned from their mothers, which could have implications for the translocation of wildlife to novel environments.

  10. Habitat preference of Roan Antelope (Hippotragus equinus ...

    African Journals Online (AJOL)

    Key words: Habitat Preference, Roan Antelope, Seasons. INTRODUCTION. Habitat quality and quantity have been identified as the primary limiting factors that influence animal population dynamics. (Jansen et al., 2001). Habitat influences the presence, abundance, distribution, movement and behavior of game animals.

  11. Habitat-specific population growth of a farmland bird.

    Directory of Open Access Journals (Sweden)

    Debora Arlt

    Full Text Available BACKGROUND: To assess population persistence of species living in heterogeneous landscapes, the effects of habitat on reproduction and survival have to be investigated. METHODOLOGY/PRINCIPAL FINDINGS: We used a matrix population model to estimate habitat-specific population growth rates for a population of northern wheatears Oenanthe oenanthe breeding in farmland consisting of a mosaic of distinct habitat (land use types. Based on extensive long-term data on reproduction and survival, habitats characterised by tall field layers (spring- and autumn-sown crop fields, ungrazed grasslands displayed negative stochastic population growth rates (log lambda(s: -0.332, -0.429, -0.168, respectively, that were markedly lower than growth rates of habitats characterised by permanently short field layers (pastures grazed by cattle or horses, and farmyards, log lambda(s: -0.056, +0.081, -0.059. Although habitats differed with respect to reproductive performance, differences in habitat-specific population growth were largely due to differences in adult and first-year survival rates, as shown by a life table response experiment (LTRE. CONCLUSIONS/SIGNIFICANCE: Our results show that estimation of survival rates is important for realistic assessments of habitat quality. Results also indicate that grazed grasslands and farmyards may act as source habitats, whereas crop fields and ungrazed grasslands with tall field layers may act as sink habitats. We suggest that the strong decline of northern wheatears in Swedish farmland may be linked to the corresponding observed loss of high quality breeding habitat, i.e. grazed semi-natural grasslands.

  12. Variação do incremento anual ao longo do fuste de Pinus taeda L. em diferentes idades e densidades populacionais.

    Directory of Open Access Journals (Sweden)

    César Martins Andrade

    2010-08-01

    Full Text Available A variação do crescimento anual em diferentes alturas do fuste de Pinus taeda L. foi estudada por meio da análise de tronco em árvores do estrato dominante e médio. Foram coletadas secções transversais ao longo do fuste de 9 árvores-amostra, tomadas na base, à altura do peito (DAP, e após, a cada metro. A amostragem foi constituída de 4 árvores provenientes de Canela, Rio Grande do Sul, em floresta com 17 anos de idade, submetida a um desbaste, e 5 árvores de Ponte Alta do Norte, Santa Catarina, em floresta com 34 anos, submetida a cinco desbastes. Os resultados, expressos na forma percentual do incremento em área basal na posição "i", sobre o incremento em área basal ao nível do DAP, mostraram a forte variação na deposição anual de lenho ao longo do fuste em função da densidade populacional, caracterizando os efeitos da competição e da liberação pela execução do desbaste. Árvores sujeitas à competição mostraram maior crescimento nas partes superiores do fuste, enquanto que árvores sob menor concorrência apresentaram maior crescimento em posições inferiores, facilmente identificadas pela forma e inclinação das curvas de incremento.

  13. Teaching animal habitat selection using wildlife tracking equipment

    Science.gov (United States)

    Laskowski, Jessica; Gillespie, Caitlyn R.; Corral, Lucia; Oden, Amy; Fricke, Kent A.; Fontaine, Joseph J.

    2016-01-01

    We present a hands-on outdoor activity coupled with classroom discussion to teach students about wildlife habitat selection, the process by which animals choose where to live. By selecting locations or habitats with many benefits (e.g., food, shelter, mates) and few costs (e.g., predators), animals improve their ability to survive and reproduce. Biologists track animal movement using radio telemetry technology to study habitat selection so they can better provide species with habitats that promote population growth. We present a curriculum in which students locate “animals” (transmitters) using radio telemetry equipment and apply math skills (use of fractions and percentages) to assess their “animal's” habitat selection by comparing the availability of habitat types with the proportion of “animals” they find in each habitat type.

  14. Creating complex habitats for restoration and reconciliation

    NARCIS (Netherlands)

    Loke, L.H.L.; Ladle, R.J.; Bouma, T.J.; Todd, P.A.

    2015-01-01

    Simplification of natural habitats has become a major conservation challenge and there is a growing consensus that incorporating and enhancing habitat complexity is likely to be critical for future restoration efforts. Habitat complexity is often ascribed an important role in controlling species

  15. Habitat specialization through germination cueing

    DEFF Research Database (Denmark)

    Ten Brink, Dirk-Jan; Hendriksma, Harmen; Bruun, Hans Henrik

    2013-01-01

    This study examined the adaptive association between seed germination ecology and specialization to either forest or open habitats across a range of evolutionary lineages of seed plants, in order to test the hypotheses that (1) species' specialization to open vs. shaded habitats is consistently...

  16. Habitat Use and Selection by Giant Pandas

    Science.gov (United States)

    Hull, Vanessa; Zhang, Jindong; Huang, Jinyan; Zhou, Shiqiang; Viña, Andrés; Shortridge, Ashton; Li, Rengui; Liu, Dian; Xu, Weihua; Ouyang, Zhiyun; Zhang, Hemin; Liu, Jianguo

    2016-01-01

    Animals make choices about where to spend their time in complex and dynamic landscapes, choices that reveal information about their biology that in turn can be used to guide their conservation. Using GPS collars, we conducted a novel individual-based analysis of habitat use and selection by the elusive and endangered giant pandas (Ailuropoda melanoleuca). We constructed spatial autoregressive resource utilization functions (RUF) to model the relationship between the pandas' utilization distributions and various habitat characteristics over a continuous space across seasons. Results reveal several new insights, including use of a broader range of habitat characteristics than previously understood for the species, particularly steep slopes and non-forest areas. We also used compositional analysis to analyze habitat selection (use with respect to availability of habitat types) at two selection levels. Pandas selected against low terrain position and against the highest clumped forest at the at-home range level, but no significant factors were identified at the within-home range level. Our results have implications for modeling and managing the habitat of this endangered species by illustrating how individual pandas relate to habitat and make choices that differ from assumptions made in broad scale models. Our study also highlights the value of using a spatial autoregressive RUF approach on animal species for which a complete picture of individual-level habitat use and selection across space is otherwise lacking. PMID:27627805

  17. Habitat Use and Selection by Giant Pandas.

    Directory of Open Access Journals (Sweden)

    Vanessa Hull

    Full Text Available Animals make choices about where to spend their time in complex and dynamic landscapes, choices that reveal information about their biology that in turn can be used to guide their conservation. Using GPS collars, we conducted a novel individual-based analysis of habitat use and selection by the elusive and endangered giant pandas (Ailuropoda melanoleuca. We constructed spatial autoregressive resource utilization functions (RUF to model the relationship between the pandas' utilization distributions and various habitat characteristics over a continuous space across seasons. Results reveal several new insights, including use of a broader range of habitat characteristics than previously understood for the species, particularly steep slopes and non-forest areas. We also used compositional analysis to analyze habitat selection (use with respect to availability of habitat types at two selection levels. Pandas selected against low terrain position and against the highest clumped forest at the at-home range level, but no significant factors were identified at the within-home range level. Our results have implications for modeling and managing the habitat of this endangered species by illustrating how individual pandas relate to habitat and make choices that differ from assumptions made in broad scale models. Our study also highlights the value of using a spatial autoregressive RUF approach on animal species for which a complete picture of individual-level habitat use and selection across space is otherwise lacking.

  18. Pelagic habitat visualization: the need for a third (and fourth) dimension: HabitatSpace

    Science.gov (United States)

    Beegle-Krause, C; Vance, Tiffany; Reusser, Debbie; Stuebe, David; Howlett, Eoin

    2009-01-01

    Habitat in open water is not simply a 2-D to 2.5-D surface such as the ocean bottom or the air-water interface. Rather, pelagic habitat is a 3-D volume of water that can change over time, leading us to the term habitat space. Visualization and analysis in 2-D is well supported with GIS tools, but a new tool was needed for visualization and analysis in four dimensions. Observational data (cruise profiles (xo, yo, z, to)), numerical circulation model fields (x,y,z,t), and trajectories (larval fish, 4-D line) need to be merged together in a meaningful way for visualization and analysis. As a first step toward this new framework, UNIDATA’s Integrated Data Viewer (IDV) has been used to create a set of tools for habitat analysis in 4-D. IDV was designed for 3-D+time geospatial data in the meteorological community. NetCDF JavaTM libraries allow the tool to read many file formats including remotely located data (e.g. data available via OPeNDAP ). With this project, IDV has been adapted for use in delineating habitat space for multiple fish species in the ocean. The ability to define and visualize boundaries of a water mass, which meets specific biologically relevant criteria (e.g., volume, connectedness, and inter-annual variability) based on model results and observational data, will allow managers to investigate the survival of individual year classes of commercially important fisheries. Better understanding of the survival of these year classes will lead to improved forecasting of fisheries recruitment.

  19. Varying energetic costs of Brent Geese along a continuum from aquatic to agricultural habitats: the importance of habitat-specific energy expenditure

    DEFF Research Database (Denmark)

    Clausen, Kevin Kuhlmann; Clausen, Preben; Fox, Anthony David

    2013-01-01

    and alert than birds feeding in aquatic areas, and also spent much less time roosting. Frequency of disturbance was found to be higher in terrestrial habitats compared to aquatic habitats. These stress-related behavioural differences between habitats highlight the vulnerability of the species associated...... with adapting to different food sources. Combining time-budgets with activity-specific BMR-multiplicators showed that activity-based metabolic rates ranged from 1.7 to 2.7 × BMR within habitats exploited by Brent Geese, and emphasized that aquatic areas represent the energetically least expensive foraging...... habitat for these birds. This is largely the result of habitat-specific variation in time spent flying. These findings underline the importance of measuring habitat-specific behaviour and disturbance when studying avian energetics, and demonstrate the risk of uncritically using allometric relationships...

  20. Data Collection and Simulation of Ecological Habitat and Recreational Habitat in the Shenandoah River, Virginia

    Science.gov (United States)

    Krstolic, Jennifer L.

    2015-01-01

    This report presents updates to methods, describes additional data collected, documents modeling results, and discusses implications from an updated habitat-flow model that can be used to predict ecological habitat for fish and recreational habitat for canoeing on the main stem Shenandoah River in Virginia. Given a 76-percent increase in population predictions for 2040 over 1995 records, increased water-withdrawal scenarios were evaluated to determine the effects on habitat and recreation in the Shenandoah River. Projected water demands for 2040 vary by watershed: the North Fork Shenandoah River shows a 55.9-percent increase, the South Fork Shenandoah River shows a 46.5-percent increase, and the main stem Shenandoah River shows a 52-percent increase; most localities are projected to approach the total permitted surface-water and groundwater withdrawals values by 2040, and a few localities are projected to exceed these values.

  1. Assessing habitat selection when availability changes

    Science.gov (United States)

    Arthur, S.; Garner, G.; ,

    1996-01-01

    We present a method of comparing data on habitat use and availability that allows availability to differ among observations. This method is applicable when habitats change over time and when animals are unable to move throughout a predetermined study area between observations. We used maximum-likelihood techniques to derive an index that estimates the probability that each habitat type would be used if all were equally available. We also demonstrate how these indices can be used to compare relative use of available habitats, assign them ranks, and assess statistical differences between pairs of indices. The set of these indices for all habitats can be compared between groups of animals that represent different seasons, sex or age classes, or experimental treatments. This method allows quantitative comparisons among types and is not affected by arbitrary decisions about which habitats to include in the study. We provide an example by comparing the availability of four categories of sea ice concentration to their use by adult female polar bears, whose movements were monitored by satellite radio tracking in the Bering and Chukchi Seas during 1990. Use of ice categories by bears was nonrandom, and the pattern of use differed between spring and late summer seasons.

  2. Habitat features and predictive habitat modeling for the Colorado chipmunk in southern New Mexico

    Science.gov (United States)

    Rivieccio, M.; Thompson, B.C.; Gould, W.R.; Boykin, K.G.

    2003-01-01

    Two subspecies of Colorado chipmunk (state threatened and federal species of concern) occur in southern New Mexico: Tamias quadrivittatus australis in the Organ Mountains and T. q. oscuraensis in the Oscura Mountains. We developed a GIS model of potentially suitable habitat based on vegetation and elevation features, evaluated site classifications of the GIS model, and determined vegetation and terrain features associated with chipmunk occurrence. We compared GIS model classifications with actual vegetation and elevation features measured at 37 sites. At 60 sites we measured 18 habitat variables regarding slope, aspect, tree species, shrub species, and ground cover. We used logistic regression to analyze habitat variables associated with chipmunk presence/absence. All (100%) 37 sample sites (28 predicted suitable, 9 predicted unsuitable) were classified correctly by the GIS model regarding elevation and vegetation. For 28 sites predicted suitable by the GIS model, 18 sites (64%) appeared visually suitable based on habitat variables selected from logistic regression analyses, of which 10 sites (36%) were specifically predicted as suitable habitat via logistic regression. We detected chipmunks at 70% of sites deemed suitable via the logistic regression models. Shrub cover, tree density, plant proximity, presence of logs, and presence of rock outcrop were retained in the logistic model for the Oscura Mountains; litter, shrub cover, and grass cover were retained in the logistic model for the Organ Mountains. Evaluation of predictive models illustrates the need for multi-stage analyses to best judge performance. Microhabitat analyses indicate prospective needs for different management strategies between the subspecies. Sensitivities of each population of the Colorado chipmunk to natural and prescribed fire suggest that partial burnings of areas inhabited by Colorado chipmunks in southern New Mexico may be beneficial. These partial burnings may later help avoid a fire

  3. Instream Physical Habitat Modelling Types

    DEFF Research Database (Denmark)

    Conallin, John; Boegh, Eva; Krogsgaard, Jørgen

    2010-01-01

    The introduction of the EU Water Framework Directive (WFD) is providing member state water resource managers with significant challenges in relation to meeting the deadline for 'Good Ecological Status' by 2015. Overall, instream physical habitat modelling approaches have advantages and disadvanta......The introduction of the EU Water Framework Directive (WFD) is providing member state water resource managers with significant challenges in relation to meeting the deadline for 'Good Ecological Status' by 2015. Overall, instream physical habitat modelling approaches have advantages...... suit their situations. This paper analyses the potential of different methods available for water managers to assess hydrological and geomorphological impacts on the habitats of stream biota, as requested by the WFD. The review considers both conventional and new advanced research-based instream...... physical habitat models. In parametric and non-parametric regression models, model assumptions are often not satisfied and the models are difficult to transfer to other regions. Research-based methods such as the artificial neural networks and individual-based modelling have promising potential as water...

  4. Análise das variações florísticas e estruturais da comunidade arbórea de um fragmento de floresta semidecídua às margens do rio Capivari, Lavras-MG

    Directory of Open Access Journals (Sweden)

    Souza Josival Santos

    2003-01-01

    Full Text Available Realizou-se um estudo das variações florísticas e estruturais da comunidade arbórea em um fragmento de Floresta Estacional Semidecídua situado às margens do rio Capivari, em Lavras, Minas Gerais, com o objetivo de analisar as correlações entre variáveis ambientais (edáficas, topográficas e morfométricas do fragmento e a distribuição das espécies arbóreas. Procurou-se, também, ampliar o conhecimento sobre a composição florística e a estrutura fitossociológica das comunidades arbóreas da região do alto rio Grande. As espécies arbóreas foram amostradas em coletas extensivas na área e intensivas dentro de 28 parcelas de 20 20 m, tendo sido considerados apenas os indivíduos com DAP > 5 cm. As parcelas foram distribuídas em cinco transeções, dispostas paralelamente à inclinação predominante do terreno. As variáveis ambientais foram obtidas por meio do levantamento topográfico do fragmento e de análises químicas e granulométricas de amostras dos solos. As correlações entre distribuição das abundâncias das espécies e as variáveis ambientais nas parcelas foram avaliadas por análise de correspondência canônica (CCA. A listagem florística registrou 166 espécies, sendo 140 encontradas dentro das parcelas. A comunidade arbórea apresentou um elevado índice de diversidade de Shannon (H' = 4,258 nats/indivíduo, correlacionado à baixa dominância ecológica (alta equabilidade de Pielou, J' = 0,862 e, possivelmente, à alta heterogeneidade ambiental local. A CCA demonstrou que a heterogeneidade ambiental do fragmento é caracterizada principalmente pela topografia acidentada e pelas variações de fertilidade, granulometria e regime hídrico dos solos, sendo este último o mais fortemente correlacionado com a distribuição das espécies. Muitas espécies arbóreas mostraram clara preferência por dois habitats: a baixa encosta, com solos mais úmidos e férteis, e a alta encosta, com solos menos úmidos e f

  5. Distribution, habitat and adaptability of the genus Tapirus.

    Science.gov (United States)

    García, Manolo J; Medici, Emília Patrícia; Naranjo, Eduardo J; Novarino, Wilson; Leonardo, Raquel S

    2012-12-01

    In this manuscript, as a starting point, the ancient and current distribution of the genus Tapirus are summarized, from its origins, apparently in Europe, to current ranges. Subsequently, original and current tapir habitats are described, as well as changes in ancient habitats. As the manuscript goes on, we examine the ways in which tapir species interact with their habitats and the main aspects of habitat use, spatial ecology and adaptability. Having reviewed the historic and current distribution of tapirs, as well as their use and selection of habitats, we introduce the concept of adaptability, considering that some of the tapir physiological characteristics and behavioral strategies can reduce the negative impact of habitat alteration and climate change. Finally, we provide recommendations for future research priorities. The conservation community is still missing important pieces of information for the effective conservation of tapirs and their remaining habitats in Central and South America and Southeast Asia. Reconstructing how tapir species reached their current distribution ranges, interpreting how they interact with their habitats and gathering information regarding the strategies they use to cope with habitat changes will increase our understanding about these animals and contribute to the development of conservation strategies. © 2012 Wiley Publishing Asia Pty Ltd, ISZS and IOZ/CAS.

  6. Habitat stability, predation risk and ‘memory syndromes’

    Science.gov (United States)

    Dalesman, S.; Rendle, A.; Dall, S.R.X.

    2015-01-01

    Habitat stability and predation pressure are thought to be major drivers in the evolutionary maintenance of behavioural syndromes, with trait covariance only occurring within specific habitats. However, animals also exhibit behavioural plasticity, often through memory formation. Memory formation across traits may be linked, with covariance in memory traits (memory syndromes) selected under particular environmental conditions. This study tests whether the pond snail, Lymnaea stagnalis, demonstrates consistency among memory traits (‘memory syndrome’) related to threat avoidance and foraging. We used eight populations originating from three different habitat types: i) laboratory populations (stable habitat, predator-free); ii) river populations (fairly stable habitat, fish predation); and iii) ditch populations (unstable habitat, invertebrate predation). At a population level, there was a negative relationship between memories related to threat avoidance and food selectivity, but no consistency within habitat type. At an individual level, covariance between memory traits was dependent on habitat. Laboratory populations showed no covariance among memory traits, whereas river populations showed a positive correlation between food memories, and ditch populations demonstrated a negative relationship between threat memory and food memories. Therefore, selection pressures among habitats appear to act independently on memory trait covariation at an individual level and the average response within a population. PMID:26013966

  7. Food technology in space habitats

    Science.gov (United States)

    Karel, M.

    1979-01-01

    The research required to develop a system that will provide for acceptable, nutritious, and safe diets for man during extended space missions is discussed. The development of a food technology system for space habitats capable of converting raw materials produced in the space habitats into acceptable food is examined.

  8. Ophiuroidea das regiões antartica e subantartica: 2. variação em Gorgonocephalus chílensis (Philippi (Echinodermata, Ophiuroidea, Gorgonocephalidae Ophiuroidea from antarctic and subantarctic regions: 2. variation on Gorgonocephalus chilensis (Philippi (Echinodermata, Ophiuroidea, Gorgonocephalidae

    Directory of Open Access Journals (Sweden)

    Ana Maria Gouveia Monteiro

    1983-01-01

    Full Text Available Foram examinados 198 exemplares de Gorgonocephalus chilensis das regiões antártica e subantartica, tendo-se em vista a variação de caracteres morfológicos externos. Foi constatada uma grande variação nas características morfológicas externas, que parece independer de localização geográfica.A revision is presented on the variability of the ornamentation and other extermal morphological aspects of Gorgonocephalus chilensis. The samples were obtained along the period of 1962 to 1972 by the R/V "Hero" and "Eltanin" (USARP and by the R/V "Almirante Saldanha" from the Brazilian Navy.

  9. Decomposição estrutural da variação do emprego nos setores industriais no brasil entre os anos de 2000 e 2009

    Directory of Open Access Journals (Sweden)

    Carina Diane Nakatani-Macedo

    2015-08-01

    Full Text Available RESUMO O objetivo do presente artigo é analisar a variação de emprego nos setores industriais nos anos 2000-2009 para o Brasil. Utiliza-se a metodologia de insumo-pro­duto, através da decomposição estrutural da variação do emprego em efeitos de intensidade, de tecnologia, da demanda, do crescimento e total. Os principais resultados mostraram que entre os dois períodos estudados, houve um acréscimo de 4,39 milhões de vagas para o setor industrial que isoladamente foi responsável por, aproximadamente, 25% do resultado nacional. Dentre os efeitos estudados pode-se destacar o efeito crescimento e intensidade como principal responsável pelos resultados. Ao considerar o efeito total, os setores que apresentaram maior crescimento relativo no número de empregos foram os de alimentos e bebidas, artigos do vestuário e acessórios e construção civil. Os resultados obtidos permitiram concluir que houve um aumento do número de postos de trabalho para a indústria no Brasil no período analisado, onde a tecnologia, apesar de não explicar unicamente o efeito crescimento, mostra impactos positivos na geração de emprego no efeito total.

  10. Environmental variation and habitat separation among small mammals

    International Nuclear Information System (INIS)

    Vickery, W.L.; Iverson, S.L.; Mihok, S.; Schwartz, B.

    1989-01-01

    Habitat use and population density of five species of forest small mammals were monitored by annual spring snap-trap censuses at Pinawa, Manitoba, over 14 years. Population sizes were positively correlated among species and showed no evidence of density-dependent effects. Species were habitat selectors. Habitat use by species did not vary among years. Habitat separation between the dominant species was not correlated with environmental variables or with population size. We suggest that habitat selection and positive covariance among species abundances are the principal factors characterizing the dynamics of this community

  11. Mourning Dove nesting habitat and nest success in Central Missouri

    Science.gov (United States)

    Drobney, R.D.; Schulz, J.H.; Sheriff, S.L.; Fuemmeler, W.J.

    1998-01-01

    Previous Mourning Dove (Zenaida macroura) nesting studies conducted in areas containing a mixture of edge and continuous habitats have focused on edge habitats. Consequently, little is known about the potential contribution of continuous habitats to dove production. In this study we evaluated the relative importance of these two extensive habitat types by monitoring the habitat use and nest success of 59 radio-marked doves during 1990-1991 in central Missouri. Of 83 nests initiated by our marked sample, most (81.9%) were located in edge habitats. Although continuous habitats were selected less as nest sites, the proportion of successful nests did not differ significantly from that in edge habitats. Our data indicate that continuous habitats should not be considered marginal nesting habitat. If the intensity of use and nest success that we observed are representative regionally or nationally, continuous habitats could contribute substantially to annual Mourning Dove production because of the high availability of these habitats throughout much of the Mourning Dove breeding range.

  12. A test of the substitution-habitat hypothesis in amphibians.

    Science.gov (United States)

    Martínez-Abraín, Alejandro; Galán, Pedro

    2017-12-08

    Most examples that support the substitution-habitat hypothesis (human-made habitats act as substitutes of original habitat) deal with birds and mammals. We tested this hypothesis in 14 amphibians by using percentage occupancy as a proxy of habitat quality (i.e., higher occupancy percentages indicate higher quality). We classified water body types as original habitat (no or little human influence) depending on anatomical, behavioral, or physiological adaptations of each amphibian species. Ten species had relatively high probabilities (0.16-0.28) of occurrence in original habitat, moderate probability of occurrence in substitution habitats (0.11-0.14), and low probability of occurrence in refuge habitats (0.05-0.08). Thus, the substitution-habitat hypothesis only partially applies to amphibians because the low occupancy of refuges could be due to the negligible human persecution of this group (indicating good conservation status). However, low occupancy of refuges could also be due to low tolerance of refuge conditions, which could have led to selective extinction or colonization problems due to poor dispersal capabilities. That original habitats had the highest probabilities of occupancy suggests amphibians have a good conservation status in the region. They also appeared highly adaptable to anthropogenic substitution habitats. © 2017 Society for Conservation Biology.

  13. Physical habitat classification and instream flow modeling to determine habitat availability during low-flow periods, North Fork Shenandoah River, Virginia

    Science.gov (United States)

    Krstolic, Jennifer L.; Hayes, Donald C.; Ruhl, Peter M.

    2006-01-01

    Increasing development and increasing water withdrawals for public, industrial, and agricultural water supply threaten to reduce streamflows in the Shenandoah River basin in Virginia. Water managers need more information to balance human water-supply needs with the daily streamflows necessary for maintaining the aquatic ecosystems. To meet the need for comprehensive information on hydrology, water supply, and instream-flow requirements of the Shenandoah River basin, the U.S. Geological Survey and the Northern Shenandoah Valley Regional Commission conducted a cooperative investigation of habitat availability during low-flow periods on the North Fork Shenandoah River. Historic streamflow data and empirical data on physical habitat, river hydraulics, fish community structure, and recreation were used to develop a physical habitat simulation model. Hydraulic measurements were made during low, medium, and high flows in six reaches at a total of 36 transects that included riffles, runs, and pools, and that had a variety of substrates and cover types. Habitat suitability criteria for fish were developed from detailed fish-community sampling and microhabitat observations. Fish were grouped into four guilds of species and life stages with similar habitat requirements. Simulated habitat was considered in the context of seasonal flow regimes to show the availability of flows that sustain suitable habitat during months when precipitation and streamflow are scarce. The North Fork Shenandoah River basin was divided into three management sections for analysis purposes: the upper section, middle section, and lower section. The months of July, August, and September were chosen to represent a low-flow period in the basin with low mean monthly flows, low precipitation, high temperatures, and high water withdrawals. Exceedance flows calculated from the combined data from these three months describe low-flow periods on the North Fork Shenandoah River. Long-term records from three

  14. Habitat modeling for biodiversity conservation.

    Science.gov (United States)

    Bruce G. Marcot

    2006-01-01

    Habitat models address only 1 component of biodiversity but can be useful in addressing and managing single or multiple species and ecosystem functions, for projecting disturbance regimes, and in supporting decisions. I review categories and examples of habitat models, their utility for biodiversity conservation, and their roles in making conservation decisions. I...

  15. Modeling the flocking propensity of passerine birds in two Neotropical habitats.

    Science.gov (United States)

    Pomara, Lars Y; Cooper, Robert J; Petit, Lisa J

    2007-08-01

    We examined the importance of mixed-species flock abundance, individual bird home range size, foraging height, and foraging patch characteristics in predicting the propensity for five Neotropical passerine bird species (Slaty Antwren, Myrmotherula schisticolor; Golden-crowned Warbler, Basileuterus culicivorus; Slate-throated Redstart, Myioborus miniatus; Wilson's Warbler, Wilsonia pusilla; and Black-and-white Warbler, Mniotilta varia) to forage within flocks, rather than solitarily. We used study plots in primary mid-elevation forest and in shade coffee fields in western Panama. We expected that all species would spend as much time as possible flocking, but that the social and environmental factors listed above would limit compatibility between flock movements and individual bird movements, explaining variability in flocking propensity both within and among species. Flocking propensity was well predicted by home range size and flock abundance together, for four of the five species. While flock abundance was uniform across plots, home range sizes varied among species and plots, so that home range size appeared to be the principle factor limiting flocking propensity. Estimates of flock abundance were still required, however, for calculating flocking propensity values. Foraging height and patch characteristics slightly improved predictive ability for the remaining species, M. miniatus. In general, individual birds tended to join flocks whenever one was available inside their home range, regardless of a flock's specific location within the home range. Flocking propensities of individual species were lower in shade coffee fields than in forests, and probably vary across landscapes with variations in habitat. This variability affects the stability and species composition of flocks, and may affect survival rates of individual species.

  16. Partitioning mechanisms of predator interference in different habitats.

    Science.gov (United States)

    Griffen, Blaine D; Byers, James E

    2006-01-01

    Prey are often consumed by multiple predator species. Predation rates on shared prey species measured in isolation often do not combine additively due to interference or facilitation among the predator species. Furthermore, the strength of predator interactions and resulting prey mortality may change with habitat type. We experimentally examined predation on amphipods in rock and algal habitats by two species of intertidal crabs, Hemigrapsus sanguineus (top predators) and Carcinus maenas (intermediate predators). Algae provided a safer habitat for amphipods when they were exposed to only a single predator species. When both predator species were present, mortality of amphipods was less than additive in both habitats. However, amphipod mortality was reduced more in rock than algal habitat because intermediate predators were less protected in rock habitat and were increasingly targeted by omnivorous top predators. We found that prey mortality in general was reduced by (1) altered foraging behavior of intermediate predators in the presence of top predators, (2) top predators switching to foraging on intermediate predators rather than shared prey, and (3) density reduction of intermediate predators. The relative importance of these three mechanisms was the same in both habitats; however, the magnitude of each was greater in rock habitat. Our study demonstrates that the strength of specific mechanisms of interference between top and intermediate predators can be quantified but cautions that these results may be habitat specific.

  17. Restricted cross-scale habitat selection by American beavers.

    Science.gov (United States)

    Francis, Robert A; Taylor, Jimmy D; Dibble, Eric; Strickland, Bronson; Petro, Vanessa M; Easterwood, Christine; Wang, Guiming

    2017-12-01

    Animal habitat selection, among other ecological phenomena, is spatially scale dependent. Habitat selection by American beavers Castor canadensis (hereafter, beaver) has been studied at singular spatial scales, but to date no research addresses multi-scale selection. Our objectives were to determine if beaver habitat selection was specialized to semiaquatic habitats and if variables explaining habitat selection are consistent between landscape and fine spatial scales. We built maximum entropy (MaxEnt) models to relate landscape-scale presence-only data to landscape variables, and used generalized linear mixed models to evaluate fine spatial scale habitat selection using global positioning system (GPS) relocation data. Explanatory variables between the landscape and fine spatial scale were compared for consistency. Our findings suggested that beaver habitat selection at coarse (study area) and fine (within home range) scales was congruent, and was influenced by increasing amounts of woody wetland edge density and shrub edge density, and decreasing amounts of open water edge density. Habitat suitability at the landscape scale also increased with decreasing amounts of grass frequency. As territorial, central-place foragers, beavers likely trade-off open water edge density (i.e., smaller non-forested wetlands or lodges closer to banks) for defense and shorter distances to forage and obtain construction material. Woody plants along edges and expanses of open water for predator avoidance may limit beaver fitness and subsequently determine beaver habitat selection.

  18. Habitat specialization in tropical continental shelf demersal fish assemblages.

    Directory of Open Access Journals (Sweden)

    Ben M Fitzpatrick

    Full Text Available The implications of shallow water impacts such as fishing and climate change on fish assemblages are generally considered in isolation from the distribution and abundance of these fish assemblages in adjacent deeper waters. We investigate the abundance and length of demersal fish assemblages across a section of tropical continental shelf at Ningaloo Reef, Western Australia, to identify fish and fish habitat relationships across steep gradients in depth and in different benthic habitat types. The assemblage composition of demersal fish were assessed from baited remote underwater stereo-video samples (n = 304 collected from 16 depth and habitat combinations. Samples were collected across a depth range poorly represented in the literature from the fringing reef lagoon (1-10 m depth, down the fore reef slope to the reef base (10-30 m depth then across the adjacent continental shelf (30-110 m depth. Multivariate analyses showed that there were distinctive fish assemblages and different sized fish were associated with each habitat/depth category. Species richness, MaxN and diversity declined with depth, while average length and trophic level increased. The assemblage structure, diversity, size and trophic structure of demersal fishes changes from shallow inshore habitats to deeper water habitats. More habitat specialists (unique species per habitat/depth category were associated with the reef slope and reef base than other habitats, but offshore sponge-dominated habitats and inshore coral-dominated reef also supported unique species. This suggests that marine protected areas in shallow coral-dominated reef habitats may not adequately protect those species whose depth distribution extends beyond shallow habitats, or other significant elements of demersal fish biodiversity. The ontogenetic habitat partitioning which is characteristic of many species, suggests that to maintain entire species life histories it is necessary to protect corridors of

  19. Sex- and habitat-specific movement of an omnivorous semi-terrestrial crab controls habitat connectivity and subsidies: a multi-parameter approach.

    Science.gov (United States)

    Hübner, Lena; Pennings, Steven C; Zimmer, Martin

    2015-08-01

    Distinct habitats are often linked through fluxes of matter and migration of organisms. In particular, intertidal ecotones are prone to being influenced from both the marine and the terrestrial realms, but whether or not small-scale migration for feeding, sheltering or reproducing is detectable may depend on the parameter studied. Within the ecotone of an upper saltmarsh in the United States, we investigated the sex-specific movement of the semi-terrestrial crab Armases cinereum using an approach of determining multiple measures of across-ecotone migration. To this end, we determined food preference, digestive abilities (enzyme activities), bacterial hindgut communities (genetic fingerprint), and the trophic position of Armases and potential food sources (stable isotopes) of males versus females of different sub-habitats, namely high saltmarsh and coastal forest. Daily observations showed that Armases moved frequently between high-intertidal (saltmarsh) and terrestrial (forest) habitats. Males were encountered more often in the forest habitat, whilst gravid females tended to be more abundant in the marsh habitat but moved more frequently. Food preference was driven by both sex and habitat. The needlerush Juncus was preferred over three other high-marsh detrital food sources, and the periwinkle Littoraria was the preferred prey of male (but not female) crabs from the forest habitats; both male and female crabs from marsh habitat preferred the fiddler crab Uca over three other prey items. In the field, the major food sources were clearly vegetal, but males have a higher trophic position than females. In contrast to food preference, isotope data excluded Uca and Littoraria as major food sources, except for males from the forest, and suggested that Armases consumes a mix of C4 and C3 plants along with animal prey. Digestive enzyme activities differed significantly between sexes and habitats and were higher in females and in marsh crabs. The bacterial hindgut community

  20. Beaked Whale Habitat Characterization and Prediction

    National Research Council Canada - National Science Library

    Ward, Jessica A; Mitchell, Glenn H; Farak, Amy M; Keane, Ellen P

    2005-01-01

    The objective of this study was to characterize known beaked whale habitat and create a predictive beaked whale habitat model of the Gulf of Mexico and east coast of the United States using available...

  1. Pacific Northwest Salmon Habitat Project Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In the Pacific Northwest Salmon Habitat Project Database Across the Pacific Northwest, both public and private agents are working to improve riverine habitat for a...

  2. A technical guide for monitoring wildlife habitat

    Science.gov (United States)

    M.M. Rowland; C.D. Vojta

    2013-01-01

    Information about status and trend of wildlife habitat is important for the U.S. Department of Agriculture, Forest Service to accomplish its mission and meet its legal requirements. As the steward of 193 million acres (ac) of Federal land, the Forest Service needs to evaluate the status of wildlife habitat and how it compares with desired conditions. Habitat monitoring...

  3. Clay Animals and Their Habitats

    Science.gov (United States)

    Adamson, Kay

    2010-01-01

    Creating clay animals and their habitats with second-grade students has long been one of the author's favorite classroom activities. Students love working with clay and they also enjoy drawing animal homes. In this article, the author describes how the students created a diorama instead of drawing their clay animal's habitat. This gave students…

  4. Interfacing models of wildlife habitat and human development to predict the future distribution of puma habitat

    Science.gov (United States)

    Burdett, Christopher L.; Crooks, Kevin R.; Theobald, David M.; Wilson, Kenneth R.; Boydston, Erin E.; Lyren, Lisa A.; Fisher, Robert N.; Vickers, T. Winston; Morrison, Scott A.; Boyce, Walter M.

    2010-01-01

    The impact of human land uses on ecological systems typically differ relative to how extensively natural conditions are modified. Exurban development is intermediate-intensity residential development that often occurs in natural landscapes. Most species-habitat models do not evaluate the effects of such intermediate levels of human development and even fewer predict how future development patterns might affect the amount and configuration of habitat. We addressed these deficiencies by interfacing a habitat model with a spatially-explicit housing-density model to study the effect of human land uses on the habitat of pumas (Puma concolor) in southern California. We studied the response of pumas to natural and anthropogenic features within their home ranges and how mortality risk varied across a gradient of human development. We also used our housing-density model to estimate past and future housing densities and model the distribution of puma habitat in 1970, 2000, and 2030. The natural landscape for pumas in our study area consisted of riparian areas, oak woodlands, and open, conifer forests embedded in a chaparral matrix. Pumas rarely incorporated suburban or urban development into their home ranges, which is consistent with the hypothesis that the behavioral decisions of individuals can be collectively manifested as population-limiting factors at broader spatial scales. Pumas incorporated rural and exurban development into their home ranges, apparently perceiving these areas as modified, rather than non-habitat. Overall, pumas used exurban areas less than expected and showed a neutral response to rural areas. However, individual pumas that selected for or showed a neutral response to exurban areas had a higher risk of mortality than pumas that selected against exurban habitat. Exurban areas are likely hotspots for puma-human conflict in southern California. Approximately 10% of our study area will transform from exurban, rural, or undeveloped areas to suburban or

  5. Somaclonal variation in micropropagated Heliconia bihai cv. Lobster Claw I plantlets (Heliconiaceae Variação somaclonal em mudas micropropagadas de Helicônia, Heliconia Bihai cv. Lobster Claw I (Heliconiaceae

    Directory of Open Access Journals (Sweden)

    Paulo Hercílio Viegas Rodrigues

    2008-12-01

    Full Text Available The occurrence of somaclonal variation is described in various cultures of agronomic interest. Such variation can be of benefit in the development of new flower varieties. In this study, the occurrence of somaclonal variation in micropropagated changes of Heliconia bihai cv. Lobster Claw I was investigated. Stem apexes were introduced in MS culture media with the addition of 2.5 mg L-1 of benzylaminopure (BAP and 500 mg L-1 of sodium cefotaxime. After selecting the apex stem, it was sub-cultivated in MS media and supplemented with 4.0 mg L-1 of BAP to induce side buds. To conduct the trial, 2,000 plants were selected and compared with plants originated from rhizomes. To calculate the percentage of the variants, the plant stature, the form and color of leaves and pseudostem were evaluated. The plants with buds presenting the same type of variation were considered as variants. The occurrence of three types of somaclonal variants was observed: Variation of the Chlorophyll in the Leaf, Low Stature Variant and Pseudostem and Petiole Color Variant, the latter with ornamental potential. The somaclonal variation rate for Heliconia bihai cv Lobster Claw I, under the proposed conditions, was 61.40%.A ocorrência de variação somaclonal é descrita em diversas culturas de interesse agronômico. A floricultura pode beneficiar-se dessa variabilidade, com a obtenção de novas variedades. Nesse trabalho, estudou-se a ocorrência de variação somaclonal em mudas micropropagadas de Heliconia bihai cv. Lobster Claw I. Ápices caulinares foram introduzidos em meio de cultivo MS com adição de 2,5 mg L-1 de benzilaminopurina (BAP e 500 mg L-1 de cefotaxima sódica. Após a seleção do ápice caulinar, o explante foi subcultivado em meio MS suplementado com 4,0 mg L-1 de BAP para indução de brotações. Foram selecionadas, ao acaso, 2.000 mudas e comparadas com mudas originadas de rizomas, para compor o ensaio. No cálculo da porcentagem dos variantes

  6. Trapping Triatominae in Silvatic Habitats

    Directory of Open Access Journals (Sweden)

    Noireau François

    2002-01-01

    Full Text Available Large-scale trials of a trapping system designed to collect silvatic Triatominae are reported. Live-baited adhesive traps were tested in various ecosystems and different triatomine habitats (arboreal and terrestrial. The trials were always successful, with a rate of positive habitats generally over 20% and reaching 48.4% for palm trees of the Amazon basin. Eleven species of Triatominae belonging to the three genera of public health importance (Triatoma, Rhodnius and Panstrongylus were captured. This trapping system provides an effective way to detect the presence of triatomines in terrestrial and arboreal silvatic habitats and represents a promising tool for ecological studies. Various lines of research are contemplated to improve the performance of this trapping system.

  7. Determinants of Habitat Selection by Hatchling Australian Freshwater Crocodiles

    Science.gov (United States)

    Somaweera, Ruchira; Webb, Jonathan K.; Shine, Richard

    2011-01-01

    Animals almost always use habitats non-randomly, but the costs and benefits of using specific habitat types remain unknown for many types of organisms. In a large lake in northwestern Australia (Lake Argyle), most hatchling (banks rather than the more widely available open banks. Mean body sizes of young crocodiles did not differ among the three habitat types. We tested four potential explanations for non-random habitat selection: proximity to nesting sites, thermal conditions, food availability, and exposure to predation. The three alternative habitat types did not differ in proximity to nesting sites, or in thermal conditions. Habitats with higher food availability harboured more hatchlings, and feeding rates (obtained by stomach-flushing of recently-captured crocodiles) were highest in such areas. Predation risk may also differ among habitats: we were twice as likely to capture a crocodile after seeing it in open-bank sites than in the other two habitat types. Thus, habitat selection of hatchling crocodiles in this system may be driven both by prey availability and by predation risk. PMID:22163308

  8. Development of a Regional Habitat Classification Scheme for the ...

    African Journals Online (AJOL)

    development, image processing techniques and field survey methods are outlined. Habitat classification, and regional-scale comparisons of relative habitat composition are described. The study demonstrates the use of remote sensing data to construct digital habitat maps for the comparison of regional habitat coverage, ...

  9. CisLunar Habitat Internal Architecture Design Criteria

    Science.gov (United States)

    Jones, R.; Kennedy, K.; Howard, R.; Whitmore, M.; Martin, C.; Garate, J.

    2017-01-01

    BACKGROUND: In preparation for human exploration to Mars, there is a need to define the development and test program that will validate deep space operations and systems. In that context, a Proving Grounds CisLunar habitat spacecraft is being defined as the next step towards this goal. This spacecraft will operate differently from the ISS or other spacecraft in human history. The performance envelope of this spacecraft (mass, volume, power, specifications, etc.) is being defined by the Future Capabilities Study Team. This team has recognized the need for a human-centered approach for the internal architecture of this spacecraft and has commissioned a CisLunar Phase-1 Habitat Internal Architecture Study Team to develop a NASA reference configuration, providing the Agency with a "smart buyer" approach for future acquisition. THE CISLUNAR HABITAT INTERNAL ARCHITECTURE STUDY: Overall, the CisLunar Habitat Internal Architecture study will address the most significant questions and risks in the current CisLunar architecture, habitation, and operations concept development. This effort is achieved through definition of design criteria, evaluation criteria and process, design of the CisLunar Habitat Phase-1 internal architecture, and the development and fabrication of internal architecture concepts combined with rigorous and methodical Human-in-the-Loop (HITL) evaluations and testing of the conceptual innovations in a controlled test environment. The vision of the CisLunar Habitat Internal Architecture Study is to design, build, and test a CisLunar Phase-1 Habitat Internal Architecture that will be used for habitation (e.g. habitability and human factors) evaluations. The evaluations will mature CisLunar habitat evaluation tools, guidelines, and standards, and will interface with other projects such as the Advanced Exploration Systems (AES) Program integrated Power, Avionics, Software (iPAS), and Logistics for integrated human-in-the-loop testing. The mission of the Cis

  10. Habitat selection and management of the Hawaiian crow

    Science.gov (United States)

    Giffen, J.G.; Scott, J.M.; Mountainspring, S.

    1987-01-01

    The abundance and range of the Hawaiian crow, or alala, (Corvus hawaiiensis) have decreased drastically since the 1890's. Fewer than 10 breeding pairs remained in the wild in 1985. A sample of 82 nests during 1970-82 were used to determine habitat associations. Two hundred firty-nine alala observations were used to estimate densities occurring in different vegetation types in 1978. Compared to available habitat, more nests and higher bird densities during the breeding season occurred in areas where: (1) canopy cover was > 60%; (2) koa (Acacia koa) and ohia (Metrosideros polymorpha) were dominant species in the crown layer; (3) native plants constituted > 75% of the understory cover; and (4) the elevation was 1,100-1,500 m. Compared to breeding habitat, nonbreeding habitat tended to lie at lower elevations and in wetter forests having the crown layer dominated by ohia but lacking koa. Habitat loss is a major factor underlying the decline of this species although predation on fledgings, avian disease, and shooting also have reduced the population. Remaining key habitat areas have little or no legal protection through zoning and land ownership. Preserves should be established to encompass the location of existing pairs and to assure the provision of optimum breeding habitat and suitable nonbreeding habitat.

  11. Does habitat variability really promote metabolic network modularity?

    Science.gov (United States)

    Takemoto, Kazuhiro

    2013-01-01

    The hypothesis that variability in natural habitats promotes modular organization is widely accepted for cellular networks. However, results of some data analyses and theoretical studies have begun to cast doubt on the impact of habitat variability on modularity in metabolic networks. Therefore, we re-evaluated this hypothesis using statistical data analysis and current metabolic information. We were unable to conclude that an increase in modularity was the result of habitat variability. Although horizontal gene transfer was also considered because it may contribute for survival in a variety of environments, closely related to habitat variability, and is known to be positively correlated with network modularity, such a positive correlation was not concluded in the latest version of metabolic networks. Furthermore, we demonstrated that the previously observed increase in network modularity due to habitat variability and horizontal gene transfer was probably due to a lack of available data on metabolic reactions. Instead, we determined that modularity in metabolic networks is dependent on species growth conditions. These results may not entirely discount the impact of habitat variability and horizontal gene transfer. Rather, they highlight the need for a more suitable definition of habitat variability and a more careful examination of relationships of the network modularity with horizontal gene transfer, habitats, and environments.

