Journal articles on the topic 'Winter habitat'
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1
Poole, Kim G., and Kari Stuart-Smith. "Winter habitat selection by female moose in western interior montane forests." Canadian Journal of Zoology 84, no. 12 (December 2006): 1823–32. http://dx.doi.org/10.1139/z06-184.
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Winter range has been identified as an important component of moose ( Alces alces (L., 1758)) conservation in managed forests, yet there have been few studies on habitat associations in montane ecosystems. We investigated habitat selection by moose at landscape and stand scales during late winter in southeastern British Columbia using global positioning system (GPS) collars on 24 adult moose cows in each of two winters. The strongest determinant of late-winter range at the landscape scale was decreasing elevation, while moose also selected for areas of gentler slopes and higher solar insolation. Elevation likely is a surrogate for snow depth, which is probably the primary causative factor influencing late-winter distribution of moose. Within late-winter range, topographic variables had little influence on moose habitat selection. Lower crown closure was the strongest determinant of stand-scale selection, although the resultant model was weak. We found no disproportionate selection for stands with high crown closure, and there was little evidence for greater use of cover stands with increasing snow as winter progressed. Within late-winter range, moose selected forage habitats (42% use vs. 30% availability) over cover habitats (22% use vs. 37% availability). The delineation of late-winter moose range can be based on snow depth, or elevation as its surrogate.
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Nickelson, Thomas E., Mario F. Solazzi, Steven L. Johnson, and Jeffrey D. Rodgers. "Effectiveness of Selected Stream Improvement Techniques to Create Suitable Summer and Winter Rearing Habitat for Juvenile Coho Salmon (Oncorhynchus kisutch) in Oregon Coastal Streams." Canadian Journal of Fisheries and Aquatic Sciences 49, no. 4 (April 1, 1992): 790–94. http://dx.doi.org/10.1139/f92-089.
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We examined the use of constructed pools by juvenile coho salmon (Oncorhynchus kisutch) during summer and winter. Log, gabion, and rock structures placed across the full stream width provided good summer habitat but poor winter habitat for juvenile coho salmon. Rearing densities in constructed habitats during summer and winter were generally similar to those in natural habitats of the same type, except that constructed dammed pools supported lower densities during winter than natural dammed pools. The addition of brush bundles to pools created by full-stream-width structures increased the density of juvenile coho salmon in dammed pools during winter, but not in plunge pools. We concluded that the development of off-channel habitat has the greatest potential to increase production of wild coho salmon smolts in Oregon coastal streams.
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Alfredsen, Knut, and Einar Tesaker. "Winter habitat assessment strategies and incorporation of winter habitat in the Norwegian habitat assessment tools." Hydrological Processes 16, no. 4 (2002): 927–36. http://dx.doi.org/10.1002/hyp.364.
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FARASHI, AZITA, and MOHAMMAD ALIZADEH-NOUGHANI. "Niche modelling of the potential distribution of the Egyptian Vulture Neophron percnopterus during summer and winter in Iran, to identify gaps in protected area coverage." Bird Conservation International 29, no. 03 (November 29, 2018): 423–36. http://dx.doi.org/10.1017/s0959270918000278.
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SummaryAn analysis of the extent of overlap between habitats of the Egyptian Vulture Neophron percnopterus during summer and winter in Iran, and Iranian protected areas, discovered slight overlap between the two. Our study aimed to survey suitable habitats of the Egyptian Vulture during summer and winter in Iran using MaxEnt, a species distribution modelling method, and compare the results with the locations and span of protected areas. Model fitness was assessed using the area under the ROC-plot and True Skill Statistics. We found that habitat suitability in Iran varies for the Egyptian Vulture during summer and winter. Summer visitors are scattered in the north and west of Iran, concentrated along the Zagros and Alborz mountain ranges. Winter visitors and residents are scattered in coastal areas in the south. Habitat protection for winter visitors was the greatest, with 10% of suitable habitat covered, while less than 10% of suitable habitat for residents and summer visitors fell within protected areas. The Egyptian Vulture is categorised as ‘Endangered’ on the IUCN Red List. Different environmental factors influence the suitability of habitat for the species. While some factors such as NDVI and anthropogenic disturbance influence all visitors in a similar way, the effects of others such as elevation and distance from protected areas vary for summer and winter visitors. Since designation of protected areas in Iran is mainly determined by the distribution of mammal species, protection of bird habitats is often overlooked. Suitable habitat for the species should be considered when selecting protected areas in future.
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Proulx, Gilbert. "Winter Habitat Use by American Marten, Martes americana, in Western Alberta Boreal Forests." Canadian Field-Naturalist 120, no. 1 (January 1, 2006): 100. http://dx.doi.org/10.22621/cfn.v120i1.253.
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Although the American Marten (Martes americana) is found in most forest regions of Alberta, little is known about its choice of winter habitats. This study investigated winter habitat use by American Marten in Weyerhaeuser’s Grande Prairie Forest Management Area (FMA) using snowtracking along 128.2 km of seismic lines inventoried in winters 1999, 2002, and 2005 with snowmobiles. American Marten tracks (n = 44) occurred significantly less frequently than expected (P < 0.001) in immature/young pole stands, but more frequently than expected (P < 0.02) in mature/old growth mixedwood stands. American Martens apparently used young forests, and mature/old coniferous and deciduous stands, according to their availability. Forest development plans should be developed locally to retain late successional forests that meet the winter habitat requirements of American Marten.
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Sabine, Dwayne L., Graham Forbes, Warren B. Ballard, Jeff Bowman, and Heather Whitlaw. "Use of mixedwood stands by wintering white-tailed deer in southern New Brunswick." Forestry Chronicle 77, no. 1 (February 1, 2001): 97–103. http://dx.doi.org/10.5558/tfc77097-1.
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On the northern edge of their range, white-tailed deer (Odocoileus virginianus) congregate during winter to cope with severe climate conditions. We documented the winter habitat use of deer in southern New Brunswick, where winters are of moderate severity, and tested predictions concerning the influence of food and cover availability on habitat use by deer under different snow depth regimes. Sixty-three radio-collared deer were monitored during the winters of 1995 to 1997. Within wintering areas, deer showed a preference for mixedwoods. Mixedwood stands provided only moderate amounts of food and cover relative to some other cover types, but were the only type to provide both simultaneously. Current habitat management guidelines in parts of northeastern North America consider critical habitat for wintering deer to be softwood-dominated stands. These guidelines may not provide adequate habitat in this region, since deer appear to use mixedwood stands under some conditions. Key words: deer, deer wintering area, deer yard, habitat, habitat management, mixedwood, Odocoileus, winter, yard
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Whalen, Kevin G., and Donna L. Parrish. "Nocturnal habitat use of Atlantic salmon parr in winter." Canadian Journal of Fisheries and Aquatic Sciences 56, no. 9 (September 1, 1999): 1543–50. http://dx.doi.org/10.1139/f99-078.
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We completed 22 night snorkeling surveys between November and March 1995-1997 to quantify Atlantic salmon (Salmo salar) parr habitat use relative to habitat availability in the Rock River, Vermont, U.S.A. On average, post-young-of-the-year (PYOY) parr selected greater water depths in winter than young-of-the-year (YOY) parr, whereas YOY and PYOY parr both selected water velocities ([Formula: see text]19 cm/s) that were significantly lower than random measurements (46 cm/s). Maturity of PYOY parr had no significant influence on habitat selection. The majority of YOY and PYOY parr at night were found in contact with the stream bottom resting on silt-sand or gravel substrates in velocity dead-zone habitats created by the stream edge or depositional habitats created by midstream rocks and boulders. The strong selection that nocturnal Atlantic salmon parr exhibit for low water velocity areas in winter indicates the importance of maintaining large instream cover that provides refuges from high flows. The similarity that YOY and PYOY parr exhibited in many elements of habitat selection suggests that both stages may be similarly susceptible to habitat limitations in winter.
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Hjeljord, Olav, Bernt-Erik Sæther, and Reidar Andersen. "Estimating energy intake of free-ranging moose cows and calves through collection of feces." Canadian Journal of Zoology 72, no. 8 (August 1, 1994): 1409–15. http://dx.doi.org/10.1139/z94-186.
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We calculated the daily energy intake of wintering cow and calf moose from a series of 24-h feces collections and from estimates of the digestibility and energy content of forages from four different habitats in Norway during a 3-year period (1984–1986). Habitats varied in condition from good to poor. In early winter, the estimated energy intake of cows ranged from 803 kJ∙kg−0.75∙day−1 in the good- and average-quality habitats to 573 kJ∙kg−0.75∙day−1 in the poor habitat. Estimated energy intake decreased by 15–30% from early to late winter. The estimated energy intake of calves ranged from 920 kJ∙kg−0.75∙day−1 in the good habitat to 414 kJ∙kg−0.75∙day−1 in the poor habitat; a significant decrease over winter was not evident. The estimates of daily energy intake correspond to a browse wet mass of 8–17 kg for cows and 4–10 kg for calves. In the good- and medium-quality habitats the average energy deficiency of adult cows over winter was estimated at 25–30%.