  12. Variação inter-individual nos níveis de bilirrubina: o papel dos factores genéticos e adquiridos

    OpenAIRE

    Rodrigues, Carina; Vieira, Emília; Santos, Rosário; Carvalho, João; Santos-Silva, Alice; Elísio, Costa; Bronze-da-Rocha, Elsa

    2011-01-01

    A bilirrubina é um pigmento biliar que deriva principalmente do catabolismo da hemoglobina. É um marcador bioquímico de doenças hepáticas e hematológicas e tem vindo a ser alvo de interesse devido à sua capacidade antioxidante. O objectivo deste trabalho foi avaliar a contribuição de vários factores para a variação da concentração da bilirrubina sérica na população portuguesa. Foi analisado o contributo dos polimorfismo genéticos no promotor do gene UGT1A1 (c.-41_40...

  13. Gulf-Wide Information System, Environmental Sensitivity Index Habitats Database, Geographic NAD83, LDWF (2001) [esi_habitats_LDWF_2001

    Data.gov (United States)

    Louisiana Geographic Information Center — This data set contains sensitive biological resource data for coastal habitats in Louisiana. Vector polygons represent various habitats, including marsh types, other...

  14. Habitat connectivity and fragmented nuthatch populations in agricultural landscapes

    NARCIS (Netherlands)

    Langevelde, van F.

    1999-01-01

    In agricultural landscapes, the habitat of many species is subject to fragmentation. When the habitat of a species is fragmented and the distances between patches of habitat are large relative to the movement distances of the species, it can be expected that the degree of habitat

  15. Habitat connectivity and ecosystem productivity: implications from a simple model.

    Science.gov (United States)

    Cloern, James E

    2007-01-01

    The import of resources (food, nutrients) sustains biological production and food webs in resource-limited habitats. Resource export from donor habitats subsidizes production in recipient habitats, but the ecosystem-scale consequences of resource translocation are generally unknown. Here, I use a nutrient-phytoplankton-zooplankton model to show how dispersive connectivity between a shallow autotrophic habitat and a deep heterotrophic pelagic habitat can amplify overall system production in metazoan food webs. This result derives from the finite capacity of suspension feeders to capture and assimilate food particles: excess primary production in closed autotrophic habitats cannot be assimilated by consumers; however, if excess phytoplankton production is exported to food-limited heterotrophic habitats, it can be assimilated by zooplankton to support additional secondary production. Transport of regenerated nutrients from heterotrophic to autotrophic habitats sustains higher system primary production. These simulation results imply that the ecosystem-scale efficiency of nutrient transformation into metazoan biomass can be constrained by the rate of resource exchange across habitats and that it is optimized when the transport rate matches the growth rate of primary producers. Slower transport (i.e., reduced connectivity) leads to nutrient limitation of primary production in autotrophic habitats and food limitation of secondary production in heterotrophic habitats. Habitat fragmentation can therefore impose energetic constraints on the carrying capacity of aquatic ecosystems. The outcomes of ecosystem restoration through habitat creation will be determined by both functions provided by newly created aquatic habitats and the rates of hydraulic connectivity between them.

  16. Habitat connectivity as a metric for aquatic microhabitat quality: Application to Chinook salmon spawning habitat

    Science.gov (United States)

    Ryan Carnie; Daniele Tonina; Jim McKean; Daniel Isaak

    2016-01-01

    Quality of fish habitat at the scale of a single fish, at the metre resolution, which we defined here as microhabitat, has been primarily evaluated on short reaches, and their results have been extended through long river segments with methods that do not account for connectivity, a measure of the spatial distribution of habitat patches. However, recent...

  17. Fish habitat mitigation measures for hydrotechnical projects

    International Nuclear Information System (INIS)

    McPhail, G.D.; MacMillan, D.B.; Katopodis, C.

    1992-01-01

    In recent years, the identification and mitigation of environmental impacts of hydrotechnical projects, particularly on fish and fish habitats, have become a major component of project planning and design. Potential impacts to fish and fish habitat may include increased fish mortality, decreased species diversity, and loss or decreases in fish production due to loss of habitat or alteration of its suitability. These impacts arise from flooding of riverine habitat, alteration of flow quantity and distribution, changes in morphology, and alteration of water quality, including suspended sediments, temperature, dissolved oxygen, and mercury. The results of a study for the Canadian Federal Department of Fisheries and Oceans Central and Arctic Region, examining fish habitat mitigation techniques for their applicability to hydrotechnical projects in Canada are summarized. The requirements for achievement and verification of the no net loss policy for a project are discussed. 10 refs., 2 tabs

  18. Prisoners in their habitat? Generalist dispersal by habitat specialists: a case study in southern water vole (Arvicola sapidus.

    Directory of Open Access Journals (Sweden)

    Alejandro Centeno-Cuadros

    Full Text Available Habitat specialists inhabiting scarce and scattered habitat patches pose interesting questions related to dispersal such as how specialized terrestrial mammals do to colonize distant patches crossing hostile matrices. We assess dispersal patterns of the southern water vole (Arvicola sapidus, a habitat specialist whose habitat patches are distributed through less than 2% of the study area (overall 600 km² and whose populations form a dynamic metapopulational network. We predict that individuals will require a high ability to move through the inhospitable matrix in order to avoid genetic and demographic isolations. Genotypes (N = 142 for 10 microsatellites and sequences of the whole mitochondrial Control Region (N = 47 from seven localities revealed a weak but significant genetic structure partially explained by geographic distance. None of the landscape models had a significant effect on genetic structure over that of the Euclidean distance alone and no evidence for efficient barriers to dispersal was found. Contemporary gene flow was not severely limited for A. sapidus as shown by high migration rates estimates (>10% between non-neighbouring areas. Sex-biased dispersal tests did not support differences in dispersal rates, as shown by similar average axial parent-offspring distances, in close agreement with capture-mark-recapture estimates. As predicted, our results do not support any preferences of the species for specific landscape attributes on their dispersal pathways. Here, we combine field and molecular data to illustrate how a habitat specialist mammal might disperse like a habitat generalist, acquiring specific long-distance dispersal strategies as an adaptation to patchy, naturally fragmented, heterogeneous and unstable habitats.

  19. Determinants of habitat selection by hatchling Australian freshwater crocodiles.

    Directory of Open Access Journals (Sweden)

    Ruchira Somaweera

    Full Text Available Animals almost always use habitats non-randomly, but the costs and benefits of using specific habitat types remain unknown for many types of organisms. In a large lake in northwestern Australia (Lake Argyle, most hatchling (<12-month-old freshwater crocodiles (Crocodylus johnstoni are found in floating vegetation mats or grassy banks rather than the more widely available open banks. Mean body sizes of young crocodiles did not differ among the three habitat types. We tested four potential explanations for non-random habitat selection: proximity to nesting sites, thermal conditions, food availability, and exposure to predation. The three alternative habitat types did not differ in proximity to nesting sites, or in thermal conditions. Habitats with higher food availability harboured more hatchlings, and feeding rates (obtained by stomach-flushing of recently-captured crocodiles were highest in such areas. Predation risk may also differ among habitats: we were twice as likely to capture a crocodile after seeing it in open-bank sites than in the other two habitat types. Thus, habitat selection of hatchling crocodiles in this system may be driven both by prey availability and by predation risk.

  20. Habitat connectivity and fragmented nuthatch populations in agricultural landscapes

    OpenAIRE

    Langevelde, van, F.

    1999-01-01

    In agricultural landscapes, the habitat of many species is subject to fragmentation. When the habitat of a species is fragmented and the distances between patches of habitat are large relative to the movement distances of the species, it can be expected that the degree of habitat connectivity affects processes at population and individual level. In this thesis, I report on a study of effects of habitat fragmentation and opportunities to mitigate these effects by planning ecological n...

  1. Prevalence of encysted apicomplexans in muscles of raptors.

    Science.gov (United States)

    Lindsay, D S; Blagburn, B L

    1999-01-28

    An acid-pepsin digestion technique was used to examine portions of breast muscle and heart from raptors for encysted protozoans. Apicomplexan zoites were present in 52 (45.6%) of the 114 samples examined: 11 of 12 (91.7%) red-shouldered hawks (Buteo lineatus), 20 of 34 (58.8%) red-tailed hawks (Buteo jamaicensis), two of seven (28.6%) Cooper's hawks (Accipiter cooperi), three of four (75%) sharp-shinned hawks (Accipiter striatus), one (100%) Mississippi kites (Ictinia misisippiensis), one of two (50%) American kestrels (Falco sparverius), one bald eagle (Haliaeetus leucocephalus), one of two (50%) golden eagles (Aquila chrysaetos), one of three (33%) turkey vultures (Cathartes aura), two of three (66.7%) black vultures (Coragyps atratus), three of six (50%) great-horned owls (Bubo virginianus), five of 15 (33.3%) barred owls (Strix varia), and one of 12 (8.3%) screech owls (Asio otus). Encysted protozoans were not observed in digests of tissues from three broad-winged hawks (Buteo platypterus), four ospreys (Pandion haliaetus), and five barn owls (Tyto alba). Apicomplexan cysts resembling Sarcocystis species were observed in tissue sections of muscles from 28 (37.8%) of 74 raptors.

  2. Effects of experimental removal of Barred Owls on population demography of Northern Spotted Owls in Washington and Oregon—2017 progress report

    Science.gov (United States)

    Wiens, J. David; Dugger, Katie M.; Lesmeister, Damon B.; Dilione, Krista E.; Simon, David C.

    2018-05-21

    Populations of Northern Spotted Owls (Strix occidentalis caurina; hereinafter referred to as Spotted Owl) are declining throughout this subspecies’ geographic range. Evidence indicates that competition with invading populations of Barred Owls (S. varia) has contributed significantly to those declines. A pilot study in California showed that localized removal of Barred Owls coupled with conservation of suitable forest conditions can slow or even reverse population declines of Spotted Owls. It remains unknown, however, whether similar results can be obtained in areas with different forest conditions, greater densities of Barred Owls, and fewer remaining Spotted Owls. During 2015–17, we initiated a before-after-control-impact (BACI) experiment at three study areas in Oregon and Washington to determine if removal of Barred Owls can improve population trends of Spotted Owls. Each study area had at least 20 years of pre-treatment demographic data on Spotted Owls, and represented different forest conditions occupied by the two owl species in the Pacific Northwest. This report describes research accomplishments and preliminary results from the first 2.5 years (March 2015–August 2017) of the planned 5-year experiment.

  3. In situ variation in leaf anatomy and morphology of Andira legalis (Leguminosae in two neighbouring but contrasting light environments in a Brazilian sandy coastal plain Variação in situ em anatomia e morfologia foliar de Andira legalis (Leguminosae em dois ambientes adjacentes, porém contrastantes quanto ao regime de luz, em restinga brasileira

    Directory of Open Access Journals (Sweden)

    Daniela Carvalho Pereira

    2009-03-01

    . Estudos prévios relataram uma grande amplitude de variação morfo-fisiológica para esta espécie ao longo de um gradiente geográfico. Este estudo comparou morfologia e anatomia foliar de A. legalis em dois ambientes adjacentes porém contrastantes quanto ao regime de luz: uma floresta densa (sombreada e uma formação arbustiva de Palmae (exposta à luz. Estudamos a amplitude de variação morfo-anatômica no interior de uma diminuta dimensão geográfica (0,5 ha. Parâmetros de anatomia foliar foram medidos para cinco folhas coletadas a partir de cinco plantas em cada habitat. Os parâmetros avaliados foram: espessura foliar e do mesofilo, espessura da parede celular periclinal externa, espessura adaxial e abaxial da epiderme, área da seção transversal do feixe vascular, e densidade de células epidérmicas comuns, estômatos e tricomas. Dados de morfologia foliar foram obtidos a partir de cinco folhas de cada uma de 20 plantas em cada sítio. Medidas de peso seco e fresco foram tomadas para a obtenção dos valores de massa específica foliar e suculência. Conforme era esperado, os valores de todos os parâmetros anatômicos e morfológicos, exceto densidade de tricomas, foram significativamente mais altos para as plantas expostas ao sol. Menos esperado, entretanto, foi a clara diferença qualitativa entre folhas de plantas expostas vs. sombreadas: nas expostas, o mesofilo apresentou simetria unilateral (i.e., todo o mesofilo era ocupado por tecido fotossintético, enquanto nas sombreadas a simetria foi dorsiventral (i.e., em parte parênquima paliçádico, em parte parênquima esponjoso. Tal amplitude de variação mostra que, mesmo em uma pequena área geográfica, A. legalis tem uma ampla plasticidade ecológica.

  4. The global distribution of deep-water Antipatharia habitat

    Science.gov (United States)

    Yesson, Chris; Bedford, Faye; Rogers, Alex D.; Taylor, Michelle L.

    2017-11-01

    Antipatharia are a diverse group of corals with many species found in deep water. Many Antipatharia are habitat for associates, have extreme longevity and some species can occur beyond 8500 m depth. As they are major constituents of'coral gardens', which are Vulnerable Marine Ecosystems (VMEs), knowledge of their distribution and environmental requirements is an important pre-requisite for informed conservation planning particularly where the expense and difficulty of deep-sea sampling prohibits comprehensive surveys. This study uses a global database of Antipatharia distribution data to perform habitat suitability modelling using the Maxent methodology to estimate the global extent of black coral habitat suitability. The model of habitat suitability is driven by temperature but there is notable influence from other variables of topography, surface productivity and oxygen levels. This model can be used to predict areas of suitable habitat, which can be useful for conservation planning. The global distribution of Antipatharia habitat suitability shows a marked contrast with the distribution of specimen observations, indicating that many potentially suitable areas have not been sampled, and that sampling effort has been disproportionate to shallow, accessible areas inside marine protected areas (MPAs). Although 25% of Antipatharia observations are located in MPAs, only 7-8% of predicted suitable habitat is protected, which is short of the Convention on Biological Diversity target to protect 10% of ocean habitats by 2020.

  5. Understanding Existing Salmonid Habitat Availability and Connectivity to Improve River Management

    Science.gov (United States)

    Duffin, J.; Yager, E.; Tonina, D.; Benjankar, R. M.

    2017-12-01

    In the Pacific Northwest river restoration is common for salmon conservation. Mangers need methods to help target restoration to problem areas in rivers to create habitat that meets a species' needs. Hydraulic models and habitat suitability curves provide basic information on habitat availability and overall quality, but these analyses need to be expanded to address habitat quality based on the accessibility of habitats required for multiple life stages. Scientists are starting to use connectivity measurements to understand the longitudinal proximity of habitat patches, which can be used to address the habitat variability of a reach. By evaluating the availability and quality of habitat and calculating the connectivity between complementary habitats, such as spawning and rearing habitats, we aim to identify areas that should be targeted for restoration. To meet these goals, we assessed Chinook salmon habitat on the Lemhi River in Idaho. The depth and velocity outputs from a 2D hydraulic model are used in conjunction with locally created habitat suitability curves to evaluate the availability and quality of habitat for multiple Chinook salmon life stages. To assess the variability of the habitat, connectivity between habitat patches necessary for different life stages is calculated with a proximity index. A spatial representation of existing habitat quality and connectivity between complimentary habitats can be linked to river morphology by the evaluation of local geomorphic characteristics, including sinuosity and channel units. The understanding of the current habitat availability for multiple life stage needs, the connectivity between these habitat patches, and their relationship with channel morphology can help managers better identify restoration needs and direct their limited resources.

  6. Sage-grouse habitat selection during winter in Alberta

    Science.gov (United States)

    Carpenter, Jennifer L.; Aldridge, Cameron L.; Boyce, Mark S.

    2010-01-01

    Greater sage-grouse (Centrocercus urophasianus) are dependent on sagebrush (Artemisia spp.) for food and shelter during winter, yet few studies have assessed winter habitat selection, particularly at scales applicable to conservation planning. Small changes to availability of winter habitats have caused drastic reductions in some sage-grouse populations. We modeled winter habitat selection by sage-grouse in Alberta, Canada, by using a resource selection function. Our purpose was to 1) generate a robust winter habitat-selection model for Alberta sage-grouse; 2) spatially depict habitat suitability in a Geographic Information System to identify areas with a high probability of selection and thus, conservation importance; and 3) assess the relative influence of human development, including oil and gas wells, in landscape models of winter habitat selection. Terrain and vegetation characteristics, sagebrush cover, anthropogenic landscape features, and energy development were important in top Akaike's Information Criterionselected models. During winter, sage-grouse selected dense sagebrush cover and homogenous less rugged areas, and avoided energy development and 2-track truck trails. Sage-grouse avoidance of energy development highlights the need for comprehensive management strategies that maintain suitable habitats across all seasons. ?? 2010 The Wildlife Society.

  7. Macrofaunal communities associated with chemosynthetic habitats from the U.S. Atlantic margin: A comparison among depth and habitat types

    Science.gov (United States)

    Bourque, Jill R.; Robertson, Craig M.; Brooke, Sandra; Demopoulos, Amanda W.J.

    2016-01-01

    Hydrocarbon seeps support distinct benthic communities capable of tolerating extreme environmental conditions and utilizing reduced chemical compounds for nutrition. In recent years, several locations of methane seepage have been mapped along the U.S. Atlantic continental slope. In 2012 and 2013, two newly discovered seeps were investigated in this region: a shallow site near Baltimore Canyon (BCS, 366–412 m) and a deep site near Norfolk Canyon (NCS, 1467–1602 m), with both sites containing extensive chemosynthetic mussel bed and microbial mat habitats. Sediment push cores, suction samples, and Ekman box cores were collected to quantify the abundance, diversity, and community structure of benthic macrofauna (>300 μm) in mussel beds, mats, and slope habitats at both sites. Community data from the deep site were also assessed in relation to the associated sediment environment (organic carbon and nitrogen, stable carbon and nitrogen isotopes, grain size, and depth). Infaunal assemblages and densities differed both between depths and among habitat types. Macrofaunal densities in microbial mats were four times greater than those present in mussel beds and slope sediments and were dominated by the annelid families Dorvilleidae, Capitellidae, and Tubificidae, while mussel habitats had higher proportions of crustaceans. Diversity was lower in BCS microbial mat habitats, but higher in mussel and slope sediments compared to NCS habitats. Multivariate statistical analysis revealed specific sediment properties as important for distinguishing the macrofaunal communities, including larger grain sizes present within NCS microbial mat habitats and depleted stable carbon isotopes (δ13C) in sediments present at mussel beds. These results suggest that habitat differences in the quality and source of organic matter are driving the observed patterns in the infaunal assemblages, including high β diversity and high variability in the macrofaunal community composition. This

  8. The energetic consequences of habitat structure for forest stream salmonids.

    Science.gov (United States)

    Naman, Sean M; Rosenfeld, Jordan S; Kiffney, Peter M; Richardson, John S

    2018-05-08

    1.Increasing habitat availability (i.e. habitat suitable for occupancy) is often assumed to elevate the abundance or production of mobile consumers; however, this relationship is often nonlinear (threshold or unimodal). Identifying the mechanisms underlying these nonlinearities is essential for predicting the ecological impacts of habitat change, yet the functional forms and ultimate causation of consumer-habitat relationships are often poorly understood. 2.Nonlinear effects of habitat on animal abundance may manifest through physical constraints on foraging that restrict consumers from accessing their resources. Subsequent spatial incongruence between consumers and resources should lead to unimodal or saturating effects of habitat availability on consumer production if increasing the area of habitat suitable for consumer occupancy comes at the expense of habitats that generate resources. However, the shape of this relationship could be sensitive to cross-ecosystem prey subsidies, which may be unrelated to recipient habitat structure and result in more linear habitat effects on consumer production. 3.We investigated habitat-productivity relationships for juveniles of stream-rearing Pacific salmon and trout (Oncorhynchus spp.), which typically forage in low-velocity pool habitats, while their prey (drifting benthic invertebrates) are produced upstream in high-velocity riffles. However, juvenile salmonids also consume subsidies of terrestrial invertebrates that may be independent of pool-riffle structure. 4.We measured salmonid biomass production in 13 experimental enclosures each containing a downstream pool and upstream riffle, spanning a gradient of relative pool area (14-80% pool). Increasing pool relative to riffle habitat area decreased prey abundance, leading to a nonlinear saturating effect on fish production. We then used bioenergetics model simulations to examine how the relationship between pool area and salmonid biomass is affected by varying levels of

  9. Global screening for Critical Habitat in the terrestrial realm.

    Science.gov (United States)

    Brauneder, Kerstin M; Montes, Chloe; Blyth, Simon; Bennun, Leon; Butchart, Stuart H M; Hoffmann, Michael; Burgess, Neil D; Cuttelod, Annabelle; Jones, Matt I; Kapos, Val; Pilgrim, John; Tolley, Melissa J; Underwood, Emma C; Weatherdon, Lauren V; Brooks, Sharon E

    2018-01-01

    Critical Habitat has become an increasingly important concept used by the finance sector and businesses to identify areas of high biodiversity value. The International Finance Corporation (IFC) defines Critical Habitat in their highly influential Performance Standard 6 (PS6), requiring projects in Critical Habitat to achieve a net gain of biodiversity. Here we present a global screening layer of Critical Habitat in the terrestrial realm, derived from global spatial datasets covering the distributions of 12 biodiversity features aligned with guidance provided by the IFC. Each biodiversity feature is categorised as 'likely' or 'potential' Critical Habitat based on: 1. Alignment between the biodiversity feature and the IFC Critical Habitat definition; and 2. Suitability of the spatial resolution for indicating a feature's presence on the ground. Following the initial screening process, Critical Habitat must then be assessed in-situ by a qualified assessor. This analysis indicates that a total of 10% and 5% of the global terrestrial environment can be considered as likely and potential Critical Habitat, respectively, while the remaining 85% did not overlap with any of the biodiversity features assessed and was classified as 'unknown'. Likely Critical Habitat was determined principally by the occurrence of Key Biodiversity Areas and Protected Areas. Potential Critical Habitat was predominantly characterised by data representing highly threatened and unique ecosystems such as ever-wet tropical forests and tropical dry forests. The areas we identified as likely or potential Critical Habitat are based on the best available global-scale data for the terrestrial realm that is aligned with IFC's Critical Habitat definition. Our results can help businesses screen potential development sites at the early project stage based on a range of biodiversity features. However, the study also demonstrates several important data gaps and highlights the need to incorporate new and

  10. Ground beetle habitat templets and riverbank integrity

    OpenAIRE

    Van Looy, Kris; Vanacker, Stijn; Jochems, Hans; De Blust, Geert; Dufrêne, M

    2006-01-01

    The habitat templet approach was used in a scale-sensitive bioindicator assessment for the ecological integrity of riverbanks and for specific responses to river management. Ground beetle habitat templets were derived from a catchment scale sampling, integrating the overall variety of bank types. This coarse-filter analysis was integrated in the reach scale fine-filtering approaches of community responses to habitat integrity and river management impacts. Higher species diversity was associat...

  11. A Review of Bioeconomic Modelling of Habitat-Fisheries Interactions

    Directory of Open Access Journals (Sweden)

    Naomi S. Foley

    2012-01-01

    Full Text Available This paper reviews the bioeconomic literature on habitat-fisheries connections. Many such connections have been explored in the bioeconomic literature; however, missing from the literature is an analysis merging the potential influences of habitat on both fish stocks and fisheries into one general, overarching theoretical model. We attempt to clarify the nature of linkages between the function of habitats and the economic activities they support. More specifically, we identify theoretically the ways that habitat may enter the standard Gordon-Schaefer model, and nest these interactions in the general model. Habitat influences are defined as either biophysical or bioeconomic. Biophysical effects relate to the functional role of habitat in the growth of the fish stock and may be either essential or facultative to the species. Bioeconomic interactions relate to the effect of habitat on fisheries and can be shown through either the harvest function or the profit function. We review how habitat loss can affect stock, effort, and harvest under open access and maximum economic yield managed fisheries.

  12. Combining information from range use and habitat selection: sex-specific spatial responses to habitat fragmentation in tawny owls Strix aluco

    DEFF Research Database (Denmark)

    Sunde, Peter; Redpath, Stephen M.

    2006-01-01

    than in continuous woods, whereas males utilised farmland woods 3.2 times more intensively. Moreover, females in farmland exploited woodland 3.2 times as intensively as males, apparently because of higher travel costs in open areas. Since the extensive variation in intensity of use as a function...

  13. Bird assemblage patterns in relation to anthropogenic habitat ...

    African Journals Online (AJOL)

    Using habitat stratification, birds were surveyed along transects in tidal and supralittoral sub-habitats using DISTANCE sampling protocol, and along the river by encounter rates to determine abundance and species richness. Indices of human activity as well as habitat structure parameters including ground cover, plant ...

  14. Integrating and interpreting the Habitats- and Birds Directives

    NARCIS (Netherlands)

    Kistenkas, F.H.

    2005-01-01

    The Birds Directive of 1979 and the Habitats Directive of 1992 might be seen as the two major EU nature conservation directives, both protecting a habitats network throughout Europe and species. The transposition of both the Habitats and Birds Directive (HBD) into domestic national or subnational

  15. Adaptive breeding habitat selection: Is it for the birds?

    Science.gov (United States)

    Chalfoun, Anna D.; Schmidt, Kenneth A.

    2012-01-01

    The question of why animals choose particular habitats has important implications for understanding behavioral evolution and distribution of organisms in the wild and for delineating between habitats of different quality for conservation and management. Habitats chosen by animals can influence fitness outcomes via the costs (e.g., predation risk) and benefits (e.g., food availability) of habitat use. Habitat preferences should therefore be under selection to favor those that confer fitness advantages (Clark and Shutler 1999). Indeed, prevailing theory suggests that the habitat preferences of animals should be adaptive, such that fitness is higher in preferred habitats (Hildén 1965, Southwood 1977, Martin 1998). However, studies have often identified apparent mismatches between observed habitat preferences and fitness outcomes across a wide variety of taxa (Valladares and Lawton 1991, Mayhew 1997, Kolbe and Janzen 2002, Arlt and Pärt 2007, Mägi et al. 2009). Certainly, one limitation of studies may be that assessment of “fitness” is typically constrained to fitness surrogates such as nest success rather than lifetime reproductive success or classic Fisherian fitness (Endler 1986). Nevertheless, important habitat choices such as nest sites influence the probability that temporarily sedentary, dependent young are discovered by enemies such as predators and parasites. We therefore expect, on average, to see congruence between evolved habitat preferences and relevant components of fitness (e.g., nest success). Here, we (1) review the prevalence of apparent mismatches between avian breeding-habitat preferences and fitness outcomes using nest-site selection as a focus; (2) describe several potential mechanisms for such mismatches, including anthropogenic, methodological, and ecological–evolutionary; and (3) suggest a framework for understanding the contexts in which habitat preferences represent adaptive decisions, with a primary focus on ecological information

  16. Geomorphology and Sustainable Subsistence Habitats

    Science.gov (United States)

    Johnson, A. C.; Kruger, L. E.

    2016-02-01

    Climatic, tectonic, and human-related impacts are changing the distribution of shoreline habitats and associated species used as food resources. There is a need to summarize current and future shoreline geomorphic - biotic relationships and better understand potential impacts to native customary and traditional gathering patterns. By strategically integrating Native knowledge and observations, we create an inclusive vulnerability assessment strategy resulting in a win-win opportunity for resource users and research scientists alike. We merged the NOAA ShoreZone database with results from over sixty student intern discussions in six southeast Alaska Native communities. Changes in shore width and unit length were derived using near shore bathymetry depths and available isostatic rebound, tectonic movement, and rates of sea level rise. Physical attributes including slope, substrate, and exposure were associated with presence and abundance of specific species. Student interns, selected by Tribes and Tribal associations, conducted resource-based discussions with community members to summarize species use, characteristics of species habitat, transportation used to access collection areas, and potential threats to habitats. Geomorphic trends and community observations were summarized to assess potential threats within a spatial context. Given current measured rates of uplift and sea level rise, 2.4 to 0 m of uplift along with 0.20 m of sea level rise is expected in the next 100 years. Coastlines of southeast Alaska will be subject to both drowning (primarily to the south) and emergence (primarily to the north). We predict decreases in estuary and sediment-dominated shoreline length and an increase in rocky habitats. These geomorphic changes, combined with resident's concerns, highlight six major interrelated coastal vulnerabilities including: (1) reduction of clam and clam habitat quantity and quality, (2) reduction in chiton quality and quantity, (3) harmful expansion of

  17. Ghost of habitat past: historic habitat affects the contemporary distribution of giant garter snakes in a modified landscape.

    Science.gov (United States)

    Halstead, Brian J.; Wylie, Glenn D.; Casazza, Michael L.

    2014-01-01

    Historic habitat conditions can affect contemporary communities and populations, but most studies of historic habitat are based on the reduction in habitat extent or connectivity. Little is known about the effects of historic habitat on contemporary species distributions when historic habitat has been nearly completely removed, but species persist in a highly altered landscape. More than 93% of the historic wetlands in the Central Valley of California, USA, have been drained and converted to agricultural and other uses, but agricultural wetlands, such as rice and its supporting infrastructure of canals, allow some species to persist. Little is known about the distribution of giant garter snakes Thamnophis gigas, a rare aquatic snake species inhabiting this predominantly agricultural landscape, or the variables that affect where this species occurs. We used occupancy modeling to examine the distribution of giant garter snakes at the landscape scale in the Sacramento Valley (northern portion of the Central Valley) of California, with an emphasis on the relative strength of historic and contemporary variables (landscape-scale habitat, local microhabitat, vegetation composition and relative prey counts) for predicting giant garter snake occurrence. Proximity to historic marsh best explained variation in the probability of occurrence of giant garter snakes at the landscape scale, with greater probability of occurrence near historic marsh. We suspect that the importance of distance to historic marsh represents dispersal limitations of giant garter snakes. These results suggest that preserving and restoring areas near historic marsh, and minimizing activities that reduce the extent of marsh or marsh-like (e.g. rice agriculture, canal) habitats near historic marsh may be advantageous to giant garter snakes.

  18. An index of reservoir habitat impairment

    Science.gov (United States)

    Miranda, L.E.; Hunt, K.M.

    2011-01-01

    Fish habitat impairment resulting from natural and anthropogenic watershed and in-lake processes has in many cases reduced the ability of reservoirs to sustain native fish assemblages and fisheries quality. Rehabilitation of impaired reservoirs is hindered by the lack of a method suitable for scoring impairment status. To address this limitation, an index of reservoir habitat impairment (IRHI) was developed by merging 14 metrics descriptive of common impairment sources, with each metric scored from 0 (no impairment) to 5 (high impairment) by fisheries scientists with local knowledge. With a plausible range of 5 to 25, distribution of the IRHI scores ranged from 5 to 23 over 482 randomly selected reservoirs dispersed throughout the USA. The IRHI reflected five impairment factors including siltation, structural habitat, eutrophication, water regime, and aquatic plants. The factors were weakly related to key reservoir characteristics including reservoir area, depth, age, and usetype, suggesting that common reservoir descriptors are poor predictors of fish habitat impairment. The IRHI is rapid and inexpensive to calculate, provides an easily understood measure of the overall habitat impairment, allows comparison of reservoirs and therefore prioritization of restoration activities, and may be used to track restoration progress. The major limitation of the IRHI is its reliance on unstandardized professional judgment rather than standardized empirical measurements. ?? 2010 US Government.

  19. Habitat factors influencing the distribution of Cymbopogon validus in ...

    African Journals Online (AJOL)

    Habitat factors influencing the distribution of Cymbopogon validus in Mkambati Game Reserve, Transkei. ... disturbance; game reserve; grassland; grasslands; habitat conditions; habitat factors; mkambati game ... AJOL African Journals Online.

  20. HABITAT PREFERENSIAL TARSIUS BELITUNG (Cephalopachus bancanus saltator Elliot, 1910

    Directory of Open Access Journals (Sweden)

    Fifin Fitriana

    2017-04-01

    Full Text Available Belitung tarsier (Cephalopachus bancanus saltator is an endemic species in Belitung Island from Cephalopachus genus. Existence of belitung tarsier in its habitat is now under threatened by deforestatition. Due to lack information about its habitat and as conservation effort, this research was tackled to reveal the characteristic of habitat preference of belitung tarsier. The aim of this study are to identify characteristic of habitat preference of belitung tarsier. This research was conducted in March until May 2016 at around Mount Tajam Protected Forest and plantation area. Presence of tarsiers were identified by direct observation, urine odor detection, identifying based tarsier habitat suitability and the local information. Chi-square and Neu methode was used to analyze the variable of habitat preference of belitung tarsiers. This research found that characteristics of habitat preference of belitung tarsier consisted of its homerange was prefer to dry land agricultural and shurb land cover type, not too tight canopy cover (Leaf Area Index /LAI value of 0,83-2,46, close to the edge of forest (0 -874 m, roads (0 – 3.698 m and settlements (0-403 m, elevation range was between 1 -142 m asl, slope slightly (0-15%, temperature 24-25 0C and high rainfall (3.222 – 3.229 mm/year. Characteristic of habitat preference information could be considered to develop conservation action of belitung tarsier. Keywords: belitung tarsiers, habitat, habitat preference, tarsier  

  1. Enhancements of the "eHabitat

    Science.gov (United States)

    Santoro, M.; Dubois, G.; Schulz, M.; Skøien, J. O.; Nativi, S.; Peedell, S.; Boldrini, E.

    2012-04-01

    The number of interoperable research infrastructures has increased significantly with the growing awareness of the efforts made by the Global Earth Observation System of Systems (GEOSS). One of the Social Benefit Areas (SBA) that is benefiting most from GEOSS is biodiversity, given the costs of monitoring the environment and managing complex information, from space observations to species records including their genetic characteristics. But GEOSS goes beyond the simple sharing of the data as it encourages the connectivity of models (the GEOSS Model Web), an approach easing the handling of often complex multi-disciplinary questions such as understanding the impact of environmental and climatological factors on ecosystems and habitats. In the context of GEOSS Architecture Implementation Pilot - Phase 3 (AIP-3), the EC-funded EuroGEOSS and GENESIS projects have developed and successfully demonstrated the "eHabitat" use scenario dealing with Climate Change and Biodiversity domains. Based on the EuroGEOSS multidisciplinary brokering infrastructure and on the DOPA (Digital Observatory for Protected Areas, see http://dopa.jrc.ec.europa.eu/), this scenario demonstrated how a GEOSS-based interoperability infrastructure can aid decision makers to assess and possibly forecast the irreplaceability of a given protected area, an essential indicator for assessing the criticality of threats this protected area is exposed to. The "eHabitat" use scenario was advanced in the GEOSS Sprint to Plenary activity; the advanced scenario will include the "EuroGEOSS Data Access Broker" and a new version of the eHabitat model in order to support the use of uncertain data. The multidisciplinary interoperability infrastructure which is used to demonstrate the "eHabitat" use scenario is composed of the following main components: a) A Discovery Broker: this component is able to discover resources from a plethora of different and heterogeneous geospatial services, presenting them on a single and

  2. Habitat split and the global decline of amphibians.

    Science.gov (United States)

    Becker, Carlos Guilherme; Fonseca, Carlos Roberto; Haddad, Célio Fernando Baptista; Batista, Rômulo Fernandes; Prado, Paulo Inácio

    2007-12-14

    The worldwide decline in amphibians has been attributed to several causes, especially habitat loss and disease. We identified a further factor, namely "habitat split"-defined as human-induced disconnection between habitats used by different life history stages of a species-which forces forest-associated amphibians with aquatic larvae to make risky breeding migrations between suitable aquatic and terrestrial habitats. In the Brazilian Atlantic Forest, we found that habitat split negatively affects the richness of species with aquatic larvae but not the richness of species with terrestrial development (the latter can complete their life cycle inside forest remnants). This mechanism helps to explain why species with aquatic larvae have the highest incidence of population decline. These findings reinforce the need for the conservation and restoration of riparian vegetation.

  3. Steelhead Critical Habitat, Coast - NOAA [ds122

    Data.gov (United States)

    California Department of Resources — This layer depicts areas designated for Steelhead Critical Habitat as well as habitat type and quality in the Coastal California Steelhead ESUs (evolutionarily...

  4. Biodiversidade do solo em ecossistemas brasileiros

    NARCIS (Netherlands)

    Moreira, F.M.S.; Siqueira, J.O.; Brussaard, L.

    2008-01-01

    Biodiversidade do Solo em Ecossistemas Brasileiros R,00 O solo é considerado o ecossistema mais complexo e dinâmico do planeta, cuja heterogeneidade de habitats, que varia na escala de nanômetros até quilômetros, abriga enorme biodiversidade que desempenha papel essencial para a continuida¬de dos

  5. Designated Critical Habitat

    Data.gov (United States)

    Kansas Data Access and Support Center — Critical habitats include those areas documented as currently supporting self-sustaining populations of any threatened or endangered species of wildlife as well as...

  6. Chinook Critical Habitat, Coast - NOAA [ds124

    Data.gov (United States)

    California Department of Resources — This layer depicts areas designated for Chinook Critical Habitat as well as habitat type and quality in the California Coastal Evolutionary Significant Unit (ESU -...

  7. Transient habitats limit development time for periodical cicadas.

    Science.gov (United States)

    Karban, Richard

    2014-01-01

    Periodical cicadas (Magicicada spp.) mature in 13 or 17 years, the longest development times for any non-diapausing insects. Selection may favor prolonged development since nymphs experience little mortality and individuals taking 17 years have been shown to have greater fecundity than those taking 13 years. Why don't periodical cicadas take even longer to develop? Nymphs feed on root xylem fluid and move little. Ovipositing females prefer fast-growing trees at forest edges. I hypothesized that (1) adults emerging at edges would be heavier than those from forest interiors and (2) habitat changes could limit development time. I collected newly eclosed females that had neither fed as adults nor moved from their site of development. For M. septendecim, females from edges were 4.9% heavier than those from the interior. I assumed that emergence density indicated habitat quality and measured density at eight sites in 1979, 1996, and 2013. Over three generations, variation in densities was great; densities at two sites crashed, and at one site they exploded to 579/m2 Habitat transience may limit development time because only adults can reassess habitats and reposition offspring. In conclusion, cicadas are affected by habitat characteristics, habitats change over 17 years, and cicadas may emerge, mate, and redistribute their offspring to track habitat dynamics.

  8. Advantages of a Modular Mars Surface Habitat Approach

    Science.gov (United States)

    Rucker, Michelle A.; Hoffman, Stephan J.; Andrews, Alida; Watts, Kevin

    2018-01-01

    Early crewed Mars mission concepts developed by the National Aeronautics and Space Administration (NASA) assumed a single, large habitat would house six crew members for a 500-day Mars surface stay. At the end of the first mission, all surface equipment, including the habitat, -would be abandoned and the process would be repeated at a different Martian landing site. This work was documented in a series of NASA publications culminating with the Mars Design Reference Mission 5.0 (NASA-SP-2009-566). The Evolvable Mars Campaign (EMC) explored whether re-using surface equipment at a single landing site could be more affordable than the Apollo-style explore-abandon-repeat mission cadence. Initial EMC assumptions preserved the single, monolithic habitat, the only difference being a new requirement to reuse the surface habitat for multiple expedition crews. A trade study comparing a single large habitat versus smaller, modular habitats leaned towards the monolithic approach as more mass-efficient. More recent work has focused on the operational aspects of building up Mars surface infrastructure over multiple missions, and has identified compelling advantages of the modular approach that should be considered before making a final decision. This paper explores Mars surface mission operational concepts and integrated system analysis, and presents an argument for the modular habitat approach.

  9. 50 CFR 660.395 - Essential Fish Habitat (EFH)

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Essential Fish Habitat (EFH) 660.395... Groundfish Fisheries § 660.395 Essential Fish Habitat (EFH) Essential fish habitat (EFH) is defined as those waters and substrate necessary to fish for spawning, breeding, feeding or growth to maturity (16 U.S.C...

  10. Juvenile-adult habitat shift in permian fossil reptiles and amphibians.

    Science.gov (United States)

    Bakker, R T

    1982-07-02

    Among extant large reptiles, juveniles often occupy different habitats from those of adults or subadults and thus avoid competition with and predation from the older animals; small juveniles often choose cryptic habitats because they are vulnerable to a wide variety of predators. Evidence from fossil humeri and femora of Early Permian reptiles collected from sediments of several distinct habitats indicate that similar shifts in habitat occurred. Juvenile Dimetrodon seem to have favored cryptic habitats around swamp and swampy lake margins; adults favored open habitats on the floodplains. Similar patterns of habitat shift seem to be present in the reptile Ophiacodon and the amphibian Eryops and may have been common in fossil tetrapods of the Permian-Triassic.

  11. Managing harvest and habitat as integrated components

    Science.gov (United States)

    Osnas, Erik; Runge, Michael C.; Mattsson, Brady J.; Austin, Jane E.; Boomer, G. S.; Clark, R. G.; Devers, P.; Eadie, J. M.; Lonsdorf, E. V.; Tavernia, Brian G.

    2014-01-01

    In 2007, several important initiatives in the North American waterfowl management community called for an integrated approach to habitat and harvest management. The essence of the call for integration is that harvest and habitat management affect the same resources, yet exist as separate endeavours with very different regulatory contexts. A common modelling framework could help these management streams to better understand their mutual effects. Particularly, how does successful habitat management increase harvest potential? Also, how do regional habitat programmes and large-scale harvest strategies affect continental population sizes (a metric used to express habitat goals)? In the ensuing five years, several projects took on different aspects of these challenges. While all of these projects are still on-going, and are not yet sufficiently developed to produce guidance for management decisions, they have been influential in expanding the dialogue and producing some important emerging lessons. The first lesson has been that one of the more difficult aspects of integration is not the integration across decision contexts, but the integration across spatial and temporal scales. Habitat management occurs at local and regional scales. Harvest management decisions are made at a continental scale. How do these actions, taken at different scales, combine to influence waterfowl population dynamics at all scales? The second lesson has been that consideration of the interface of habitat and harvest management can generate important insights into the objectives underlying the decision context. Often the objectives are very complex and trade-off against one another. The third lesson follows from the second – if an understanding of the fundamental objectives is paramount, there is no escaping the need for a better understanding of human dimensions, specifically the desires of hunters and nonhunters and the role they play in conservation. In the end, the compelling question is

  12. Current practices in the identification of critical habitat for threatened species.

    Science.gov (United States)

    Camaclang, Abbey E; Maron, Martine; Martin, Tara G; Possingham, Hugh P

    2015-04-01

    The term critical habitat is used to describe the subset of habitat that is essential to the survival and recovery of species. Some countries legally require that critical habitat of listed threatened and endangered species be identified and protected. However, there is little evidence to suggest that the identification of critical habitat has had much impact on species recovery. We hypothesized that this may be due at least partly to a mismatch between the intent of critical habitat identification, which is to protect sufficient habitat for species persistence and recovery, and its practice. We used content analysis to systematically review critical habitat documents from the United States, Canada, and Australia. In particular, we identified the major trends in type of information used to identify critical habitat and in occupancy of habitat identified as critical. Information about population viability was used to identify critical habitat for only 1% of the species reviewed, and for most species, designated critical habitat did not include unoccupied habitat. Without reference to population viability, it is difficult to determine how much of a species' occupied and unoccupied habitat will be required for persistence. We therefore conclude that the identification of critical habitat remains inconsistent with the goal of protecting sufficient habitat to support persistence and recovery of the species. Ensuring that critical habitat identification aligns more closely with its intent will improve the accuracy of the designations and may therefore help improve the benefits to species recovery when combined with adequate implementation and enforcement of legal protections. © 2014 Society for Conservation Biology.

  13. Modeling effects of conservation grassland losses on amphibian habitat

    Science.gov (United States)

    Mushet, David M.; Neau, Jordan L.; Euliss, Ned H.

    2014-01-01

    Amphibians provide many ecosystem services valued by society. However, populations have declined globally with most declines linked to habitat change. Wetlands and surrounding terrestrial grasslands form habitat for amphibians in the North American Prairie Pothole Region (PPR). Wetland drainage and grassland conversion have destroyed or degraded much amphibian habitat in the PPR. However, conservation grasslands can provide alternate habitat. In the United States, the Conservation Reserve Program (CRP) is the largest program maintaining grasslands on agricultural lands. We used an ecosystem services model (InVEST) parameterized for the PPR to quantify amphibian habitat over a six-year period (2007–2012). We then quantified changes in availability of amphibian habitat under various land-cover scenarios representing incremental losses (10%, 25%, 50%, 75%, and 100%) of CRP grasslands from 2012 levels. The area of optimal amphibian habitat in the four PPR ecoregions modeled (i.e., Northern Glaciated Plains, Northwestern Glaciated Plains, Lake Agassiz Plain, Des Moines Lobe) declined by approximately 22%, from 3.8 million ha in 2007 to 2.9 million ha in 2012. These losses were driven by the conversion of CRP grasslands to croplands, primarily for corn and soybean production. Our modeling identified an additional 0.8 million ha (26%) of optimal amphibian habitat that would be lost if remaining CRP lands are returned to crop production. An economic climate favoring commodity production over conservation has resulted in substantial losses of amphibian habitat across the PPR that will likely continue into the future. Other regions of the world face similar challenges to maintaining amphibian habitats.

  14. Shallow rocky nursery habitat for fish: Spatial variability of juvenile fishes among this poorly protected essential habitat.

    Science.gov (United States)

    Cheminée, Adrien; Rider, Mary; Lenfant, Philippe; Zawadzki, Audrey; Mercière, Alexandre; Crec'hriou, Romain; Mercader, Manon; Saragoni, Gilles; Neveu, Reda; Ternon, Quentin; Pastor, Jérémy

    2017-06-15

    Coastal nursery habitats are essential for the renewal of adult fish populations. We quantified the availability of a coastal nursery habitat (shallow heterogeneous rocky bottoms) and the spatial variability of its juvenile fish populations along 250km of the Catalan coastline (France and Spain). Nurseries were present in 27% of the coastline, but only 2% of them benefited from strict protection status. For nine taxa characteristic of this habitat, total juvenile densities varied significantly between nursery sites along the coastline, with the highest densities being found on the northern sites. Recruitment level (i.e. a proxy of nursery value) was not explained by protection level, but it was moderately and positively correlated with an anthropization index. Patterns of spatial variations were taxa-specific. Exceptional observations of four juveniles of the protected grouper Epinephelus marginatus were recorded. Our data on habitat availability and recruitment levels provides important informations which help to focus MPA management efforts. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Intercohort density dependence drives brown trout habitat selection

    Science.gov (United States)

    Ayllón, Daniel; Nicola, Graciela G.; Parra, Irene; Elvira, Benigno; Almodóvar, Ana

    2013-01-01

    Habitat selection can be viewed as an emergent property of the quality and availability of habitat but also of the number of individuals and the way they compete for its use. Consequently, habitat selection can change across years due to fluctuating resources or to changes in population numbers. However, habitat selection predictive models often do not account for ecological dynamics, especially density dependent processes. In stage-structured population, the strength of density dependent interactions between individuals of different age classes can exert a profound influence on population trajectories and evolutionary processes. In this study, we aimed to assess the effects of fluctuating densities of both older and younger competing life stages on the habitat selection patterns (described as univariate and multivariate resource selection functions) of young-of-the-year, juvenile and adult brown trout Salmo trutta. We observed all age classes were selective in habitat choice but changed their selection patterns across years consistently with variations in the densities of older but not of younger age classes. Trout of an age increased selectivity for positions highly selected by older individuals when their density decreased, but this pattern did not hold when the density of younger age classes varied. It suggests that younger individuals are dominated by older ones but can expand their range of selected habitats when density of competitors decreases, while older trout do not seem to consider the density of younger individuals when distributing themselves even though they can negatively affect their final performance. Since these results may entail critical implications for conservation and management practices based on habitat selection models, further research should involve a wider range of river typologies and/or longer time frames to fully understand the patterns of and the mechanisms underlying the operation of density dependence on brown trout habitat

  16. Stream Habitat Reach Summary - NCWAP [ds158

    Data.gov (United States)

    California Natural Resource Agency — The Stream Habitat - NCWAP - Reach Summary [ds158] shapefile contains in-stream habitat survey data summarized to the stream reach level. It is a derivative of the...