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Whalen, Kevin G., Donna L. Parrish, and Martha E. Mather. "Effect of ice formation on selection of habitats and winter distribution of post-young-of-the-year Atlantic salmon parr." Canadian Journal of Fisheries and Aquatic Sciences 56, no. 1 (January 1, 1999): 87–96. http://dx.doi.org/10.1139/f98-156.
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We determined how ice affects selection of habitats and distribution of post-young-of-the-year Atlantic salmon (Salmo salar) parr during winter. Night snorkeling surveys were completed between November and April to evaluate parr habitat use and movements. Systematic measurements of water depth and velocity were recorded during ice-free and [Formula: see text]55% iced conditions to quantify habitat availability. Ice formation altered the distribution and reduced the abundance of habitats commonly used by parr; differences between parr habitat use and habitat availability were greatest when ice was present. Edge ice formation resulted in the concentration of flows, and areas of high flow were formed in midchannel; few parr were observed in midchannel after ice had formed. Through the winter, most parr were found lateral to high flows on the ice edge boundary or in the post-ice period lateral to the stream midchannel. The correspondence of parr movements during winter to changes in the physical habitat associated with ice formation indicates that movements and redistributions may be important for survival in streams affected by ice.
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Poole, Kim G., Kari Stuart-Smith, and Irene E. Teske. "Wintering strategies by mountain goats in interior mountains." Canadian Journal of Zoology 87, no. 3 (March 2009): 273–83. http://dx.doi.org/10.1139/z09-009.
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As with many ungulates inhabiting areas with potentially deep snow, winter is an important season for mountain goats ( Oreamnos americanus (de Blainville, 1816)) and is characterized by restricted movements and high juvenile mortality. We examined winter habitat selection and wintering strategies by mountain goats in two adjacent areas of southeastern British Columbia characterized by deep, moist snow and by shallow, dry snow. Fifteen GPS collars were placed on mountain goats in each area over two winters. Winter-range size did not differ between areas and comprised, on average, 2.2%–7.4% of male home range and 8.0%–14.1% of female home range. Topographic variables dominated habitat model selection. At the broad scale, mountain goats in both areas selected winter ranges closer to escape terrain on warmer aspects that contained lesser amounts of mature dense forest. At the fine scale, mountain goats in both areas selected rugged habitat at upper mid-elevations and on warmer aspects. Alpine areas were avoided in the deep snow area and selected in the shallow snow area. No selection for mature forests was observed in either area. Mountain goats, therefore, appeared to utilize open, high-elevation habitats in shallow snow zones, but they did not seek reduced snow levels in mature forest stands in deep snow areas.
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Halpin, Margaret A., and John A. Bissonette. "Influence of snow depth on prey availability and habitat use by red fox." Canadian Journal of Zoology 66, no. 3 (March 1, 1988): 587–92. http://dx.doi.org/10.1139/z88-086.
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Habitat use by red fox (Vulpes vulpes) was studied during the winters of 1982 and 1983. A total of 125 km of fox trails in eastern Maine were followed during periods of snow cover to examine the influence of snow conditions on fox habitat selection and prey availability. Red foxes used all available habitats but showed preferences for softwood stands and open areas. Hardwood forests were avoided. During both winters, snow depth was greatest in hardwood and mixed stands where soft, powdery conditions prevailed. Windblown, supportive crusts were found in open barrens. Foxes showed habitat preferences for traveling and hunting. Fox sinking depths were least in all habitats when crust conditions prevailed, and during these periods travel distances were more evenly distributed among habitats. Snow influenced relative prey availability. Hunting activities shifted among habitats for small mammals during most of the second winter, when snow was shallow. Proportions of small mammals in the fox diet decreased as snow accumulated and as crusts formed. When snow was deep, foxes hunted in habitats with softwood regeneration and other dense understories that supported snowshoe hare concentrations.
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Mäki-Petäys, Aki, Jaakko Erkinaro, Eero Niemelä, Ari Huusko, and Timo Muotka. "Spatial distribution of juvenile Atlantic salmon (Salmo salar) in a subarctic river: size-specific changes in a strongly seasonal environment." Canadian Journal of Fisheries and Aquatic Sciences 61, no. 12 (December 1, 2004): 2329–38. http://dx.doi.org/10.1139/f04-218.