  17. A Conceptual Approach to Recreation Habitat Analysis

    National Research Council Canada - National Science Library

    Hamilton, H. R

    1996-01-01

    .... The Habitat Evaluation Procedures (HEP) is a commonly used technique for assessing human impacts on the vigor of wildlife species, and serves as the model for the Recreation Habitat Analysis Method (RHAM...

  18. Salmon River Habitat Enhancement, 1989 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Rowe, Mike

    1989-04-01

    This project was funded by the Bonneville Power Administration (BPA). The annual report contains three individual subproject papers detailing tribal fisheries work completed during the summer and fall of 1989. Subproject 1 contains summaries of evaluation/monitoring efforts associated with the Bear Valley Creek, Idaho enhancement project. Subproject 2 contains an evaluation of the Yankee Fork of the Salmon River habitat enhancement project. This report has been sub-divided into two parts: Part 1; stream evaluation and Part 2; pond series evaluation. Subproject 3 concerns the East Fork of the Salmon River, Idaho. This report summarizes the evaluation of the project to date including the 1989 pre-construction evaluation conducted within the East Fork drainage. Dredge mining has degraded spawning and rearing habitat for chinook salmon and steelhead trout in the Yankee Fork drainage of the Salmon River and in Bear Valley Creek. Mining, agricultural, and grazing practices degraded habitat in the East Fork of the Salmon River. Biological monitoring of the success of habitat enhancement for Bear Valley Creek and Yankee Fork are presented in this report. Physical and biological inventories prior to habitat enhancement in East Fork were also conducted. Four series of off-channel ponds of the Yankee Fork are shown to provide effective rearing habitat for chinook salmon. 45 refs., 49 figs., 24 tabs.

  19. Evaluating the habitat capability model for Merriam's turkeys

    Science.gov (United States)

    Mark A. Rumble; Stanley H. Anderson

    1995-01-01

    Habitat capability (HABCAP) models for wildlife assist land managers in predicting the consequences of their management decisions. Models must be tested and refined prior to using them in management planning. We tested the predicted patterns of habitat selection of the R2 HABCAP model using observed patterns of habitats selected by radio-marked Merriam’s turkey (

  20. Influence of habitat degradation on fish replenishment

    Science.gov (United States)

    McCormick, M. I.; Moore, J. A. Y.; Munday, P. L.

    2010-09-01

    Temperature-induced coral bleaching is a major threat to the biodiversity of coral reef ecosystems. While reductions in species diversity and abundance of fish communities have been documented following coral bleaching, the mechanisms that underlie these changes are poorly understood. The present study examined the impacts of coral bleaching on the early life-history processes of coral reef fishes. Daily monitoring of fish settlement patterns found that ten times as many fish settled to healthy coral than sub-lethally bleached coral. Species diversity of settling fishes was least on bleached coral and greatest on dead coral, with healthy coral having intermediate levels of diversity. Laboratory experiments using light-trap caught juveniles showed that different damselfish species chose among healthy, bleached and dead coral habitats using different combinations of visual and olfactory cues. The live coral specialist, Pomacentrus moluccensis, preferred live coral and avoided bleached and dead coral, using mostly visual cues to inform their habitat choice. The habitat generalist, Pomacentrus amboinensis, also preferred live coral and avoided bleached and dead coral but selected these habitats using both visual and olfactory cues. Trials with another habitat generalist, Dischistodus sp., suggested that vision played a significant role. A 20 days field experiment that manipulated densities of P. moluccensis on healthy and bleached coral heads found an influence of fish density on juvenile weight and growth, but no significant influence of habitat quality. These results suggests that coral bleaching will affect settlement patterns and species distributions by influencing the visual and olfactory cues that reef fish larvae use to make settlement choices. Furthermore, increased fish density within the remaining healthy coral habitats could play an important role in influencing population dynamics.

  1. Global patterns of fragmentation and connectivity of mammalian carnivore habitat.

    Science.gov (United States)

    Crooks, Kevin R; Burdett, Christopher L; Theobald, David M; Rondinini, Carlo; Boitani, Luigi

    2011-09-27

    Although mammalian carnivores are vulnerable to habitat fragmentation and require landscape connectivity, their global patterns of fragmentation and connectivity have not been examined. We use recently developed high-resolution habitat suitability models to conduct comparative analyses and to identify global hotspots of fragmentation and connectivity for the world's terrestrial carnivores. Species with less fragmentation (i.e. more interior high-quality habitat) had larger geographical ranges, a greater proportion of habitat within their range, greater habitat connectivity and a lower risk of extinction. Species with higher connectivity (i.e. less habitat isolation) also had a greater proportion of high-quality habitat, but had smaller, not larger, ranges, probably reflecting shorter distances between habitat patches for species with restricted distributions; such species were also more threatened, as would be expected given the negative relationship between range size and extinction risk. Fragmentation and connectivity did not differ among Carnivora families, and body mass was associated with connectivity but not fragmentation. On average, only 54.3 per cent of a species' geographical range comprised high-quality habitat, and more troubling, only 5.2 per cent of the range comprised such habitat within protected areas. Identification of global hotspots of fragmentation and connectivity will help guide strategic priorities for carnivore conservation.

  2. Food Web Response to Habitat Restoration in Various Coastal Wetland Ecosystems

    Science.gov (United States)

    James, W. R.; Nelson, J. A.

    2017-12-01

    Coastal wetland habitats provide important ecosystem services, including supporting coastal food webs. These habitats are being lost rapidly. To combat the effects of these losses, millions of dollars have been invested to restore these habitats. However, the relationship between restoring habitat and restoring ecosystem functioning is poorly understood. Analyzing energy flow through food web comparisons between restored and natural habitats can give insights into ecosystem functioning. Using published stable isotope values from organisms in restored and natural habitats, we assessed the food web response of habitat restoration in salt marsh, mangrove, sea grass, and algal bed ecosystems. We ran Bayesian mixing models to quantify resource use by consumers and generated habitat specific niche hypervolumes for each ecosystem to assess food web differences between restored and natural habitats. Salt marsh, mangrove, and sea grass ecosystems displayed functional differences between restored and natural habitats. Salt marsh and mangrove food webs varied in the amount of each resource used, while the sea grass food web displayed more variation between individual organisms. The algal bed food web showed little variation between restored and natural habitats.

  3. Estuaries and Tidal Marshes. Habitat Pac.

    Science.gov (United States)

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

    This educational packet consists of an overview, three lesson plans, student data sheets, and a poster. The overview examines estuaries and tidal or salt marshes by discussing the plants and animals in these habitats, marsh productivity, benefits and management of the habitats, historical aspects, and development and pollution. A glossary and list…

  4. Loss and modification of habitat: Chapter 1

    Science.gov (United States)

    Lemckert, Francis; Hecnar, Stephen; Pilliod, David S.

    2012-01-01

    Amphibians live in a wide variety of habitats around the world, many of which have been modified or destroyed by human activities. Most species have unique life history characteristics adapted to specific climates, habitats (e.g., lentic, lotic, terrestrial, arboreal, fossorial, amphibious), and local conditions that provide suitable areas for reproduction, development and growth, shelter from environmental extremes, and predation, as well as connectivity to other populations or habitats. Although some species are entirely aquatic or terrestrial, most amphibians, as their name implies, lead a dual life and require a mosaic of habitats in both aquatic and terrestrial ecosystems. With over 6 billion people on Earth, most species are now persisting in habitats that have been directly or indirectly influenced by human activities. Some species have disappeared where their habitats have been completely destroyed, reduced, or rendered unsuitable. Habitat loss and degradation are widely considered by most researchers as the most important causes of amphibian population decline globally (Barinaga 1990; Wake and Morowitz 1991; Alford and Richards 1999). In this chapter, a background on the diverse habitat requirements of amphibians is provided, followed by a discussion of the effects of urbanization, agriculture, livestock grazing, timber production and harvesting, fire and hazardous fuel management, and roads on amphibians and their habitats. Also briefly discussed is the influence on amphibian habitats of natural disturbances, such as extreme weather events and climate change, given the potential for human activities to impact climate in the longer term. For amphibians in general, microhabitats are of greater importance than for other vertebrates. As ectotherms with a skin that is permeable to water and with naked gelatinous eggs, amphibians are physiologically constrained to be active during environmental conditions that provide appropriate body temperatures and adequate

  5. Fibromyalgia patients' quality of life and pain intensity variation Variação da intensidade da dor e da qualidade de vida de pacientes com fibromialgia

    Directory of Open Access Journals (Sweden)

    José Eduardo Martinez

    2008-12-01

    Full Text Available INTRODUCTION: One of the most reported issues on the Fibromyalgia syndrome is the pain intensity variation and its impact on patients' life quality. OBJECTIVES: 1 to establish the correlation among pain, anxiety and depression intensity perception; 2 to determine whether there is a correlation between pain intensity variation and the impact of fibromyalgia on patients' quality of life. MATERIAL AND METHODS: A study was carried out with 21 patients, who received a diary to register their perceptions on pain, anxiety and depression intensity. The patients have made this procedure three times a day, for a fifteen-day period. The impact on life quality was measured by the the Fibromyalgia Impact Questionaire (FIQ. RESULTS: It was observed a significant variation on pain intensity during the day periods. There was not a significant variation for anxiety and depression through the day periods. It was not observed any significant correlation between pain and depression or pain and anxiety intensity perception at any time of the day, during the study period. When considering the whole study period, it was observed that there was a correlation between pain and anxiety and pain and depression in the morning. CONCLUSION: It is concluded that there is a significant pain variation through the day periods and there is a correlation between pain and anxiety and pain and depression in the morning. There is a significant correlation of life quality with pain in the morning, anxiety in the afternoon and evening; and depression in all periods of the day.INTRODUÇÃO: Uma das questões mais relatadas é a variação da intensidade da dor no decorrer do dia e seu impacto na qualidade de vida. OBJETIVOS: Estabelecer a correlação entre a percepção da intensidade da dor, da ansiedade e da depressão e determinar a correlação entre a variação da intensidade da dor e o impacto na qualidade de vida. MATERIAL E MÉTODOS: Estudou-se 21 pacientes com fibromialgia. As

  6. Complementary habitat use by wild bees in agro-natural landscapes.

    Science.gov (United States)

    Mandelik, Yael; Winfree, Rachael; Neeson, Thomas; Kremen, Claire

    2012-07-01

    Human activity causes abrupt changes in resource availability across the landscape. In order to persist in human-altered landscapes organisms need to shift their habitat use accordingly. Little is known about the mechanisms by which whole communities persist in human-altered landscapes, including the role of complementary habitat use. We define complementary habitat use as the use of different habitats at different times by the same group of species during the course of their activity period. We hypothesize that complementary habitat use is a mechanism through which native bee species persist in human-altered landscapes. To test this idea, we studied wild bee communities in agro-natural landscapes and explored their community-level patterns of habitat and resource use over space and time. The study was conducted in six agro-natural landscapes in the eastern United States, each containing three main bee habitat types (natural habitat, agricultural fields, and old fields). Each of the three habitats exhibited a unique seasonal pattern in amount, diversity, and composition of floral resources, and together they created phenological complementarity in foraging resources for bees. Individual bee species as well as the bee community responded to these spatiotemporal patterns in floral availability and exhibited a parallel pattern of complementary habitat use. The majority of wild bee species, including all the main crop visitors, used fallow areas within crops early in the season, shifted to crops in mid-season, and used old-field habitats later in the season. The natural-forest habitat supported very limited number of bees, mostly visitors of non-crop plants. Old fields are thus an important feature in these arable landscapes for maintaining crop pollination services. Our study provides a detailed examination of how shifts in habitat and resource use may enable bees to persist in highly dynamic agro-natural landscapes, and points to the need for a broad cross-habitat

  7. GIS habitat analysis for lesser prairie-chickens in southeastern New Mexico

    Directory of Open Access Journals (Sweden)

    Neville Paul

    2006-12-01

    Full Text Available Abstract Background We conducted Geographic Information System (GIS habitat analyses for lesser prairie-chicken (LPCH, Tympanuchus pallidicinctus conservation planning. The 876,799 ha study area included most of the occupied habitat for the LPCH in New Mexico. The objectives were to identify and quantify: 1. suitable LPCH habitat in New Mexico, 2. conversion of native habitats, 3. potential for habitat restoration, and 4. unsuitable habitat available for oil and gas activities. Results We found 16% of suitable habitat (6% of the study area distributed in 13 patches of at least 3,200 ha and 11% of suitable habitat (4% of the study area distributed in four patches over 7,238 ha. The area converted from native vegetation types comprised 17% of the study area. Ninety-five percent of agricultural conversion occurred on private lands in the northeastern corner of the study area. Most known herbicide-related conversions (82% occurred in rangelands in the western part of the study area, on lands managed primarily by the US Bureau of Land Management (BLM. We identified 88,190 ha (10% of the study area of habitats with reasonable restoration potential. Sixty-two percent of the primary population area (PPA contained occupied, suitable, or potentially suitable habitat, leaving 38% that could be considered for oil and gas development. Conclusion Although suitable LPCH habitat appears at first glance to be abundant in southeastern New Mexico, only a fraction of apparently suitable vegetation types constitute quality habitat. However, we identified habitat patches that could be restored through mesquite control or shin-oak reintroduction. The analysis also identified areas of unsuitable habitat with low restoration potential that could be targeted for oil and gas exploration, in lieu of occupied, high-quality habitats. Used in combination with GIS analysis and current LPCH population data, the habitat map represents a powerful conservation and management tool.

  8. GIS habitat analysis for lesser prairie-chickens in southeastern New Mexico.

    Science.gov (United States)

    Johnson, Kristine; Neville, Teri B; Neville, Paul

    2006-12-04

    We conducted Geographic Information System (GIS) habitat analyses for lesser prairie-chicken (LPCH, Tympanuchus pallidicinctus) conservation planning. The 876,799 ha study area included most of the occupied habitat for the LPCH in New Mexico. The objectives were to identify and quantify: 1. suitable LPCH habitat in New Mexico, 2. conversion of native habitats, 3. potential for habitat restoration, and 4. unsuitable habitat available for oil and gas activities. We found 16% of suitable habitat (6% of the study area) distributed in 13 patches of at least 3,200 ha and 11% of suitable habitat (4% of the study area) distributed in four patches over 7,238 ha. The area converted from native vegetation types comprised 17% of the study area. Ninety-five percent of agricultural conversion occurred on private lands in the northeastern corner of the study area. Most known herbicide-related conversions (82%) occurred in rangelands in the western part of the study area, on lands managed primarily by the US Bureau of Land Management (BLM). We identified 88,190 ha (10% of the study area) of habitats with reasonable restoration potential. Sixty-two percent of the primary population area (PPA) contained occupied, suitable, or potentially suitable habitat, leaving 38% that could be considered for oil and gas development. Although suitable LPCH habitat appears at first glance to be abundant in southeastern New Mexico, only a fraction of apparently suitable vegetation types constitute quality habitat. However, we identified habitat patches that could be restored through mesquite control or shin-oak reintroduction. The analysis also identified areas of unsuitable habitat with low restoration potential that could be targeted for oil and gas exploration, in lieu of occupied, high-quality habitats. Used in combination with GIS analysis and current LPCH population data, the habitat map represents a powerful conservation and management tool.

  9. Physical habitat simulation system reference manual: version II

    Science.gov (United States)

    Milhous, Robert T.; Updike, Marlys A.; Schneider, Diane M.

    1989-01-01

    There are four major components of a stream system that determine the productivity of the fishery (Karr and Dudley 1978). These are: (1) flow regime, (2) physical habitat structure (channel form, substrate distribution, and riparian vegetation), (3) water quality (including temperature), and (4) energy inputs from the watershed (sediments, nutrients, and organic matter). The complex interaction of these components determines the primary production, secondary production, and fish population of the stream reach. The basic components and interactions needed to simulate fish populations as a function of management alternatives are illustrated in Figure I.1. The assessment process utilizes a hierarchical and modular approach combined with computer simulation techniques. The modular components represent the "building blocks" for the simulation. The quality of the physical habitat is a function of flow and, therefore, varies in quality and quantity over the range of the flow regime. The conceptual framework of the Incremental Methodology and guidelines for its application are described in "A Guide to Stream Habitat Analysis Using the Instream Flow Incremental Methodology" (Bovee 1982). Simulation of physical habitat is accomplished using the physical structure of the stream and streamflow. The modification of physical habitat by temperature and water quality is analyzed separately from physical habitat simulation. Temperature in a stream varies with the seasons, local meteorological conditions, stream network configuration, and the flow regime; thus, the temperature influences on habitat must be analysed on a stream system basis. Water quality under natural conditions is strongly influenced by climate and the geological materials, with the result that there is considerable natural variation in water quality. When we add the activities of man, the possible range of water quality possibilities becomes rather large. Consequently, water quality must also be analysed on a

  10. Comparison of two methods for estimating the abundance, diversity and habitat preference of fluvial macroinvertebrates in contrasting habitats

    NARCIS (Netherlands)

    Alonso, A.; Camargo, J.A.

    2010-01-01

    In this research we evaluate the effects of the method used for estimating the potential surface available for benthic macroinvertebrates in macrophyte and unvegetated habitats on several metrics and habitat preference of aquatic macroinvertebrates in the upper catchment of the Henares River

  11. Habitat Evaluation Procedures (HEP) Report; Gamblin Lake, Technical Report 2005.

    Energy Technology Data Exchange (ETDEWEB)

    Entz, Ray

    2005-05-01

    On August 12, 2003, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the Gamblin Lake property, an acquisition completed by the Kalispel Tribe of Indians in December 2002. Evaluation species and appropriate models include bald eagle, black-capped chickadee, mallard, muskrat, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The Gamblin Lake Project provides a total of 273.28 Habitat Units (HUs) for the species evaluated. Conifer forest habitat provides 127.92 HUs for bald eagle, black-capped chickadee, mallard, and white-tailed deer. Forested wetland habitat provides 21.06 HUs for bald eagle, black-caped chickadee, mallard, and white-tailed deer. Wet meadow provides 78.05 HUs for Canada goose and mallard. Emergent wetland habitat provides 46.25 HUs for mallard, muskrat, and Canada goose. The objective of using HEP at the Gamblin Lake Project and other protected properties is to document the quality and quantity of available habitat for selected wildlife species. In this way, HEP provides information on the relative value of the same area at future points in time so that the effect of management activities on wildlife habitat can be quantified. When combined with other tools, the baseline HEP will be used to determine the most effective on-site management, restoration, and enhancement actions to increase habitat suitability for targeted species. The same process will be replicated every five years to quantitatively evaluate the effectiveness of management strategies in improving and maintaining habitat conditions while providing additional crediting to BPA for enhanced habitat values.

  12. A test of the habitat suitability model for Merriam's wild turkeys

    Science.gov (United States)

    Mark A. Rumble; Stanley H. Anderson

    1996-01-01

    An important research area regarding the wild turkey (Meleagris gallopavo) is development of sound habitat models. Habitat models provide standardized methods to quantify wild turkey habitat and stimulate new research hypotheses. Habitat suitability index (HSI) models show species-habitat relationships on a scale of O-l, with 1 being optimum. A...

  13. GIS habitat analysis for lesser prairie-chickens in southeastern New Mexico

    OpenAIRE

    Johnson, Kristine; Neville, Teri B; Neville, Paul

    2006-01-01

    Abstract Background We conducted Geographic Information System (GIS) habitat analyses for lesser prairie-chicken (LPCH, Tympanuchus pallidicinctus) conservation planning. The 876,799 ha study area included most of the occupied habitat for the LPCH in New Mexico. The objectives were to identify and quantify: 1. suitable LPCH habitat in New Mexico, 2. conversion of native habitats, 3. potential for habitat restoration, and 4. unsuitable habitat available for oil and gas activities. Results We f...

  14. Habitat Fragmentation and Native Bees: a Premature Verdict?

    Directory of Open Access Journals (Sweden)

    James H. Cane

    2001-06-01

    Full Text Available Few studies directly address the consequences of habitat fragmentation for communities of pollinating insects, particularly for the key pollinator group, bees (Hymenoptera: Apiformes. Bees typically live in habitats where nesting substrates and bloom are patchily distributed and spatially dissociated. Bee studies have all defined habitat fragments as remnant patches of floral hosts or forests, overlooking the nesting needs of bees. Several authors conclude that habitat fragmentation is broadly deleterious, but their own data show that some native species proliferate in sampled fragments. Other studies report greater densities and comparable diversities of native bees at flowers in some fragment size classes relative to undisrupted habitats, but find dramatic shifts in species composition. Insightful studies of habitat fragmentation and bees will consider fragmentation, alteration, and loss of nesting habitats, not just patches of forage plants, as well as the permeability of the surrounding matrix to interpatch movement. Inasmuch as the floral associations and nesting habits of bees are often attributes of species or subgenera, ecological interpretations hinge on authoritative identifications. Study designs must accommodate statistical problems associated with bee community samples, especially non-normal data and frequent zero values. The spatial scale of fragmentation must be appreciated: bees of medium body size can regularly fly 1-2 km from nest site to forage patch. Overall, evidence for prolonged persistence of substantial diversity and abundances of native bee communities in habitat fragments of modest size promises practical solutions for maintaining bee populations. Provided that reserve selection, design, and management can address the foraging and nesting needs of bees, networks of even small reserves may hold hope for sustaining considerable pollinator diversity and the ecological services pollinators provide.

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

    Science.gov (United States)

    Igl, Lawrence D.; Ballard, Bart M.

    1999-01-01

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

  16. Chamaedorea: diverse species in diverse habitats

    Directory of Open Access Journals (Sweden)

    1992-01-01

    Full Text Available DIVERSES ESPÈCES DANS DIVERS HABITATS. Des espèces extraordinairement diverses se trouvant dans des habitats également divers caractérisent Chamaedorea, un genre qui compte environ 90 espèces dioïques limitées aux sous-bois des forêts néo-tropicales constamment dans la pluie et les nuages du Mexique à la Bolivie et à l’Équateur. Une vaste gamme de formes biologiques, de tiges, de feuilles, d’inflorescences, de fleurs, et de fruits reflète la diversité des espèces. Bien que le genre soit plus riche en espèces dans les forêts denses et humides situées entre 800-1,500 mètres d’altitude, quelques espèces exceptionnelles se trouvent dans des forêts moins denses et/ou occasionnellement sèches, sur des substances dures ou dans d’autres habitats inhabituels. DIVERSAS ESPECIES EN DIVERSOS HÁBITATS. Especies notablemente diversas presentes en habitats igualmente diversos caracterizan a Chamaedorea, un genero de aproximadamente 90 especies dioicas limitadas al sotobosque de los bosques lluviosos y nubosos neotropicales desde Mexico hasta Bolivia y Ecuador. Una amplia gama de formas biológicas, tallos, hojas, inflorescencias, flores, y frutos refleja la diversidad de las especies. Aunque el género es más rico en especies en los bosques densos y húmedos de 800-1,500 metros de altura, unas pocas especies excepcionales ocurren en bosques abiertos o ocasionalmente secos, en substrato severo o en otros habitats extraordinarios. Remarkably diverse species occurring in equally diverse habitats characterize Chamaedorea, a genus of about 90, dioecious species restricted to the understory of neotropical rain and cloud forests from Mexico to Bolivia and Ecuador. A vast array of habits, stems, leaves, inflorescences, flowers, and fruits reflect the diversity of species. Although the genus is most species-rich in dense, moist or wet, diverse forests from 800-1,500 meters elevation, a few exceptional species occur in open and/or seasonally

  17. Specializing on vulnerable habitat: Acropora selectivity among damselfish recruits and the risk of bleaching-induced habitat loss

    Science.gov (United States)

    Bonin, M. C.

    2012-03-01

    Coral reef habitats are increasingly being degraded and destroyed by a range of disturbances, most notably climate-induced coral bleaching. Habitat specialists, particularly those associated with susceptible coral species, are clearly among the most vulnerable to population decline or extinction. However, the degree of specialization on coral microhabitats is still unclear for one of the most ubiquitous, abundant and well studied of coral reef fish families—the damselfishes (Pomacentridae). Using high taxonomic resolution surveys of microhabitat use and availability, this study provides the first species-level description of patterns of Acropora selectivity among recruits of 10 damselfish species in order to determine their vulnerability to habitat degradation. In addition, surveys of the bleaching susceptibility of 16 branching coral species revealed which preferred recruitment microhabitats are at highest risk of decline as a result of chronic coral bleaching. Four species (i.e., Chrysiptera parasema, Pomacentrus moluccensis, Dascyllus melanurus and Chromis retrofasciata) were identified as highly vulnerable because they used only branching hard corals as recruitment habitat and primarily associated with only 2-4 coral species. The bleaching surveys revealed that five species of Acropora were highly susceptible to bleaching, with more than 50% of colonies either severely bleached or already dead. These highly susceptible corals included two of the preferred microhabitats of the specialist C. parasema and represented a significant proportion of its total recruitment microhabitat. In contrast, highly susceptible corals were rarely used by another specialist, P. moluccensis, suggesting that this species faces a lower risk of bleaching-induced habitat loss compared to C. parasema. As degradation to coral reef habitats continues, specialists will increasingly be forced to use alternative recruitment microhabitats, and this is likely to reduce population

  18. Modeling Impacts of Climate Change on Giant Panda Habitat

    Directory of Open Access Journals (Sweden)

    Melissa Songer

    2012-01-01

    Full Text Available Giant pandas (Ailuropoda melanoleuca are one of the most widely recognized endangered species globally. Habitat loss and fragmentation are the main threats, and climate change could significantly impact giant panda survival. We integrated giant panda habitat information with general climate models (GCMs to predict future geographic distribution and fragmentation of giant panda habitat. Results support a major general prediction of climate change—a shift of habitats towards higher elevation and higher latitudes. Our models predict climate change could reduce giant panda habitat by nearly 60% over 70 years. New areas may become suitable outside the current geographic range but much of these areas is far from the current giant panda range and only 15% fall within the current protected area system. Long-term survival of giant pandas will require the creation of new protected areas that are likely to support suitable habitat even if the climate changes.

  19. Microhabitat features influencing habitat use by Florida black bears

    Directory of Open Access Journals (Sweden)

    Dana L. Karelus

    2018-01-01

    Full Text Available Understanding fine-scale habitat needs of species and the factors influencing heterogeneous use of habitat within home range would help identify limiting resources and inform habitat management practices. This information is especially important for large mammals living in fragmented habitats where resources may be scarcer and more patchily distributed than in contiguous habitats. Using bihourly Global Position System (GPS location data collected from 10 individuals during 2011–2014, we investigated microhabitat features of areas within home ranges that received high vs. low intensity of use by Florida black bears (Ursus americanus floridanus in north-central, Florida. We identified areas receiving high and low levels of use by bears based on their utilization distributions estimated with the dynamic Brownian bridge movement model, and performed vegetation sampling at bear locations within high- and low-use areas. Using univariate analyses and generalized linear mixed models, we found that (1 canopy cover, visual obstruction, and hardwood density were important in defining high-use sites; (2 the probability of high use was positively associated with principal components that represented habitat closer to creeks and with high canopy and shrub cover and higher hardwood densities, likely characteristic of forested wetlands; and (3 the probability of high use was, to a lesser extent, associated with principal components that represented habitat with high canopy cover, high pine density, and low visual obstruction and hardwood density; likely representing sand pine and pine plantations. Our results indicate that the high bear-use sites were in forested wetlands, where cover and food resources for bears are likely to occur in higher abundance. Habitat management plans whereby bears are a focal species should aim to increase the availability and quality of forested wetlands. Keywords: Habitat selection, Heterogeneous habitat use, Forest management

  20. Assessing habitat connectivity for ground-dwelling animals in an urban environment.

    Science.gov (United States)

    Braaker, S; Moretti, M; Boesch, R; Ghazoul, J; Obrist, M K; Bontadina, F

    To ensure viable species populations in fragmented landscapes, individuals must be able to move between suitable habitat patches. Despite the increased interest in biodiversity assessment in urban environments, the ecological relevance of habitat connectivity in highly fragmented landscapes remains largely unknown. The first step to understanding the role of habitat connectivity in urban ecology is the challenging task of assessing connectivity in the complex patchwork of contrasting habitats that is found in cities. We developed a data-based framework, minimizing the use of subjective assumptions, to assess habitat connectivity that consists of the following sequential steps: (1) identification of habitat preference based on empirical habitat-use data; (2) derivation of habitat resistance surfaces evaluating various transformation functions; (3) modeling of different connectivity maps with electrical circuit theory (Circuitscape), a method considering all possible pathways across the landscape simultaneously; and (4) identification of the best connectivity map with information-theoretic model selection. We applied this analytical framework to assess habitat connectivity for the European hedgehog Erinaceus europaeus, a model species for ground-dwelling animals, in the city of Zurich, Switzerland, using GPS track points from 40 individuals. The best model revealed spatially explicit connectivity “pinch points,” as well as multiple habitat connections. Cross-validation indicated the general validity of the selected connectivity model. The results show that both habitat connectivity and habitat quality affect the movement of urban hedgehogs (relative importance of the two variables was 19.2% and 80.8%, respectively), and are thus both relevant for predicting urban animal movements. Our study demonstrates that even in the complex habitat patchwork of cities, habitat connectivity plays a major role for ground-dwelling animal movement. Data-based habitat connectivity

  1. Estudos sôbre reservatórios e vectores silvestres do Trypanosoma cruzi. XXIV. Variação dos dados biométricos obtidos em amostras do T. cruzi isolados de casos humanos da Doença de Chagas

    Directory of Open Access Journals (Sweden)

    Francisco Ferriolli Filho

    1968-02-01

    Full Text Available Estudo biométrico de 10 amostras de Trypanosoma cruzi isoladas de casos humanos da doença de CHAGAS, nove mantidas em camundongos brancos jovens e uma mantida em ratos brancos jovens, mostrou a existência de grandes variações amostrais. Assim os valores do comprimento total médio das diferentes amostras variaram entre 16,3μ e 21,8μ., enquanto os valores do índice nuclear médio oscilaram entre 0,93 e 1,52. Êstes resultados ampliam os limites de variações amostrais até agora observadas no T. cruzi, especialmente os que se referem ao índice nuclear médio.

  2. Desert tortoise use of burned habitat in the Eastern Mojave desert

    Science.gov (United States)

    Drake, Karla K.; Esque, Todd C.; Nussear, Kenneth E.; DeFalco, Lesley; Scoles, Sara; Modlin, Andrew T.; Medica, Philip A.

    2015-01-01

    Wildfires burned 24,254 ha of critical habitat designated for the recovery of the threatened Mojave desert tortoise (Gopherus agassizii) in southern Nevada during 2005. The proliferation of non-native annual grasses has increased wildfire frequency and extent in recent decades and continues to accelerate the conversion of tortoise habitat across the Mojave Desert. Immediate changes to vegetation are expected to reduce quality of critical habitat, yet whether tortoises will use burned and recovering habitat differently from intact unburned habitat is unknown. We compared movement patterns, home-range size, behavior, microhabitat use, reproduction, and survival for adult desert tortoises located in, and adjacent to, burned habitat to understand how tortoises respond to recovering burned habitat. Approximately 45% of home ranges in the post-fire environment contained burned habitat, and numerous observations (n = 12,223) corroborated tortoise use of both habitat types (52% unburned, 48% burned). Tortoises moved progressively deeper into burned habitat during the first 5 years following the fire, frequently foraging in burned habitats that had abundant annual plants, and returning to adjacent unburned habitat for cover provided by intact perennial vegetation. However, by years 6 and 7, the live cover of the short-lived herbaceous perennial desert globemallow (Sphaeralcea ambigua) that typically re-colonizes burned areas declined, resulting in a contraction of tortoise movements from the burned areas. Health and egg production were similar between burned and unburned areas indicating that tortoises were able to acquire necessary resources using both areas. This study documents that adult Mojave desert tortoises continue to use habitat burned once by wildfire. Thus, continued management of this burned habitat may contribute toward the recovery of the species in the face of many sources of habitat loss.

  3. Beyond habitat structure: Landscape heterogeneity explains the monito del monte (Dromiciops gliroides) occurrence and behavior at habitats dominated by exotic trees.

    Science.gov (United States)

    Salazar, Daniela A; Fontúrbel, Francisco E

    2016-09-01

    Habitat structure determines species occurrence and behavior. However, human activities are altering natural habitat structure, potentially hampering native species due to the loss of nesting cavities, shelter or movement pathways. The South American temperate rainforest is experiencing an accelerated loss and degradation, compromising the persistence of many native species, and particularly of the monito del monte (Dromiciops gliroides Thomas, 1894), an arboreal marsupial that plays a key role as seed disperser. Aiming to compare 2 contrasting habitats (a native forest and a transformed habitat composed of abandoned Eucalyptus plantations and native understory vegetation), we assessed D. gliroides' occurrence using camera traps and measured several structural features (e.g. shrub and bamboo cover, deadwood presence, moss abundance) at 100 camera locations. Complementarily, we used radio telemetry to assess its spatial ecology, aiming to depict a more complete scenario. Moss abundance was the only significant variable explaining D. gliroides occurrence between habitats, and no structural variable explained its occurrence at the transformed habitat. There were no differences in home range, core area or inter-individual overlapping. In the transformed habitats, tracked individuals used native and Eucalyptus-associated vegetation types according to their abundance. Diurnal locations (and, hence, nesting sites) were located exclusively in native vegetation. The landscape heterogeneity resulting from the vicinity of native and Eucalyptus-associated vegetation likely explains D. gliroides occurrence better than the habitat structure itself, as it may be use Eucalyptus-associated vegetation for feeding purposes but depend on native vegetation for nesting. © 2016 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

  4. Lowland tapir distribution and habitat loss in South America

    Directory of Open Access Journals (Sweden)

    Jose Luis Passos Cordeiro

    2016-09-01

    Full Text Available The development of species distribution models (SDMs can help conservation efforts by generating potential distributions and identifying areas of high environmental suitability for protection. Our study presents a distribution and habitat map for lowland tapir in South America. We also describe the potential habitat suitability of various geographical regions and habitat loss, inside and outside of protected areas network. Two different SDM approaches, MAXENT and ENFA, produced relative different Habitat Suitability Maps for the lowland tapir. While MAXENT was efficient at identifying areas as suitable or unsuitable, it was less efficient (when compared to the results by ENFA at identifying the gradient of habitat suitability. MAXENT is a more multifaceted technique that establishes more complex relationships between dependent and independent variables. Our results demonstrate that for at least one species, the lowland tapir, the use of a simple consensual approach (average of ENFA and MAXENT models outputs better reflected its current distribution patterns. The Brazilian ecoregions have the highest habitat loss for the tapir. Cerrado and Atlantic Forest account for nearly half (48.19% of the total area lost. The Amazon region contains the largest area under protection, and the most extensive remaining habitat for the tapir, but also showed high levels of habitat loss outside protected areas, which increases the importance of support for proper management.

  5. Lowland tapir distribution and habitat loss in South America.

    Science.gov (United States)

    Cordeiro, Jose Luis Passos; Fragoso, José M V; Crawshaw, Danielle; Oliveira, Luiz Flamarion B

    2016-01-01

    The development of species distribution models (SDMs) can help conservation efforts by generating potential distributions and identifying areas of high environmental suitability for protection. Our study presents a distribution and habitat map for lowland tapir in South America. We also describe the potential habitat suitability of various geographical regions and habitat loss, inside and outside of protected areas network. Two different SDM approaches, MAXENT and ENFA, produced relative different Habitat Suitability Maps for the lowland tapir. While MAXENT was efficient at identifying areas as suitable or unsuitable, it was less efficient (when compared to the results by ENFA) at identifying the gradient of habitat suitability. MAXENT is a more multifaceted technique that establishes more complex relationships between dependent and independent variables. Our results demonstrate that for at least one species, the lowland tapir, the use of a simple consensual approach (average of ENFA and MAXENT models outputs) better reflected its current distribution patterns. The Brazilian ecoregions have the highest habitat loss for the tapir. Cerrado and Atlantic Forest account for nearly half (48.19%) of the total area lost. The Amazon region contains the largest area under protection, and the most extensive remaining habitat for the tapir, but also showed high levels of habitat loss outside protected areas, which increases the importance of support for proper management.

  6. Habitat Evaluation Procedures (HEP) Report; Beaver Lake, Technical Report 2005.

    Energy Technology Data Exchange (ETDEWEB)

    Entz, Ray

    2005-05-01

    On August 14, 2003, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the Beaver Lake property, an acquisition completed by the Kalispel Tribe of Indians in November 2002. Evaluation species and appropriate models include bald eagle, black-capped chickadee, Canada goose, mallard, muskrat, yellow warbler, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The Beaver Lake Project provides a total of 232.26 Habitat Units (HUs) for the species evaluated. Conifer forest habitat provides 136.58 HUs for bald eagle, black-capped chickadee, mallard, and white-tailed deer. Forested wetland habitat provides 20.02 HUs for bald eagle, black-caped chickadee, mallard, and white-tailed deer. Scrub-shrub wetland habitat provides 7.67 HUs for mallard, yellow warbler, and white-tailed deer. Grassland meadow provides 22.69 HUs for Canada goose and mallard. Emergent wetlands provide 35.04 HUs for Canada goose, mallard, and muskrat. Open water provided 10.26 HUs for Canada goose, mallard, and muskrat. The objective of using HEP at the Beaver Lake Project and other protected properties is to document the quality and quantity of available habitat for selected wildlife species. In this way, HEP provides information on the relative value of the same area at future points in time so that the effect of management activities on wildlife habitat can be quantified. When combined with other tools, the baseline HEP will be used to determine the most effective on-site management, restoration, and enhancement actions to increase habitat suitability for targeted species. The same process will be replicated every five years to quantitatively evaluate the effectiveness of management strategies in improving and maintaining habitat conditions while providing additional crediting to BPA for enhanced habitat values.

  7. CTUIR Umatilla Anadromous Fisheries Habitat Project : A Columbia River Basin Fish Habitat Project 2008 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Hoverson, Eric D.; Amonette, Alexandra

    2009-02-09

    The Umatilla Anadromous Fisheries Habitat Project (UAFHP) is an ongoing effort to protect, enhance, and restore riparian and instream habitat for the natural production of anadromous salmonids in the Umatilla River Basin, Northeast Oregon. Flow quantity, water temperature, passage, and lack of in-stream channel complexity have been identified as the key limiting factors in the basin. During the 2008 Fiscal Year (FY) reporting period (February 1, 2008-January 31, 2009) primary project activities focused on improving instream and riparian habitat complexity, migrational passage, and restoring natural channel morphology and floodplain function. Eight primary fisheries habitat enhancement projects were implemented on Meacham Creek, Birch Creek, West Birch Creek, McKay Creek, West Fork Spring Hollow, and the Umatilla River. Specific restoration actions included: (1) rectifying one fish passage barrier on West Birch Creek; (2) participating in six projects planting 10,000 trees and seeding 3225 pounds of native grasses; (3) donating 1000 ft of fencing and 1208 fence posts and associated hardware for 3.6 miles of livestock exclusion fencing projects in riparian areas of West Birch and Meacham Creek, and for tree screens to protect against beaver damage on West Fork Spring Hollow Creek; (4) using biological control (insects) to reduce noxious weeds on three treatment areas covering five acres on Meacham Creek; (5) planning activities for a levee setback project on Meacham Creek. We participated in additional secondary projects as opportunities arose. Baseline and ongoing monitoring and evaluation activities were also completed on major project areas such as conducting photo point monitoring strategies activities at the Meacham Creek Large Wood Implementation Project site (FY2006) and at additional easements and planned project sites. Fish surveys and aquatic habitat inventories were conducted at project sites prior to implementation. Proper selection and implementation of

  8. The spatial structure of habitat selection: A caribou's-eye-view

    Science.gov (United States)

    Mayor, Stephen J.; Schaefer, James A.; Schneider, David C.; Mahoney, Shane P.

    2009-03-01

    Greater understanding of habitat selection requires investigation at the scales at which organisms perceive and respond to their environment. Such knowledge could reveal the relative importance of factors limiting populations and the extent of response to habitat changes, and so guide conservation initiatives. We conducted a novel, spatially explicit analysis of winter habitat selection by caribou ( Rangifer tarandus) in Newfoundland, Canada, to elucidate the spatial scales of habitat selection. We combined conventional hierarchical habitat analysis with a newly developed geospatial approach that quantifies selection across scales as the difference in variance between available and used sites. We used both ordination and univariate analyses of lichen and plant cover, snow hardness and depth. This represents the first use of ordination with geostatistics for the assessment of habitat selection. Caribou habitat selection was driven by shallow, soft snow and high cover of Cladina lichens and was strongest at feeding microsites (craters) and broader feeding areas. Habitat selection was most evident at distance lags of up to 15 km, perhaps an indication of the perceptual abilities of caribou.

  9. Does fragmentation of Urtica habitats affect phytophagous and predatory insects differentially?

    Science.gov (United States)

    Zabel, Jörg; Tscharntke, Teja

    1998-09-01

    Effects of habitat fragmentation on the insect community of stinging nettle (Urtica dioica L.) were studied, using 32 natural nettle patches of different area and degree of isolation in an agricultural landscape. Habitat fragmentation reduced the species richness of Heteroptera, Auchenorrhyncha, and Coleoptera, and the abundance of populations. Habitat isolation and area reduction did not affect all insect species equally. Monophagous herbivores had a higher probability of absence from small patches than all (monophagous and polyphagous) herbivore species, and the percentage of monophagous herbivores increased with habitat area. Abundance and population variability of species were negatively correlated and could both be used as a predictor of the percentage of occupied habitats. Species richness of herbivores correlated (positively) with habitat area, while species richness of predators correlated (negatively) with habitat isolation. In logistic regressions, the probability of absence of monophagous herbivores from habitat patches could only be explained by habitat area (in 4 out of 10 species) and predator absence probability only by habitat isolation (in 3 out of 14 species). Presumably because of the instability of higher-trophic-level populations and dispersal limitation, predators were more affected by habitat isolation than herbivores, while they did not differ from herbivore populations with respect to abundance or variability. Thus increasing habitat connectivity in the agricultural landscape should primarily promote predator populations.

  10. Island Species Richness Increases with Habitat Diversity

    NARCIS (Netherlands)

    Hortal, J.; Triantis, K.A.; Meiri, S.; Thebault, E.M.C.; Sfenthourakis, S.

    2009-01-01

    Species richness is commonly thought to increase with habitat diversity. However, a recent theoretical model aiming to unify niche and island biogeography theories predicted a hump-shaped relationship between richness and habitat diversity. Given the contradiction between model results and previous

  11. Variação de temperatura do músculo quadríceps femoral exposto a duas modalidades de crioterapia por meio de termografia

    OpenAIRE

    Carvalho,Alberito Rodrigo de; Medeiros,Daiane Lazzeri de; Souza,Francieli Tibes de; Paula,Grazieli Francine de; Barbosa,Patrícia Mantovani; Vasconcellos,Paula Renata Olegini; Buzanello,Márcia Rosângela; Bertolini,Gladson Ricardo Flor

    2012-01-01

    INTRODUÇÃO: Crioterapia é qualquer forma de aplicação terapêutica de frio que leva à diminuição da temperatura dos tecidos. OBJETIVO: Comparar as variações na temperatura superficial do músculo quadríceps femoral, em três momentos distintos, quando expostos a duas modalidades de crioterapia: sacos com gelo ou sacos contendo mistura de gelo e água. MATERIAIS E MÉTODOS: Participaram do estudo 18 indivíduos, com idade entre 18 e 25 anos, de ambos os sexos. Em cada voluntário foi realizada, simul...

  12. CADDIS Volume 2. Sources, Stressors and Responses: Physical Habitat - Detailed Conceptual Diagram

    Science.gov (United States)

    Introduction to the Physical Habitat module, when to list Physical Habitat as a candidate cause, ways to measure Physical Habitat, simple and detailed conceptual diagrams for Physical Habitat, Physical Habitat module references and literature reviews.

  13. CADDIS Volume 2. Sources, Stressors and Responses: Physical Habitat - Simple Conceptual Diagram

    Science.gov (United States)

    Introduction to the Physical Habitat module, when to list Physical Habitat as a candidate cause, ways to measure Physical Habitat, simple and detailed conceptual diagrams for Physical Habitat, Physical Habitat module references and literature reviews.

  14. Pollen and gene flow in fragmented habitats

    NARCIS (Netherlands)

    Kwak, Manja M.; Velterop, Odilia; van Andel, Jelte

    . Habitat fragmentation affects both plants and pollinators. Habitat fragmentation leads to changes in species richness, population number and size, density, and shape, thus to changes in the spatial arrangement of flowers. These changes influence the amount of food for flower-visiting insects and

  15. Somaclonal variation on in vitro callus culture potato cultivars Variação somaclonal in vitro em cultura de calos de cultivares de batata

    Directory of Open Access Journals (Sweden)

    Patricia N. Bordallo

    2004-06-01

    Full Text Available Synthetic seeds can be an alternative for those species in which botanical seeds are not viable. One of the major problems of in vitro plant cultivation is the high level of somaclonal variation. The most common factors affecting somaclonal variation are genotype, explant source, in vitro period and cultivation conditions in which the culture is established. In this work, calli were induced using leaf and stem explants of the commercial potato cultivars Achat, Baraka, Baronesa, Bintje, and Contenda in MS culture media supplemented with 1.65 mM of picloram and 11.5 mM of 2,4-D. Seventy and 90 days after induction, DNA samples of 40 calli were compared concerning the effects of the two explant (leaf and stem and two growth regulator sources on five potatoes cultivars. A total of 20 arbitrary sequence primers were evaluated. The RAPD pattern generated by these primers suggested a high percentage of polymorphic fragments among the five genotypes, indicating a high level of genetic variation among cultivars. Cultivar Baronesa showed the highest number of polymorphic fragments for all treatments. The cultivar Contenda showed the smallest somaclonal variation, for most of the treatments, except for the treatment which consisted of stem explants, picloram (1.65 mM application, and a 70-day period of callus formation. 'Contenda' is, therefore, the most suitable cultivar for synthetic seed production.A produção de sementes sintéticas pode ser uma altenativa para culturas, cuja produção de sementes botânicas não é viável. Um dos principais problemas do cultivo de planta in vitro é o alto nível de variação somaclonal resultante. Os fatores mais comuns que afetam a variação somaclonal são genótipo, fonte de explante e duração e condições de cultivo. Neste trabalho, calos foram induzidos utilizando explantes de folha e caule das cultivares comerciais de batata Achat, Baraka, Baronesa, Bintje e Contenda em meio de cultura MS, suplementado

  16. Zonation and habitat selection on a reclaimed coastal foredune ...

    African Journals Online (AJOL)

    Three distinct zones, four habitats and six subhabitats were identified. Zonation and habitat selection appeared to be related to cover for two small mammal species. The arthropod orders were less susceptible to zonation and strict habitat selection, although some of the species showed selection. The normally unfavourable ...

  17. Habitat Evaluation Procedures Report; Graves Property - Yakama Nation.

    Energy Technology Data Exchange (ETDEWEB)

    Ashley, Paul; Muse, Anthony

    2008-02-01

    A habitat evaluation procedures (HEP) analysis was conducted on the Graves property (140 acres) in June 2007 to determine the number of habitat units to credit Bonneville Power Administration (BPA) for providing funds to acquire the property as partial mitigation for habitat losses associated with construction of McNary Dam. HEP surveys also documented the general ecological condition of the property. The Graves property was significantly damaged from past/present livestock grazing practices. Baseline HEP surveys generated 284.28 habitat units (HUs) or 2.03 HUs per acre. Of these, 275.50 HUs were associated with the shrubsteppe/grassland cover type while 8.78 HUs were tied to the riparian shrub cover type.

  18. Variações anatômicas em Lymnaea columella (Mollusca, Gastropoda

    Directory of Open Access Journals (Sweden)

    Marlene T. Ueta

    1977-12-01

    Full Text Available Foram estudadas variações anatômicas de espécimes de L. columella coletados de diferentes criadouros situados em diversos Municípios do Estado de São Paulo: Campinas, Americana, Atibaia, Pirassununga, Caçapava e Taubaté. As comparações morfométricas foram baseadas em estudos do aparelho genital, rim e rádula. Foram medidos, para cada criadouro, os comprimentos do conjunto útero-vagina, dueto da espermateca, prepúcio e bainha do pênis. Foram ainda calculados os índices de relação entre bainha do pênis/prepúcio e estabelecidos os coeficientes de correlação entre comprimento da concha e comprimento do prepúcio. Cortes longitudiais do complexo peniano foram também objeto de estudo. Em relação a rádula foram determinados o número de fileiras transversais e o número de dentes por fileira, e estabelecida uma fórmula radular aproximada para os diversos criadouros.Soft parts of Lymnaea columella from ten populations from the State of São Paulo were studied in order to determine morphometric variations. These morphometric cornparisons were made upon reproductive system, kidney and radula of snail samples collected in different municipalities: Campinas, Americana, Atibaia, Pirassununga, Caçapava and Taubaté. Length measurementes of uterus, duct of spermatheca, prepuce and penis sheath were taken; the ratio penis sheath/prepuce and correlation coefficients between length of shell and length of prepuce were established. Longitudinal sections of penial complex were also studied. The number of trans verse rows, number of teeth per rows and the length of shell were determined. For each sample, the radular formula was indicated.

  19. Application of habitat thresholds in conservation: Considerations, limitations, and future directions

    Directory of Open Access Journals (Sweden)

    Yntze van der Hoek

    2015-01-01

    Full Text Available Habitat thresholds are often interpreted as the minimum required area of habitat, and subsequently promoted as conservation targets in natural resource policies and planning. Unfortunately, several recent reviews and messages of caution on the application of habitat thresholds in conservation have largely fallen on deaf ears, leading to a dangerous oversimplification and generalization of the concept. We highlight the prevalence of oversimplification/over-generalization of results from habitat threshold studies in policy documentation, the consequences of such over-generalization, and directions for habitat threshold studies that have conservation applications without risking overgeneralization. We argue that in order to steer away from misapplication of habitat thresholds in conservation, we should not focus on generalized nominal habitat values (i.e., amounts or percentages of habitat, but on the use of habitat threshold modeling for comparative exercises of area-sensitivity or the identification of environmental dangers. In addition, we should remain focused on understanding the processes and mechanisms underlying species responses to habitat change. Finally, studies could that focus on deriving nominal value threshold amounts should do so only if the thresholds are detailed, species-specific, and translated to conservation targets particular to the study area only.

  20. Habitat Concepts for Deep Space Exploration

    Science.gov (United States)

    Smitherman, David; Griffin, Brand N.

    2014-01-01

    Future missions under consideration requiring human habitation beyond the International Space Station (ISS) include deep space habitats in the lunar vicinity to support asteroid retrieval missions, human and robotic lunar missions, satellite servicing, and Mars vehicle servicing missions. Habitat designs are also under consideration for missions beyond the Earth-Moon system, including transfers to near-Earth asteroids and Mars orbital destinations. A variety of habitat layouts have been considered, including those derived from the existing ISS designs and those that could be fabricated from the Space Launch System (SLS) propellant tanks. This paper presents a comparison showing several options for asteroid, lunar, and Mars mission habitats using ISS derived and SLS derived modules and identifies some of the advantages and disadvantages inherent in each. Key findings indicate that the larger SLS diameter modules offer built-in compatibility with the launch vehicle, single launch capability without on-orbit assembly, improved radiation protection, lighter structures per unit volume, and sufficient volume to accommodate consumables for long duration missions without resupply. The information provided with the findings includes mass and volume comparison data that should be helpful to future exploration mission planning efforts.

  1. Deep Space Habitat Wireless Smart Plug

    Science.gov (United States)

    Morgan, Joseph A.; Porter, Jay; Rojdev, Kristina; Carrejo, Daniel B.; Colozza, Anthony J.

    2014-01-01

    NASA has been interested in technology development for deep space exploration, and one avenue of developing these technologies is via the eXploration Habitat (X-Hab) Academic Innovation Challenge. In 2013, NASA's Deep Space Habitat (DSH) project was in need of sensors that could monitor the power consumption of various devices in the habitat with added capability to control the power to these devices for load shedding in emergency situations. Texas A&M University's Electronic Systems Engineering Technology Program (ESET) in conjunction with their Mobile Integrated Solutions Laboratory (MISL) accepted this challenge, and over the course of 2013, several undergraduate students in a Capstone design course developed five wireless DC Smart Plugs for NASA. The wireless DC Smart Plugs developed by Texas A&M in conjunction with NASA's Deep Space Habitat team is a first step in developing wireless instrumentation for future flight hardware. This paper will further discuss the X-Hab challenge and requirements set out by NASA, the detailed design and testing performed by Texas A&M, challenges faced by the team and lessons learned, and potential future work on this design.

  2. Demographic and habitat requirements for conservation of bull trout

    Science.gov (United States)

    Bruce E. Rieman; John D. Mclntyre

    1993-01-01

    Elements in bull trout biology, population dynamics, habitat, and biotic interactions important to conservation of the species are identified. Bull trout appear to have more specific habitat requirements than other salmonids, but no critical thresholds of acceptable habitat condition were found. Size, temporal variation, and spatial distribution are likely to influence...

  3. Tracking changes and preventing loss in critical tiger habitat.

    Science.gov (United States)

    Joshi, Anup R; Dinerstein, Eric; Wikramanayake, Eric; Anderson, Michael L; Olson, David; Jones, Benjamin S; Seidensticker, John; Lumpkin, Susan; Hansen, Matthew C; Sizer, Nigel C; Davis, Crystal L; Palminteri, Suzanne; Hahn, Nathan R

    2016-04-01

    The global population of wild tigers remains dangerously low at fewer than 3500 individuals. Habitat loss, along with poaching, can undermine the international target recovery of doubling the number of wild tigers by 2022. Using a new satellite-based monitoring system, we analyzed 14 years of forest loss data within the 76 landscapes (ranging from 278 to 269,983 km(2)) that have been prioritized for conservation of wild tigers. Our analysis provides an update of the status of tiger habitat and describes new applications of technology to detect precisely where forest loss is occurring in order to curb future habitat loss. Across the 76 landscapes, forest loss was far less than anticipated (79,597 ± 22,629 km(2), 7.7% of remaining habitat) over the 14-year study period (2001-2014). Habitat loss was unevenly distributed within a subset of 29 landscapes deemed most critical for doubling wild tiger populations: 19 showed little change (1.5%), whereas 10 accounted for more than 98% (57,392 ± 16,316 km(2)) of habitat loss. Habitat loss in source population sites within 76 landscapes ranged from no loss to 435 ± 124 km(2) ([Formula: see text], SD = 89, total = 1676 ± 476 km(2)). Doubling the tiger population by 2022 requires moving beyond tracking annual changes in habitat. We highlight near-real-time forest monitoring technologies that provide alerts of forest loss at relevant spatial and temporal scales to prevent further erosion.

  4. Tracing multi-habitat support of coastal fishes

    Science.gov (United States)

    Hydrologic linkages among coastal wetland and nearshore areas allow coastal fish to move among the habitats, which has led to a variety of habitat use patterns. In the Great Lakes, fine-scale microchemical analyses of yellow perch otoliths have revealed life-history categories th...

  5. Habitat heterogeneity influences restoration efficacy: Implications of a habitat-specific management regime for an invaded marsh

    Science.gov (United States)

    Tang, Long; Gao, Yang; Wang, Cheng-Huan; Li, Bo; Chen, Jia-Kuan; Zhao, Bin

    2013-07-01

    Invasive species have to be managed to prevent adverse consequences. Spartina alterniflora has invaded many marshes where salinity and inundation are often key factors affecting vegetation. The former was surface clipped twice and native Phragmites australis was planted in invaded zones to examine the effects of habitat properties on the efficacy of invader control and native restoration. The results showed that two clipping treatments almost eliminated S. alterniflora in the zones with long inundation periods of 80 h/15 d but stimulated compensatory growth of S. alterniflora in the zones with short inundation periods. Transplanted P. australis performed better over time in zones with low salinity (removal of the above-ground parts of S. alterniflora should be used only in the middle tidal zones and that native vegetation should be planted in zones above the mean high water level while the others zones in the saltmarsh should be restored to mud flats. Usually, invasive plants can flourish in highly heterogeneous habitats, which can influence management efficacy by influencing the re-growth of treated invaders and the performance of restored native species. Therefore, habitat-specific management regimes for invasive species can be expected to be more efficient because of their dependence on specific habitats.

  6. Coefficients of productivity for Yellowstone's grizzly bear habitat

    Science.gov (United States)

    Mattson, David John; Barber, Kim; Maw, Ralene; Renkin, Roy

    2004-01-01

    This report describes methods for calculating coefficients used to depict habitat productivity for grizzly bears in the Yellowstone ecosystem. Calculations based on these coefficients are used in the Yellowstone Grizzly Bear Cumulative Effects Model to map the distribution of habitat productivity and account for the impacts of human facilities. The coefficients of habitat productivity incorporate detailed information that was collected over a 20-year period (1977-96) on the foraging behavior of Yellowstone's bears and include records of what bears were feeding on, when and where they fed, the extent of that feeding activity, and relative measures of the quantity consumed. The coefficients also incorporate information, collected primarily from 1986 to 1992, on the nutrient content of foods that were consumed, their digestibility, characteristic bite sizes, and the energy required to extract and handle each food. Coefficients were calculated for different time periods and different habitat types, specific to different parts of the Yellowstone ecosystem. Stratifications included four seasons of bear activity (spring, estrus, early hyperphagia, late hyperphagia), years when ungulate carrion and whitebark pine seed crops were abundant versus not, areas adjacent to (bear activity in each region, habitat type, and time period were incorporated into calculations, controlling for the effects of proximity to human facilities. The coefficients described in this report and associated estimates of grizzly bear habitat productivity are unique among many efforts to model the conditions of bear habitat because calculations include information on energetics derived from the observed behavior of radio-marked bears.

  7. Using urban forest assessment tools to model bird habitat potential

    Science.gov (United States)

    Lerman, Susannah B.; Nislow, Keith H.; Nowak, David J.; DeStefano, Stephen; King, David I.; Jones-Farrand, D. Todd

    2014-01-01

    The alteration of forest cover and the replacement of native vegetation with buildings, roads, exotic vegetation, and other urban features pose one of the greatest threats to global biodiversity. As more land becomes slated for urban development, identifying effective urban forest wildlife management tools becomes paramount to ensure the urban forest provides habitat to sustain bird and other wildlife populations. The primary goal of this study was to integrate wildlife suitability indices to an existing national urban forest assessment tool, i-Tree. We quantified available habitat characteristics of urban forests for ten northeastern U.S. cities, and summarized bird habitat relationships from the literature in terms of variables that were represented in the i-Tree datasets. With these data, we generated habitat suitability equations for nine bird species representing a range of life history traits and conservation status that predicts the habitat suitability based on i-Tree data. We applied these equations to the urban forest datasets to calculate the overall habitat suitability for each city and the habitat suitability for different types of land-use (e.g., residential, commercial, parkland) for each bird species. The proposed habitat models will help guide wildlife managers, urban planners, and landscape designers who require specific information such as desirable habitat conditions within an urban management project to help improve the suitability of urban forests for birds.

  8. Steelhead Critical Habitat, Central Valley - NOAA [ds123

    Data.gov (United States)

    California Natural Resource Agency — This layer depicts areas designated for Steelhead Critical Habitat as well as habitat type and quality in the California Central Valley Evolutionary Significant Unit...

  9. Landscape structure shapes habitat finding ability in a butterfly.

    Directory of Open Access Journals (Sweden)

    Erik Öckinger

    Full Text Available Land-use intensification and habitat fragmentation is predicted to impact on the search strategies animals use to find habitat. We compared the habitat finding ability between populations of the speckled wood butterfly (Pararge aegeria L. from landscapes that differ in degree of habitat fragmentation. Naïve butterflies reared under standardized laboratory conditions but originating from either fragmented agricultural landscapes or more continuous forested landscapes were released in the field, at fixed distances from a target habitat patch, and their flight paths were recorded. Butterflies originating from fragmented agricultural landscapes were better able to find a woodlot habitat from a distance compared to conspecifics from continuous forested landscapes. To manipulate the access to olfactory information, a subset of individuals from both landscape types were included in an antennae removal experiment. This confirmed the longer perceptual range for butterflies from agricultural landscapes and indicated the significance of both visual and olfactory information for orientation towards habitat. Our results are consistent with selection for increased perceptual range in fragmented landscapes to reduce dispersal costs. An increased perceptual range will alter the functional connectivity and thereby the chances for population persistence for the same level of structural connectivity in a fragmented landscape.

  10. Landscape Structure Shapes Habitat Finding Ability in a Butterfly

    Science.gov (United States)

    Öckinger, Erik; Van Dyck, Hans

    2012-01-01

    Land-use intensification and habitat fragmentation is predicted to impact on the search strategies animals use to find habitat. We compared the habitat finding ability between populations of the speckled wood butterfly (Pararge aegeria L.) from landscapes that differ in degree of habitat fragmentation. Naïve butterflies reared under standardized laboratory conditions but originating from either fragmented agricultural landscapes or more continuous forested landscapes were released in the field, at fixed distances from a target habitat patch, and their flight paths were recorded. Butterflies originating from fragmented agricultural landscapes were better able to find a woodlot habitat from a distance compared to conspecifics from continuous forested landscapes. To manipulate the access to olfactory information, a subset of individuals from both landscape types were included in an antennae removal experiment. This confirmed the longer perceptual range for butterflies from agricultural landscapes and indicated the significance of both visual and olfactory information for orientation towards habitat. Our results are consistent with selection for increased perceptual range in fragmented landscapes to reduce dispersal costs. An increased perceptual range will alter the functional connectivity and thereby the chances for population persistence for the same level of structural connectivity in a fragmented landscape. PMID:22870227

  11. Determination of Habitat Requirements For Birds in Suburban Areas

    Science.gov (United States)

    Jack Ward Thomas; Richard M. DeGraaf; Joseph C. Mawson

    1977-01-01

    Songbird populations can be related to habitat components by a method that allows the simultaneous determination of habitat requirements for a variety of species . Through correlation and multiple-regression analyses, 10 bird species were studied in a suburban habitat, which was stratified according to human density. Variables used to account for bird distribution...

  12. Key tiger habitats in the Garo Hills of Meghalaya

    Science.gov (United States)

    Ashish Kumar; Bruce G. Marcot

    2010-01-01

    We describe assumed tiger habitat characteristics and attempt to identify potential tiger habitats in the Garo Hills region of Meghalaya, North East India. Conserving large forest tracts and protected wildlife habitats provides an opportunity for restoring populations of wide-ranging wildlife such as tigers and elephants. Based on limited field observations coupled...

  13. The value of carbon sequestration and storage in coastal habitats

    Science.gov (United States)

    Beaumont, N. J.; Jones, L.; Garbutt, A.; Hansom, J. D.; Toberman, M.

    2014-01-01

    Coastal margin habitats are globally significant in terms of their capacity to sequester and store carbon, but their continuing decline, due to environmental change and human land use decisions, is reducing their capacity to provide this ecosystem service. In this paper the UK is used as a case study area to develop methodologies to quantify and value the ecosystem service of blue carbon sequestration and storage in coastal margin habitats. Changes in UK coastal habitat area between 1900 and 2060 are documented, the long term stocks of carbon stored by these habitats are calculated, and the capacity of these habitats to sequester CO2 is detailed. Changes in value of the carbon sequestration service of coastal habitats are then projected for 2000-2060 under two scenarios, the maintenance of the current state of the habitat and the continuation of current trends of habitat loss. If coastal habitats are maintained at their current extent, their sequestration capacity over the period 2000-2060 is valued to be in the region of £1 billion UK sterling (3.5% discount rate). However, if current trends of habitat loss continue, the capacity of the coastal habitats both to sequester and store CO2 will be significantly reduced, with a reduction in value of around £0.25 billion UK sterling (2000-2060; 3.5% discount rate). If loss-trends due to sea level rise or land reclamation worsen, this loss in value will be greater. This case study provides valuable site specific information, but also highlights global issues regarding the quantification and valuation of carbon sequestration and storage. Whilst our ability to value ecosystem services is improving, considerable uncertainty remains. If such ecosystem valuations are to be incorporated with confidence into national and global policy and legislative frameworks, it is necessary to address this uncertainty. Recommendations to achieve this are outlined.

  14. Hydrologic and water-quality rehabilitation of environments for suitable fish habitat

    Science.gov (United States)

    Zhao, C. S.; Yang, S. T.; Xiang, H.; Liu, C. M.; Zhang, H. T.; Yang, Z. L.; Zhang, Y.; Sun, Y.; Mitrovic, S. M.; Yu, Q.; Lim, R. P.

    2015-11-01

    Aquatic ecological rehabilitation is attracting increasing public and research attention, but without knowledge of the responses of aquatic species to their habitats the success of habitat restoration is uncertain. Thus efficient study of species response to habitat, through which to prioritize the habitat factors influencing aquatic ecosystems, is highly important. However many current models have too high requirement for assemblage information and have great bias in results due to consideration of only the species' attribute of presence/absence, abundance or biomass, thus hindering the wider utility of these models. This paper, using fish as a case, presents a framework for identification of high-priority habitat factors based on the responses of aquatic species to their habitats, using presence/absence, abundance and biomass data. This framework consists of four newly developed sub-models aiming to determine weightings for the evaluation of species' contributions to their communities, to quantitatively calculate an integrated habitat suitability index for multi-species based on habitat factors, to assess the suitable probability of habitat factors and to assess the rehabilitation priority of habitat factors. The framework closely links hydrologic, physical and chemical habitat factors to fish assemblage attributes drawn from monitoring datasets on hydrology, water quality and fish assemblages at a total of 144 sites, where 5084 fish were sampled and tested. Breakpoint identification techniques based on curvature in cumulated dominance along with a newly developed weighting calculation model based on theory of mass systems were used to help identify the dominant fish, based on which the presence and abundance of multiple fish were normalized to estimate the integrated habitat suitability index along gradients of various factors, based on their variation with principal habitat factors. Then, the appropriate probability of every principal habitat factor was

  15. Chinook Critical Habitat, Central Valley - NOAA [ds125

    Data.gov (United States)

    California Department of Resources — This layer depicts areas designated for Chinook Critical Habitat as well as habitat type and quality in the Central Valley Spring-run Evolutionary Significant Unit...

  16. Chinook Critical Habitat, Central Valley - NOAA [ds125

    Data.gov (United States)

    California Natural Resource Agency — This layer depicts areas designated for Chinook Critical Habitat as well as habitat type and quality in the Central Valley Spring-run Evolutionary Significant Unit...

  17. Habitat, food, and small mammal community structure in Namaqualand

    Directory of Open Access Journals (Sweden)

    M. van Deventer

    2006-12-01

    Full Text Available The effect of habitat differences and food availability on small mammal (rodent and elephant shrew species richness, diversity, density and biomass was investigated in Namaqualand, South Africa. Species richness in the three habitats sampled, namely Upland Succulent Karoo, Dry Riverine Shrub and North-western Mountain Renosterveld was low, with only 2–4 species per habitat. Rodents trapped were predominantly Gerbillurus paeba and Aethomys namaquensis, with fewer Mus minutoides and Petromyscus sp. The only non-rodent was the elephant shrew Elephantulus edwardii. Ten habitat features, the percentage of total plant cover, tree cover, shrub cover, grass cover, plant litter, total basal cover, sand, gravel or rock cover, and the dominant plant height were recorded at 30 randomly chosen points on five sampling grids in each habitat. Small mammal density and biomass was significantly correlated with food availability (green foliage cover, seeds, and relative density and biomass of insects. Species richness and diversity of small mammals were significantly correlated with shrub cover. Numbers and biomass of specific species correlated significantly with different habitat features in each case.

  18. West Foster Creek 2007 Follow-up Habitat Evaluation Procedures (HEP) Report.

    Energy Technology Data Exchange (ETDEWEB)

    Ashley, Paul R.

    2008-02-01

    A follow-up habitat evaluation procedures (HEP) analysis was conducted on the West Foster Creek (Smith acquisition) wildlife mitigation site in May 2007 to determine the number of additional habitat units to credit Bonneville Power Administration (BPA) for providing funds to enhance and maintain the project site as partial mitigation for habitat losses associated with construction of Grand Coulee Dam. The West Foster Creek 2007 follow-up HEP survey generated 2,981.96 habitat units (HU) or 1.51 HUs per acre for a 34% increase (+751.34 HUs) above baseline HU credit (the 1999 baseline HEP survey generated 2,230.62 habitat units or 1.13 HUs per acre). The 2007 follow-up HEP analysis yielded 1,380.26 sharp-tailed grouse (Tympanuchus phasianellus) habitat units, 879.40 mule deer (Odocoileus hemionus) HUs, and 722.29 western meadowlark (Sturnella neglecta) habitat units. Mule deer and sharp-tailed grouse habitat units increased by 346.42 HUs and 470.62 HUs respectively over baseline (1999) survey results due largely to cessation of livestock grazing and subsequent passive restoration. In contrast, the western meadowlark generated slightly fewer habitat units in 2007 (-67.31) than in 1999, because of increased shrub cover, which lowers habitat suitability for that species.

  19. Lessons learned while integrating habitat, dispersal, disturbance, and life-history traits into species habitat models under climate change

    Science.gov (United States)

    Louis R. Iverson; Anantha M. Prasad; Stephen N. Matthews; Matthew P. Peters

    2011-01-01

    We present an approach to modeling potential climate-driven changes in habitat for tree and bird species in the eastern United States. First, we took an empirical-statistical modeling approach, using randomForest, with species abundance data from national inventories combined with soil, climate, and landscape variables, to build abundance-based habitat models for 134...

  20. Stream Habitat Reach Summary - North Coast [ds63

    Data.gov (United States)

    California Natural Resource Agency — The shapefile is based on habitat unit level data summarized at the stream reach level. The database represents salmonid stream habitat surveys from 645 streams of...

  1. Habitat classification modelling with incomplete data: Pushing the habitat envelope

    Science.gov (United States)

    Phoebe L. Zarnetske; Thomas C. Edwards; Gretchen G. Moisen

    2007-01-01

    Habitat classification models (HCMs) are invaluable tools for species conservation, land-use planning, reserve design, and metapopulation assessments, particularly at broad spatial scales. However, species occurrence data are often lacking and typically limited to presence points at broad scales. This lack of absence data precludes the use of many statistical...

  2. Evaluation of Life History Diversity, Habitat Connectivity, and Survival Benefits Associated with Habitat Restoration Actions in the Lower Columbia River and Estuary, Annual Report 2010

    Energy Technology Data Exchange (ETDEWEB)

    Diefenderfer, Heida L.; Johnson, Gary E.; Sather, Nichole K.; Skalski, J. R.; Dawley, Earl M.; Coleman, Andre M.; Ostrand, Kenneth G.; Hanson, Kyle C.; Woodruff, Dana L.; Donley, Erin E.; Ke, Yinghai; Buenau, Kate E.; Bryson, Amanda J.; Townsend, Richard L.

    2011-10-01

    This report describes the 2010 research conducted under the U.S. Army Corps of Engineers (USACE) project EST-P-09-1, titled Evaluation of Life History Diversity, Habitat Connectivity, and Survival Benefits Associated with Habitat Restoration Actions in the Lower Columbia River and Estuary, and known as the 'Salmon Benefits' study. The primary goal of the study is to establish scientific methods to quantify habitat restoration benefits to listed salmon and trout in the lower Columbia River and estuary (LCRE) in three required areas: habitat connectivity, early life history diversity, and survival (Figure ES.1). The general study approach was to first evaluate the state of the science regarding the ability to quantify benefits to listed salmon and trout from habitat restoration actions in the LCRE in the 2009 project year, and then, if feasible, in subsequent project years to develop quantitative indices of habitat connectivity, early life history diversity, and survival. Based on the 2009 literature review, the following definitions are used in this study. Habitat connectivity is defined as a landscape descriptor concerning the ability of organisms to move among habitat patches, including the spatial arrangement of habitats (structural connectivity) and how the perception and behavior of salmon affect the potential for movement among habitats (functional connectivity). Life history is defined as the combination of traits exhibited by an organism throughout its life cycle, and for the purposes of this investigation, a life history strategy refers to the body size and temporal patterns of estuarine usage exhibited by migrating juvenile salmon. Survival is defined as the probability of fish remaining alive over a defined amount of space and/or time. The objectives of the 4-year study are as follows: (1) develop and test a quantitative index of juvenile salmon habitat connectivity in the LCRE incorporating structural, functional, and hydrologic components; (2

  3. Livestock grazing, wildlife habitat, and rangeland values

    Science.gov (United States)

    Paul R. Krausman; David E. Naugle; Michael R. Frisina; Rick Northrup; Vernon C. Bleich; William M. Block; Mark C. Wallace; Jeffrey D. Wright

    2009-01-01

    Livestock managers make and implement grazing management decisions to achieve a variety of objectives including livestock production, sustainable grazing, and wildlife habitat enhancement. Assessed values of grazing lands and ranches are often based on aesthetics and wildlife habitat or recreational values, which can exceed agricultural values, thus providing...

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

    Directory of Open Access Journals (Sweden)

    Ryan T. DiGaudio

    2015-10-01

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

  5. Salmon River Habitat Enhancement, Part 1, 1984 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Konopacky, Richard C.

    1985-06-01

    This volume contains reports on subprojects involving the determining of alternatives to enhance salmonid habitat on patented land in Bear Valley Creek, Idaho, coordination activities for habitat projects occurring on streams within fishing areas of the Shoshone-Bannock Indian Tribes, and habitat and fish inventories in the Salmon River. Separate abstracts have been prepared for individual reports. (ACR)

  6. Limitations of habitats as biodiversity surrogates for conservation planning in estuaries.

    Science.gov (United States)

    Shokri, Mohammad Reza; Gladstone, William

    2013-04-01

    Increasing pressures on global biodiversity and lack of data on the number and abundance of species have motivated conservation planners and researchers to use more readily available information as proxies or surrogates for biodiversity. "Habitat" is one of the most frequently used surrogates but its assumed value in marine conservation planning is not often tested. The present study developed and tested three alternative habitat classification schemes of increasing complexity for a large estuary in south-east Australia and tested their effectiveness in predicting spatial variation in macroinvertebrate biodiversity and selecting estuarine protected areas to represent species. The three habitat classification schemes were: (1) broad-scale habitats (e.g., mangroves and seagrass), (2) subdivision of each broad-scale habitat by a suite of environmental variables that varied significantly throughout the estuary, and (3) subdivision of each broad-scale habitat by the subset of environmental variables that best explained spatial variation in macroinvertebrate biodiversity. Macroinvertebrate assemblages differed significantly among the habitats in each classification scheme. For each classification scheme, habitat richness was significantly correlated with species richness, total density of macroinvertebrates, assemblage dissimilarity, and summed irreplaceability. However, in a reserve selection process designed to represent examples of each habitat, no habitat classification scheme represented species significantly better than a random selection of sites. Habitat classification schemes may represent variation in estuarine biodiversity; however, the results of this study suggest they are inefficient in designing representative networks of estuarine protected areas.

  7. Linking habitat mosaics and connectivity in a coral reef seascape

    KAUST Repository

    McMahon, Kelton

    2012-09-04

    Tropical marine ecosystems are under mounting anthropogenic pressure from overfishing and habitat destruction, leading to declines in their structure and function on a global scale. Although maintaining connectivity among habitats within a seascape is necessary for preserving population resistance and resilience, quantifying movements of individuals within seascapes remains challenging. Traditional methods of identifying and valuing potential coral reef fish nursery habitats are indirect, often relying on visual surveys of abundance and correlations of size and biomass among habitats. We used compound-specific stable isotope analyses to determine movement patterns of commercially important fish populations within a coral reef seascape. This approach allowed us to quantify the relative contributions of individuals from inshore nurseries to reef populations and identify migration corridors among important habitats. Our results provided direct measurements of remarkable migrations by juvenile snapper of over 30 km, between nurseries and reefs. We also found significant plasticity in juvenile nursery residency. Although a majority of individuals on coastal reefs had used seagrass nurseries as juveniles, many adults on oceanic reefs had settled directly into reef habitats. Moreover, seascape con figuration played a critical but heretofore unrecognized role in determining connectivity among habitats. Finally, our approach provides key quantitative data necessary to estimate the value of distinctive habitats to ecosystem services provided by seascapes.

  8. Linking habitat mosaics and connectivity in a coral reef seascape

    KAUST Repository

    McMahon, Kelton; Berumen, Michael L.; Thorrold, Simon R.

    2012-01-01

    Tropical marine ecosystems are under mounting anthropogenic pressure from overfishing and habitat destruction, leading to declines in their structure and function on a global scale. Although maintaining connectivity among habitats within a seascape is necessary for preserving population resistance and resilience, quantifying movements of individuals within seascapes remains challenging. Traditional methods of identifying and valuing potential coral reef fish nursery habitats are indirect, often relying on visual surveys of abundance and correlations of size and biomass among habitats. We used compound-specific stable isotope analyses to determine movement patterns of commercially important fish populations within a coral reef seascape. This approach allowed us to quantify the relative contributions of individuals from inshore nurseries to reef populations and identify migration corridors among important habitats. Our results provided direct measurements of remarkable migrations by juvenile snapper of over 30 km, between nurseries and reefs. We also found significant plasticity in juvenile nursery residency. Although a majority of individuals on coastal reefs had used seagrass nurseries as juveniles, many adults on oceanic reefs had settled directly into reef habitats. Moreover, seascape con figuration played a critical but heretofore unrecognized role in determining connectivity among habitats. Finally, our approach provides key quantitative data necessary to estimate the value of distinctive habitats to ecosystem services provided by seascapes.

  9. Habitat and food resources of otters (Mustelidae) in Peninsular Malaysia

    Science.gov (United States)

    Abdul-Patah, P.; Nur-Syuhada, N.; Md-Nor, S.; Sasaki, H.; Md-Zain, B. M.

    2014-09-01

    Habitat and food resources of otters were studied in several locations in Peninsular Malaysia. A total of 210 fecal samples were collected from April 2010 to March 2011 believed to be of otter's were analyzed for their diet composition and their habitat preferences. The DNA testing conducted revealed that only 126 samples were identified as Lultrogale perspicillata and Aonyx cinereus with 105 and 21 samples, respectively. Habitat analyses revealed that these two species preferred paddy fields and mangroves as their main habitats but L. perspicillata preferred to hunt near habitat with large water bodies, such as mangroves, rivers, ponds, and lakes. A. cinereus on the other hand, were mainly found near land-based habitat, such as paddy fields, casuarinas forest and oil palms near mangroves. Habitats chosen were influenced by their food preferences where L. perspicillata consumed a variety of fish species with a supplementary diet of prawns, small mammals, and amphibians, compared to A. cinereus which consumed less fish and more non-fish food items, such as insects, crabs, and snails. Since, the most of the otter habitats in this study are not located within the protected areas, conservation effort involving administrations, landowners, private organizations and public are necessary.

  10. Linking habitat mosaics and connectivity in a coral reef seascape.

    Science.gov (United States)

    McMahon, Kelton W; Berumen, Michael L; Thorrold, Simon R

    2012-09-18

    Tropical marine ecosystems are under mounting anthropogenic pressure from overfishing and habitat destruction, leading to declines in their structure and function on a global scale. Although maintaining connectivity among habitats within a seascape is necessary for preserving population resistance and resilience, quantifying movements of individuals within seascapes remains challenging. Traditional methods of identifying and valuing potential coral reef fish nursery habitats are indirect, often relying on visual surveys of abundance and correlations of size and biomass among habitats. We used compound-specific stable isotope analyses to determine movement patterns of commercially important fish populations within a coral reef seascape. This approach allowed us to quantify the relative contributions of individuals from inshore nurseries to reef populations and identify migration corridors among important habitats. Our results provided direct measurements of remarkable migrations by juvenile snapper of over 30 km, between nurseries and reefs. We also found significant plasticity in juvenile nursery residency. Although a majority of individuals on coastal reefs had used seagrass nurseries as juveniles, many adults on oceanic reefs had settled directly into reef habitats. Moreover, seascape configuration played a critical but heretofore unrecognized role in determining connectivity among habitats. Finally, our approach provides key quantitative data necessary to estimate the value of distinctive habitats to ecosystem services provided by seascapes.

  11. VT Wildlife Linkage Habitat

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The Wildlife Linkage Habitat Analysis uses landscape scale data to identify or predict the location of potentially significant wildlife linkage...

  12. Habitat hydraulic models - a tool for Danish stream quality assessment?

    DEFF Research Database (Denmark)

    Olsen, Martin

    and hydromorphological and chemical characteristics has to be enlightened (EUROPA, 2005). This study links catchment hydrology, stream discharge and physical habitat in a small Danish stream, the stream Ledreborg, and discusses the utility of habitat hydraulic models in relation to the present criteria and methods used......).  Hydromorphological conditions in the stream are measured through field study, using a habitat mapping approach and modelled using a habitat hydraulic model (RHYHABSIM). Using RHYHABSIM and both "site-specific" and general HSI's, Weighted Usable Area (WUA) for the trout population at different discharges is assessed...... and differences between simulated WUA using "site-specific" and general habitat preferences are discussed. In RHYHABSIM it is possible to use two different approaches to investigate the hydromorphological conditions in a river, the habitat mapping approach used in this project and the representative reach...

  13. Habitat Evaluation Procedures (HEP) Report; Priest River Project, Technical Report 2005.

    Energy Technology Data Exchange (ETDEWEB)

    Entz, Ray

    2005-05-01

    On July 6, 2004, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the Priest River property, an acquisition completed by the Kalispel Tribe of Indians in 2001. Evaluation species and appropriate models include bald eagle, black-capped chickadee, Canada goose, mallard, yellow warbler, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The Priest River Project provides a total of 140.73 Habitat Units (HUs) for the species evaluated. Conifer forest habitat provides 60.05 HUs for bald eagle, black-capped chickadee, and white-tailed deer. Grassland meadow habitat provides 7.39 HUs for Canada goose and mallard. Scrub-shrub vegetation provides 71.13 HUs for mallard, yellow warbler, and white-tailed deer. Open water habitat provides 2.16 HUs for Canada goose and mallard. The objective of using HEP at the Priest River Project and other protected properties is to document the quality and quantity of available habitat for selected wildlife species. In this way, HEP provides information on the relative value of the same area at future points in time so that the effect of management activities on wildlife habitat can be quantified. When combined with other tools, the baseline HEP will be used to determine the most effective on-site management, restoration, and enhancement actions to increase habitat suitability for targeted species. The same process will be replicated every five years to quantitatively evaluate the effectiveness of management strategies in improving and maintaining habitat conditions while providing additional crediting to BPA for enhanced habitat values.

  14. Habitat Evaluation Procedures (HEP) Report; North Eaton Lake, Technical Report 2005.

    Energy Technology Data Exchange (ETDEWEB)

    Entz, Ray

    2005-11-01

    On July 6, 2005, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the North Eaton Lake property, an acquisition completed by the Kalispel Tribe of Indians in November 2004. Evaluation species and appropriate models include bald eagle, black-capped chickadee, Canada goose, mallard, muskrat, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The North Eaton Lake Project provides a total of 235.05 Habitat Units (HUs) for the species evaluated. Open water habitat provides 9.38 HUs for Canada goose, mallard and muskrat. Emergent wetland habitat provides 11.36 HUs for Canada goose, mallard and muskrat. Forested wetland provides 10.97 HUs for bald eagle, black-capped chickadee, mallard and white-tailed deer. Conifer forest habitat provides 203.34 HUs for bald eagle, black-capped chickadee, mallard, and white-tailed deer. The objective of using HEP at the North Eaton Lake Project and other protected properties is to document the quality and quantity of available habitat for selected wildlife species. In this way, HEP provides information on the relative value of the same area at future points in time so that the effect of management activities on wildlife habitat can be quantified. When combined with other tools, the baseline HEP will be used to determine the most effective on-site management, restoration, and enhancement actions to increase habitat suitability for targeted species. The same process will be replicated every five years to quantitatively evaluate the effectiveness of management strategies in improving and maintaining habitat conditions while providing additional crediting to BPA for enhanced habitat values.

  15. Evaluation of habitat suitability models for forest passerines using demographic data

    Science.gov (United States)

    Chadwick D. Rittenhouse; Frank R., III Thompson; William D. Dijak; Joshua J. Millspaugh; Richard L. Clawson

    2010-01-01

    Habitat suitability is often used as a surrogate for demographic responses (i.e., abundance, survival, fecundity, or population viability) in the application of habitat suitability index (HSI) models. Whether habitat suitability actually relates to demographics, however, has rarely been evaluated. We validated HSI models of breeding habitat suitability for wood thrush...

  16. Eder Acquisition 2007 Habitat Evaluation Procedures Report.

    Energy Technology Data Exchange (ETDEWEB)

    Ashley, Paul R.

    2008-01-01

    A habitat evaluation procedures (HEP) analysis was conducted on the Eder acquisition in July 2007 to determine how many protection habitat units to credit Bonneville Power Administration (BPA) for providing funds to acquire the project site as partial mitigation for habitat losses associated with construction of Grand Coulee and Chief Joseph Dams. Baseline HEP surveys generated 3,857.64 habitat units or 1.16 HUs per acre. HEP surveys also served to document general habitat conditions. Survey results indicated that the herbaceous plant community lacked forbs species, which may be due to both livestock grazing and the late timing of the surveys. Moreover, the herbaceous plant community lacked structure based on lower than expected visual obstruction readings (VOR); likely a direct result of livestock impacts. In addition, introduced herbaceous vegetation including cultivated pasture grasses, e.g. crested wheatgrass and/or invader species such as cheatgrass and mustard, were present on most areas surveyed. The shrub element within the shrubsteppe cover type was generally a mosaic of moderate to dense shrubby areas interspersed with open grassland communities while the 'steppe' component was almost entirely devoid of shrubs. Riparian shrub and forest areas were somewhat stressed by livestock. Moreover, shrub and tree communities along the lower reaches of Nine Mile Creek suffered from lack of water due to the previous landowners 'piping' water out of the stream channel.

  17. The micro-habitat methodology. Application protocols

    Energy Technology Data Exchange (ETDEWEB)

    Sabaton, C; Valentin, S; Souchon, Y

    1995-06-01

    A strong need has been felt for guidelines to help various entities in applying the micro-habitat methodology, particularly in impact studies on hydroelectric installations. CEMAGREF and Electricite de France have developed separately two protocols with five major steps: reconnaissance of the river, selection of representative units to be studied in greater depth, morpho-dynamic measurements at one or more rates of discharge and hydraulic modeling, coupling of hydraulic and biological models, calculation of habitat-quality scores for fish, analysis of results. The two approaches give very comparable results and are essentially differentiated by the hydraulic model used. CEMAGREF uses a one-dimensional model requiring measurements at only one discharge rate. Electricite de France uses a simplified model based on measurements at several rates of discharge. This approach is possible when discharge can be controlled in the study area during data acquisition, as is generally the case downstream of hydroelectric installations. The micro-habitat methodology is now a fully operational tool with which to study changes in fish habitat quality in relation to varying discharge. It provides an element of assessment pertinent to the choice of instreaming flow to be maintained downstream of a hydroelectric installation; this information is essential when the flow characteristics (velocity, depth) and the nature of the river bed are the preponderant factors governing habitat suitability for trout or salmon. The ultimate decision must nonetheless take into account any other potentially limiting factors for the biocenoses on the one hand, and the target water use objectives on the other. In many cases, compromises must be found among different uses, different species and different stages in the fish development cycle. (Abstract Truncated)

  18. Habitat assessment for giant pandas in the Qinling Mountain region of China

    Science.gov (United States)

    Feng, Tian-Tian; Van Manen, Frank T.; Zhao, Na-Xun; Li, Ming; Wei, Fu-Wen

    2009-01-01

    Because habitat loss and fragmentation threaten giant pandas (Ailuropoda melanoleuca), habitat protection and restoration are important conservation measures for this endangered species. However, distribution and value of potential habitat to giant pandas on a regional scale are not fully known. Therefore, we identified and ranked giant panda habitat in Foping Nature Reserve, Guanyinshan Nature Reserve, and adjacent areas in the Qinling Mountains of China. We used Mahalanobis distance and 11 digital habitat layers to develop a multivariate habitat signature associated with 247 surveyed giant panda locations, which we then applied to the study region. We identified approximately 128 km2 of giant panda habitat in Foping Nature Reserve (43.6% of the reserve) and 49 km2 in Guanyinshan Nature Reserve (33.6% of the reserve). We defined core habitat areas by incorporating a minimum patch-size criterion (5.5 km2) based on home-range size. Percentage of core habitat area was higher in Foping Nature Reserve (41.8% of the reserve) than Guanyinshan Nature Reserve (26.3% of the reserve). Within the larger analysis region, Foping Nature Reserve contained 32.7% of all core habitat areas we identified, indicating regional importance of the reserve. We observed a negative relationship between distribution of core areas and presence of roads and small villages. Protection of giant panda habitat at lower elevations and improvement of habitat linkages among core habitat areas are important in a regional approach to giant panda conservation.

  19. Migrating birds’ use of stopover habitat in the southwestern United States

    Science.gov (United States)

    Ruth, Janet M.; Diehl, R.H.; Felix, R.K.

    2012-01-01

    In the arid Southwest, migratory birds are known to use riparian stopover habitats; we know less about how migrants use other habitat types during migratory stopover. Using radar data and satellite land-cover data, we determined the habitats with which birds are associated during migration stopover. Bird densities differed significantly by habitat type at all sites in at least one season. In parts of Arizona and New Mexico upland forest supported high densities of migrants, especially in fall. Developed habitat, in areas with little upland forest, also supported high densities of migrants. Scrub/shrub and grassland habitats supported low to intermediate densities, but because these habitat types dominate the Southwestern landscape, they may provide stopover habitat for larger numbers of migratory birds than previously recognized. These results are complicated by continuing challenges related to target identity (i.e., distinguishing among birds, arthropods and bats). Our results suggest that it is too simplistic to (1) consider the arid West as a largely inhospitable landscape in which there are only relatively small oases of habitat that provide the resources needed by all migrants, (2) think of western riparian and upland forests as supporting the majority of migrants in all cases, and (3) consider a particular habitat unimportant for stopover solely on the basis of low densities of migrants.

  20. Monitoring Natura 2000 habitats: habitat 92A0 in central Italy as an example

    Directory of Open Access Journals (Sweden)

    Emanuela Carli

    2016-10-01

    Full Text Available The evaluation and the subsequent monitoring of the conservation status of habitats is one of the key steps in nature protection. While some European countries have tested suitable methodologies, others, including Italy, lack procedures tested at the national level. The aim of this work is to propose a method to assess the conservation status of habitat 92A0 (Salix alba and Populus alba galleries in central Italy, and to test the method using data from the Molise region. We selected parameters that highlight the conservation status of the flora and vegetation in order to assess habitat structures and functions at the site level. After selecting the parameters, we tested them on a training dataset of 22 unpublished phytosociological relevés taken from the whole dataset, which consists of 119 relevés (49 unpublished relevés for the study area, and 70 published relevés for central Italy. We detected the most serious conservation problems in the middle and lower course of the Biferno river: the past use of river terraces for agriculture and continual human interventions on the river water flow have drastically reduced the riparian forests of Molise. Our results show that in areas in which forest structure and floristic composition have been substantially modified, certain alien plant species, particularly Robinia pseudoacacia, Amorpha fruticosa and Erigeron canadensis, have spread extensively along rivers. In the management of riparian forests, actions aimed at maintaining the stratification of the forest, its uneven-agedness and tree species richness may help to ensure the conservation status, as well as favour the restoration, of habitat 92A0.

  1. Scale dependency of American marten (Martes americana) habitat relations [Chapter 12

    Science.gov (United States)

    Andrew J. Shirk; Tzeidle N. Wasserman; Samuel A. Cushman; Martin G. Raphael

    2012-01-01

    Animals select habitat resources at multiple spatial scales; therefore, explicit attention to scale-dependency when modeling habitat relations is critical to understanding how organisms select habitat in complex landscapes. Models that evaluate habitat variables calculated at a single spatial scale (e.g., patch, home range) fail to account for the effects of...

  2. Habitat Evaluation Procedures (HEP) Report; Carey Creek, Technical Report 2005.

    Energy Technology Data Exchange (ETDEWEB)

    Entz, Ray

    2005-05-01

    In August 2002, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the Carey Creek property, an acquisition completed by the Kalispel Tribe of Indians in December 2001. Evaluation species and appropriate models include bald eagle, black-capped chickadee, Canada goose, mallard, yellow warbler, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The Carey Creek Project provides a total of 172.95 Habitat Units (HUs) for the species evaluated. Conifer forest habitat provides 4.91 HUs for bald eagle, black-capped chickadee, and white-tailed deer. Forested wetlands provide 52.68 HUs for bald eagle, black-capped chickadee, mallard, and white-tailed deer. Scrub-shrub wetlands provide 2.82 HUs for mallard, yellow warbler and white-tailed deer. Wet meadow and grassland meadow provide 98.13 HUs for mallard and Canada goose. Emergent wetlands provide 11.53 HUs for mallard, muskrat, and Canada goose. Open water provides 2.88 HUs for Canada goose, mallard, and muskrat. The objective of using HEP at the Carey Creek Project and other protected properties is to document the quality and quantity of available habitat for selected wildlife species. In this way, HEP provides information on the relative value of the same area at future points in time so that the effect of management activities on wildlife habitat can be quantified. When combined with other tools, the baseline HEP will be used to determine the most effective on-site management, restoration, and enhancement actions to increase habitat suitability for targeted species. The same process will be replicated every five years to quantitatively evaluate the effectiveness of management strategies in improving and maintaining habitat conditions while providing additional crediting to BPA for enhanced habitat values.

  3. Smartphone technologies and Bayesian networks to assess shorebird habitat selection

    Science.gov (United States)

    Zeigler, Sara; Thieler, E. Robert; Gutierrez, Ben; Plant, Nathaniel G.; Hines, Megan K.; Fraser, James D.; Catlin, Daniel H.; Karpanty, Sarah M.

    2017-01-01

    Understanding patterns of habitat selection across a species’ geographic distribution can be critical for adequately managing populations and planning for habitat loss and related threats. However, studies of habitat selection can be time consuming and expensive over broad spatial scales, and a lack of standardized monitoring targets or methods can impede the generalization of site-based studies. Our objective was to collaborate with natural resource managers to define available nesting habitat for piping plovers (Charadrius melodus) throughout their U.S. Atlantic coast distribution from Maine to North Carolina, with a goal of providing science that could inform habitat management in response to sea-level rise. We characterized a data collection and analysis approach as being effective if it provided low-cost collection of standardized habitat-selection data across the species’ breeding range within 1–2 nesting seasons and accurate nesting location predictions. In the method developed, >30 managers and conservation practitioners from government agencies and private organizations used a smartphone application, “iPlover,” to collect data on landcover characteristics at piping plover nest locations and random points on 83 beaches and barrier islands in 2014 and 2015. We analyzed these data with a Bayesian network that predicted the probability a specific combination of landcover variables would be associated with a nesting site. Although we focused on a shorebird, our approach can be modified for other taxa. Results showed that the Bayesian network performed well in predicting habitat availability and confirmed predicted habitat preferences across the Atlantic coast breeding range of the piping plover. We used the Bayesian network to map areas with a high probability of containing nesting habitat on the Rockaway Peninsula in New York, USA, as an example application. Our approach facilitated the collation of evidence-based information on habitat selection

  4. Interactive effects of temperature and habitat complexity on freshwater communities.

    Science.gov (United States)

    Scrine, Jennifer; Jochum, Malte; Ólafsson, Jón S; O'Gorman, Eoin J

    2017-11-01

    Warming can lead to increased growth of plants or algae at the base of the food web, which may increase the overall complexity of habitat available for other organisms. Temperature and habitat complexity have both been shown to alter the structure and functioning of communities, but they may also have interactive effects, for example, if the shade provided by additional habitat negates the positive effect of temperature on understory plant or algal growth. This study explored the interactive effects of these two major environmental factors in a manipulative field experiment, by assessing changes in ecosystem functioning (primary production and decomposition) and community structure in the presence and absence of artificial plants along a natural stream temperature gradient of 5-18°C. There was no effect of temperature or habitat complexity on benthic primary production, but epiphytic production increased with temperature in the more complex habitat. Cellulose decomposition rate increased with temperature, but was unaffected by habitat complexity. Macroinvertebrate communities were less similar to each other as temperature increased, while habitat complexity only altered community composition in the coldest streams. There was also an overall increase in macroinvertebrate abundance, body mass, and biomass in the warmest streams, driven by increasing dominance of snails and blackfly larvae. Presence of habitat complexity, however, dampened the strength of this temperature effect on the abundance of macroinvertebrates in the benthos. The interactive effects that were observed suggest that habitat complexity can modify the effects of temperature on important ecosystem functions and community structure, which may alter energy flow through the food web. Given that warming is likely to increase habitat complexity, particularly at higher latitudes, more studies should investigate these two major environmental factors in combination to improve our ability to predict the

  5. Inter-annual variability of North Sea plaice spawning habitat

    Science.gov (United States)

    Loots, C.; Vaz, S.; Koubbi, P.; Planque, B.; Coppin, F.; Verin, Y.

    2010-11-01

    Potential spawning habitat is defined as the area where environmental conditions are suitable for spawning to occur. Spawning adult data from the first quarter (January-March) of the International Bottom Trawl Survey have been used to study the inter-annual variability of the potential spawning habitat of North Sea plaice from 1980 to 2007. Generalised additive models (GAM) were used to create a model that related five environmental variables (depth, bottom temperature and salinity, seabed stress and sediment type) to presence-absence and abundance of spawning adults. Then, the habitat model was applied each year from 1970 to 2007 to predict inter-annual variability of the potential spawning habitat. Predicted responses obtained by GAM for each year were mapped using kriging. A hierarchical classification associated with a correspondence analysis was performed to cluster spawning suitable areas and to determine how they evolved across years. The potential spawning habitat was consistent with historical spawning ground locations described in the literature from eggs surveys. It was also found that the potential spawning habitat varied across years. Suitable areas were located in the southern part of the North Sea and along the eastern coast of England and Scotland in the eighties; they expanded further north from the nineties. Annual survey distributions did not show such northward expansion and remained located in the southern North Sea. This suggests that this species' actual spatial distribution remains stable against changing environmental conditions, and that the potential spawning habitat is not fully occupied. Changes in environmental conditions appear to remain within plaice environmental ranges, meaning that other factors may control the spatial distribution of plaice spawning habitat.

  6. Ecomorphology and phylogenetic risk: Implications for habitat reconstruction using fossil bovids.

    Science.gov (United States)

    Scott, Robert S; Barr, W Andrew

    2014-08-01

    Reconstructions of paleohabitats are necessary aids in understanding hominin evolution. The morphology of species from relevant sites, understood in terms of functional relationships to habitat (termed ecomorphology), offers a direct link to habitat. Bovids are a speciose radiation that includes many habitat specialists and are abundant in the fossil record. Thus, bovids are extremely common in ecomorphological analyses. However, bovid phylogeny and habitat preference are related, which raises the possibility that analyses linking habitat with morphology are not 'taxon free' but 'taxon-dependent.' Here we analyze eight relative dimensions and one shape index of the metatarsal for a sample of 72 bovid species and one antilocaprid. The selected variables have been previously shown to have strong associations with habitat and to have functional explanations for these associations. Phylogenetic generalized least squares analyses of these variables, including habitat and size, resulted in estimates for the parameter lambda (used to model phylogenetic signal) varying from zero to one. Thus, while phylogeny, morphology, and habitat all march together among the bovids, the odds that phylogeny confounds ecomorphological analyses may vary depending on particular morphological characteristics. While large values of lambda do not necessarily indicate that habitat differences are unimportant drivers of morphology, we consider the low value of lambda for relative metatarsal width suggestive that conclusions about habitat built on observations of this particular morphology carry with them less 'phylogenetic risk.' We suggest that the way forward for ecomorphology is grounded in functionally relevant observations and careful consideration of phylogeny designed to bracket probable habitat preferences appropriately. Separate consideration of different morphological variables may help to determine the level of 'phylogenetic risk' attached to conclusions linking habitat and morphology

  7. A concept for extraction of habitat features from laser scanning and hypersprectral imaging for evaluation of Natura 2000 sites - the ChangeHabitats2 project approach

    Science.gov (United States)

    Székely, B.; Kania, A.; Pfeifer, N.; Heilmeier, H.; Tamás, J.; Szöllősi, N.; Mücke, W.

    2012-04-01

    The goal of the ChangeHabitats2 project is the development of cost- and time-efficient habitat assessment strategies by employing effective field work techniques supported by modern airborne remote sensing methods, i.e. hyperspectral imagery and laser scanning (LiDAR). An essential task of the project is the design of a novel field work technique that on the one hand fulfills the reporting requirements of the Flora-Fauna-Habitat (FFH-) directive and on the other hand serves as a reference for the aerial data analysis. Correlations between parameters derived from remotely sensed data and terrestrial field measurements shall be exploited in order to create half- or fully-automated methods for the extraction of relevant Natura2000 habitat parameters. As a result of these efforts a comprehensive conceptual model has been developed for extraction and integration of Natura 2000 relevant geospatial data. This scheme is an attempt to integrate various activities within ChangeHabitats2 project defining pathways of development, as well as encompassing existing data processing chains, theoretical approaches and field work. The conceptual model includes definition of processing levels (similar to those existing in remote sensing), whereas these levels cover the range from the raw data to the extracted habitat feature. For instance, the amount of dead wood (standing or lying on the surface) is an important evaluation criterion for the habitat. The tree trunks lying on the ground surface typically can be extracted from the LiDAR point cloud, and the amount of wood can be estimated accordingly. The final result will be considered as a habitat feature derived from laser scanning data. Furthermore, we are also interested not only in the determination of the specific habitat feature, but also in the detection of its variations (especially in deterioration). In this approach the variation of this important habitat feature is considered to be a differential habitat feature, that can

  8. Smalltooth Sawfish Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for smalltooth sawfish (Pristis pectinatat) as designated by 74 FR 45353, September 2, 2009, Rules and Regulations.

  9. Enhancing and restoring habitat for the desert tortoise

    Science.gov (United States)

    Abella, Scott R.; Berry, Kristin H.

    2016-01-01

    Habitat has changed unfavorably during the past 150 y for the desert tortoise Gopherus agassizii, a federally threatened species with declining populations in the Mojave Desert and western Sonoran Desert. To support recovery efforts, we synthesized published information on relationships of desert tortoises with three habitat features (cover sites, forage, and soil) and candidate management practices for improving these features for tortoises. In addition to their role in soil health and facilitating recruitment of annual forage plants, shrubs are used by desert tortoises for cover and as sites for burrows. Outplanting greenhouse-grown seedlings, protected from herbivory, has successfully restored (>50% survival) a variety of shrubs on disturbed desert soils. Additionally, salvaging and reapplying topsoil using effective techniques is among the more ecologically beneficial ways to initiate plant recovery after severe disturbance. Through differences in biochemical composition and digestibility, some plant species provide better-quality forage than others. Desert tortoises selectively forage on particular annual and herbaceous perennial species (e.g., legumes), and forage selection shifts during the year as different plants grow or mature. Nonnative grasses provide low-quality forage and contribute fuel to spreading wildfires, which damage or kill shrubs that tortoises use for cover. Maintaining a diverse “menu” of native annual forbs and decreasing nonnative grasses are priorities for restoring most desert tortoise habitats. Reducing herbivory by nonnative animals, carefully timing herbicide applications, and strategically augmenting annual forage plants via seeding show promise for improving tortoise forage quality. Roads, another disturbance, negatively affect habitat in numerous ways (e.g., compacting soil, altering hydrology). Techniques such as recontouring road berms to reestablish drainage patterns, vertical mulching (“planting” dead plant material

  10. Variação na qualidade culinária das raízes de mandioca Culinary quality variation in cassava roots

    Directory of Open Access Journals (Sweden)

    José Osmar Lorenzi

    1994-01-01

    Full Text Available A falta de regularidade na qualidade culinária das raízes de mandioca de mesa é um dos fatores de restrição à expansão de seu consumo. Raízes cozidas de boa qualidade, entre outras características, devem apresentar-se, quando esmagadas por um garfo, na forma de uma massa não encaroçada, plástica e não pegajosa. O tempo de cozimento culinário correlaciona-se bem com a qualidade da massa cozida, isto é, quanto menor esse tempo, melhor a massa gerada. Dessa forma, neste trabalho, a duração do tempo de cozimento (DTC foi usada como método indireto e expedito para avaliação da qualidade culinária das raízes de mandioca. Os fatores que interferem na DTC podem ser reunidos em dois grupos: (a intrínsecos: variação dentro e entre raízes da mesma planta e entre plantas da mesma variedade; (b extrínsecos: variação em função do genótipo, do ambiente e do estado fisiológico das plantas. Estudos preliminares realizados pelo Instituto Agronômico (IAC tiveram por objetivos verificar e quantificar a magnitude dessas variações. Foram desenvolvidos dois experimentos de campo, em dois solos distintos, utilizando cinco variedades amostradas mensalmente, do 7.° ao 15.° mês de idade das plantas. A DTC foi determinada a partir de água fervente, em subamostras de cada raiz da planta. Os resultados mais relevantes mostraram que: (a a DTC diminuiu, de 10 a 14 minutos, da base para a ponta da raiz; (b a amplitude média de variação entre as raízes de uma mesma planta foi de 11, 10 e 27 minutos, respectivamente, para plantas com 8, 12 e 15 meses; (c houve diferenças na DTC para variedades (9 minutos e para tipos de solo (17 minutos; (d o efeito médio de época de colheita foi de 19 minutos. O período de menor DTC foi do 7.° ao 12.° mês de idade das plantas.Irregular culinary quality of cassava roots has been one of the major point that restricts its expansion for human consumption. A good quality cassava root, after cooking

  11. Does Wyoming's Core Area Policy Protect Winter Habitats for Greater Sage-Grouse?

    Science.gov (United States)

    Smith, Kurt T.; Beck, Jeffrey L.; Pratt, Aaron C.

    2016-10-01

    Conservation reserves established to protect important habitat for wildlife species are used world-wide as a wildlife conservation measure. Effective reserves must adequately protect year-round habitats to maintain wildlife populations. Wyoming's Sage-Grouse Core Area policy was established to protect breeding habitats for greater sage-grouse ( Centrocercus urophasianus). Protecting only one important seasonal habitat could result in loss or degradation of other important habitats and potential declines in local populations. The purpose of our study was to identify the timing of winter habitat use, the extent which individuals breeding in Core Areas used winter habitats, and develop resource selection functions to assess effectiveness of Core Areas in conserving sage-grouse winter habitats in portions of 5 Core Areas in central and north-central Wyoming during winters 2011-2015. We found that use of winter habitats occured over a longer period than current Core Area winter timing stipulations and a substantial amount of winter habitat outside of Core Areas was used by individuals that bred in Core Areas, particularly in smaller Core Areas. Resource selection functions for each study area indicated that sage-grouse were selecting habitats in response to landscapes dominated by big sagebrush and flatter topography similar to other research on sage-grouse winter habitat selection. The substantial portion of sage-grouse locations and predicted probability of selection during winter outside small Core Areas illustrate that winter requirements for sage-grouse are not adequately met by existing Core Areas. Consequently, further considerations for identifying and managing important winter sage-grouse habitats under Wyoming's Core Area Policy are warranted.

  12. Coastal vertebrate exposure to predicted habitat changes due to sea level rise

    Science.gov (United States)

    Hunter, Elizabeth A.; Nibbelink, Nathan P.; Alexander, Clark R.; Barrett, Kyle; Mengak, Lara F.; Guy, Rachel; Moore, Clinton; Cooper, Robert J.

    2015-01-01

    Sea level rise (SLR) may degrade habitat for coastal vertebrates in the Southeastern United States, but it is unclear which groups or species will be most exposed to habitat changes. We assessed 28 coastal Georgia vertebrate species for their exposure to potential habitat changes due to SLR using output from the Sea Level Affecting Marshes Model and information on the species’ fundamental niches. We assessed forecasted habitat change up to the year 2100 using three structural habitat metrics: total area, patch size, and habitat permanence. Almost all of the species (n = 24) experienced negative habitat changes due to SLR as measured by at least one of the metrics. Salt marsh and ocean beach habitats experienced the most change (out of 16 categorical land cover types) across the three metrics and species that used salt marsh extensively (rails and marsh sparrows) were ranked highest for exposure to habitat changes. Species that nested on ocean beaches (Diamondback Terrapins, shorebirds, and terns) were also ranked highly, but their use of other foraging habitats reduced their overall exposure. Future studies on potential effects of SLR on vertebrates in southeastern coastal ecosystems should focus on the relative importance of different habitat types to these species’ foraging and nesting requirements. Our straightforward prioritization approach is applicable to other coastal systems and can provide insight to managers on which species to focus resources, what components of their habitats need to be protected, and which locations in the study area will provide habitat refuges in the face of SLR.

  13. Concurrent assessment of fish and habitat in warmwater streams in Wyoming

    Science.gov (United States)

    Quist, M.C.; Hubert, W.A.; Rahel, F.J.

    2006-01-01

    Fisheries research and management in North America have focused largely on sport fishes, but native non-game fishes have attracted increased attention due to their declines. The Warmwater Stream Assessment (WSA) was developed to evaluate simultaneously both fish and habitat in Wyoming streams by a process that includes three major components: (1) stream-reach selection and accumulation of existing information, (2) fish and habitat sampling and (3) summarisation and evaluation of fish and habitat information. Fish are sampled by electric fishing or seining and habitat is measured at reach and channel-unit (i.e. pool, run, riffle, side channel, or backwater) scales. Fish and habitat data are subsequently summarised using a data-matrix approach. Hierarchical decision trees are used to assess critical habitat requirements for each fish species expected or found in the reach. Combined measurements of available habitat and the ecology of individual species contribute to the evaluation of the observed fish assemblage. The WSA incorporates knowledge of the fish assemblage and habitat features to enable inferences of factors likely influencing both the fish assemblage and their habitat. The WSA was developed for warmwater streams in Wyoming, but its philosophy, process and conceptual basis may be applied to environmental assessments in other geographical areas. ?? 2006 Blackwell Publishing Ltd.

  14. Upland hardwood habitat types in southwestern North Dakota

    Science.gov (United States)

    Michele M. Girard; Harold Goetz; Ardell J. Bjugstad

    1985-01-01

    The Daubenmire habitat type method was used to classify the upland hardwood draws of southwestern North Dakota. Preliminary data analysis indicates there are four upland habitat types: Fraxinus pennsylvanica/Prunus virginiana; F. pnnseanica-Ulmus americana/P. virginiana; Populus...

  15. Green Turtle Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for green turtle as designated by Federal Register Vol. 63, No. 46701, September 2, 1998, Rules and Regulations.

  16. Right Whale Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for Right Whale as designated by Federal Register Vol. 59, No. 28805, May 19, 1993, Rules and Regulations.

  17. The relative effects of habitat loss, fragmentation, and degradation on population extinction

    Science.gov (United States)

    The most prominent conservation concerns are typically habitat loss and habitat fragmentation. The role of habitat degradation has received comparatively little attention. But research has shown that the quality of habitat patches can significantly influence wildlife population d...

  18. Variações anuais na produção de frutos e sementes de Castanheira-do-Brasil (Bertholletia excelsa Bonpl., Lecythidaceae em florestas nativas de Roraima

    Directory of Open Access Journals (Sweden)

    Helio Tonini

    2014-02-01

    Full Text Available Este trabalho foi desenvolvido com o objetivo de estudar as variações anuais na produção de frutos e sementes entre populações e indivíduos em castanhais nativos de Roraima. Os dados foram obtidos em cinco parcelas permanentes de 300 m x 300 m instaladas nos Municípios de Caracaraí e São João da Baliza. Nas parcelas permanentes, todas as castanheiras com diâmetro à altura do peito (DAP superior ou igual a 10 cm foram identificadas, medidas e numeradas através de placas de alumínio presas aos fustes por pregos. Durante o período de queda dos frutos (março a julho, as árvores foram visitadas em duas ocasiões no meio e no final desse período, e os frutos contados, abertos e pesados com balança de gancho digital com precisão de 50 g. A produção de frutos e sementes varia entre populações e indivíduos e a maioria não produz frutos todos os anos. No ano de maior produção, um castanhal chega a produzir 52 vezes mais do que em anos de baixa. Nos locais estudados, a produção total concentra-se em um pequeno número de indivíduos com um ano de pico de produção (mast-year.

  19. Deep Space Habitat Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Deep Space Habitat was closed out at the end of Fiscal Year 2013 (September 30, 2013). Results and select content have been incorporated into the new Exploration...

  20. Johnsons Seagrass Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for Johnson's Seagrass as designated by Federal Register Vol. 65, No. 66, Wednesday, April 5, 2000, Rules and Regulations.

  1. Prioritizing tiger conservation through landscape genetics and habitat linkages.

    Science.gov (United States)

    Yumnam, Bibek; Jhala, Yadvendradev V; Qureshi, Qamar; Maldonado, Jesus E; Gopal, Rajesh; Saini, Swati; Srinivas, Y; Fleischer, Robert C

    2014-01-01

    Even with global support for tiger (Panthera tigris) conservation their survival is threatened by poaching, habitat loss and isolation. Currently about 3,000 wild tigers persist in small fragmented populations within seven percent of their historic range. Identifying and securing habitat linkages that connect source populations for maintaining landscape-level gene flow is an important long-term conservation strategy for endangered carnivores. However, habitat corridors that link regional tiger populations are often lost to development projects due to lack of objective evidence on their importance. Here, we use individual based genetic analysis in combination with landscape permeability models to identify and prioritize movement corridors across seven tiger populations within the Central Indian Landscape. By using a panel of 11 microsatellites we identified 169 individual tigers from 587 scat and 17 tissue samples. We detected four genetic clusters within Central India with limited gene flow among three of them. Bayesian and likelihood analyses identified 17 tigers as having recent immigrant ancestry. Spatially explicit tiger occupancy obtained from extensive landscape-scale surveys across 76,913 km(2) of forest habitat was found to be only 21,290 km(2). After accounting for detection bias, the covariates that best explained tiger occupancy were large, remote, dense forest patches; large ungulate abundance, and low human footprint. We used tiger occupancy probability to parameterize habitat permeability for modeling habitat linkages using least-cost and circuit theory pathway analyses. Pairwise genetic differences (FST) between populations were better explained by modeled linkage costs (r>0.5, p<0.05) compared to Euclidean distances, which was in consonance with observed habitat fragmentation. The results of our study highlight that many corridors may still be functional as there is evidence of contemporary migration. Conservation efforts should provide legal status

  2. Prioritizing tiger conservation through landscape genetics and habitat linkages.

    Directory of Open Access Journals (Sweden)

    Bibek Yumnam

    Full Text Available Even with global support for tiger (Panthera tigris conservation their survival is threatened by poaching, habitat loss and isolation. Currently about 3,000 wild tigers persist in small fragmented populations within seven percent of their historic range. Identifying and securing habitat linkages that connect source populations for maintaining landscape-level gene flow is an important long-term conservation strategy for endangered carnivores. However, habitat corridors that link regional tiger populations are often lost to development projects due to lack of objective evidence on their importance. Here, we use individual based genetic analysis in combination with landscape permeability models to identify and prioritize movement corridors across seven tiger populations within the Central Indian Landscape. By using a panel of 11 microsatellites we identified 169 individual tigers from 587 scat and 17 tissue samples. We detected four genetic clusters within Central India with limited gene flow among three of them. Bayesian and likelihood analyses identified 17 tigers as having recent immigrant ancestry. Spatially explicit tiger occupancy obtained from extensive landscape-scale surveys across 76,913 km(2 of forest habitat was found to be only 21,290 km(2. After accounting for detection bias, the covariates that best explained tiger occupancy were large, remote, dense forest patches; large ungulate abundance, and low human footprint. We used tiger occupancy probability to parameterize habitat permeability for modeling habitat linkages using least-cost and circuit theory pathway analyses. Pairwise genetic differences (FST between populations were better explained by modeled linkage costs (r>0.5, p<0.05 compared to Euclidean distances, which was in consonance with observed habitat fragmentation. The results of our study highlight that many corridors may still be functional as there is evidence of contemporary migration. Conservation efforts should

  3. Structural habitat predicts functional dispersal habitat of a large carnivore: how leopards change spots.

    Science.gov (United States)

    Fattebert, Julien; Robinson, Hugh S; Balme, Guy; Slotow, Rob; Hunter, Luke

    2015-10-01

    Natal dispersal promotes inter-population linkage, and is key to spatial distribution of populations. Degradation of suitable landscape structures beyond the specific threshold of an individual's ability to disperse can therefore lead to disruption of functional landscape connectivity and impact metapopulation function. Because it ignores behavioral responses of individuals, structural connectivity is easier to assess than functional connectivity and is often used as a surrogate for landscape connectivity modeling. However using structural resource selection models as surrogate for modeling functional connectivity through dispersal could be erroneous. We tested how well a second-order resource selection function (RSF) models (structural connectivity), based on GPS telemetry data from resident adult leopard (Panthera pardus L.), could predict subadult habitat use during dispersal (functional connectivity). We created eight non-exclusive subsets of the subadult data based on differing definitions of dispersal to assess the predictive ability of our adult-based RSF model extrapolated over a broader landscape. Dispersing leopards used habitats in accordance with adult selection patterns, regardless of the definition of dispersal considered. We demonstrate that, for a wide-ranging apex carnivore, functional connectivity through natal dispersal corresponds to structural connectivity as modeled by a second-order RSF. Mapping of the adult-based habitat classes provides direct visualization of the potential linkages between populations, without the need to model paths between a priori starting and destination points. The use of such landscape scale RSFs may provide insight into predicting suitable dispersal habitat peninsulas in human-dominated landscapes where mitigation of human-wildlife conflict should be focused. We recommend the use of second-order RSFs for landscape conservation planning and propose a similar approach to the conservation of other wide-ranging large

  4. Habitat assessment of non-wadeable rivers in Michigan.

    Science.gov (United States)

    Wilhelm, Jennifer G O; Allan, J David; Wessell, Kelly J; Merritt, Richard W; Cummins, Kenneth W

    2005-10-01

    Habitat evaluation of wadeable streams based on accepted protocols provides a rapid and widely used adjunct to biological assessment. However, little effort has been devoted to habitat evaluation in non-wadeable rivers, where it is likely that protocols will differ and field logistics will be more challenging. We developed and tested a non-wadeable habitat index (NWHI) for rivers of Michigan, where non-wadeable rivers were defined as those of order >or=5, drainage area >or=1600 km2, mainstem lengths >or=100 km, and mean annual discharge >or=15 m3/s. This identified 22 candidate rivers that ranged in length from 103 to 825 km and in drainage area from 1620 to 16,860 km2. We measured 171 individual habitat variables over 2-km reaches at 35 locations on 14 rivers during 2000-2002, where mean wetted width was found to range from 32 to 185 m and mean thalweg depth from 0.8 to 8.3 m. We used correlation and principal components analysis to reduce the number of variables, and examined the spatial pattern of retained variables to exclude any that appeared to reflect spatial location rather than reach condition, resulting in 12 variables to be considered in the habitat index. The proposed NWHI included seven variables: riparian width, large woody debris, aquatic vegetation, bottom deposition, bank stability, thalweg substrate, and off-channel habitat. These variables were included because of their statistical association with independently derived measures of human disturbance in the riparian zone and the catchment, and because they are considered important in other habitat protocols or to the ecology of large rivers. Five variables were excluded because they were primarily related to river size rather than anthropogenic disturbance. This index correlated strongly with indices of disturbance based on the riparian (adjusted R2 = 0.62) and the catchment (adjusted R2 = 0.50), and distinguished the 35 river reaches into the categories of poor (2), fair (19), good (13), and

  5. Habitat Mapping Camera (HABCAM)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset entails imagery collected using the HabCam towed underwater vehicle and annotated data on objects or habitats in the images and notes on image...

  6. The role of macrophytes in habitat structuring in aquatic ecosystems: methods of measurement, causes and consequences on animal assemblages' composition and biodiversity O papel das macrófitas na estruturação de habitat em ambientes aquáticos: métodos de medida, causas e consequências para a composição das assembléias animais e biodiversidade

    Directory of Open Access Journals (Sweden)

    Sidinei Magela Thomaz

    2010-06-01

    structure and thus influence associated organisms. In this sense, they are suitable as the main focus of management strategies aimed at biodiversity restoration and conservation.Macrófitas aquáticas têm um importante papel na estruturação de comunidades em ambientes aquáticos. Essas plantas proporcionam estrutura física, aumentam a complexidade e a heterogeneidade de habitats e afetam vários grupos de organismos como invertebrados, peixes e aves aquáticas. A complexidade proporcionada pelas macrófitas tem sido exaustivamente estudada, porém, a mesma raramente tem sido medida de forma padronizada, dificultando comparações entre estudos e o estabelecimento de conclusões gerais. Com o objetivo de endereçar esse assunto, a presente revisão enfoca questões relacionadas à complexidade estrutural de habitats proporcionada por essas plantas e explora: i como a complexidade tem sido enfocada pelos ecólogos, com ênfase em estudos com macrófitas; ii os prós e contras de vários métodos usados para quantificar a complexidade; iii as consequências da estruturação de habitats proporcionada pelas macrófitas sobre invertebrados e peixes, assim como as possíveis causas, mediadas pela complexidade de habitats, que levam a alterações nas assembléias desses animais; iv os impactos potenciais de espécies exóticas invasoras de macrófitas sobre a complexidade de habitats e v a importância da estrutura fornecida por macrófitas em estratégias de manejo visando à conservação da biodiversidade. Nós examinamos a literatura produzida tanto em regiões temperadas como tropicais, mas priorizamos essa última. Os principais resultados dessa revisão são resumidos a seguir. Houve grande variedade de medidas da complexidade de habitats em macrófitas que visam compreender sua influência sobre as assembléias de animais associadas a essas plantas. No entanto, a falta de padronização (considerando uma extensa variação de técnicas e escalas de resolu

  7. Differential Habitat Use or Intraguild Interactions: What Structures a Carnivore Community?

    Directory of Open Access Journals (Sweden)

    Matthew E Gompper

    Full Text Available Differential habitat use and intraguild competition are both thought to be important drivers of animal population sizes and distributions. Habitat associations for individual species are well-established, and interactions between particular pairs of species have been highlighted in many focal studies. However, community-wide assessments of the relative strengths of these two factors have not been conducted. We built multi-scale habitat occupancy models for five carnivore taxa of New York's Adirondack landscape and assessed the relative performance of these models against ones in which co-occurrences of potentially competing carnivore species were also incorporated. Distribution models based on habitat performed well for all species. Black bear (Ursus americanus and fisher (Martes pennanti distribution was similar in that occupancy of both species was negatively associated with paved roads. However, black bears were also associated with larger forest fragments and fishers with smaller forest fragments. No models with habitat features were more supported than the null habitat model for raccoons (Procyon lotor. Martens (Martes americana were most associated with increased terrain ruggedness and elevation. Weasel (Mustela spp. occupancy increased with the cover of deciduous forest. For most species dyads habitat-only models were more supported than those models with potential competitors incorporated. The exception to this finding was for the smallest carnivore taxa (marten and weasel where habitat plus coyote abundance models typically performed better than habitat-only models. Assessing this carnivore community as whole, we conclude that differential habitat use is more important than species interactions in maintaining the distribution and structure of this carnivore guild.

  8. Enemy-free space and habitat-specific host specialization in a butterfly.

    Science.gov (United States)

    Wiklund, Christer; Friberg, Magne

    2008-08-01

    The majority of herbivorous insects have relatively specialized food habits. This suggests that specialization has some advantage(s) over generalization. Traditionally, feeding specialization has been thought to be linked to digestive or other food-related physiological advantages, but recent theory suggests that generalist natural enemies of herbivorous insects can also provide a major selective pressure for restricted host plant range. The European swallowtail butterfly Papilio machaon utilizes various plants in the Apiaceae family as hosts, but is an ecological specialist being monophagous on Angelica archangelica in southern Sweden. This perennial monocarp grows in three seaside habitat types: (1) on the barren rocky shore in the absence of any surrounding vegetation, (2) on the rocky shore with some surrounding vegetation, and (3) on species-rich meadows. The rocky shore habitat harbors few invertebrate generalist predators, whereas a number of invertebrate predators abound in the meadowland habitat. Here, we test the importance of enemy-free space for feeding specialization in Papilio machaon by assessing survival of larvae placed by hand on A. archangelica in each of the three habitat types, and by assessing the habitat-specificity of adult female egg-laying behavior by recording the distribution of eggs laid by free-flying adult females among the three habitat types. Larval survival was substantially higher in the rocky shore habitat than in the meadowland and significantly higher on host plants without surrounding vegetation on the rocky shore. Eggs laid by free-flying females were found in all three habitat types, but were significantly more frequent in the rocky shore habitat, suggesting that females prefer to lay eggs in the habitat type where offspring survival is highest. These results show that larval survivorship on the same host plant species can be strongly habitat-specific, and suggest that enemy-free space is an underlying factor that drives

  9. Using catenas for GIS-based mapping of NW Mediterranean littoral habitats

    Science.gov (United States)

    Mariani, Simone; Cefalì, Maria Elena; Terradas, Marc; Chappuis, Eglantine; Ballesteros, Enric

    2014-06-01

    Studies aimed at describing habitats and mapping their distributions are pivotal to implementing management plans and to effectively guide conservation measures. We developed a novel approach of data collection and entry (CAT-LIT) to establish a detailed cartography of the littoral habitats found along the Catalan coast (Spain). Field data were recorded using coded, two-digit hierarchical lists (e.g. Aa, Ab, etc.) of horizons found at each point along the coast, called catenas. The horizons were either dominated by species (on the rocky bottoms) or sediment types (on the beaches) and corresponded to LPRE, EUNIS and CORINE habitats. Catenas were transferred into a database and calculations about the extent of bottom types, habitats, and catenas themselves along the coast were carried out with GIS tools. In addition, habitat link richness was calculated and represented using network analysis programs. The application of CAT-LIT to the Catalan coast showed that the habitats dominated by the lichen Verrucaria amphibia and the flattened barnacle Euraphia depressa and those dominated by the barnacle Chthamalus spp. were almost ubiquitous. Those dominated by the red alga Corallina elongata, the mussel Mytilus galloprovincialis and the red alga Rissoella verruculosa were also common. Because of the frequency of their connections, those habitats formed a huge hub of links in the networks. By using catenas, the habitats can be viewed using GIS based programs keeping the catena as the main informational and ecological unit. The catenas allow maximum compactness when vertically distributed habitats are to be shown on a 2D map. The complete cartography and dataset on the spatial distribution of the littoral habitats from Catalonia is valuable for coastal management and conservation to study changes in the habitat distribution and relate such changes to anthropogenic pressures. Furthermore, the CAT-LIT can be easily adapted to shores of other seas and oceans to obtain accurate

  10. Yakima Habitat Improvement Project Master Plan, Technical Report 2003.

    Energy Technology Data Exchange (ETDEWEB)

    Golder Associates, Inc.

    2003-04-22

    The Yakima Urban Growth Area (UGA) is a developing and growing urban area in south-central Washington. Despite increased development, the Yakima River and its tributaries within the UGA continue to support threatened populations of summer steelhead and bull trout as well as a variety of non-listed salmonid species. In order to provide for the maintenance and recovery of these species, while successfully planning for the continued growth and development within the UGA, the City of Yakima has undertaken the Yakima Habitat Improvement Project. The overall goal of the project is to maintain, preserve, and restore functioning fish and wildlife habitat within and immediately surrounding the Yakima UGA over the long term. Acquisition and protection of the fish and wildlife habitat associated with key properties in the UGA will prevent future subdivision along riparian corridors, reduce further degradation or removal of riparian habitat, and maintain or enhance the long term condition of aquatic habitat. By placing these properties in long-term protection, the threat of development from continued growth in the urban area will be removed. To most effectively implement the multi-year habitat acquisition and protection effort, the City has developed this Master Plan. The Master Plan provides the structure and guidance for future habitat acquisition and restoration activities to be performed within the Yakima Urban Area. The development of this Master Plan also supports several Reasonable and Prudent Alternatives (RPAs) of the NOAA Fisheries 2000 Biological Opinion (BiOp), as well as the Water Investment Action Agenda for the Yakima Basin, local planning efforts, and the Columbia Basin Fish and Wildlife Authority's 2000 Fish and Wildlife Program. This Master Plan also provides the framework for coordination of the Yakima Habitat Improvement Project with other fish and wildlife habitat acquisition and protection activities currently being implemented in the area. As a

  11. Habitat selection of Tragulus napu and Tragulus javanicus using MaxEnt analysis

    Science.gov (United States)

    Taher, Taherah Mohd; Lihan, Tukimat; Mustapha, Muzzneena Ahmad; Nor, Shukor Mohd

    2018-04-01

    Large areas are converted into commercial land use such as agriculture and urban as a result from the increasing economic and population demand. This situation is largely affecting wildlife and its habitat. Malaysia as one of the largest oil palm-producing countries, should take precaution into conserving its forest and wildlife diversity. Although big mammal such as elephant and tiger are significant for wildlife diversity, medium and small mammals also contribute to the biological richness in Malaysia. This study aims to predict suitable habitat of medium mammal, Tragulus napu and Tragulus javanicus in the study area and identify its habitat characteristics. The method applied in this study uses maximum entropy (MaxEnt) modeling which utilized species distribution data and selected environmental variables to alienate potential habitat in the study area. The characteristic of the habitat was identified from the result of MaxEnt analysis. This method of habitat modeling shows different extent of predicted suitable habitat in the study area of both species in which Tragulus napu has a limited distribution compared to Tragulus javanicus. However, some characteristics are similar in both habitats. The knowledge on species habitat characteristics is important to predict wildlife habitat in order to make best decision on land use management and conservation.

  12. Habitat Evaluation Procedures (HEP) Report : Priest River, 2004-2005 Technical Report.

    Energy Technology Data Exchange (ETDEWEB)

    Entz, Ray

    2005-02-01

    On July 6, 2004, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the Priest River property, an acquisition completed by the Kalispel Tribe of Indians in 2001. Evaluation species and appropriate models include bald eagle, black-capped chickadee, Canada goose, mallard, yellow warbler, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The Priest River Project provides a total of 105.41 Habitat Units (HUs) for the species evaluated. Conifer forest habitat provides 26.95 HUs for bald eagle, black-capped chickadee, and white-tailed deer. Grassland habitat provides 23.78 HUs for Canada goose and mallard. Scmb-shrub vegetation provides 54.68 HUs for mallard, yellow warbler, and white-tailed deer.

  13. Habitat degradation affects the summer activity of polar bears.

    Science.gov (United States)

    Ware, Jasmine V; Rode, Karyn D; Bromaghin, Jeffrey F; Douglas, David C; Wilson, Ryan R; Regehr, Eric V; Amstrup, Steven C; Durner, George M; Pagano, Anthony M; Olson, Jay; Robbins, Charles T; Jansen, Heiko T

    2017-05-01

    Understanding behavioral responses of species to environmental change is critical to forecasting population-level effects. Although climate change is significantly impacting species' distributions, few studies have examined associated changes in behavior. Polar bear (Ursus maritimus) subpopulations have varied in their near-term responses to sea ice decline. We examined behavioral responses of two adjacent subpopulations to changes in habitat availability during the annual sea ice minimum using activity data. Location and activity sensor data collected from 1989 to 2014 for 202 adult female polar bears in the Southern Beaufort Sea (SB) and Chukchi Sea (CS) subpopulations were used to compare activity in three habitat types varying in prey availability: (1) land; (2) ice over shallow, biologically productive waters; and (3) ice over deeper, less productive waters. Bears varied activity across and within habitats with the highest activity at 50-75% sea ice concentration over shallow waters. On land, SB bears exhibited variable but relatively high activity associated with the use of subsistence-harvested bowhead whale carcasses, whereas CS bears exhibited low activity consistent with minimal feeding. Both subpopulations had fewer observations in their preferred shallow-water sea ice habitats in recent years, corresponding with declines in availability of this substrate. The substantially higher use of marginal habitats by SB bears is an additional mechanism potentially explaining why this subpopulation has experienced negative effects of sea ice loss compared to the still-productive CS subpopulation. Variability in activity among, and within, habitats suggests that bears alter their behavior in response to habitat conditions, presumably in an attempt to balance prey availability with energy costs.

  14. Defining geo-habitats for groundwater ecosystem assessments: an example from England and Wales (UK)

    Science.gov (United States)

    Weitowitz, Damiano C.; Maurice, Louise; Lewis, Melinda; Bloomfield, John P.; Reiss, Julia; Robertson, Anne L.

    2017-12-01

    Groundwater ecosystems comprising micro-organisms and metazoans provide an important contribution to global biodiversity. Their complexity depends on geology, which determines the physical habitat available, and the chemical conditions within it. Despite this, methods of classifying groundwater habitats using geological data are not well established and researchers have called for higher resolution habitat frameworks. A novel habitat typology for England and Wales (UK) is proposed, which distinguishes 11 geological habitats (geo-habitats) on hydrogeological principles and maps their distribution. Hydrogeological and hydrochemical data are used to determine the characteristics of each geo-habitat, and demonstrate their differences. Using these abiotic parameters, a new method to determine abiotic habitat quality is then developed. The geo-habitats had significantly different characteristics, validating the classification system. All geo-habitats were highly heterogeneous, containing both high quality habitat patches that are likely to be suitable for fauna, and areas of low quality that may limit faunal distributions. Karstic and porous habitats generally were higher quality than fractured habitats. Overall, 70% of England and Wales are covered by lower quality fractured habitats, with only 13% covered by higher quality habitats. The main areas of high quality habitats occur in central England as north-south trending belts, possibly facilitating dispersal along this axis. They are separated by low quality geo-habitats that may prevent east-west dispersal of fauna. In south-west England and Wales suitable geo-habitats occur as small isolated patches. Overall, this paper provides a new national-scale typology that is adaptable for studies in other geographic areas.

  15. Population status, distribution and habitat association of waterbuck ...

    African Journals Online (AJOL)

    As part of ecological studies of larger mammals in Chebera Churchura National Park, southwestern Ethiopia, population, distribution and habitat association of the waterbuck, Kobus ellipsiprymnus ellipsiprymnus were studied during wet and dry seasons of 2013–2014. Representative transects across the main habitat types ...

  16. Weather conditions drive dynamic habitat selection in a generalist predator

    DEFF Research Database (Denmark)

    Sunde, Peter; Thorup, Kasper; Jacobsen, Lars B.

    2014-01-01

    Despite the dynamic nature of habitat selection, temporal variation as arising from factors such as weather are rarely quantified in species-habitat relationships. We analysed habitat use and selection (use/availability) of foraging, radio-tagged little owls (Athene noctua), a nocturnal, year...... and quadratic effects of temperature. Even when controlling for the temporal context, both land cover types were used more evenly than predicted from variation in availability (functional response in habitat selection). Use of two other land cover categories (pastures and moist areas) increased linearly...... with temperature and was proportional to their availability. The study shows that habitat selection by generalist foragers may be highly dependent on temporal variables such as weather, probably because such foragers switch between weather dependent feeding opportunities offered by different land cover types...

  17. Innovative study methods for the Mediterranean coralligenous habitats

    Directory of Open Access Journals (Sweden)

    P.A. Zapata-Ramírez

    2013-11-01

    Full Text Available Coralligenous habitats are of special interest in the Mediterranean Sea because they represent one of the most important biodiversity ‘hot-spots’ and are considered of great relevance for fisheries activities in the region. Despite their importance, however, there are missing consensual methodologies for their monitoring and, despite some attempts, no environmental or ecological quality indices have been established yet. This situation could be related to the difficulties associated with their exploration and their spatial heterogeneity. These habitats are in urgent need of efficient standard monitoring and management protocols programmes to develop an effective network for their conservation. Here we reviewed the available methodologies and robotics tools used to evaluate and monitor benthic habitats, highlighting the importance of defining rapid cost-effective sampling and analyses approaches and architectures for future monitoring of changes in coralligenous habitats based on current technological developments. We identified still images acquisitions as the most effective data gathering system. Stereo photogrammetry, photomosaic elaboration and three-dimensional (3D modelling may largely improve the data analysis and therefore the quality status assessment of the coralligenous habitats. The advantage and efficiency of different approaches and methods, and whether they should be applied and standardised for further monitoring activities, were discussed.

  18. Our use, misuse, and abandonment of a concept: Whither habitat?

    Science.gov (United States)

    Kirk, David Anthony; Park, Allysia C; Smith, Adam C; Howes, Briar J; Prouse, Brigid K; Kyssa, Naschelly G; Fairhurst, Elizabeth N; Prior, Kent A

    2018-04-01

    The foundational concept of habitat lies at the very root of the entire science of ecology, but inaccurate use of the term compromises scientific rigor and communication among scientists and nonscientists. In 1997, Hall, Krausman & Morrison showed that 'habitat' was used correctly in only 55% of articles. We ask whether use of the term has been more accurate since their plea for standardization and whether use varies across the broader range of journals and taxa in the contemporary literature (1998-2012). We searched contemporary literature for 'habitat' and habitat-related terms, ranking usage as either correct or incorrect, following a simplified version of Hall et al.'s definitions. We used generalized linear models to compare use of the term in contemporary literature with the papers reviewed by Hall et al. and to test the effects of taxa, journal impact in the contemporary articles and effects due to authors that cited Hall et al. Use of the term 'habitat' has not improved; it was still only used correctly about 55% of the time in the contemporary data. Proportionately more correct uses occurred in articles that focused on animals compared to ones that included plants, and papers that cited Hall et al. did use the term correctly more often. However, journal impact had no effect. Some habitat terms are more likely to be misused than others, notably 'habitat type', usually used to refer to vegetation type, and 'suitable habitat' or 'unsuitable habitat', which are either redundant or nonsensical by definition. Inaccurate and inconsistent use of the term can lead to (1) misinterpretation of scientific findings; (2) inefficient use of conservation resources; (3) ineffective identification and prioritization of protected areas; (4) limited comparability among studies; and (5) miscommunication of science-based findings. Correct usage would improve communication with scientists and nonscientists, thereby benefiting conservation efforts, and ecology as a science.

  19. Diversity and Community Composition of Vertebrates in Desert River Habitats

    Science.gov (United States)

    Free, C. L.; Baxter, G. S.; Dickman, C. R.; Lisle, A.; Leung, L. K.-P.

    2015-01-01

    Animal species are seldom distributed evenly at either local or larger spatial scales, and instead tend to aggregate in sites that meet their resource requirements and maximise fitness. This tendency is likely to be especially marked in arid regions where species could be expected to concentrate at resource-rich oases. In this study, we first test the hypothesis that productive riparian sites in arid Australia support higher vertebrate diversity than other desert habitats, and then elucidate the habitats selected by different species. We addressed the first aim by examining the diversity and composition of vertebrate assemblages inhabiting the Field River and adjacent sand dunes in the Simpson Desert, western Queensland, over a period of two and a half years. The second aim was addressed by examining species composition in riparian and sand dune habitats in dry and wet years. Vertebrate species richness was estimated to be highest (54 species) in the riverine habitats and lowest on the surrounding dune habitats (45 species). The riverine habitats had different species pools compared to the dune habitats. Several species, including the agamid Gowidon longirostris and tree frog Litoria rubella, inhabited the riverine habitats exclusively, while others such as the skinks Ctenotus ariadnae and C. dux were captured only in the dune habitats. The results suggest that, on a local scale, diversity is higher along riparian corridors and that riparian woodland is important for tree-dependent species. Further, the distribution of some species, such as Mus musculus, may be governed by environmental variables (e.g. soil moisture) associated with riparian corridors that are not available in the surrounding desert environment. We conclude that inland river systems may be often of high conservation value, and that management should be initiated where possible to alleviate threats to their continued functioning. PMID:26637127

  20. Habitat Evaluation Procedures (HEP) Report : West Beaver Lake, 2004-2005 Technical Report.

    Energy Technology Data Exchange (ETDEWEB)

    Entz, Ray

    2005-02-01

    On September 7, 2004, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the West Beaver Lake property, an acquisition completed by the Kalispel Tribe of Indians in September 2004. Evaluation species and appropriate models include bald eagle, black-capped chickadee, mallard, muskrat, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The West Beaver Lake Project provides a total of 103.08 Habitat Units (HUs) for the species evaluated. Emergent wetland habitat provides 7.17 HUs for mallard and muskrat. Conifer forest habitat provides 95.91 HUs for bald eagle, black-capped chickadee, mallard, and white-tailed deer. The objective of using HEP at the West Beaver Lake Project and other protected properties is to document the quality and quantity of available habitat for selected wildlife species. In this way, HEP provides information on the relative value of the same area at future points in time so that the effect of management activities on wildlife habitat can be quantified. When combined with other tools, the baseline HEP will be used to determine the most effective on-site management, restoration, and enhancement actions to increase habitat suitability for targeted species. The same process will be replicated every five years to quantitatively evaluate the effectiveness of management strategies in improving and maintaining habitat conditions while providing additional crediting to BPA for enhanced habitat values.

  1. Global habitat preferences of commercially valuable tuna

    KAUST Repository

    Arrizabalaga, Haritz; Dufour, Florence; Kell, Laurence T.; Merino, Gorka; Ibaibarriaga, Leire; Chust, Guillem; Irigoien, Xabier; Santiago, Josu; Murua, Hilario; Fraile, Igaratza; Chifflet, Marina; Goikoetxea, Nerea; Sagarminaga, Yolanda; Aumont, Olivier; Bopp, Laurent; Herrera, Miguel Angel; Marc Fromentin, Jean; Bonhomeau, Sylvain

    2015-01-01

    In spite of its pivotal role in future implementations of the Ecosystem Approach to Fisheries Management, current knowledge about tuna habitat preferences remains fragmented and heterogeneous, because it relies mainly on regional or local studies that have used a variety of approaches making them difficult to combine. Therefore in this study we analyse data from six tuna species in the Pacific, Atlantic and Indian Oceans in order to provide a global, comparative perspective of habitat preferences. These data are longline catch per unit effort from 1958 to 2007 for albacore, Atlantic bluefin, southern bluefin, bigeye, yellowfin and skipjack tunas. Both quotient analysis and Generalised Additive Models were used to determine habitat preference with respect to eight biotic and abiotic variables. Results confirmed that, compared to temperate tunas, tropical tunas prefer warm, anoxic, stratified waters. Atlantic and southern bluefin tuna prefer higher concentrations of chlorophyll than the rest. The two species also tolerate most extreme sea surface height anomalies and highest mixed layer depths. In general, Atlantic bluefin tuna tolerates the widest range of environmental conditions. An assessment of the most important variables determining fish habitat is also provided. © 2014 Elsevier Ltd.

  2. Global habitat preferences of commercially valuable tuna

    KAUST Repository

    Arrizabalaga, Haritz

    2015-03-01

    In spite of its pivotal role in future implementations of the Ecosystem Approach to Fisheries Management, current knowledge about tuna habitat preferences remains fragmented and heterogeneous, because it relies mainly on regional or local studies that have used a variety of approaches making them difficult to combine. Therefore in this study we analyse data from six tuna species in the Pacific, Atlantic and Indian Oceans in order to provide a global, comparative perspective of habitat preferences. These data are longline catch per unit effort from 1958 to 2007 for albacore, Atlantic bluefin, southern bluefin, bigeye, yellowfin and skipjack tunas. Both quotient analysis and Generalised Additive Models were used to determine habitat preference with respect to eight biotic and abiotic variables. Results confirmed that, compared to temperate tunas, tropical tunas prefer warm, anoxic, stratified waters. Atlantic and southern bluefin tuna prefer higher concentrations of chlorophyll than the rest. The two species also tolerate most extreme sea surface height anomalies and highest mixed layer depths. In general, Atlantic bluefin tuna tolerates the widest range of environmental conditions. An assessment of the most important variables determining fish habitat is also provided. © 2014 Elsevier Ltd.

  3. ANALYZE THE IMPACT OF HABITAT PATCHES ON WILDLIFE ROAD-KILL

    Directory of Open Access Journals (Sweden)

    S. Seok

    2015-10-01

    Full Text Available The ecosystem fragmentation due to transportation infrastructure causes a road-kill phenomenon. When making policies for mitigating road-kill it is important to select target-species in order to enhance its efficiency. However, many wildlife crossing structures have been questioned regarding their effectiveness due to lack of considerations such as target-species selection, site selection, management, etc. The purpose of this study is to analyse the impact of habitat patches on wildlife road-kill and to suggest that spatial location of habitat patches should be considered as one of the important factors when making policies for mitigating road-kill. Habitat patches were presumed from habitat variables and a suitability index on target-species that was chosen by literature review. The road-kill hotspot was calculated using Getis-Ord Gi*. After that, we performed a correlation analysis between Gi Z-score and the distance from habitat patches to the roads. As a result, there is a low negative correlation between two variables and it increases the Gi Z-score if the habitat patches and the roads become closer.

  4. Analyze the Impact of Habitat Patches on Wildlife Road-Kill

    Science.gov (United States)

    Seok, S.; Lee, J.

    2015-10-01

    The ecosystem fragmentation due to transportation infrastructure causes a road-kill phenomenon. When making policies for mitigating road-kill it is important to select target-species in order to enhance its efficiency. However, many wildlife crossing structures have been questioned regarding their effectiveness due to lack of considerations such as target-species selection, site selection, management, etc. The purpose of this study is to analyse the impact of habitat patches on wildlife road-kill and to suggest that spatial location of habitat patches should be considered as one of the important factors when making policies for mitigating road-kill. Habitat patches were presumed from habitat variables and a suitability index on target-species that was chosen by literature review. The road-kill hotspot was calculated using Getis-Ord Gi*. After that, we performed a correlation analysis between Gi Z-score and the distance from habitat patches to the roads. As a result, there is a low negative correlation between two variables and it increases the Gi Z-score if the habitat patches and the roads become closer.

  5. Análise Empírica dos Impactos dos Accruals na Variação do Capital Circulante Líquido: um estudo no setor de siderurgia e metalurgia

    Directory of Open Access Journals (Sweden)

    Romualdo Douglas Colauto

    2009-10-01

    Full Text Available O artigo demonstra os impactos dos accruals na variação do capital circulante líquido em companhias abertas do setor de siderurgia e metalurgia. Para constatação de evidências empíricas, utilizou-se como população-alvo as Sociedades Anônimas Abertas apresentadas entre as 500 Maiores e Melhores Empresas, segundo critério da Revista Exame na edição de 2003. A amostra extraída da população foi do tipo intencional não probabilística, com 7 empresas representativas do setor de Siderurgia e Metalurgia. O estudo é delineado como descritivo utilizando-se as técnicas de cluster e intervalo interpercentil para categorizar os dados necessários para as inferências. Os resultados ajudam a melhorar qualidade da informação contábil ao mostrar que os accruals provocam alterações no resultado do período, mas não infl uenciam, simultaneamente, o fluxo financeiro das atividades operacionais das empresas. Coefi cientes de correlações entre o resultado contábil do período ajustado pelos accruals e a variação do capital circulante líquido não apresentaram homogeneidade nos setores observados, mas denotaram significância estatística.

  6. Architecture and life support systems for a rotating space habitat

    Science.gov (United States)

    Misra, Gaurav

    Life Support Systems are critical to sustain human habitation of space over long time periods. As orbiting space habitats become operational in the future, support systems such as atmo-sphere, food, water etc. will play a very pivotal role in sustaining life. To design a long-duration space habitat, it's important to consider the full gamut of human experience of the environment. Long-term viability depends on much more than just the structural or life support efficiency. A space habitat isn't just a machine; it's a life experience. To be viable, it needs to keep the inhabitants satisfied with their condition. This paper provides conceptual research on several key factors that influence the growth and sustainability of humans in a space habitat. Apart from the main life support system parameters, the architecture (both interior and exterior) of the habitat will play a crucial role in influencing the liveability in the space habitat. In order to ensure the best possible liveability for the inhabitants, a truncated (half cut) torus is proposed as the shape of the habitat. This structure rotating at an optimum rpm will en-sure 1g pseudo gravity to the inhabitants. The truncated torus design has several advantages over other proposed shapes such as a cylinder or a sphere. The design provides minimal grav-ity variation (delta g) in the living area, since its flat outer pole ensures a constant gravity. The design is superior in economy of structural and atmospheric mass. Interior architecture of the habitat addresses the total built environment, drawing from diverse disciplines includ-ing physiology, psychology, and sociology. Furthermore, factors such as line of sight, natural sunlight and overhead clearance have been discussed in the interior architecture. Substantial radiation shielding is also required in order to prevent harmful cosmic radiations and solar flares from causing damage to inhabitants. Regolith shielding of 10 tons per meter square is proposed for the

  7. Habitat-based constraints on food web structure and parasite life cycles.

    Science.gov (United States)

    Rossiter, Wayne; Sukhdeo, Michael V K

    2014-04-01

    Habitat is frequently implicated as a powerful determinant of community structure and species distributions, but few studies explicitly evaluate the relationship between habitat-based patterns of species' distributions and the presence or absence of trophic interactions. The complex (multi-host) life cycles of parasites are directly affected by these factors, but almost no data exist on the role of habitat in constraining parasite-host interactions at the community level. In this study the relationship(s) between species abundances, distributions and trophic interactions (including parasitism) were evaluated in the context of habitat structure (classic geomorphic designations of pools, riffles and runs) in a riverine community (Raritan River, Hunterdon County, NJ, USA). We report 121 taxa collected over a 2-year period, and compare the observed food web patterns to null model expectations. The results show that top predators are constrained to particular habitat types, and that species' distributions are biased towards pool habitats. However, our null model (which incorporates cascade model assumptions) accurately predicts the observed patterns of trophic interactions. Thus, habitat strongly dictates species distributions, and patterns of trophic interactions arise as a consequence of these distributions. Additionally, we find that hosts utilized in parasite life cycles are more overlapping in their distributions, and this pattern is more pronounced among those involved in trophic transmission. We conclude that habitat structure may be a strong predictor of parasite transmission routes, particularly within communities that occupy heterogeneous habitats.

  8. Influence of habitat on behavior of Towndsend's ground squirrels (Spermophilus townsendii)

    Science.gov (United States)

    Sharpe, Peter B.; Van Horne, Beatrice

    1998-01-01

    Trade-offs between foraging and predator avoidance may affect an animal's survival and reproduction. These trade-offs may be influenced by differences in vegetative cover, especially if foraging profitability and predation risk differ among habitats. We examined above-ground activity of Townsend's ground squirrels (Spermophilus townsendii) in four habitats in the Snake River Birds of Prey National Conservation Area in southwestern Idaho to determine if behavior of ground squirrels varied among habitats, and we assessed factors that might affect perceived predation risk (i. e. predator detectability, predation pressure, population density). The proportion of time spent in vigilance by ground squirrels in winterfat (Krascheninnikovia lanata) and mosaic habitats of winterfat-sagebrush (Artemisia tridentata) was more than twice that of ground squirrels in burned and unburned sagebrush habitats. We found no evidence for the 'many-eyes' hypothesis as an explanation for differences in vigilance among habitats. Instead, environmental heterogeneity, especially vegetation structure, likely influenced activity budgets of ground squirrels. Differences in vigilance may have been caused by differences in predator detectability and refuge availability, because ground squirrels in the winterfat and mosaic habitats also spent more time in upright vigilant postures than ground squirrels in burned-sagebrush or sagebrush habitats. Such postures may enhance predator detection in low-growing winterfat.

  9. The importance of ambient sound level to characterise anuran habitat.

    Directory of Open Access Journals (Sweden)

    Sandra Goutte

    Full Text Available Habitat characterisation is a pivotal step of any animal ecology study. The choice of variables used to describe habitats is crucial and need to be relevant to the ecology and behaviour of the species, in order to reflect biologically meaningful distribution patterns. In many species, acoustic communication is critical to individuals' interactions, and it is expected that ambient acoustic conditions impact their local distribution. Yet, classic animal ecology rarely integrates an acoustic dimension in habitat descriptions. Here we show that ambient sound pressure level (SPL is a strong predictor of calling site selection in acoustically active frog species. In comparison to six other habitat-related variables (i.e. air and water temperature, depth, width and slope of the stream, substrate, SPL had the most important explanatory power in microhabitat selection for the 34 sampled species. Ambient noise was particularly useful in differentiating two stream-associated guilds: torrents and calmer streams dwelling species. Guild definitions were strongly supported by SPL, whereas slope, which is commonly used in stream-associated habitat, had a weak explanatory power. Moreover, slope measures are non-standardized across studies and are difficult to assess at small scale. We argue that including an acoustic descriptor will improve habitat-species analyses for many acoustically active taxa. SPL integrates habitat topology and temporal information (such as weather and hour of the day, for example and is a simple and precise measure. We suggest that habitat description in animal ecology should include an acoustic measure such as noise level because it may explain previously misunderstood distribution patterns.

  10. Shallow-water habitats as sources of fallback foods for hominins.

    Science.gov (United States)

    Wrangham, Richard; Cheney, Dorothy; Seyfarth, Robert; Sarmiento, Esteban

    2009-12-01

    Underground storage organs (USOs) have been proposed as critical fallback foods for early hominins in savanna, but there has been little discussion as to which habitats would have been important sources of USOs. USOs consumed by hominins could have included both underwater and underground storage organs, i.e., from both aquatic and terrestrial habitats. Shallow aquatic habitats tend to offer high plant growth rates, high USO densities, and relatively continuous USO availability throughout the year. Baboons in the Okavango delta use aquatic USOs as a fallback food, and aquatic or semiaquatic USOs support high-density human populations in various parts of the world. As expected given fossilization requisites, the African early- to mid-Pleistocene shows an association of Homo and Paranthropus fossils with shallow-water and flooded habitats where high densities of plant-bearing USOs are likely to have occurred. Given that early hominins in the tropics lived in relatively dry habitats, while others occupied temperate latitudes, ripe, fleshy fruits of the type preferred by African apes would not normally have been available year round. We therefore suggest that water-associated USOs were likely to have been key fallback foods, and that dry-season access to aquatic habitats would have been an important predictor of hominin home range quality. This study differs from traditional savanna chimpanzee models of hominin origins by proposing that access to aquatic habitats was a necessary condition for adaptation to savanna habitats. It also raises the possibility that harvesting efficiency in shallow water promoted adaptations for habitual bipedality in early hominins.

  11. Habitat Evaluation Procedures Report; Carl Property - Yakama Nation.

    Energy Technology Data Exchange (ETDEWEB)

    Ashley, Paul; Muse, Anthony

    2008-02-01

    A baseline habitat evaluation procedures (HEP) analysis was conducted on the Carl property (160 acres) in June 2007 to determine the number of habitat units to credit Bonneville Power Administration (BPA) for providing funds to acquire the property as partial mitigation for habitat losses associated with construction of McNary Dam. HEP surveys also helped assess the general ecological condition of the property. The Carl property appeared damaged from livestock grazing and exhibited a high percentage of invasive forbs. Exotic grasses, while present, did not comprise a large percentage of the available cover in most areas. Cover types were primarily grassland/shrubsteppe with a limited emergent vegetation component. Baseline HEP surveys generated 356.11 HUs or 2.2 HUs per acre. Habitat units were associated with the following HEP models: California quail (47.69 HUs), western meadowlark (114.78 HUs), mallard (131.93 HUs), Canada goose (60.34 HUs), and mink (1.38 HUs).

  12. Dormaier and Chester Butte 2007 Follow-up Habitat Evaluation Procedures Report.

    Energy Technology Data Exchange (ETDEWEB)

    Ashley, Paul R.

    2008-01-01

    Follow-up habitat evaluation procedures (HEP) analyses were conducted on the Dormaier and Chester Butte wildlife mitigation sites in April 2007 to determine the number of additional habitat units to credit Bonneville Power Administration (BPA) for providing funds to enhance, and maintain the project sites as partial mitigation for habitat losses associated with construction of Grand Coulee Dam. The Dormaier follow-up HEP survey generated 482.92 habitat units (HU) or 1.51 HUs per acre for an increase of 34.92 HUs over baseline credits. Likewise, 2,949.06 HUs (1.45 HUs/acre) were generated from the Chester Butte follow-up HEP analysis for an increase of 1,511.29 habitat units above baseline survey results. Combined, BPA will be credited with an additional 1,546.21 follow-up habitat units from the Dormaier and Chester Butte parcels.

  13. Habitat degradation and loss as key drivers of regional population extinction

    Science.gov (United States)

    Habitat quality is a fundamental driver of species distributions and population outcomes but is often difficult to measure. Further, habitat quality can be abstract, multi-faceted and challenging to compare alongside measures of habitat amount and fragmentation. Consequently, hab...

  14. Habitat stability and occurrences of malaria vector larvae in western Kenya highlands

    Directory of Open Access Journals (Sweden)

    Atieli Harrysone

    2009-10-01

    Full Text Available Abstract Background Although the occurrence of malaria vector larvae in the valleys of western Kenya highlands is well documented, knowledge of larval habitats in the uphill sites is lacking. Given that most inhabitants of the highlands actually dwell in the uphill regions, it is important to develop understanding of mosquito breeding habitat stability in these sites in order to determine their potential for larval control. Methods A total of 128 potential larval habitats were identified in hilltops and along the seasonal streams in the Sigalagala area of Kakamega district, western Kenya. Water availability in the habitats was followed up daily from August 3, 2006 to February 23, 2007. A habitat is defined as stable when it remains aquatic continuously for at least 12 d. Mosquito larvae were observed weekly. Frequencies of aquatic, stable and larvae positive habitats were compared between the hilltop and seasonal stream area using χ2-test. Factors affecting the presence/absence of Anopheles gambiae larvae in the highlands were determined using multiple logistic regression analysis. Results Topography significantly affected habitat availability and stability. The occurrence of aquatic habitats in the hilltop was more sporadic than in the stream area. The percentage of habitat occurrences that were classified as stable during the rainy season is 48.76% and 80.79% respectively for the hilltop and stream area. Corresponding frequencies of larvae positive habitats were 0% in the hilltop and 5.91% in the stream area. After the rainy season, only 23.42% of habitat occurrences were stable and 0.01% larvae positive habitats were found in the hilltops, whereas 89.75% of occurrences remained stable in the stream area resulting in a frequency of 12.21% larvae positive habitats. The logistic regression analysis confirmed the association between habitat stability and larval occurrence and indicated that habitat surface area was negatively affecting the

  15. Naturalization of European plants on other continents: The role of donor habitats.

    Science.gov (United States)

    Kalusová, Veronika; Chytrý, Milan; van Kleunen, Mark; Mucina, Ladislav; Dawson, Wayne; Essl, Franz; Kreft, Holger; Pergl, Jan; Weigelt, Patrick; Winter, Marten; Pyšek, Petr

    2017-12-26

    The success of European plant species as aliens worldwide is thought to reflect their association with human-disturbed environments. However, an explicit test including all human-made, seminatural and natural habitat types of Europe, and their contributions as donor habitats of naturalized species to the rest of the globe, has been missing. Here we combine two databases, the European Vegetation Checklist and the Global Naturalized Alien Flora, to assess how human influence in European habitats affects the probability of naturalization of their plant species on other continents. A total of 9,875 native European vascular plant species were assigned to 39 European habitat types; of these, 2,550 species have become naturalized somewhere in the world. Species that occur in both human-made habitats and seminatural or natural habitats in Europe have the highest probability of naturalization (64.7% and 64.5% of them have naturalized). Species associated only with human-made or seminatural habitats still have a significantly higher probability of becoming naturalized (41.7% and 28.6%, respectively) than species confined to natural habitats (19.4%). Species associated with arable land and human settlements were recorded as naturalized in the largest number of regions worldwide. Our findings highlight that plant species' association with native-range habitats disturbed by human activities, combined with broad habitat range, play an important role in shaping global patterns of plant invasions.

  16. Modeling habitat split: landscape and life history traits determine amphibian extinction thresholds.

    Directory of Open Access Journals (Sweden)

    Carlos Roberto Fonseca

    Full Text Available Habitat split is a major force behind the worldwide decline of amphibian populations, causing community change in richness and species composition. In fragmented landscapes, natural remnants, the terrestrial habitat of the adults, are frequently separated from streams, the aquatic habitat of the larvae. An important question is how this landscape configuration affects population levels and if it can drive species to extinction locally. Here, we put forward the first theoretical model on habitat split which is particularly concerned on how split distance - the distance between the two required habitats - affects population size and persistence in isolated fragments. Our diffusive model shows that habitat split alone is able to generate extinction thresholds. Fragments occurring between the aquatic habitat and a given critical split distance are expected to hold viable populations, while fragments located farther away are expected to be unoccupied. Species with higher reproductive success and higher diffusion rate of post-metamorphic youngs are expected to have farther critical split distances. Furthermore, the model indicates that negative effects of habitat split are poorly compensated by positive effects of fragment size. The habitat split model improves our understanding about spatially structured populations and has relevant implications for landscape design for conservation. It puts on a firm theoretical basis the relation between habitat split and the decline of amphibian populations.

  17. Modeling habitat split: landscape and life history traits determine amphibian extinction thresholds.

    Science.gov (United States)

    Fonseca, Carlos Roberto; Coutinho, Renato M; Azevedo, Franciane; Berbert, Juliana M; Corso, Gilberto; Kraenkel, Roberto A

    2013-01-01

    Habitat split is a major force behind the worldwide decline of amphibian populations, causing community change in richness and species composition. In fragmented landscapes, natural remnants, the terrestrial habitat of the adults, are frequently separated from streams, the aquatic habitat of the larvae. An important question is how this landscape configuration affects population levels and if it can drive species to extinction locally. Here, we put forward the first theoretical model on habitat split which is particularly concerned on how split distance - the distance between the two required habitats - affects population size and persistence in isolated fragments. Our diffusive model shows that habitat split alone is able to generate extinction thresholds. Fragments occurring between the aquatic habitat and a given critical split distance are expected to hold viable populations, while fragments located farther away are expected to be unoccupied. Species with higher reproductive success and higher diffusion rate of post-metamorphic youngs are expected to have farther critical split distances. Furthermore, the model indicates that negative effects of habitat split are poorly compensated by positive effects of fragment size. The habitat split model improves our understanding about spatially structured populations and has relevant implications for landscape design for conservation. It puts on a firm theoretical basis the relation between habitat split and the decline of amphibian populations.

  18. Defining critical habitats of threatened and endemic reef fishes with a multivariate approach.

    Science.gov (United States)

    Purcell, Steven W; Clarke, K Robert; Rushworth, Kelvin; Dalton, Steven J

    2014-12-01

    Understanding critical habitats of threatened and endemic animals is essential for mitigating extinction risks, developing recovery plans, and siting reserves, but assessment methods are generally lacking. We evaluated critical habitats of 8 threatened or endemic fish species on coral and rocky reefs of subtropical eastern Australia, by measuring physical and substratum-type variables of habitats at fish sightings. We used nonmetric and metric multidimensional scaling (nMDS, mMDS), Analysis of similarities (ANOSIM), similarity percentages analysis (SIMPER), permutational analysis of multivariate dispersions (PERMDISP), and other multivariate tools to distinguish critical habitats. Niche breadth was widest for 2 endemic wrasses, and reef inclination was important for several species, often found in relatively deep microhabitats. Critical habitats of mainland reef species included small caves or habitat-forming hosts such as gorgonian corals and black coral trees. Hard corals appeared important for reef fishes at Lord Howe Island, and red algae for mainland reef fishes. A wide range of habitat variables are required to assess critical habitats owing to varied affinities of species to different habitat features. We advocate assessments of critical habitats matched to the spatial scale used by the animals and a combination of multivariate methods. Our multivariate approach furnishes a general template for assessing the critical habitats of species, understanding how these vary among species, and determining differences in the degree of habitat specificity. © 2014 Society for Conservation Biology.

  19. Habitat Evaluation Procedures (HEP) Report; West Beaver Lake Project, Technical Report 2005

    Energy Technology Data Exchange (ETDEWEB)

    Entz, Ray

    2005-05-01

    On September 7, 2004, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the West Beaver Lake property, an acquisition completed by the Kalispel Tribe of Indians in September 2004. Evaluation species and appropriate models include bald eagle, black-capped chickadee, mallard, muskrat, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The West Beaver Lake Project provides a total of 82.69 Habitat Units (HUs) for the species evaluated. Emergent wetland habitat provides 8.80 HUs for mallard, muskrat, and Canada goose. Conifer forest habitat provides 70.33 HUs for bald eagle, black-capped chickadee, mallard, and white-tailed deer. Open water provides 3.30 HUs for mallard, muskrat, and Canada goose. The objective of using HEP at the West Beaver Lake Project and other protected properties is to document the quality and quantity of available habitat for selected wildlife species. In this way, HEP provides information on the relative value of the same area at future points in time so that the effect of management activities on wildlife habitat can be quantified. When combined with other tools, the baseline HEP will be used to determine the most effective on-site management, restoration, and enhancement actions to increase habitat suitability for targeted species. The same process will be replicated every five years to quantitatively evaluate the effectiveness of management strategies in improving and maintaining habitat conditions while providing additional crediting to BPA for enhanced habitat values.

  20. Information needs for habitat protection: Marbled murrelet habitat identification. Restoration project 93051b. Exxon Valdez oil spill restoration project final report

    Energy Technology Data Exchange (ETDEWEB)

    Kuletz, K.J.; Marks, D.K.; Naslund, N.L.; Goodson, N.G.; Cody, M.B.

    1994-12-01

    To define murrelet nesting habitat in southcentral Alaska, we surveyed inland activity of murrelets and measured habitat features between 1991 and 1993, in Prince William Sound, Kenai Fjords National Park and Afognak Island, Alaska (N=262 sites). Using all study areas, we developed statistical models that explain variation in murrelet activity levels and predict the occurrence of behaviors indicative of nesting, based on temporal, geographic, topographic, weather and habitat variables. The multiple regression analyses explained 52 percent of the variation in murrelet activity level. Stepwise logistic regression was used to identify variables that could predict the occurrence of nesting behaviors. The best model included survey method (from a boat, shore or inland), location relative to the head of a bay, tree diameter and number of potential nesting platforms on trees. Overall, the features indicative of murrelet nesting habitat included low elevation locations near the heads of bays, with extensive forest cover of large old-growth trees.

  1. Mapping and modelling the habitat of giant pandas in Foping Nature Reserve, China

    OpenAIRE

    Liu, X.

    2001-01-01

    The fact that only about 1000 giant pandas and 29500 km2 of panda habitat are left in the west part of China makes it an urgent issue to save this endangered animal species and protect its habitat. For effective conservation of the giant panda and its habitat, a thorough evaluation of panda habitat and panda-habitat relationship based on each individual panda nature reserve is necessary and important. Mapping has been an effective approach for wildlife habitat evaluation and monitoring. There...

  2. Análise da variação do tempo dedicado ás viagens urbanas da população de Manaus – AM, em função do modo de transporte utilizado

    Directory of Open Access Journals (Sweden)

    Aline Leite

    2012-06-01

    Full Text Available A ausência de planejamento, característica da maioria dos bairros de Manaus deixou como herança um sistema viário incompatível com o tamanho atual da cidade. Neste artigo busca-se analisar a variação do tempo dedicado às viagens urbanas em Manaus em função de três diferentes modos de transporte: ônibus, micro-ônibus e automóvel. Receptores do Sistema de Posicionamento Global (GPS e recursos de um Sistema de Informações Geográficas (SIG foram utilizados para levantar e tratar os dados das viagens urbanas realizadas. Considera-se (por tudo o que o trabalho permitiu concluir, que a metodologia adotada foi bastante consistente para o reconhecimento da variação de desempenho de modos de transporte investigados. Os percursos mais longos permitiram melhor desempenho que os mais curtos, notadamente influenciado pela área central da cidade, que registrou os trechos mais lentos para os três modos.

  3. Prioritizing tropical habitats for long-distance migratory songbirds: an assessment of habitat quality at a stopover site in Colombia

    Directory of Open Access Journals (Sweden)

    Nicholas J. Bayly

    2016-12-01

    Full Text Available Long-distance migratory birds are declining globally and migration has been identified as the primary source of mortality in this group. Despite this, our lack of knowledge of habitat use and quality at stopovers, i.e., sites where the energy for migration is accumulated, remains a barrier to designing appropriate conservation measures, especially in tropical regions. There is therefore an urgent need to assess stopover habitat quality and concurrently identify efficient and cost-effective methods for doing so. Given that fuel deposition rates directly influence stopover duration, departure fuel load, and subsequent speed of migration, they are expected to provide a direct measure of habitat quality and have the advantage of being measurable through body-mass changes. Here, we examined seven potential indicators of quality, including body-mass change, for two ecologically distinct Neotropical migratory landbirds on stopover in shade-coffee plantations and tropical humid premontane forest during spring migration in Colombia: (1 rate of body-mass change; (2 foraging rate; (3 recapture rate; (4 density; (5 flock size; (6 age and sex ratios; and (7 body-mass distribution. We found higher rates of mass change in premontane forest than in shade-coffee in Tennessee Warbler Oreothlypis peregrina, a difference that was mirrored in higher densities and body masses in forest. In Gray-cheeked Thrush Catharus minimus, a lack of recaptures in shade-coffee and higher densities in forest, also suggested that forest provided superior fueling conditions. For a reliable assessment of habitat quality, we therefore recommend using a suite of indicators, taking into account each species' ecology and methodological considerations. Our results also imply that birds stopping over in lower quality habitats may spend a longer time migrating and require more stopovers, potentially leading to important carryover effects on reproductive fitness. Evaluating habitat quality is

  4. Habitat modeling and genetic signatures of postglacial recolonization for tidal estuaries

    Science.gov (United States)

    Dolby, G. A.; Jacobs, D. K.

    2014-12-01

    Pleistocene glacial cycles are a foremost influence on the genetic diversity and species distribution patterns observed today. Though much work has centered on biotic response to such climatic forcing, little of it has regarded estuarine or other aquatic coastal taxa whose habitat formation is a function of sea level, hydrography, and coastal geomorphology. These physical parameters required for habitat formation suggest that glacial cycles impart a significant effect on such taxa through glacially driven eustatic changes. Additionally, the steepened coastline and rainfall-limited Mediterranean climate suggest limited glacial habitat for estuarine species in southern and Baja California. Here we present GIS modeled habitat for tidal estuaries for three co-distributed estuarine fishes (Gillichthys mirabilis, Quietula y-cauda, Fundulus parvipinnis) since the last glacial maximum. Parameterization of sea level and slope enables biologically relevant temporal resolution of near-millennial scale. At lowstand our approach reveals two refuges along the coast at 1000km distance from each other, with habitat rapidly increasing 15 - 12 ka during meltwater pulse 1A. Habitat area peaked in the early Holocene and began decreasing with the current stillstand roughly 7 ka, probably as a result of coastal maturation towards less tidal systems. To target the postglacial recolonization process we applied discriminant function analysis to highly polymorphic microsatellite data to partition out the alleles associated with refuges identified a priori by habitat modeling. The frequencies of these alleles were calculated for all individuals at intervening populations and regressed against geographic distance. This analysis revealed nonlinear mixing curves, suggesting uneven allelic mixing efficiency along the coastline, perhaps as a result of differential habitat origination times as indicated by the habitat models. These results highlight the dynamism of estuarine habitat in recent

  5. Revised Methods for Characterizing Stream Habitat in the National Water-Quality Assessment Program

    Science.gov (United States)

    Fitzpatrick, Faith A.; Waite, Ian R.; D'Arconte, Patricia J.; Meador, Michael R.; Maupin, Molly A.; Gurtz, Martin E.

    1998-01-01

    Stream habitat is characterized in the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program as part of an integrated physical, chemical, and biological assessment of the Nation's water quality. The goal of stream habitat characterization is to relate habitat to other physical, chemical, and biological factors that describe water-quality conditions. To accomplish this goal, environmental settings are described at sites selected for water-quality assessment. In addition, spatial and temporal patterns in habitat are examined at local, regional, and national scales. This habitat protocol contains updated methods for evaluating habitat in NAWQA Study Units. Revisions are based on lessons learned after 6 years of applying the original NAWQA habitat protocol to NAWQA Study Unit ecological surveys. Similar to the original protocol, these revised methods for evaluating stream habitat are based on a spatially hierarchical framework that incorporates habitat data at basin, segment, reach, and microhabitat scales. This framework provides a basis for national consistency in collection techniques while allowing flexibility in habitat assessment within individual Study Units. Procedures are described for collecting habitat data at basin and segment scales; these procedures include use of geographic information system data bases, topographic maps, and aerial photographs. Data collected at the reach scale include channel, bank, and riparian characteristics.

  6. Mine-associated wetlands as avian habitat

    International Nuclear Information System (INIS)

    Horstman, A.J.; Nawrot, J.R.; Woolf, A.

    1998-01-01

    Surveys for interior wetland birds at mine-associated emergent wetlands on coal surface mines in southern Illinois detected one state threatened and two state endangered species. Breeding by least bittern (Ixobrychus exilis) and common moorhen (Gallinula chloropus) was confirmed. Regional assessment of potential wetland bird habitat south of Illinois Interstate 64 identified a total of 8,109 ha of emergent stable water wetlands; 10% were associated with mining. Mine-associated wetlands with persistent hydrology and large expanses of emergent vegetation provide habitat that could potentially compensate for loss of natural wetlands in Illinois

  7. The effects of wetland habitat structure on Florida apple snail density

    Science.gov (United States)

    Karunaratne, L.B.; Darby, P.C.; Bennetts, R.E.

    2006-01-01

    Wetlands often support a variety of juxtaposed habitat patches (e.g., grass-, shrub- or tree-dominated) differentially suited to support the inhabiting fauna. The proportion of available habitat types has been affected by human activity and consequently has contributed to degrading habitat quality for some species. The Florida apple snail (Pomacea paludosa) has drawn attention as a critical prey item for wetlands wildlife and as an indicator of wetlands restoration success in peninsular Florida, USA. An apparent contradiction has evolved wherein this species appears intolerant of drying events, but these disturbances may be necessary to maintain suitable habitat structure for apple snails. We recently reported that assertions regarding intolerance to dry downs in this species were inaccurate. Here, we compared snail density in habitats with (wet prairie) and without (slough) emergent macrophytes, as well as evaluating the effects of structural attributes within the broad wet prairie habitat type. Snail densities were greater in prairies relative to sloughs (??2= 12.90, df=1, P=0.0003), often by a factor of two to three. Within wet prairie habitats, we found greater snail densities in Panicum hemitomon as compared to Eleocharis cellulosa (??2=31.45, df=1, P=0.0001). Significantly fewer snails were found in dense E. cellulosa as compared to habitats with lower stem density (??2= 10.73, df=1, P=0.011). Our results indicate that wet prairie habitat supports greater snail densities than nymphaea-dominatd slough. Our results have implications for wetlands water management in that continuous inundation has been shown to convert wet prairie to slough habitat, and we suggest this should be avoided in support of apple snails and their predators. ?? 2006, The Society of Wetland Scientists.

  8. Predicting freshwater habitat integrity using land-use surrogates

    African Journals Online (AJOL)

    2007-04-02

    Apr 2, 2007 ... Quantification of potential surrogates of freshwater habitat integrity. We chose a series of land-use variables that might be suitable predictors for assessing freshwater habitat integrity from the land cover map (CSIR 2005) and added separate GIS surfaces for human population density and the distribution of ...

  9. Habitat-specific effects of climate change on a low-mobility Arctic spider species

    DEFF Research Database (Denmark)

    Bowden, Joseph James; Hansen, Rikke Reisner; Olsen, Kent

    2015-01-01

    Abstract Terrestrial ecosystems are heterogeneous habitat mosaics of varying vegetation types that are differentially affected by climate change. Arctic plant communities, for example, are changing faster in moist habitats than in dry habitats and abiotic changes like snowmelt vary locally among...... was significantly related to the timing of snowmelt and differed significantly between the sexes and habitats with the spiders in the mesic habitat showing a stronger temporal response to later snowmelt. Juvenile/ female ratios also differed significantly between habitats; as did the overall abundance...

  10. GIS-based approach for quantifying landscape connectivity of Javan Hawk-Eagle habitat

    Science.gov (United States)

    Nurfatimah, C.; Syartinilia; Mulyani, Y. A.

    2018-05-01

    Javan Hawk-Eagle (Nisaetus bartelsi; JHE) is a law-protected endemic raptor which currently faced the decreased in number and size of habitat patches that will lead to patch isolation and species extinction. This study assessed the degree of connectivity between remnant habitat patches in central part of Java by utilizing Conefor Sensinode software as an additional tool for ArcGIS. The connectivity index was determined by three fractions which are infra, flux and connector. Using connectivity indices successfully identified 4 patches as core habitat, 9 patches as stepping-stone habitat and 6 patches as isolated habitat were derived from those connectivity indices. Those patches then being validated with land cover map derived from Landsat 8 of August 2014. 36% of core habitat covered by natural forest, meanwhile stepping stone habitat has 55% natural forest and isolated habitat covered by 59% natural forest. Isolated patches were caused by zero connectivity (PCcon = 0) and the patch size which too small to support viable JHE population. Yet, the condition of natural forest and the surrounding matrix landscape in isolated patches actually support the habitat need. Thus, it is very important to conduct the right conservation management system based on the condition of each patches.

  11. Southern Monterey Bay Littoral Cell CRSMP Sensitive Habitat 2008

    Data.gov (United States)

    California Natural Resource Agency — One of the most important functions of the southern Monterey Bay coastal system is its role as a habitat for a unique flora and fauna. The beaches are habitat for...

  12. Southern Monterey Bay Littoral Cell CRSMP Sensitive Habitat 2008

    Data.gov (United States)

    California Department of Resources — One of the most important functions of the southern Monterey Bay coastal system is its role as a habitat for a unique flora and fauna. The beaches are habitat for...

  13. Fish thermal habitat current use and simulation of thermal habitat availability in lakes of the Argentine Patagonian Andes under climate change scenarios RCP 4.5 and RCP 8.5.

    Science.gov (United States)

    Vigliano, Pablo H; Rechencq, Magalí M; Fernández, María V; Lippolt, Gustavo E; Macchi, Patricio J

    2018-09-15

    Habitat use in relation to the thermal habitat availability and food source as a forcing factor on habitat selection and use of Percichthys trucha (Creole perch), Oncorhynchus mykiss (rainbow trout), Salmo trutta (brown trout) and Salvelinus fontinalis (brook trout) were determined as well as future potential thermal habitat availability for these species under climate change scenarios Representative Concentration Pathways 4.5 and 8.5. This study was conducted in three interconnected lakes of Northern Patagonia (Moreno Lake system). Data on fish abundance was obtained through gill netting and hydroacoustics, and thermal profiles and fish thermal habitat suitability index curves were used to identify current species-specific thermal habitat use. Surface air temperatures from the (NEX GDDP) database for RCP scenarios 4.5 and 8.5 were used to model monthly average temperatures of the water column up to the year 2099 for all three lakes, and to determine potential future habitat availability. In addition, data on fish diet were used to determine whether food could act as a forcing factor in current habitat selection. The four species examined do not use all the thermally suitable habitats currently available to them in the three lakes, and higher fish densities are not necessarily constrained to their "fundamental thermal niches" sensu Magnuson et al. (1979), as extensive use is made of less suitable habitats. This is apparently brought about by food availability acting as a major forcing factor in habitat selection and use. Uncertainties related to the multidimensionality inherent to habitat selection and climate change imply that fish resource management in Patagonia will not be feasible through traditional incremental policies and strategic adjustments based on short-term predictions, but will have to become highly opportunistic and adaptive. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Learning the Hard Way: Imprinting Can Enhance Enforced Shifts in Habitat Choice

    Directory of Open Access Journals (Sweden)

    Niclas Vallin

    2011-01-01

    Full Text Available We investigated the potential importance of learning in habitat choice within a young hybrid zone of two closely related species of birds. Pied flycatchers (Ficedula hypoleuca are being excluded from deciduous habitats into a mixed forest type by collared flycatchers (F. albicollis. We investigated whether this enforced habitat shift influenced reproductive isolation between the two species, and, by cross-fostering nestlings, we tested whether learning may lead to a corresponding shift in habitat choice in consecutive generations. Our results show that the majority of the recruits, even if translocated across different habitat types, return to breed in the area where they were fostered. As male pied flycatchers were more likely to hybridize in the originally preferred habitat, we argue that early imprinting on an alternate habitat can play an important role in increasing reproductive isolation and facilitate regional coexistence between species experiencing secondary contact.

  15. Quantification of habitat fragmentation reveals extinction risk in terrestrial mammals

    Science.gov (United States)

    Crooks, Kevin R.; Burdett, Christopher L.; Theobald, David M.; King, Sarah R. B.; Rondinini, Carlo; Boitani, Luigi

    2017-01-01

    Although habitat fragmentation is often assumed to be a primary driver of extinction, global patterns of fragmentation and its relationship to extinction risk have not been consistently quantified for any major animal taxon. We developed high-resolution habitat fragmentation models and used phylogenetic comparative methods to quantify the effects of habitat fragmentation on the world’s terrestrial mammals, including 4,018 species across 26 taxonomic Orders. Results demonstrate that species with more fragmentation are at greater risk of extinction, even after accounting for the effects of key macroecological predictors, such as body size and geographic range size. Species with higher fragmentation had smaller ranges and a lower proportion of high-suitability habitat within their range, and most high-suitability habitat occurred outside of protected areas, further elevating extinction risk. Our models provide a quantitative evaluation of extinction risk assessments for species, allow for identification of emerging threats in species not classified as threatened, and provide maps of global hotspots of fragmentation for the world’s terrestrial mammals. Quantification of habitat fragmentation will help guide threat assessment and strategic priorities for global mammal conservation. PMID:28673992

  16. Libby/Hungry Horse Dams Wildlife Mitigation Habitat Protection : Interim Report.

    Energy Technology Data Exchange (ETDEWEB)

    Wood, Marilyn

    1991-04-01

    The Columbia River Basin Fish and Wildlife Program identified mitigation goals for Hungry Horse and Libby dams (1987). Specific programs goals included: (1) protect and/or enhance 4565 acres of wetland habitat in the Flathead Valley; (2) protect 2462 acres of prairie habitat within the vicinity of the Tobacco Plains Columbian sharp-tailed grouse; (3) protect 8590 acres riparian habitat in northwest Montana for grizzly and black bears; and (4) protect 11,500 acres of terrestrial furbearer habitat through cooperative agreements with state and federal agencies and private landowners. The purpose of this project is to continue to develop and obtain information necessary to evaluate and implement specific wildlife habitat protection actions in northwestern Montana. This report summarizes project work completed between May 1, 1990, and December 31, 1990. There were three primary project objectives during this time: obtain specific information necessary to develop the mitigation program for Columbian sharp-tailed grouse; continue efforts necessary to develop, refine, and coordinate the mitigation programs for waterfowl/wetlands and grizzly/black bears; determine the opportunity and appropriate strategies for protecting terrestrial furbearer habitat by lease or management agreements on state, federal and private lands. 19 refs., 1 tab.

  17. As variações da forma do sifão carotídeo na arteriografia cerebral: estudo sobre 120 casos não tumorais

    Directory of Open Access Journals (Sweden)

    A. Mattos Pimenta

    1954-06-01

    Full Text Available O estudo de 120 arteriogramas de pacientes em que foi comprovada a inexistência de lesão que ocupa espaço intracraniano, permitiu o reconhecimento de várias formas de sifão carotídeo normal. Foi assim possível fazer uma classificação anatômica dos vários tipos e concluir que a forma do sifão não permite, sozinha, fazer o diagnóstico topográfico de tumores intracranianos. É importante reconhecer exatamente os limites do sifão, a fim de localizar, precisamente, os aneurismas da carótida interna. Do exposto podemos tirar duas ordens de conclusões: 1 Conclusões anatômicas - O sifão carotídeo normal não apresenta grande número de variações de forma, podendo ser reconhecidos dois tipos básicos: angulados e arredondados. Os primeiros subdividem-se em angulados com ramos oblíquos (ângulo agudo ou ângulo obtuso e angulados com um ramo horizontal (superior ou inferior. Os segundos (arredondados dividem-se em três subtipos: semi-elíptico, em alça (horizontal ou oblíquo e em S (superior, inferior ou duplo. Nos grupos e subgrupos cada segmento do sifão pode apresentar variação no comprimento e espessura, como é evidente à observação dos esquemas. 2 Conclusões neurocirúrgicas - A existência de grande número de formas consideradas como normais de sifão carotídeo leva à conclusão de que não é possível basear o diagnóstico de tumor, ou melhor, de lesão que ocupa espaço intracraniano, exclusivamente pela imagem arteriográfica do sifão. As variações fisiológicas do sifão, somadas às das artérias do grupo silviano e da cerebral anterior, trazem dificuldades diagnosticas que obrigam o neurocirurgião a procurar o maior número de indícios para fazer a interpretação correta do exame. Assim sendo, na rotina neurocirúrgica é aconselhável que os arteriogramas sejam feitos pelo menos em duas posições: perfil e ântero-posterior. E' importante reconhecer bem os limites do sifão para se estabelecer

  18. Using multiscale spatial models to assess potential surrogate habitat for an imperiled reptile.

    Directory of Open Access Journals (Sweden)

    Jennifer M Fill

    Full Text Available In evaluating conservation and management options for species, practitioners might consider surrogate habitats at multiple scales when estimating available habitat or modeling species' potential distributions based on suitable habitats, especially when native environments are rare. Species' dependence on surrogates likely increases as optimal habitat is degraded and lost due to anthropogenic landscape change, and thus surrogate habitats may be vital for an imperiled species' survival in highly modified landscapes. We used spatial habitat models to examine a potential surrogate habitat for an imperiled ambush predator (eastern diamondback rattlesnake, Crotalus adamanteus; EDB at two scales. The EDB is an apex predator indigenous to imperiled longleaf pine ecosystems (Pinus palustris of the southeastern United States. Loss of native open-canopy pine savannas and woodlands has been suggested as the principal cause of the species' extensive decline. We examined EDB habitat selection in the Coastal Plain tidewater region to evaluate the role of marsh as a potential surrogate habitat and to further quantify the species' habitat requirements at two scales: home range (HR and within the home range (WHR. We studied EDBs using radiotelemetry and employed an information-theoretic approach and logistic regression to model habitat selection as use vs.We failed to detect a positive association with marsh as a surrogate habitat at the HR scale; rather, EDBs exhibited significantly negative associations with all landscape patches except pine savanna. Within home range selection was characterized by a negative association with forest and a positive association with ground cover, which suggests that EDBs may use surrogate habitats of similar structure, including marsh, within their home ranges. While our HR analysis did not support tidal marsh as a surrogate habitat, marsh may still provide resources for EDBs at smaller scales.

  19. Habitat Evaluation Procedures (HEP) Report; Calispell Creek Project, Technical Report 2004-2005.

    Energy Technology Data Exchange (ETDEWEB)

    Entz, Ray

    2005-02-01

    On July 13, 2004, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the Calispell Creek property, an acquisition completed by the Kalispel Tribe of Indians in February 2004. Evaluation species and appropriate models include Canada goose, mallard, muskrat, yellow warbler, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The Calispell Creek Project provides a total of 138.17 Habitat Units (HUs) for the species evaluated. Emergent wetland habitat provides 5.16 HUs for mallard and muskrat. Grassland provides 132.02 HUs for mallard and Canada goose. Scrub-shrub vegetation provides 0.99 HUs for yellow warbler and white-tailed deer. The objective of using HEP at the Calispell Creek Project and other protected properties is to document the quality and quantity of available habitat for selected wildlife species. In this way, HEP provides information on the relative value of the same area at future points in time so that the effect of management activities on wildlife habitat can be quantified. When combined with other tools, the baseline HEP will be used to determine the most effective on-site management, restoration, and enhancement actions to increase habitat suitability for targeted species. The same process will be replicated every five years to quantitatively evaluate the effectiveness of management strategies in improving and maintaining habitat conditions while providing additional crediting to BPA for enhanced habitat values.

  20. Movements and habitat use of mallard broods in northeastern California

    Science.gov (United States)

    Mauser, D.M.; Jarvis, R.L.; Gilmer, D.S.

    1994-01-01

    To increase recruitment of mallards (Anas platyrhynchos), wildlife managers must understand the habitat and space needs of mallard broods. During 1989-90, we examined the movements, home range, and habitat use of 27 radio-marked mallard broods on Lower Klamath National Wildlife Refuge, California. Twelve of the 27 broods made 22 relocation movements (>1,000 m in 24 hr) in the first week (n = 6) and after the fourth (n = 16) week of life. Mean home range size was 0.93 km2 (SE = 0.25) and did not differ between years (P = 0.26). Brood-rearing females selected seasonally flooded wetlands with a cover component and avoided open or permanently flooded habitats. In 1989, broods hatched in permanent wetlands were less successful in fledging (P = 0.006) radio-marked ducklings than broods from seasonal wetlands, suggesting habitat availability or movement to preferred habitats may affect duckling survival.

  1. River habitat assessment for ecological restoration of Wei River Basin, China.

    Science.gov (United States)

    Yang, Tao; Wang, Shuo; Li, Xiaoping; Wu, Ting; Li, Li; Chen, Jia

    2018-04-11

    As an important composition component of river ecosystems, river habitats must undergo quality assessment to potentially provide scientific basis for river ecological restoration. Substrate composition, habitat complexity, bank erosion degree, river meandering degree, human activity intensity, vegetation buffer width, water quality, and water condition were determined as indicators for river habitat assessment. The comprehensive habitat quality index (CHQI) was established for the Wei River Basin. In addition, the indicator values were determined on the basis of a field investigation at 12 national hydrological stations distributed across the Wei, Jing, and Beiluo Rivers. The analytic hierarchy process was used to determine the indicator weights and thus distinguish the relative importance of the assessment indicator system. Results indicated that the average CHQIs for the Wei, Jing, and Beiluo Rivers were 0.417, 0.508, and 0.304, respectively. The river habitat quality for the three rivers was well. As for the whole river basin, the river habitat quality for 25% of the cross section was very well, the other 25% was well, and the 50% remaining was in critical state. The river habitat quality of the Jing River was better than that of the Wei and Beiluo Rivers.

  2. Monitoring and mapping selected riparian habitat along the lower Snake River

    Energy Technology Data Exchange (ETDEWEB)

    Downs, J. L; Tiller, B. L [Pacific Northwest Lab., Richland, WA (United States); Witter, M. [Shannon and Wilson, Inc., Seattle, WA (United States). Geotechnical and Environmental Consultants, Seattle, Washington (United States); Mazaika, R. [Corps of Engineers, Portland, OR (United States)

    1996-01-01

    Studies in this document were initiated to establish baseline information on riparian and wetland habitat conditions at the areas studied under the current reservoir operations on the lower Snake River. Two approaches were used to assess habitat at 28 study sites selected on the four pools on the lower Snake River. These areas all contribute significant riparian habitat along the river, and several of these areas are designated habitat management units. At 14 of the 28 sites, we monitored riparian habitat on three dates during the growing season to quantify vegetation abundance and composition along three transects: soil nutrients, moisture, and pH and water level and pH. A second approach involved identifying any differences in the extent and amount of riparian/wetland habitat currently found at the study areas from that previously documented. We used both ground and boat surveys to map and classify the changes in vegetative cover along the shoreline at the 14 monitoring sites and at 14 additional sites along the lower Snake selected to represent various riparian/wetland habitat conditions. Results of these mapping efforts are compared with maps of cover types previously generated using aerial photography taken in 1987.

  3. Physical stream habitat dynamics in Lower Bear Creek, northern Arkansas

    Science.gov (United States)

    Reuter, Joanna M.; Jacobson, Robert B.; Elliott, Caroline M.

    2003-01-01

    We evaluated the roles of geomorphic and hydrologic dynamics in determining physical stream habitat in Bear Creek, a stream with a 239 km2 drainage basin in the Ozark Plateaus (Ozarks) in northern Arkansas. During a relatively wet 12-month monitoring period, the geomorphology of Bear Creek was altered by a series of floods, including at least four floods with peak discharges exceeding a 1-year recurrence interval and another flood with an estimated 2- to 4-year recurrence interval. These floods resulted in a net erosion of sediment from the study reach at Crane Bottom at rates far in excess of other sites previously studied in the Ozarks. The riffle-pool framework of the study reach at Crane Bottom was not substantially altered by these floods, but volumes of habitat in riffles and pools changed. The 2- to 4-year flood scoured gravel from pools and deposited it in riffles, increasing the diversity of available stream habitat. In contract, the smaller floods eroded gravel from the riffles and deposited it in pools, possibly flushing fine sediment from the substrate but also decreasing habitat diversity. Channel geometry measured at the beginning of the study was use to develop a two-dimensional, finite-element hydraulic model at assess how habitat varies with hydrologic dynamics. Distributions of depth and velocity simulated over the range of discharges observed during the study (0.1 to 556 cubic meters per second, cms) were classified into habitat units based on limiting depths and Froude number criteria. The results indicate that the areas of habitats are especially sensitive to change to low to medium flows. Races (areas of swift, relatively deep water downstream from riffles) disappear completely at the lowest flows, and riffles (areas of swift, relatively shallow water) contract substantially in area. Pools also contract in area during low flow, but deep scours associated with bedrock outcrops sustain some pool area even at the lowest modeled flows. Modeled

  4. Connecting the fragmented habitat of endangered mammals in the landscape of Riau–Jambi–Sumatera Barat (RIMBA, central Sumatra, Indonesia (connecting the fragmented habitat due to road development

    Directory of Open Access Journals (Sweden)

    Barano Siswa Sulistyawan

    2017-01-01

    Full Text Available The trend of wildlife habitat fragmentation worldwide continues as a result of anthropogenic activities on development of a linear infrastructure and land use changes, which is often implemented as part of spatial planning policies. In this paper we expand upon an existing approach to design wildlife corridors through habitat quality assessment. We used models of Habitat Quality of Integrated Valuation of Ecosystem Services and Trade-offs (InVEST and Corridor Design tools. The habitat quality model of InVEST provides a rapid approach to assess status and change of biodiversity, and can contribute to enhanced corridor design of fragmented wildlife habitat. We conducted an assessment of habitat quality of the RIMBA corridor landscape, which is part of Riau, Jambi and West Sumatra provinces of central Sumatra Island. The result of the habitat quality model was used as the main input to evaluate habitat connectivity and assess the target segment of roads that cross the modelled corridor. We found 20 wildland blocks, the total area of the corridor modelled including wildland blocks was calculated as about 0.77 million hectares. We have obtained accurate quantitative measurement of the length of roads crossing the corridor, with a total of 417.78 km (artery 10.31 km; collector 19.52 km; and local 1987.9 km roads. This method can be replicated as an approach in valuing the quality of habitat as part of the implementation of the presidential decree of Sumatra Island Spatial Planning. This may also be applied to the spatial planning of other major islands in Indonesia and elsewhere.

  5. Global patterns of fragmentation and connectivity of mammalian carnivore habitat

    OpenAIRE

    Crooks, Kevin R.; Burdett, Christopher L.; Theobald, David M.; Rondinini, Carlo; Boitani, Luigi

    2011-01-01

    Although mammalian carnivores are vulnerable to habitat fragmentation and require landscape connectivity, their global patterns of fragmentation and connectivity have not been examined. We use recently developed high-resolution habitat suitability models to conduct comparative analyses and to identify global hotspots of fragmentation and connectivity for the world's terrestrial carnivores. Species with less fragmentation (i.e. more interior high-quality habitat) had larger geographical ranges...

  6. Competition and habitat selection in a forest-floor small mammal fauna

    Energy Technology Data Exchange (ETDEWEB)

    Dueser, R D [Univ. of Virginia, Charlottesville; Hallett, J G

    1980-01-01

    In a study of habitat exploitation in a forest-floor small mammal community, we have collected habitat and population data for Peromyscus leucopus, Ochrotomys nuttalli, and Tamias striatus. Using multiple regression analysis, researchers estimate the effects of habitat selection and competition on the local distributions of these species during three seasons. Each of the partial regression coefficients relating the density of an independent species to the density of the dependent species is negative. This result indicates that competition is pervasive among these species. Competitive ability and habitat selectivity both increase in the order Peromyscus-Tamias-Ochrotomys. Peromyscus is a poorly competitive habitat generalist, Ochrotomys is a strongly competitive habitat specialist, and Tamias is intermediate in both respects. The competitive hierarchy is stable between seasons. These results both confirm the conclusions reached in previous studies of this small mammal community and suggest the design of experiments to further clarify the mode and consequences of interaction between these species.

  7. Urban habitat complexity affects species richness but not environmental filtering of morphologically-diverse ants

    Directory of Open Access Journals (Sweden)

    Alessandro Ossola

    2015-10-01

    Full Text Available Habitat complexity is a major determinant of structure and diversity of ant assemblages. Following the size-grain hypothesis, smaller ant species are likely to be advantaged in more complex habitats compared to larger species. Habitat complexity can act as an environmental filter based on species size and morphological traits, therefore affecting the overall structure and diversity of ant assemblages. In natural and semi-natural ecosystems, habitat complexity is principally regulated by ecological successions or disturbance such as fire and grazing. Urban ecosystems provide an opportunity to test relationships between habitat, ant assemblage structure and ant traits using novel combinations of habitat complexity generated and sustained by human management. We sampled ant assemblages in low-complexity and high-complexity parks, and high-complexity woodland remnants, hypothesizing that (i ant abundance and species richness would be higher in high-complexity urban habitats, (ii ant assemblages would differ between low- and high-complexity habitats and (iii ants living in high-complexity habitats would be smaller than those living in low-complexity habitats. Contrary to our hypothesis, ant species richness was higher in low-complexity habitats compared to high-complexity habitats. Overall, ant assemblages were significantly different among the habitat complexity types investigated, although ant size and morphology remained the same. Habitat complexity appears to affect the structure of ant assemblages in urban ecosystems as previously observed in natural and semi-natural ecosystems. However, the habitat complexity filter does not seem to be linked to ant morphological traits related to body size.

  8. Urban habitat complexity affects species richness but not environmental filtering of morphologically-diverse ants

    Science.gov (United States)

    Nash, Michael A.; Christie, Fiona J.; Hahs, Amy K.; Livesley, Stephen J.

    2015-01-01

    Habitat complexity is a major determinant of structure and diversity of ant assemblages. Following the size-grain hypothesis, smaller ant species are likely to be advantaged in more complex habitats compared to larger species. Habitat complexity can act as an environmental filter based on species size and morphological traits, therefore affecting the overall structure and diversity of ant assemblages. In natural and semi-natural ecosystems, habitat complexity is principally regulated by ecological successions or disturbance such as fire and grazing. Urban ecosystems provide an opportunity to test relationships between habitat, ant assemblage structure and ant traits using novel combinations of habitat complexity generated and sustained by human management. We sampled ant assemblages in low-complexity and high-complexity parks, and high-complexity woodland remnants, hypothesizing that (i) ant abundance and species richness would be higher in high-complexity urban habitats, (ii) ant assemblages would differ between low- and high-complexity habitats and (iii) ants living in high-complexity habitats would be smaller than those living in low-complexity habitats. Contrary to our hypothesis, ant species richness was higher in low-complexity habitats compared to high-complexity habitats. Overall, ant assemblages were significantly different among the habitat complexity types investigated, although ant size and morphology remained the same. Habitat complexity appears to affect the structure of ant assemblages in urban ecosystems as previously observed in natural and semi-natural ecosystems. However, the habitat complexity filter does not seem to be linked to ant morphological traits related to body size. PMID:26528416

  9. Global habitat suitability for framework-forming cold-water corals.

    Directory of Open Access Journals (Sweden)

    Andrew J Davies

    Full Text Available Predictive habitat models are increasingly being used by conservationists, researchers and governmental bodies to identify vulnerable ecosystems and species' distributions in areas that have not been sampled. However, in the deep sea, several limitations have restricted the widespread utilisation of this approach. These range from issues with the accuracy of species presences, the lack of reliable absence data and the limited spatial resolution of environmental factors known or thought to control deep-sea species' distributions. To address these problems, global habitat suitability models have been generated for five species of framework-forming scleractinian corals by taking the best available data and using a novel approach to generate high resolution maps of seafloor conditions. High-resolution global bathymetry was used to resample gridded data from sources such as World Ocean Atlas to produce continuous 30-arc second (∼1 km(2 global grids for environmental, chemical and physical data of the world's oceans. The increased area and resolution of the environmental variables resulted in a greater number of coral presence records being incorporated into habitat models and higher accuracy of model predictions. The most important factors in determining cold-water coral habitat suitability were depth, temperature, aragonite saturation state and salinity. Model outputs indicated the majority of suitable coral habitat is likely to occur on the continental shelves and slopes of the Atlantic, South Pacific and Indian Oceans. The North Pacific has very little suitable scleractinian coral habitat. Numerous small scale features (i.e., seamounts, which have not been sampled or identified as having a high probability of supporting cold-water coral habitat were identified in all ocean basins. Field validation of newly identified areas is needed to determine the accuracy of model results, assess the utility of modelling efforts to identify vulnerable marine

  10. Variações na composição e estrutura da vegetação permitem detectar agrupamentos florísticos em uma Floresta Subtropical Atlântica no Sul do Brasil?

    Directory of Open Access Journals (Sweden)

    João Paulo de Maçaneiro

    2016-12-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2016v29n4p43 As variações da vegetação em função da posição topográfica têm despertado o interesse dos pesquisadores. Entretanto, poucos estudos verificaram as associações florísticas formadas pela posição topográfica de uma encosta. Neste trabalho, analisamos se as variações na vegetação permitem detectar agrupamentos florísticos em uma Floresta Pluvial Subtropical. A vegetação foi amostrada em 25 parcelas de 400 m² distribuídas sistematicamente, onde foram medidos os indivíduos com DAP ≥ 5,0 cm. Amostramos 1.727 indivíduos e 144 espécies. A ordenação NMDS segregou três grupos em função da posição topográfica da encosta (Monte Carlo, P ≥ 0,05; ANOSIM, P < 0,001. Euterpe edulis e Sloanea guianensis se destacaram nos terços inferior e médio da encosta, enquanto Ocotea aciphylla e Alchornea triplinervia se destacaram no terço superior. Algumas espécies se mostraram indicadoras dos setores analisados, como é o caso de Actinostemon concolor e Alsophila setosa no terço inferior, Cyathea corcovadensis e Rudgea recurva no terço médio e Myrcia pulchra e Podocarpus sellowii no terço superior. Nossos resultados indicaram que as variações florísticas e estruturais observadas por Veloso e Klein (1959 e Klein (1980; 1984 para o Vale do Itajaí em Santa Catarina apresentam validade estatística nos dias atuais, pois verificamos a formação de diferentes grupos de acordo com a posição topográfica da encosta.

  11. Assessing range-wide habitat suitability for the Lesser Prairie-Chicken

    Science.gov (United States)

    Jarnevich, Catherine S.; Holcombe, Tracy R.; Grisham, Blake A.; Timmer, Jennifer M.; Boal, Clint W.; Butler, Matthew; Pitman, James C.; Kyle, Sean; Klute, David; Beauprez, Grant M.; Janus, Allan; Van Pelt, William E.

    2016-01-01

    Population declines of many wildlife species have been linked to habitat loss incurred through land-use change. Incorporation of conservation planning into development planning may mitigate these impacts. The threatened Lesser Prairie-Chicken (Tympanuchus pallidicinctus) is experiencing loss of native habitat and high levels of energy development across its multijurisdictional range. Our goal was to explore relationships of the species occurrence with landscape characteristics and anthropogenic effects influencing its distribution through evaluation of habitat suitability associated with one particular habitat usage, lekking. Lekking has been relatively well-surveyed, though not consistently, in all jurisdictions. All five states in which Lesser Prairie-Chickens occur cooperated in development of a Maxent habitat suitability model. We created two models, one with state as a factor and one without state. When state was included it was the most important predictor, followed by percent of land cover consisting of known or suspected used vegetation classes within a 5000 m area around a lek. Without state, land cover was the most important predictor of relative habitat suitability for leks. Among the anthropogenic predictors, landscape condition, a measure of human impact integrated across several factors, was most important, ranking third in importance without state. These results quantify the relative suitability of the landscape within the current occupied range of Lesser Prairie-Chickens. These models, combined with other landscape information, form the basis of a habitat assessment tool that can be used to guide siting of development projects and targeting of areas for conservation.

  12. Stopover habitats of spring migrating surf scoters in southeast Alaska

    Science.gov (United States)

    Lok, E.K.; Esler, Daniel; Takekawa, John Y.; De La Cruz, S.W.; Sean, Boyd W.; Nysewander, D.R.; Evenson, J.R.; Ward, D.H.

    2011-01-01

    Habitat conditions and nutrient reserve levels during spring migration have been suggested as important factors affecting population declines in waterfowl, emphasizing the need to identify key sites used during spring and understand habitat features and resource availability at stopover sites. We used satellite telemetry to identify stopover sites used by surf scoters migrating through southeast Alaska during spring. We then contrasted habitat features of these sites to those of random sites to determine habitat attributes corresponding to use by migrating scoters. We identified 14 stopover sites based on use by satellite tagged surf scoters from several wintering sites. We identified Lynn Canal as a particularly important stopover site for surf scoters originating throughout the Pacific winter range; approximately half of tagged coastally migrating surf scoters used this site, many for extended periods. Stopover sites were farther from the mainland coast and closer to herring spawn sites than random sites, whereas physical shoreline habitat attributes were generally poor predictors of site use. The geography and resource availability within southeast Alaska provides unique and potentially critical stopover habitat for spring migrating surf scoters. Our work identifies specific sites and habitat resources that deserve conservation and management consideration. Aggregations of birds are vulnerable to human activity impacts such as contaminant spills and resource management decisions. This information is of value to agencies and organizations responsible for emergency response planning, herring fisheries management, and bird and ecosystem conservation. Copyright ?? 2011 The Wildlife Society.

  13. Habitat degradation may affect niche segregation patterns in lizards

    Science.gov (United States)

    Pelegrin, N.; Chani, J. M.; Echevarria, A. L.; Bucher, E. H.

    2013-08-01

    Lizards partition resources in three main niche dimensions: time, space and food. Activity time and microhabitat use are strongly influenced by thermal environment, and may differ between species according to thermal requirements and tolerance. As thermal characteristics are influenced by habitat structure, microhabitat use and activity of lizards can change in disturbed habitats. We compared activity and microhabitat use of two abundant lizard species of the Semi-arid Chaco of Argentina between a restored and a highly degraded Chaco forest, to determine how habitat degradation affects lizard segregation in time and space, hypothesizing that as activity and microhabitat use of lizards are related to habitat structure, activity and microhabitat use of individual species can be altered in degraded habitats, thus changing segregation patterns between them. Activity changed from an overlapped pattern in a restored forest to a segregated pattern in a degraded forest. A similar trend was observed for microhabitat use, although to a less extent. No correlation was found between air temperature and lizard activity, but lizard activity varied along the day and among sites. Contrary to what was believed, activity patterns of neotropical diurnal lizards are not fixed, but affected by multiple factors related to habitat structure and possibly to interspecific interactions. Changes in activity patterns and microhabitat use in degraded forests may have important implications when analyzing the effects of climate change on lizard species, due to synergistic effects.

  14. Bee assemblage in habitats associated with Brassica napus L.

    Directory of Open Access Journals (Sweden)

    Rosana Halinski

    2015-09-01

    Full Text Available ABSTRACTAssessments in agricultural crops indicate that alterations in the landscape adjacent to the crops can result in reduced productivity due to loss or low abundance of pollinating agents. In the canola crop, production is partially dependent on insect pollination. Therefore, knowledge of the faunal diversity within and near crop fields is key for the management of these insects and consequently for the increase in productivity. This study aimed to determine and compare the diversity of bees in habitats associated with canola fields in southern Brazil. Bees were captured in four agricultural areas using pan traps in three habitat classes: (1 flowering canola crop, (2 forest remnant, and (3 grassland vegetation. The highest abundance of bees was observed in the grassland vegetation (50% and in the flowering canola field (47%. Eight species common to the three habitat classes were recorded, four of which are represented by native social bees. In addition, a single or a few individuals represented species that were exclusive to a specific habitat class; eight species were collected exclusively in the interior of the canola field, 51 in the grassland vegetation, and six in the forest remnant. The majority of the rare species recorded exhibits subsocial or solitary behaviour and inhabit open places. The composition of bee groups differed between the habitats showing the importance of maintaining habitat mosaics with friendly areas for pollinators, which promote the pollination service for canola flowers.

  15. Resource distributions among habitats determine solitary bee offspring production in a mosaic landscape.

    Science.gov (United States)

    Williams, Neal M; Kremen, Claire

    2007-04-01

    Within mosaic landscapes, many organisms depend on attributes of the environment that operate over scales ranging from a single habitat patch to the entire landscape. One such attribute is resource distribution. Organisms' reliance on resources from within a local patch vs. those found among habitats throughout the landscape will depend on local habitat quality, patch quality, and landscape composition. The ability of individuals to move among complementary habitat types to obtain various resources may be a critical mechanism underlying the dynamics of animal populations and ultimately the level of biodiversity at different spatial scales. We examined the effects that local habitat type and landscape composition had on offspring production and survival of the solitary bee Osmia lignaria in an agri-natural landscape in California (U.S.A.). Female bees were placed on farms that did not use pesticides (organic farms), on farms that did use pesticides (conventional farms), or in seminatural riparian habitats. We identified pollens collected by bees nesting in different habitat types and matched these to pollens of flowering plants from throughout the landscape. These data enabled us to determine the importance of different plant species and habitat types in providing food for offspring, and how this importance changed with landscape and local nesting-site characteristics. We found that increasing isolation from natural habitat significantly decreased offspring production and survival for bees nesting at conventional farms, had weaker effects on bees in patches of seminatural habitat, and had little impact on those at organic farm sites. Pollen sampled from nests showed that females nesting in both farm and seminatural habitats relied on pollen from principally native plant species growing in seminatural habitat. Thus connectivity among habitats was critical for offspring production. Females nesting on organic farms were buffered to isolation effects by switching to

  16. Satellite-based remote sensing of running water habitats at large riverscape scales: Tools to analyze habitat heterogeneity for river ecosystem management

    Science.gov (United States)

    Hugue, F.; Lapointe, M.; Eaton, B. C.; Lepoutre, A.

    2016-01-01

    We illustrate an approach to quantify patterns in hydraulic habitat composition and local heterogeneity applicable at low cost over very large river extents, with selectable reach window scales. Ongoing developments in remote sensing and geographical information science massively improve efficiencies in analyzing earth surface features. With the development of new satellite sensors and drone platforms and with the lowered cost of high resolution multispectral imagery, fluvial geomorphology is experiencing a revolution in mapping streams at high resolution. Exploiting the power of aerial or satellite imagery is particularly useful in a riverscape research framework (Fausch et al., 2002), where high resolution sampling of fluvial features and very large coverage extents are needed. This study presents a satellite remote sensing method that requires very limited field calibration data to estimate over various scales ranging from 1 m to many tens or river kilometers (i) spatial composition metrics for key hydraulic mesohabitat types and (ii) reach-scale wetted habitat heterogeneity indices such as the hydromorphological index of diversity (HMID). When the purpose is hydraulic habitat characterization applied over long river networks, the proposed method (although less accurate) is much less computationally expensive and less data demanding than two dimensional computational fluid dynamics (CFD). Here, we illustrate the tools based on a Worldview 2 satellite image of the Kiamika River, near Mont Laurier, Quebec, Canada, specifically over a 17-km river reach below the Kiamika dam. In the first step, a high resolution water depth (D) map is produced from a spectral band ratio (calculated from the multispectral image), calibrated with limited field measurements. Next, based only on known river discharge and estimated cross section depths at time of image capture, empirical-based pseudo-2D hydraulic rules are used to rapidly generate a two-dimensional map of flow velocity

  17. Tidal Creek Sentinel Habitat Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Ecological Research, Assessment and Prediction's Tidal Creeks: Sentinel Habitat Database was developed to support the National Oceanic and Atmospheric...

  18. An artificial water body provides habitat for an endangered estuarine seahorse species

    Science.gov (United States)

    Claassens, Louw

    2016-10-01

    Anthropogenic development, especially the transformation of natural habitats to artificial, is a growing concern within estuaries and coastal areas worldwide. Thesen Islands marina, an artificial water body, added 25 ha of new estuarine habitat to the Knysna Estuary in South Africa, home to the Knysna seahorse. This study aimed to answer: (I) Can an artificial water body provide suitable habitat for an endangered seahorse species? And if so (II) what characteristics of this new habitat are important in terms of seahorse utilization? Four major habitat types were identified within the marina canals: (I) artificial reno mattress (wire baskets filled with rocks); (II) Codium tenue beds; (III) mixed vegetation on sediment; and (IV) barren canal floor. Seahorses were found throughout the marina system with significantly higher densities within the reno mattress habitat. The artificial water body, therefore, has provided suitable habitat for Hippocampus capensis, a noteworthy finding in the current environment of coastal development and the increasing shift from natural to artificial.

  19. Testing the Role of Habitat Isolation among Ecologically Divergent Gall Wasp Populations

    Directory of Open Access Journals (Sweden)

    Scott P. Egan

    2012-01-01

    Full Text Available Habitat isolation occurs when habitat preferences lower the probability of mating between individuals associated with differing habitats. While a potential barrier to gene flow during ecological speciation, the effect of habitat isolation on reproductive isolation has rarely been directly tested. Herein, we first estimated habitat preference for each of six populations of the gall wasp Belonocnema treatae inhabiting either Quercus virginiana or Q. geminata. We then estimated the importance of habitat isolation in generating reproductive isolation between B. treatae populations that were host specific to either Q. virginiana or Q. geminata by measuring mate preference in the presence and absence of the respective host plants. All populations exhibited host preference for their native plant, and assortative mating increased significantly in the presence of the respective host plants. This host-plant-mediated assortative mating demonstrates that habitat isolation likely plays an important role in promoting reproductive isolation among populations of this host-specific gall former.

  20. Columbia County Habitat for Humanity Passive Townhomes

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2016-03-01

    Columbia County Habitat for Humanity (CCHH) (New York, Climate Zone 5A) built a pair of townhomes to Passive House Institute U.S. (PHIUS+ 2015) criteria to explore approaches for achieving Passive House performance (specifically with respect to exterior wall, space-conditioning, and ventilation strategies) within the labor and budget context inherent in a Habitat for Humanity project. CCHH’s goal is to eventually develop a cost-justified Passive House prototype design for future projects.

  1. Teaching Animal Habitat Selection Using Wildlife Tracking Equipment

    Science.gov (United States)

    Laskowski, Jessica; Gillespie, Caitlyn; Corral, Lucia; Oden, Amy; Fricke, Kent; Fontaine, Joseph J.

    2016-01-01

    We present a hands-on outdoor activity coupled with classroom discussion to teach students about wildlife habitat selection, the process by which animals choose where to live. By selecting locations or habitats with many benefits (e.g., food, shelter, mates) and few costs (e.g., predators), animals improve their ability to survive and reproduce.…

  2. Fisheries and Oceans Canada - habitat management program in Ontario

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    On May 5, 2011, the Ontario Waterpower Association hosted the emergent hydro workshop in Peterborough. In the course of the workshop, Fisheries and Oceans Canada presented the habitat management program in Ontario. Fisheries and Oceans Canada explained that their role is to protect water resources. The Fisheries Act was passed to manage fisheries and fish habitats in Canada and to protect them from harmful alteration, disruption or destruction. The policy for the management of fish was written to interpret the Fisheries Act and enhance the productive capacity of fish habitats. In addition, two other Acts were passed, the Species at Risk Act and the Canadian Environmental Assessment Act, designed to protect species from extinction and improve coordination of, and public access to EA information. This presentation highlighted the different existing policies aimed at protecting fisheries and fish habitats in Canada.

  3. Komunitas serangga pada tanaman orok-Orok (Crotalaria striata di berbagai habitat

    Directory of Open Access Journals (Sweden)

    Hasmiandy Hamid

    2017-02-01

    Full Text Available To study insect community at orok-orok plantation (Crotalaria striata from different habitat, we observed insects that interacted with Crotalaria plantation. There were four habitat type that used in this research, habitat open area and others were agroforestry habitat. We counted about nine ordo from insect that interacted with Crotalaria plant. More than 70% member of ordo, include to Hymenoptera, specially Formicidae. Not all function member of the ordo that known, but some of them are pollinator, parasitoid, predator and herbivore.

  4. Stream habitat structure influences macroinvertebrate response to pesticides

    International Nuclear Information System (INIS)

    Rasmussen, Jes Jessen; Wiberg-Larsen, Peter; Baattrup-Pedersen, Annette; Friberg, Nikolai; Kronvang, Brian

    2012-01-01

    Agricultural pesticides continue to impair surface water ecosystems, although there are few assessments of interactions with other modifications such as fine sediment and physical alteration for flood drainage. We, therefore, surveyed pesticide contamination and macroinvertebrates in 14 streams along a gradient of expected pesticide exposure using a paired-reach approach to differentiate effects between physically modified and less modified sites. Apparent pesticides effects on the relative abundance of SPEcies At Risk (SPEAR) were increased at sites with degraded habitats primarily due to the absence of species with specific preferences for hard substrates. Our findings highlight the importance of physical habitat degradation in the assessment and mitigation of pesticide risk in agricultural streams. - Highlights: ► %SPEAR abundance significantly decreased with increasing TU (D. magna). ► %SPEAR abundance was significantly lower when soft sediment was dominant. ► Species specific habitat preferences influenced the total effect of pesticides. ► This study has strong implications for future stream management and risk assessment. - Ecological impacts of pesticides on stream macroinvertebrates are influenced by the heterogeneity and physical structure of micro-habitats.

  5. Idaho Habitat Evaluation for Off-Site Mitigation Record : Annual Report 1987.

    Energy Technology Data Exchange (ETDEWEB)

    Petrosky, Charles E.; Holubetz, Terry B. (Idaho Dept. of Fish and Game, Boise, ID (USA)

    1988-04-01

    The Idaho Department of Fish and Game has been monitoring and evaluating existing and proposed habitat improvement projects for steelhead (Salmo gairdneri) and chinook salmon (Oncorhynchus tshawytscha) in the Clearwater and Salmon River drainages over the last four years. Projects included in the evaluation are funded by, or proposed for funding by, the Bonneville Power Administration (BPA) under the Northwest Power Planning Act as off-site mitigation for downstream hydropower development on the Snake and Columbia rivers. A mitigation record is being developed to use increased smolt production at full seeding as the best measure of benefit from a habitat enhancement project. Determination of full benefit from a project depends on presence of adequate numbers of fish to document actual increases in fish production. The depressed nature of upriver anadromous stocks have precluded attainment of full benefit of any habitat project in Idaho. Partial benefit will be credited to the mitigation record in the interim period of run restoration. According to the BPA Work Plan, project implementors have the primary responsibility for measuring physical habitat and estimating habitat change. To date, Idaho habitat projects have been implemented primarily by the US Forest Service (USFS). The Shoshone-Bannock Tribes (SBT) have sponsored three projects (Bear Valley Mine, Yankee Fork, and the proposed East Fork Salmon River projects). IDFG implemented two barrier-removal projects (Johnson Creek and Boulder Creek) that the USFS was unable to sponsor at that time. The role of IDFG in physical habitat monitoring is primarily to link habitat quality and habitat change to changes in actual, or potential, fish production. Individual papers were processed separately for the data base.

  6. Scale-dependent seasonal pool habitat use by sympatric Wild Brook Trout and Brown Trout populations

    Science.gov (United States)

    Davis, Lori A.; Wagner, Tyler

    2016-01-01

    Sympatric populations of native Brook Trout Salvelinus fontinalis and naturalized Brown Trout Salmo truttaexist throughout the eastern USA. An understanding of habitat use by sympatric populations is of importance for fisheries management agencies because of the close association between habitat and population dynamics. Moreover, habitat use by stream-dwelling salmonids may be further complicated by several factors, including the potential for fish to display scale-dependent habitat use. Discrete-choice models were used to (1) evaluate fall and early winter daytime habitat use by sympatric Brook Trout and Brown Trout populations based on available residual pool habitat within a stream network and (2) assess the sensitivity of inferred habitat use to changes in the spatial scale of the assumed available habitat. Trout exhibited an overall preference for pool habitats over nonpool habitats; however, the use of pools was nonlinear over time. Brook Trout displayed a greater preference for deep residual pool habitats than for shallow pool and nonpool habitats, whereas Brown Trout selected for all pool habitat categories similarly. Habitat use by both species was found to be scale dependent. At the smallest spatial scale (50 m), habitat use was primarily related to the time of year and fish weight. However, at larger spatial scales (250 and 450 m), habitat use varied over time according to the study stream in which a fish was located. Scale-dependent relationships in seasonal habitat use by Brook Trout and Brown Trout highlight the importance of considering scale when attempting to make inferences about habitat use; fisheries managers may want to consider identifying the appropriate spatial scale when devising actions to restore and protect Brook Trout populations and their habitats.

  7. Life stage and species identity affect whether habitat subsidies enhance or simply redistribute consumer biomass.

    Science.gov (United States)

    Keller, Danielle A; Gittman, Rachel K; Bouchillon, Rachel K; Fodrie, F Joel

    2017-10-01

    Quantifying the response of mobile consumers to changes in habitat availability is essential for determining the degree to which population-level productivity is habitat limited rather than regulated by other, potentially density-independent factors. Over landscape scales, this can be explored by monitoring changes in density and foraging as habitat availability varies. As habitat availability increases, densities may: (1) decrease (unit-area production decreases; weak habitat limitation); (2) remain stable (unit-area production remains stable; habitat limitation) or (3) increase (unit-area production increases; strong habitat limitation). We tested the response of mobile estuarine consumers over 5 months to changes in habitat availability in situ by comparing densities and feeding rates on artificial reefs that were or were not adjacent to neighbouring artificial reefs or nearby natural reefs. Using either constructed or natural reefs to manipulate habitat availability, we documented threefold density decreases among juvenile stone crabs as habitat increased (i.e. weak habitat imitation). However, for adult stone crabs, density remained stable across treatments, demonstrating that habitat limitation presents a bottleneck in this species' later life history. Oyster toadfish densities also did not change with increasing habitat availability (i.e. habitat limitation), but densities of other cryptic fishes decreased as habitat availability increased (i.e. weak limitation). Feeding and abundance data suggested that some mobile fishes experience habitat limitation, or, potentially in one case, strong limitation across our habitat manipulations. These findings of significant, community-level habitat limitation provide insight into how global declines in structurally complex estuarine habitats may have reduced the fishery production of coastal ecosystems. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.

  8. Spatiotemporal patterns and habitat associations of smallmouth bass (Micropterus dolomieu) invading salmon-rearing habitat

    Science.gov (United States)

    Lawrence, David J.; Olden, Julian D.; Torgersen, Christian E.

    2012-01-01

    1. Smallmouth bass (Micropterus dolomieu) have been widely introduced to fresh waters throughout the world to promote recreational fishing opportunities. In the Pacific Northwest (U.S.A.), upstream range expansions of predatory bass, especially into subyearling salmon-rearing grounds, are of increasing conservation concern, yet have received little scientific inquiry. Understanding the habitat characteristics that influence bass distribution and the timing and extent of bass and salmon overlap will facilitate the development of management strategies that mitigate potential ecological impacts of bass.2. We employed a spatially continuous sampling design to determine the extent of bass and subyearling Chinook salmon (Oncorhynchus tshawytscha) sympatry in the North Fork John Day River (NFJDR), a free-flowing river system in the Columbia River Basin that contains an upstream expanding population of non-native bass. Extensive (i.e. 53 km) surveys were conducted over 2 years and during an early and late summer period of each year, because these seasons provide a strong contrast in the river’s water temperature and flow condition. Classification and regression trees were applied to determine the primary habitat correlates of bass abundance at reach and channel-unit scales.3. Our study revealed that bass seasonally occupy up to 22% of the length of the mainstem NFJDR where subyearling Chinook salmon occur, and the primary period of sympatry between these species was in the early summer and not during peak water temperatures in late summer. Where these species co-occurred, bass occupied 60–76% of channel units used by subyearling Chinook salmon in the early summer and 28–46% of the channel units they occupied in the late summer. Because these rearing salmon were well below the gape limitation of bass, this overlap could result in either direct predation or sublethal effects of bass on subyearling Chinook salmon. The upstream extent of bass increased 10–23

  9. Field review of fish habitat improvement projects in central Idaho

    International Nuclear Information System (INIS)

    Beschta, R.L.; Griffith, J.; Wesche, T.A.

    1993-05-01

    The goal of this field review was to provide information to the Bonneville Power Administration (BPA) regarding previous and ongoing fish habitat improvement projects in central Idaho. On July 14, 1992, the review team met at the Sawtooth National Recreation Area office near Ketchum, Idaho, for a slide presentation illustrating several habitat projects during their construction phases. Following the slide presentation, the review team inspected fish habitat projects that have been implemented in the last several years in the Stanley Basin and adjacent valleys. At each site the habitat project was described to the field team and a brief period for project inspection followed. The review team visited approximately a dozen sites on the Challis, Sawtooth, and Boise National Forests over a period of approximately two and a half days. There are two objectives of this review namely to summarize observations for specific field sites and to provide overview commentary regarding the BPA habitat improvement program in central Idaho

  10. Linking occurrence and fitness to persistence: Habitat-based approach for endangered Greater Sage-Grouse

    Science.gov (United States)

    Aldridge, Cameron L.; Boyce, Mark S.

    2007-01-01

    Detailed empirical models predicting both species occurrence and fitness across a landscape are necessary to understand processes related to population persistence. Failure to consider both occurrence and fitness may result in incorrect assessments of habitat importance leading to inappropriate management strategies. We took a two-stage approach to identifying critical nesting and brood-rearing habitat for the endangered Greater Sage-Grouse (Centrocercus urophasianus) in Alberta at a landscape scale. First, we used logistic regression to develop spatial models predicting the relative probability of use (occurrence) for Sage-Grouse nests and broods. Secondly, we used Cox proportional hazards survival models to identify the most risky habitats across the landscape. We combined these two approaches to identify Sage-Grouse habitats that pose minimal risk of failure (source habitats) and attractive sink habitats that pose increased risk (ecological traps). Our models showed that Sage-Grouse select for heterogeneous patches of moderate sagebrush cover (quadratic relationship) and avoid anthropogenic edge habitat for nesting. Nests were more successful in heterogeneous habitats, but nest success was independent of anthropogenic features. Similarly, broods selected heterogeneous high-productivity habitats with sagebrush while avoiding human developments, cultivated cropland, and high densities of oil wells. Chick mortalities tended to occur in proximity to oil and gas developments and along riparian habitats. For nests and broods, respectively, approximately 10% and 5% of the study area was considered source habitat, whereas 19% and 15% of habitat was attractive sink habitat. Limited source habitats appear to be the main reason for poor nest success (39%) and low chick survival (12%). Our habitat models identify areas of protection priority and areas that require immediate management attention to enhance recruitment to secure the viability of this population. This novel

  11. Chinook salmon use of spawning patches: relative roles of habitat quality, size, and connectivity.

    Science.gov (United States)

    Isaak, Daniel J; Thurow, Russell F; Rieman, Bruce E; Dunham, Jason B

    2007-03-01

    Declines in many native fish populations have led to reassessments of management goals and shifted priorities from consumptive uses to species preservation. As management has shifted, relevant environmental characteristics have evolved from traditional metrics that described local habitat quality to characterizations of habitat size and connectivity. Despite the implications this shift has for how habitats may be prioritized for conservation, it has been rare to assess the relative importance of these habitat components. We used an information-theoretic approach to select the best models from sets of logistic regressions that linked habitat quality, size, and connectivity to the occurrence of chinook salmon (Oncorhynchus tshawytscha) nests. Spawning distributions were censused annually from 1995 to 2004, and data were complemented with field measurements that described habitat quality in 43 suitable spawning patches across a stream network that drained 1150 km2 in central Idaho. Results indicated that the most plausible models were dominated by measures of habitat size and connectivity, whereas habitat quality was of minor importance. Connectivity was the strongest predictor of nest occurrence, but connectivity interacted with habitat size, which became relatively more important when populations were reduced. Comparison of observed nest distributions to null model predictions confirmed that the habitat size association was driven by a biological mechanism when populations were small, but this association may have been an area-related sampling artifact at higher abundances. The implications for habitat management are that the size and connectivity of existing habitat networks should be maintained whenever possible. In situations where habitat restoration is occurring, expansion of existing areas or creation of new habitats in key areas that increase connectivity may be beneficial. Information about habitat size and connectivity also could be used to strategically

  12. Selection of nest-site habitat by interior least terns in relation to sandbar construction

    Science.gov (United States)

    Sherfy, Mark H.; Stucker, Jennifer H.; Buhl, Deborah A.

    2012-01-01

    Federally endangered interior least terns (Sternula antillarum) nest on bare or sparsely vegetated sandbars on midcontinent river systems. Loss of nesting habitat has been implicated as a cause of population declines, and managing these habitats is a major initiative in population recovery. One such initiative involves construction of mid-channel sandbars on the Missouri River, where natural sandbar habitat has declined in quantity and quality since the late 1990s. We evaluated nest-site habitat selection by least terns on constructed and natural sandbars by comparing vegetation, substrate, and debris variables at nest sites (n = 798) and random points (n = 1,113) in bare or sparsely vegetated habitats. Our logistic regression models revealed that a broader suite of habitat features was important in nest-site selection on constructed than on natural sandbars. Odds ratios for habitat variables indicated that avoidance of habitat features was the dominant nest-site selection process on both sandbar types, with nesting terns being attracted to nest-site habitat features (gravel and debris) and avoiding vegetation only on constructed sandbars, and avoiding silt and leaf litter on both sandbar types. Despite the seemingly uniform nature of these habitats, our results suggest that a complex suite of habitat features influences nest-site choice by least terns. However, nest-site selection in this social, colonially nesting species may be influenced by other factors, including spatial arrangement of bare sand habitat, proximity to other least terns, and prior habitat occupancy by piping plovers (Charadrius melodus). We found that nest-site selection was sensitive to subtle variation in habitat features, suggesting that rigor in maintaining habitat condition will be necessary in managing sandbars for the benefit of least terns. Further, management strategies that reduce habitat features that are avoided by least terns may be the most beneficial to nesting least terns.

  13. Habitat Evaluation Procedures (HEP) Report; Upper Trimble Project, Technical Report 2004-2005.

    Energy Technology Data Exchange (ETDEWEB)

    Entz, Ray

    2005-02-01

    On July 13, 2004, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the Upper Trimble property, an acquisition completed by the Kalispel Tribe of Indians in March 2004. Evaluation species and appropriate models include bald eagle, black-capped chickadee, Canada goose, mallard, muskrat, yellow warbler, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The Upper Trimble Project provides a total of 250.67 Habitat Units (HUs) for the species evaluated. Wet meadow provides 136.92 HUs for mallard, muskrat, and Canada goose. Mixed forest habitat provides 111.88 HUs for bald eagle, black-capped chickadee, mallard, and white-tailed deer. Scrub-shrub vegetation provides 1.87 HUs for yellow warbler, and white-tailed deer. The objective of using HEP at the Upper Trimble Project and other protected properties is to document the quality and quantity of available habitat for selected wildlife species. In this way, HEP provides information on the relative value of the same area at future points in time so that the effect of management activities on wildlife habitat can be quantified. When combined with other tools, the baseline HEP will be used to determine the most effective on-site management, restoration, and enhancement actions to increase habitat suitability for targeted species. The same process will be replicated every five years to quantitatively evaluate the effectiveness of management strategies in improving and maintaining habitat conditions while providing additional crediting to BPA for enhanced habitat values.

  14. Individual variation in habitat use in two stream fish assemblages

    OpenAIRE

    Luisa Resende Manna; Carla Ferreira Rezende

    2015-01-01

    The habitat use is an individual choice that is influenced by physical conditions such as substrate type, food resources availability and adequate depth. However, habitat use is often measured only through interspecific variability because intraspecific variability is supposed to be low. Here, the differences in habitat use by two stream fish assemblages in two different environments (Brazilian rainforest and semiarid) were investigated at both interspecific and intraspecific levels. We perfo...

  15. Habitat Complexity in Aquatic Microcosms Affects Processes Driven by Detritivores.

    Directory of Open Access Journals (Sweden)

    Lorea Flores

    Full Text Available Habitat complexity can influence predation rates (e.g. by providing refuge but other ecosystem processes and species interactions might also be modulated by the properties of habitat structure. Here, we focussed on how complexity of artificial habitat (plastic plants, in microcosms, influenced short-term processes driven by three aquatic detritivores. The effects of habitat complexity on leaf decomposition, production of fine organic matter and pH levels were explored by measuring complexity in three ways: 1. as the presence vs. absence of habitat structure; 2. as the amount of structure (3 or 4.5 g of plastic plants; and 3. as the spatial configuration of structures (measured as fractal dimension. The experiment also addressed potential interactions among the consumers by running all possible species combinations. In the experimental microcosms, habitat complexity influenced how species performed, especially when comparing structure present vs. structure absent. Treatments with structure showed higher fine particulate matter production and lower pH compared to treatments without structures and this was probably due to higher digestion and respiration when structures were present. When we explored the effects of the different complexity levels, we found that the amount of structure added explained more than the fractal dimension of the structures. We give a detailed overview of the experimental design, statistical models and R codes, because our statistical analysis can be applied to other study systems (and disciplines such as restoration ecology. We further make suggestions of how to optimise statistical power when artificially assembling, and analysing, 'habitat complexity' by not confounding complexity with the amount of structure added. In summary, this study highlights the importance of habitat complexity for energy flow and the maintenance of ecosystem processes in aquatic ecosystems.

  16. Marine habitat mapping of the Milford Haven Waterway, Wales, UK: Comparison of facies mapping and EUNIS classification for monitoring sediment habitats in an industrialized estuary

    Science.gov (United States)

    Carey, Drew A.; Hayn, Melanie; Germano, Joseph D.; Little, David I.; Bullimore, Blaise

    2015-06-01

    A detailed map and dataset of sedimentary habitats of the Milford Haven Waterway (MHW) was compiled for the Milford Haven Waterway Environmental Surveillance Group (MHWESG) from seafloor images collected in May, 2012 using sediment-profile and plan-view imaging (SPI/PV) survey techniques. This is the most comprehensive synoptic assessment of sediment distribution and benthic habitat composition available for the MHW, with 559 stations covering over 40 km2 of subtidal habitats. In the context of the MHW, an interpretative framework was developed that classified each station within a 'facies' that included information on the location within the waterway and inferred sedimentary and biological processes. The facies approach provides critical information on landscape-scale habitats including relative location and inferred sediment transport processes and can be used to direct future monitoring activities within the MHW and to predict areas of greatest potential risk from contaminant transport. Intertidal sediment 'facies' maps have been compiled in the past for MHW; this approach was expanded to map the subtidal portions of the waterway. Because sediment facies can be projected over larger areas than individual samples (due to assumptions based on physiography, or landforms) they represent an observational model of the distribution of sediments in an estuary. This model can be tested over time and space through comparison with additional past or future sample results. This approach provides a means to evaluate stability or change in the physical and biological conditions of the estuarine system. Initial comparison with past results for intertidal facies mapping and grain size analysis from grab samples showed remarkable stability over time for the MHW. The results of the SPI/PV mapping effort were cross-walked to the European Nature Information System (EUNIS) classification to provide a comparison of locally derived habitat mapping with European-standard habitat

  17. Life on the rocks: habitat use drives morphological and performance evolution in lizards.

    Science.gov (United States)

    Goodman, Brett A; Miles, Donald B; Schwarzkopf, Lin

    2008-12-01

    As a group, lizards occupy a vast array of habitats worldwide, yet there remain relatively few cases where habitat use (ecology), morphology, and thus, performance, are clearly related. The best known examples include: increased limb length in response to increased arboreal perch diameter in anoles and increased limb length in response to increased habitat openness for some skinks. Rocky habitats impose strong natural selection on specific morphological characteristics, which differs from that imposed on terrestrial species, because moving about on inclined substrates of irregular sizes and shapes constrains locomotor performance in predictable ways. We quantified habitat use, morphology, and performance of 19 species of lizards (family Scincidae, subfamily Lygosominae) from 23 populations in tropical Australia. These species use habitats with considerable variation in rock availability. Comparative phylogenetic analyses revealed that occupation of rock-dominated habitats correlated with the evolution of increased limb length, compared to species from forest habitats that predominantly occupied leaf litter. Moreover, increased limb length directly affected performance, with species from rocky habitats having greater sprinting, climbing, and clinging ability than their relatives from less rocky habitats. Thus, we found that the degree of rock use is correlated with both morphological and performance evolution in this group of tropical lizards.

  18. The fate of threatened coastal dune habitats in Italy under climate change scenarios.

    Science.gov (United States)

    Prisco, Irene; Carboni, Marta; Acosta, Alicia T R

    2013-01-01

    Coastal dunes worldwide harbor threatened habitats characterized by high diversity in terms of plant communities. In Italy, recent assessments have highlighted the insufficient state of conservation of these habitats as defined by the EU Habitats Directive. The effects of predicted climate change could have dramatic consequences for coastal environments in the near future. An assessment of the efficacy of protection measures under climate change is thus a priority. Here, we have developed environmental envelope models for the most widespread dune habitats in Italy, following two complementary approaches: an "indirect" plant-species-based one and a simple "direct" one. We analyzed how habitats distribution will be altered under the effects of two climate change scenarios and evaluated if the current Italian network of protected areas will be effective in the future after distribution shifts. While modeling dune habitats with the "direct" approach was unsatisfactory, "indirect" models had a good predictive performance, highlighting the importance of using species' responses to climate change for modeling these habitats. The results showed that habitats closer to the sea may even increase their geographical distribution in the near future. The transition dune habitat is projected to remain stable, although mobile and fixed dune habitats are projected to lose most of their actual geographical distribution, the latter being more sensitive to climate change effects. Gap analysis highlighted that the habitats' distribution is currently adequately covered by protected areas, achieving the conservation target. However, according to predictions, protection level for mobile and fixed dune habitats is predicted to drop drastically under the climate change scenarios which we examined. Our results provide useful insights for setting management priorities and better addressing conservation efforts to preserve these threatened habitats in future.

  19. Umatilla River Basin Anadromous Fish Habitat Enhancement Project : 1993 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, R. Todd

    1993-04-01

    The Umatilla Basin Anadromous Fish Habitat Enhancement Project is funded under the Northwest Power Planning Council's Columbia River Basin Fish and Wildlife Program Measure 704 (d) (1) 34.02 and targets the improvement of water quality and restoration of riparian areas, holding, spawning and rearing habitats of steelhead, spring and fall chinook and coho salmon. The project focused on implementing instream and riparian habitat improvements on private lands on the Umatilla Indian Reservation (hereafter referred to as Reservation) from April 1, 1988 to March 31, 1992. These efforts resulted in enhancement of the lower 1/4 mile of Boston Canyon Creek, the lower 4 river miles of Meacham Creek and 3.2 river miles of the Umatilla River (downstream of the Meacham Creek confluence upstream to the Reservation East Boundary). In 1993, the project shifted emphasis to a comprehensive watershed approach consistent with other basin efforts and began to identify upland and riparian watershed-wide causative factors impacting fisheries habitat and natural fisheries production capabilities throughout the Umatilla River Watershed. Maintenance of existing habitat improvement projects was included under this comprehensive approach. Maintenance of existing gravel traps, instream and bank stabilization structures was required within project areas during the reporting period due to spring flooding damage and high bedload movement. Maintenance activities were completed between river mile (RM) 0.0 and RM 0.25 Boston Canyon Creek, between RM 0.0 and RM 4 Meacham Creek and between RM 78.5 and RM 79 Umatilla River. Habitat enhancement areas were seeded with native grass, legume, shrub and wildflower mixes and planted with willow cuttings to assist in floodplain recovery, stream channel stability and filtering of sediments during high flow periods. Water quality monitoring continued for temperature and turbidity throughout the upper Umatilla River Watershed. Survey of cross sections and

  20. Body size distribution demonstrates flexible habitat shift of green turtle (Chelonia mydas

    Directory of Open Access Journals (Sweden)

    Ryota Hayashi

    2015-01-01

    Full Text Available Green turtles (Chelonia mydas, listed as Endangered on the IUCN redlist, have a broad migration area and undergo a habitat shift from the pelagic (hatchling to neritic (growth zones. We studied habitat utilisation of the coastal feeding grounds around Okinawajima Island, Japan, in 103 green turtles. The western and eastern turtle aggregations off Okinawa had homogeneous genetic compositions, but different body size distributions. The western coastal feeding ground supported larger individuals than the eastern coastal feeding ground. Thus, green turtles appear to prefer different feeding grounds during their growth, and have a flexible habitat shift including a secondary habitat shift from east to west around Okinawajima Island after they are recruited to the coastal habitats. This study suggests maintaining coastal habitat diversity is important for green turtle conservation.

  1. Seedling stage strategies as a means of habitat specialization in herbaceous plants

    DEFF Research Database (Denmark)

    ten Brink, Dirk-Jan; Bruun, Hans Henrik

    2011-01-01

    The regeneration niche has been little investigated in studies of community assembly and plant distribution. We examined adaptive associations between seedling traits and habitat specialization. Two habitat contrasts were investigated across several evolutionary lineages of angiosperms: species...... specialized to forest vs. open habitats and to dry vs. wet habitats. We also tested whether effects of shade and drought vary independently or, alternatively, if shade may amplify effects on drought-stressed plants. Seedling response in terms of growth rate, height, slenderness, specific leaf area (SLA......) and degree of elongation (longest internode; petiole or leaf-sheath depending on species' morphology) to light and watering treatments was assessed. We used a factorial design involving three light regimes and two watering frequencies. The open-shaded habitat contrast and the dry-wet habitat contrast were...

  2. Habitat Evaluation Procedures (HEP) Report : Rainwater Wildlife Area, 1998-2001 Technical Report.

    Energy Technology Data Exchange (ETDEWEB)

    Childs, Allen

    2004-01-01

    The 8,768 acre Rainwater Wildlife Area was acquired in September 1998 by the Confederated Tribes of the Umatilla Indian Reservation (CTUIR) through an agreement with Bonneville Power Administration (BPA) to partially offset habitat losses associated with construction of the John Day and McNary hydroelectric facilities on the mainstem Columbia River. U.S. Fish and Wildlife Service (USFWS) Habitat Evaluation Procedures (HEP) were used to determine the number of habitat units credited to BPA for acquired lands. Upland and riparian forest, upland and riparian shrub, and grassland rover types are evaluated in this study. Targeted wildlife species include downy woodpecker (Picoides pubescens), black-capped chickadee (Parus atricopillus), blue grouse (Dendragapus obscurus), great blue heron (Ardea herodias), yellow warbler (Dendroica petechia), mink (Mustela vison), and Western meadowlark (Sturnella neglects). Habitat surveys were conducted in 1998 and 1999 in accordance with published HEP protocols and included 65,300, 594m{sup 2} plots, and 112 one-tenth-acre plots. Between 153.3 and 7,187.46 acres were evaluated for each target wildlife mitigation species. Derived habitat suitability indices were multiplied by corresponding cover-type acreages to determine the number of habitat units for each species. The total baseline habitat units credited to BPA for the Rainwater Wildlife Area and its seven target species is 5,185.3 habitat units. Factors limiting habitat suitability are related to the direct, indirect, and cumulative effects of past livestock grazing, road construction, and timber harvest which have simplified the structure, composition, and diversity of native plant communities. Alternatives for protecting and improving habitat suitability include exclusion of livestock grazing, road de-commissioning/obliteration, reforestation and thinning, control of competing and unwanted vegetation (including noxious weeds), reestablishing displaced or reduced native

  3. Protecting Marine Biodiversity: A Comparison of Individual Habitat Quotas (IHQs) and Marine Protected Areas

    OpenAIRE

    Kurt Schnier; Dan Holland

    2005-01-01

    Fisheries managers in the United States are required to identify and mitigate the adverse impacts of fishing activity on essential fish habitat (EFH). There are additional concerns that the viability of noncommercial species, animals that are habitat dependent and/or are themselves constituents of fishery habitat may still be threatened. We consider a cap-and-trade system for habitat conservation, individual habitat quotas for fisheries, to achieve habitat conservation and species protection ...

  4. The Earth Observation Data for Habitat Monitoring (EODHaM) system

    Science.gov (United States)

    Lucas, Richard; Blonda, Palma; Bunting, Peter; Jones, Gwawr; Inglada, Jordi; Arias, Marcela; Kosmidou, Vasiliki; Petrou, Zisis I.; Manakos, Ioannis; Adamo, Maria; Charnock, Rebecca; Tarantino, Cristina; Mücher, Caspar A.; Jongman, Rob H. G.; Kramer, Henk; Arvor, Damien; Honrado, Joāo Pradinho; Mairota, Paola

    2015-05-01

    To support decisions relating to the use and conservation of protected areas and surrounds, the EU-funded BIOdiversity multi-SOurce monitoring System: from Space TO Species (BIO_SOS) project has developed the Earth Observation Data for HAbitat Monitoring (EODHaM) system for consistent mapping and monitoring of biodiversity. The EODHaM approach has adopted the Food and Agriculture Organization Land Cover Classification System (LCCS) taxonomy and translates mapped classes to General Habitat Categories (GHCs) from which Annex I habitats (EU Habitats Directive) can be defined. The EODHaM system uses a combination of pixel and object-based procedures. The 1st and 2nd stages use earth observation (EO) data alone with expert knowledge to generate classes according to the LCCS taxonomy (Levels 1 to 3 and beyond). The 3rd stage translates the final LCCS classes into GHCs from which Annex I habitat type maps are derived. An additional module quantifies changes in the LCCS classes and their components, indices derived from earth observation, object sizes and dimensions and the translated habitat maps (i.e., GHCs or Annex I). Examples are provided of the application of EODHaM system elements to protected sites and their surrounds in Italy, Wales (UK), the Netherlands, Greece, Portugal and India.

  5. A habitat assessment for Florida panther population expansion into central Florida

    Science.gov (United States)

    Thatcher, C.A.; Van Manen, F.T.; Clark, J.D.

    2009-01-01

    One of the goals of the Florida panther (Puma concolor coryi) recovery plan is to expand panther range north of the Caloosahatchee River in central Florida. Our objective was to evaluate the potential of that region to support panthers. We used a geographic information system and the Mahalanobis distance statistic to develop a habitat model based on landscape characteristics associated with panther home ranges. We used cross-validation and an independent telemetry data set to test the habitat model. We also conducted a least-cost path analysis to identify potential habitat linkages and to provide a relative measure of connectivity among habitat patches. Variables in our model were paved road density, major highways, human population density, percentage of the area permanently or semipermanently flooded, and percentage of the area in natural land cover. Our model clearly identified habitat typical of that found within panther home ranges based on model testing with recent telemetry data. We identified 4 potential translocation sites that may support a total of approximately 36 panthers. Although we identified potential habitat linkages, our least-cost path analyses highlighted the extreme isolation of panther habitat in portions of the study area. Human intervention will likely be required if the goal is to establish female panthers north of the Caloosahatchee in the near term.

  6. Maladaptive habitat selection of a migratory passerine bird in a human-modified landscape.

    Directory of Open Access Journals (Sweden)

    Franck A Hollander

    Full Text Available In human-altered environments, organisms may preferentially settle in poor-quality habitats where fitness returns are lower relative to available higher-quality habitats. Such ecological trapping is due to a mismatch between the cues used during habitat selection and the habitat quality. Maladaptive settlement decisions may occur when organisms are time-constrained and have to rapidly evaluate habitat quality based on incomplete knowledge of the resources and conditions that will be available later in the season. During a three-year study, we examined settlement decision-making in the long-distance migratory, open-habitat bird, the Red-backed shrike (Lanius collurio, as a response to recent land-use changes. In Northwest Europe, the shrikes typically breed in open areas under a management regime of extensive farming. In recent decades, Spruce forests have been increasingly managed with large-size cutblocks in even-aged plantations, thereby producing early-successional vegetation areas that are also colonised by the species. Farmland and open areas in forests create mosaics of two different types of habitats that are now occupied by the shrikes. We examined redundant measures of habitat preference (order of settlement after migration and distribution of dominant individuals and several reproductive performance parameters in both habitat types to investigate whether habitat preference is in line with habitat quality. Territorial males exhibited a clear preference for the recently created open areas in forests with higher-quality males settling in this habitat type earlier. Reproductive performance was, however, higher in farmland, with higher nest success, offspring quantity, and quality compared to open areas in forests. The results showed strong among-year consistency and we can therefore exclude a transient situation. This study demonstrates a case of maladaptive habitat selection in a farmland bird expanding its breeding range to human

  7. Reptile habitat preference in heathland: implications for heathland management

    NARCIS (Netherlands)

    Stumpel, A.H.P.; Werf, van der D.C.

    2012-01-01

    A two-year reptile survey was conducted in a heathland in the north of the Netherlands, using artificial refuges placed in different habitats. The studied habitats differed in their botanical composition and physical structure. Five reptile species were recorded: slow worm (Anguis fragilis),

  8. Marine nurseries and effective juvenile habitats: concepts and applications.

    NARCIS (Netherlands)

    Dahlgren, C.P.; Kellison, G.T.; Adams, A.J.; Gillanders, B.M.; Kendall, M.S.; Layman, C.A.; Ley, J.A.; Nagelkerken, I.; Serafy, J.E.

    2006-01-01

    Much recent attention has been focused on juvenile fish and invertebrate habitat use, particularly defining and identifying marine nurseries. The most significant advancement in this area has been the development of a standardized framework for assessing the relative importance of juvenile habitats

  9. Conserving the Connections: A Nationwide Inventory of State-Based Habitat Connectivity Analysis

    OpenAIRE

    Feinberg, Jesse

    2007-01-01

    Habitat fragmentation is among the most serious threats to species and biological diversity. Highways can divide wildlife habitat into smaller patches, reducing or prohibiting necessary wildlife movement between core habitat areas for foraging, mating, and other life functions. Defenders of Wildlife reviewed all 50 states to identify those that are working to address habitat connectivity in the context of transportation planning. The goal of these plans is to facilitate interagency c...

  10. Chroniques d'habitat et dynamique de populations de truite

    Directory of Open Access Journals (Sweden)

    CAPRA H.

    1995-04-01

    Full Text Available Une nouvelle méthode a permis de quantifier des Durées Continues d'Habitat Limitant (méthode DCHL à partir de chroniques d'habitat potentiel, pour la truite fario (Salmo trutta fario, L.. Cette méthode a été appliquée sur deux cours d'eau naturels et sur une station soumise à éclusée. Elle a été validée sur les deux cours d'eau naturels en ce qui concerne l'habitat limitant pour les jeunes truites de l'année (0+. Elle offre un outil pratique d'analyse des périodes d'habitat limitant en régime naturel. En situation d'éclusées, l'interprétation des résultats est différente et nécessite encore un effort important de suivi biologique.

  11. Habitat Management to Suppress Pest Populations: Progress and Prospects.

    Science.gov (United States)

    Gurr, Geoff M; Wratten, Steve D; Landis, Douglas A; You, Minsheng

    2017-01-31

    Habitat management involving manipulation of farmland vegetation can exert direct suppressive effects on pests and promote natural enemies. Advances in theory and practical techniques have allowed habitat management to become an important subdiscipline of pest management. Improved understanding of biodiversity-ecosystem function relationships means that researchers now have a firmer theoretical foundation on which to design habitat management strategies for pest suppression in agricultural systems, including landscape-scale effects. Supporting natural enemies with shelter, nectar, alternative prey/hosts, and pollen (SNAP) has emerged as a major research topic and applied tactic with field tests and adoption often preceded by rigorous laboratory experimentation. As a result, the promise of habitat management is increasingly being realized in the form of practical worldwide implementation. Uptake is facilitated by farmer participation in research and is made more likely by the simultaneous delivery of ecosystem services other than pest suppression.

  12. Encroachment of oriental bittersweet into Pitcher’s thistle habitat

    Science.gov (United States)

    Leicht-Young, Stacey A.; Pavlovic, Noel B.

    2012-01-01

    Common invasive species and rare endemic species can grow and interact at the ecotone between forested and non-forested dune habitats. To investigate these interactions, a comparison of the proximity and community associates of a sympatric invasive (Celastrus orbiculatus; oriental bittersweet) and native (C. scandens; American bittersweet) liana species to federally threatened Cirsium pitcheri (Pitcher's thistle) in the dunes habitats of Lake Michigan was conducted. Overall, the density of the invasive liana species was significantly greater in proximity to C. pitcheri than the native species. On the basis of composition, the three focal species occurred in both foredune and blowout habitats. The plant communities associated with the three focal species overlapped in ordination space, but there were significant differences in composition. The ability of C. orbiculatus to rapidly grow and change the ecological dynamics of invasion sites adds an additional threat to the successional habitats of C. pitcheri.

  13. Habitat association and conservation implications of endangered Francois' langur (Trachypithecus francoisi.

    Directory of Open Access Journals (Sweden)

    Yajie Zeng

    Full Text Available Francois' langur (Trachypithecus francoisi is an endangered primate and endemic to the limestone forests of the tropical and subtropical zone of northern Vietnam and South-west China with a population of about 2,000 individuals. Conservation efforts are hampered by limited knowledge of habitat preference in its main distribution area. We surveyed the distribution of Francois' langur and modeled the relationship between the probability of use and habitat features in Mayanghe National Nature Reserve, Guizhou, China. The main objectives of this study were to provide quantitative information on habitat preference, estimating the availability of suitable habitat, and providing management guidelines for the effective conservation of this species. By comparing 92 used locations with habitat available in the reserve, we found that Francois' langur was mainly distributed along valleys and proportionally, used bamboo forests and mixed conifer-broadleaf forests more than their availability, whereas they tended to avoid shrubby areas and coniferous forests. The langur tended to occur at sites with lower elevation, steeper slope, higher tree canopy density, and a close distance to roads and water. The habitat occupancy probability was best modeled by vegetation type, vegetation coverage, elevation, slope degree, distances to nearest water, paved road, and farmland edge. The suitable habitat in this reserve concentrated in valleys and accounted for about 25% of the total reserve area. Our results showed that Francois' langur was not only restricted at the landscapes level at the regions with karst topography, limestone cliffs, and caves, but it also showed habitat preference at the local scale. Therefore, the protection and restoration of the langur preferred habitats such as mixed conifer-broadleaf forests are important and urgent for the conservation of this declining species.

  14. Malaria vectors in Lake Victoria and adjacent habitats in western Kenya.

    Directory of Open Access Journals (Sweden)

    Noboru Minakawa

    Full Text Available The prevalence of malaria among the residents of the Lake Victoria basin remains high. The environment associated with the lake may maintain a high number of malaria vectors. Lake habitats including water hyacinths have been suspected to be the source of vectors. This study investigated whether malaria vectors breed in the lake habitats and adjacent backwater pools. Anopheline larvae were collected within the littoral zone of the lake and adjacent pools located along approximately 24.3 km of the lakeshore in western Kenya, and their breeding sites characterized. Three primary vector species, Anopheles arabiensis, Anopheles gambiae s.s. and Anopheles funestus s.s., and three potential vectors, were found in the lake habitats. Unexpectedly, An. arabiensis was the most dominant vector species in the lake sampling sites. Its habitats were uncovered or covered with short grass. A potential secondary malaria vector, Anopheles rivulorum, dominated the water hyacinths in the lake. Most breeding sites in the lake were limited to areas that were surrounded by tall emergent plants, including trees, and those not exposed to waves. Nearly half of adjacent habitats were lagoons that were separated from the lake by sand bars. Lagoons contained a variety of microhabitats. Anopheles arabiensis dominated open habitats, whereas An. funestus s.s. was found mainly in vegetated habitats in lagoons. The current study confirmed that several breeding sites are associated with Lake Victoria. Given that Lake Victoria is the second largest lake in the world, the lake related habitats must be extensive; therefore, making targeted vector control difficult. Further exploration is necessary to estimate the effects of lake associated habitats on malaria transmission so as to inform a rational decision-making process for vector control.

  15. Species diversity and qualitative assessment of ground beetles (Coleoptera: Carabidae) in three riparian habitats.

    Science.gov (United States)

    Michels, G J; Carney, V A; Jones, E N; Pollock, D A

    2010-06-01

    In a 3-yr study involving saltcedar-free, saltcedar-infested, and burned habitats in a riparian area at Lake Meredith, TX, the number of carabid species collected, diversity indices, and indicator species varied significantly among habitats. A 3-yr average of 15, 14, and 24 carabid species were collected from the saltcedar-free, saltcedar-infested, and burned habitats, respectively. Values for species richness, Shannon's and Simpson's diversity indices, and evenness index for pooled data collected from 2005 to 2007 were higher in the burned habitat followed by the saltcedar-free habitat and the saltcedar-infested habitat. Within-year parameters across the three habitats generally followed the pooled data results with some variation. Nonmetric multidimensional scaling analyses clearly indicated groups of carabid species preferred specific habitats. Five species in the burned area had indicator species percentage values >50% (Agonum punctiforme, Agonum texanum, Brachinus alternans, Harpalus pensylvanicus, and Poecilus chalcites). In the saltcedar-infested and saltcedar-free habitats, only one species in each habitat had indicator species percentage values that exceeded 50%: Calathus opaculus and Cicindela punctulata punctulata, respectively.

  16. Northwest Montana Wildlife Mitigation Habitat Protection : Advance Design : Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Wood, Marilyn A.

    1993-02-01

    This report summarizes the habitat protection process developed to mitigate for certain wildlife and wildlife habitat losses due to construction of Hungry Horse and Libby dams in northwestern Montana.

  17. Towards a Caribou Habitat Management Strategy for Northwestern Ontario: Running the Gauntlet

    Directory of Open Access Journals (Sweden)

    Gerald D. Racey

    1996-01-01

    Full Text Available A management strategy for woodland caribou (Rangifer tarandus caribou habitat is being developed in northwestern Ontario. This strategy is based upon a set of draft Timber Management Guidelines for the Provision of Woodland Caribou Habitat. These guidelines recommend maintaining a sustainable supply of winter habitat within large tracts of old forest, protecting calving areas and minimizing human disturbance. Due to the large temporal and spatial scale of caribou habitat management, an ecosystem-based approach is recommended. Public response to the strategy shows a strong dichotomy between environmental and utilitarian values among all the major stakeholder groups. The major issues raised by the public include security of industrial wood supply, quality of the knowledge base, level of awareness of caribou, economic impacts on remote communities, concern about environmental impacts and silvicultural know-how. The government is responding to these concerns as the strategy evolves. Current emphasis is placed on increasing awareness of the public, training resource managers in caribou biology, management and habitat planning, implementing interim habitat management prescriptions and studying the potential impact on wood supply. The final direction for a northwestern Ontario strategy to conserve woodland caribou habitat has yet to be decided, although a commitment has been made to strive for the conservation of woodland caribou populations and their habitat.

  18. Pelagic habitat: exploring the concept of good environmental status

    DEFF Research Database (Denmark)

    Dickey-Collas, Mark; McQuatters-Gollop, Abigail; Bresnan, Eileen

    2017-01-01

    Marine environmental legislation is increasingly expressing a need to consider the quality of pelagic habitats. This paper uses the European Union marine strategy framework to explore the concept of good environmental status (GES) of pelagic habitat with the aim to build a wider understanding of ...

  19. Leatherback Sea Turtle Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for leatherback turtle as designated by Federal Register Vol. 44, No. 17711, March 23, 1979, Rules and Regulations....

  20. Hawksbill Sea Turtle Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for hawksbill turtle as designated by Federal Register Vol. 63, No. 46701, September 2, 1998, Rules and Regulations....

  1. Endangered Species Act Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Critical habitat (CH) is designated for the survival and recovery of species listed as threatened or endangered under the Endangered Species Act (ESA). Critical...

  2. Behavioural cues surpass habitat factors in explaining prebreeding resource selection by a migratory diving duck

    Science.gov (United States)

    O'Neil, Shawn T.; Warren, Jeffrey M.; Takekawa, John Y.; De La Cruz, Susan E. W.; Cutting, Kyle A.; Parker, Michael W.; Yee, Julie L.

    2014-01-01

    Prebreeding habitat selection in birds can often be explained in part by habitat characteristics. However, females may also select habitats on the basis of fidelity to areas of previous reproductive success or use by conspecifics. The relative influences of sociobehavioural attributes versus habitat characteristics in habitat selection has been primarily investigated in songbirds, while less is known about how these factors affect habitat selection processes in migratory waterfowl. Animal resource selection models often exhibit much unexplained variation; spatial patterns driven by social and behavioural characteristics may account for some of this. We radiomarked female lesser scaup, Aythya affinis, in the southwestern extent of their breeding range to explore hypotheses regarding relative roles of habitat quality, site fidelity and conspecific density in prebreeding habitat selection. We used linear mixed-effects models to relate intensity of use within female home ranges to habitat features, distance to areas of reproductive success during the previous breeding season and conspecific density. Home range habitats included shallow water (≤118 cm), moderate to high densities of flooded emergent vegetation/open water edge and open water areas with submerged aquatic vegetation. Compared with habitat features, conspecific female density and proximity to successful nesting habitats from the previous breeding season had greater influences on habitat use within home ranges. Fidelity and conspecific attraction are behavioural characteristics in some waterfowl species that may exert a greater influence than habitat features in influencing prebreeding space use and habitat selection within home ranges, particularly where quality habitat is abundant. These processes may be of critical importance to a better understanding of habitat selection in breeding birds.

  3. High Performance Home Building Guide for Habitat for Humanity Affiliates

    Energy Technology Data Exchange (ETDEWEB)

    Lindsey Marburger

    2010-10-01

    This guide covers basic principles of high performance Habitat construction, steps to achieving high performance Habitat construction, resources to help improve building practices, materials, etc., and affiliate profiles and recommendations.

  4. Colonization of subterranean habitats by spiders in Central Europe

    Directory of Open Access Journals (Sweden)

    Vlastimil Růžička

    2013-05-01

    Full Text Available Using data from the Czech Republic, we studied the distribution of spiders in soils, crevice systems, scree and caves, i.e. subterranean habitats at depths spanning from 10 cm to 100 m. In total, we found 161 species. The number of species declines with increasing habitat depth, with a major drop in species richness at the depth of 10 meters. Thirteen species exhibit morphological adaptations to life in subterranean habitats. At depths greater than 10 meters, spider assemblages are almost exclusively composed of troglomorphic species. We propose a hypothesis of evolution of troglomorphisms at spiders during Quaternary climatic cycles.

  5. Chinook salmon use of spawning patches: Relative roles of habitat quality, size, and connectivity

    Science.gov (United States)

    Isaak, D.J.; Thurow, R.F.; Rieman, B.E.; Dunham, J.B.

    2007-01-01

    Declines in many native fish populations have led to reassessments of management goals and shifted priorities from consumptive uses to species preservation. As management has shifted, relevant environmental characteristics have evolved from traditional metrics that described local habitat quality to characterizations of habitat size and connectivity. Despite the implications this shift has for how habitats may be prioritized for conservation, it has been rare to assess the relative importance of these habitat components. We used an information-theoretic approach to select the best models from sets of logistic regressions that linked habitat quality, size, and connectivity to the occurrence of chinook salmon (Oncorhynchus tshawytscha) nests. Spawning distributions were censused annually from 1995 to 2004, and data were complemented with field measurements that described habitat quality in 43 suitable spawning patches across a stream network that drained 1150 km 2 in central Idaho. Results indicated that the most plausible models were dominated by measures of habitat size and connectivity, whereas habitat quality was of minor importance. Connectivity was the strongest predictor of nest occurrence, but connectivity interacted with habitat size, which became relatively more important when populations were reduced. Comparison of observed nest distributions to null model predictions confirmed that the habitat size association was driven by a biological mechanism when populations were small, but this association may have been an area-related sampling artifact at higher abundances. The implications for habitat management are that the size and connectivity of existing habitat networks should be maintained whenever possible. In situations where habitat restoration is occurring, expansion of existing areas or creation of new habitats in key areas that increase connectivity may be beneficial. Information about habitat size and connectivity also could be used to strategically

  6. Coherence between harvest and habitat management -- Joint venture perspectives

    Science.gov (United States)

    Baxter, C.K.; Nelson, J.W.; Reinecke, K.J.; Stephens, S.E.

    2006-01-01

    Introduction: In recent months, an ad hoc group of waterfowl scientists, representing the International Association of Fish and Wildlife Agencies (IAFWA) Adaptive Harvest Management (ARM) Task Force and the North American Waterfowl Management Plan (NAWMP) Committee, have collaborated as a Joint Task Group (JTG) to assess options for unifying the population goals guiding waterfowl harvest management and habitat management. The JTG has been charged with bringing coherence to the population goals of the two programs. Characterizing the problem as one of coherence indicates value judgments exist regarding its significance or perhaps existence. For purposes of this paper, we characterize the lack of coherence as the absence of consistent population goals in the two related components of waterfowl conservation habitat and harvest management. Our purpose is to support continued dialogue on the respective goals of these programs and the possible implications of discordant goals to habitat joint ventures. Our objectives are two-fold: (1) illustrate how NAWMP habitat management goals and strategies have been interpreted and pursued in both breeding and wintering areas, and (2) provide perspectives on the linkages between regional habitat management programs and harvest management. The Lower Mississippi Valley and the Prairie Pothole joint ventures (LMVJV and PPJV, respectively) will be used as examples.

  7. Mapping anuran habitat suitability to estimate effects of grassland and wetland conservation programs

    Science.gov (United States)

    Mushet, David M.; Euliss, Ned H.; Stockwell, Craig A.

    2012-01-01

    The conversion of the Northern Great Plains of North America to a landscape favoring agricultural commodity production has negatively impacted wildlife habitats. To offset impacts, conservation programs have been implemented by the U.S. Department of Agriculture and other agencies to restore grassland and wetland habitat components. To evaluate effects of these efforts on anuran habitats, we used call survey data and environmental data in ecological niche factor analyses implemented through the program Biomapper to quantify habitat suitability for five anuran species within a 196 km2 study area. Our amphibian call surveys identified Northern Leopard Frogs (Lithobates pipiens), Wood Frogs (Lithobates sylvaticus), Boreal Chorus Frogs (Pseudacris maculata), Great Plains Toads (Anaxyrus cognatus), and Woodhouse’s Toads (Anaxyrus woodhousii) occurring within the study area. Habitat suitability maps developed for each species revealed differing patterns of suitable habitat among species. The most significant findings of our mapping effort were 1) the influence of deep-water overwintering wetlands on suitable habitat for all species encountered except the Boreal Chorus Frog; 2) the lack of overlap between areas of core habitat for both the Northern Leopard Frog and Wood Frog compared to the core habitat for both toad species; and 3) the importance of conservation programs in providing grassland components of Northern Leopard Frog and Wood Frog habitat. The differences in habitats suitable for the five species we studied in the Northern Great Plains, i.e., their ecological niches, highlight the importance of utilizing an ecosystem based approach that considers the varying needs of multiple species in the development of amphibian conservation and management plans.

  8. Factors Influencing Expanded Use of Urban Marine Habitats by Foraging Wading Birds

    Science.gov (United States)

    Urban marine habitats are often utilized by wildlife for foraging and other activities despite surrounding anthropogenic impact or disturbance. However little is known of the ecological factors that determine habitat value of these and other remnant natural habitats. We examine...

  9. The remnants of restinga habitats in the brazilian Atlantic Forest of Rio de Janeiro state, Brazil: habitat loss and risk of disappearance.

    Science.gov (United States)

    Rocha, C F D; Bergallo, H G; Van Sluys, M; Alves, M A S; Jamel, C E

    2007-05-01

    "Restingas" (herbaceous/shrubby coastal sand-dune habitats) used to cover most of Rio de Janeiro State coast, and have suffered extensive degradation over the last five centuries. Using satellite images and field work, we identified the remaining restingas in the State, recording the factors that might cause their degradation. We used two mosaics of Landsat 7 scenes (spatial resolution 15 and 30 m) to map and evaluate preliminarly the remaining areas and conservation status. Each remnant area was checked in the field, degraded areas within it were mapped and subtracted from the remnants. We identified 21 restinga remnants totalling 105,285 ha. The largest and smallest restinga remnants were Jurubatiba (25,141 ha) and Itaipu (23 ha), respectively. We identified 14 causes of degradation. The most important were vegetation removal for housing developments, establishment of exotic plant species, change of original substrate, and selective removal of species of economic importance for the horticultural industry. All restingas had disturbed parts under strong pressure due to human activities. Due to intense habitat loss, and occurrence of endemic/threatened vertebrate species in restinga habitats, we strongly indicate the implementation of new conservation units to protect these fragile remnants. This habitat is steadily decreasing and most remnants lack legal protection. Therefore, under the current human pressure most of this unique habitat is likely to be lost from the State within the next few years.

  10. Home range characteristics of Mexican Spotted Owls in the Rincon Mountains, Arizona

    Science.gov (United States)

    Willey, David W.; van Riper, Charles

    2014-01-01

    We studied a small isolated population of Mexican Spotted Owls (Strix occidentalis lucida) from 1996–1997 in the Rincon Mountains of Saguaro National Park, southeastern Arizona, USA. All mixed-conifer and pine-oak forest patches in the park were surveyed for Spotted Owls, and we located, captured, and radio-tagged 10 adult birds representing five mated pairs. Using radio-telemetry, we examined owl home range characteristics, roost habitat, and monitored reproduction within these five territories. Breeding season (Mar–Sep) home range size for 10 adult owls (95% adaptive kernel isopleths) averaged 267 ha (±207 SD), and varied widely among owls (range 34–652 ha). Mean home range size for owl pairs was 478 ha (±417 ha SD), and ranged from 70–1,160 ha. Owls that produced young used smaller home ranges than owls that had no young. Six habitat variables differed significantly between roost and random sites, including: percent canopy cover, number of trees, number of vegetation layers, average height of trees, average diameter of trees, and tree basal area. Radio-marked owls remained in their territories following small prescribed management fires within those territories, exhibiting no proximate effects to the presence of prescribed fire.

  11. ADVANCING TORPOR INDUCING TRANSFER HABITATS FOR HUMAN STASIS TO MARS

    Data.gov (United States)

    National Aeronautics and Space Administration — SpaceWorks proposes the development of an advanced habitat system for transporting crews between the Earth and Mars. This new and innovative habitat design is...

  12. Riparian Habitat - San Joaquin River

    Data.gov (United States)

    California Natural Resource Agency — The immediate focus of this study is to identify, describe and map the extent and diversity of riparian habitats found along the main stem of the San Joaquin River,...

  13. Mapping and modelling the habitat of giant pandas in Foping Nature Reserve, China

    NARCIS (Netherlands)

    Liu, X.

    2001-01-01

    The fact that only about 1000 giant pandas and 29500 km2 of panda habitat are left in the west part of China makes it an urgent issue to save this endangered animal species and protect its habitat. For effective conservation of the giant panda and its habitat, a thorough evaluation of panda habitat

  14. Evaluation of nekton use and habitat characteristics of restored Louisiana marsh

    Science.gov (United States)

    Thom, C.S.B.; Peyre, M.K.G.L.; Nyman, J.A.

    2004-01-01

    Marsh terracing and coconut fiber mats are two wetland restoration techniques implemented at Sabine National Wildlife Refuge, Louisiana, USA. Using nekton as an indicator of habitat quality, nekton community assemblages were compared between terraced, coconut-matted, unmanaged marsh (restoration goal), and open water (pre-restoration) habitats. Using a throw trap and a 3 m ?? 2 m straight seine, 192 nekton samples were collected over four dates in 2001 and 2002 at all habitats. Nekton abundance was similar at unmanaged marsh (restoration goal), coconut mat, and terrace edge, and significantly higher than at open water (pre-restoration) sites (P Coconut-matted habitat and unmanaged marsh edges had significantly higher numbers of benthic dependent species than terrace edges (P coconut-matted sites. Future restoration projects may evaluate the combined use of coconut mats with terracing projects in order to enhance habitat for benthic dependent nekton.

  15. Urban Marine Habitat Use by Waterbirds in Narragansett Bay

    Science.gov (United States)

    We examined patterns of habitat use by waterbirds (waterfowl, shorebirds, and wading birds) at a series of urban and non-urban marine habitats in Narragansett Bay during 2005-2007. Average waterbird abundance at urban sites was significantly higher than at rural sites (304 ± 59.7...

  16. Essential coastal habitats for fish in the Baltic Sea

    DEFF Research Database (Denmark)

    Kraufvelin, Patrik; Pekcan-Hekim, Zeynep; Bergström, Ulf

    2018-01-01

    Many coastal and offshore fish species are highly dependent on specific habitat types for population maintenance. In the Baltic Sea, shallow productive habitats in the coastal zone such as wetlands, vegetated flads/lagoons and sheltered bays as well as more exposed rocky and sandy areas are utili...

  17. Habitat structure mediates biodiversity effects on ecosystem properties.

    Science.gov (United States)

    Godbold, J A; Bulling, M T; Solan, M

    2011-08-22

    Much of what we know about the role of biodiversity in mediating ecosystem processes and function stems from manipulative experiments, which have largely been performed in isolated, homogeneous environments that do not incorporate habitat structure or allow natural community dynamics to develop. Here, we use a range of habitat configurations in a model marine benthic system to investigate the effects of species composition, resource heterogeneity and patch connectivity on ecosystem properties at both the patch (bioturbation intensity) and multi-patch (nutrient concentration) scale. We show that allowing fauna to move and preferentially select patches alters local species composition and density distributions, which has negative effects on ecosystem processes (bioturbation intensity) at the patch scale, but overall positive effects on ecosystem functioning (nutrient concentration) at the multi-patch scale. Our findings provide important evidence that community dynamics alter in response to localized resource heterogeneity and that these small-scale variations in habitat structure influence species contributions to ecosystem properties at larger scales. We conclude that habitat complexity forms an important buffer against disturbance and that contemporary estimates of the level of biodiversity required for maintaining future multi-functional systems may need to be revised.

  18. Subsurface microbial habitats on Mars

    Science.gov (United States)

    Boston, P. J.; Mckay, C. P.

    1991-01-01

    We developed scenarios for shallow and deep subsurface cryptic niches for microbial life on Mars. Such habitats could have considerably prolonged the persistence of life on Mars as surface conditions became increasingly inhospitable. The scenarios rely on geothermal hot spots existing below the near or deep subsurface of Mars. Recent advances in the comparatively new field of deep subsurface microbiology have revealed previously unsuspected rich aerobic and anaerobic microbal communities far below the surface of the Earth. Such habitats, protected from the grim surface conditions on Mars, could receive warmth from below and maintain water in its liquid state. In addition, geothermally or volcanically reduced gases percolating from below through a microbiologically active zone could provide the reducing power needed for a closed or semi-closed microbial ecosystem to thrive.

  19. Predicting 21st-century polar bear habitat distribution from global climate models

    Science.gov (United States)

    Durner, George M.; Douglas, David C.; Nielson, R.M.; Amstrup, Steven C.; McDonald, T.L.; Stirling, I.; Mauritzen, Mette; Born, E.W.; Wiig, O.; Deweaver, E.; Serreze, Mark C.; Belikov, Stanislav; Holland, M.M.; Maslanik, J.; Aars, Jon; Bailey, D.A.; Derocher, A.E.

    2009-01-01

    Projections of polar bear (Ursus maritimus) sea ice habitat distribution in the polar basin during the 21st century were developed to understand the consequences of anticipated sea ice reductions on polar bear populations. We used location data from satellitecollared polar bears and environmental data (e.g., bathymetry, distance to coastlines, and sea ice) collected from 1985 to 1995 to build resource selection functions (RSFs). RSFs described habitats that polar bears preferred in summer, autumn, winter, and spring. When applied to independent data from 1996 to 2006, the RSFs consistently identified habitats most frequently used by polar bears. We applied the RSFs to monthly maps of 21st-century sea ice concentration projected by 10 general circulation models (GCMs) used in the Intergovernmental Panel of Climate Change Fourth Assessment Report, under the A1B greenhouse gas forcing scenario. Despite variation in their projections, all GCMs indicated habitat losses in the polar basin during the 21st century. Losses in the highest-valued RSF habitat (optimal habitat) were greatest in the southern seas of the polar basin, especially the Chukchi and Barents seas, and least along the Arctic Ocean shores of Banks Island to northern Greenland. Mean loss of optimal polar bear habitat was greatest during summer; from an observed 1.0 million km2 in 1985-1995 (baseline) to a projected multi-model mean of 0.32 million km2 in 2090-2099 (-68% change). Projected winter losses of polar bear habitat were less: from 1.7 million km2 in 1985-1995 to 1.4 million km2 in 2090-2099 (-17% change). Habitat losses based on GCM multi-model means may be conservative; simulated rates of habitat loss during 1985-2006 from many GCMs were less than the actual observed rates of loss. Although a reduction in the total amount of optimal habitat will likely reduce polar bear populations, exact relationships between habitat losses and population demographics remain unknown. Density and energetic

  20. Northeast Puerto Rico and Culebra Island - Benthic Habitat Map 2015

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This benthic habitat map was created from a semi-automated habitat mapping process, using a combination of bathymetry, satellite imagery, aerial imagery and...