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We examined seasonal variation in the spatial distribution and habitat preference of juvenile Atlantic salmon (Salmo salar) in a subarctic river characterized by near-zero water temperatures for 78 months a year. Size-specific differences in habitat use were pronounced in summer but disappeared at the onset of winter, when the habitats preferred by small (≤6 cm) and larger (717 cm) salmon overlapped heavily. Small salmon favoured low-velocity habitats during all seasons, and in summer and autumn they mainly occupied shallow microhabitats along stream margins. In winter and spring, small salmon preferred deeper habitats farther away from the shoreline. Larger salmon favoured deeper habitats in all seasons, but they only occupied slowly flowing areas at low water temperatures. Since all salmon size classes were closely associated with deep and low-velocity habitats in winter and spring, this time of year may represent a size-selective bottleneck for Atlantic salmon populations. Therefore, management schemes aiming to enhance salmonid habitats in boreal streams must rest on the knowledge of season- and size-specific habitat requirements of salmonid species.
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Larter, Nicholas C., and Cormack C. Gates. "Diet and habitat selection of wood bison in relation to seasonal changes in forage quantity and quality." Canadian Journal of Zoology 69, no. 10 (October 1, 1991): 2677–85. http://dx.doi.org/10.1139/z91-376.
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Diet and habitat selection of wood bison (Bison bison athabascae) were studied in the Mackenzie Bison Sanctuary, Northwest Territories, between February 1986 and April 1988. Wood bison showed pronounced seasonal changes in diet. Sedges constituted 96.1–98.8% of the winter diet. During summer, the diet became a more diverse mix of sedge (Carex spp.), grass (Graminae), and willow (Salix spp.). Lichen (Cladina mitis) became a major dietary component in fall. Summer browsing on willows increased when sedge standing crops were reduced. Forage availability was the main factor determining habitat selection. Wet sedge meadows provided the most available crude protein in winter and were the preferred winter habitat. Willow savannas provided the most available crude protein in summer and were the preferred summer habitat. Between June and October, all forages except lichen decreased in nitrogen content and increased in fibre content. The lack of distinct habitat preference in fall corresponded to dispersion of animals into forested habitats, increased use of lichen as forage, and more homogeneous availability of crude protein among habitats. Snow conditions were harsher in 1987–1988 than in 1986–1987, which affected forage availability and caused a noticeable shift in habitat use.
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Jakimchuk, R. D., S. H. Ferguson, and L. G. Sopuck. "Differential habitat use and sexual segregation in the Central Arctic caribou herd." Canadian Journal of Zoology 65, no. 3 (March 1, 1987): 534–41. http://dx.doi.org/10.1139/z87-083.
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Distribution of the Central Arctic caribou herd is characterized by segregation of the sexes and different habitat preferences by male and female caribou over most of the annual cycle. During all periods except late winter and postcalving, females showed a more northern distribution than did males. Females used riparian habitats less than availability and were generally farther from major river valleys than expected during all seasons except late winter. In contrast, males preferred riparian habitats from late winter to calving and were generally found closer to river valleys than were females from late winter to August dispersal. During the spring and calving periods near the coast females preferred sedge meadow and used riparian habitat less than availability whereas males preferred riparian and tussock tundra and used sedge meadow less than availability. It is theorized that sexual segregation and differential habitat use reflect predator avoidance strategies of females with calves and optimal foraging by adult males.
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Timmermann, H. R., and J. G. McNicol. "Moose Habitat Needs." Forestry Chronicle 64, no. 3 (June 1, 1988): 238–45. http://dx.doi.org/10.5558/tfc64238-3.
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A review of the literature describing moose habitat needs is presented. The growing season is a period of positive energy balance when moose feed extensively on a variety of deciduous leaves, aquatic macrophytes and herbaceous vegetation which satisfy nutritional requirements for weight gain and development. In winter, a period of negative energy balance, food intake and metabolism are reduced to conserve energy and minimize weight loss. In addition, good moose winter habitat includes shelter from extreme temperatures, deep snow and access to secure areas to help avoid predators expecially during spring calving. Optimum habitats contain an interspersion of food and cover within traditionally used seasonal home ranges.
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Marra, Peter P., and Richard T. Holmes. "Consequences of Dominance-Mediated Habitat Segregation in American Redstarts During the Nonbreeding Season." Auk 118, no. 1 (January 1, 2001): 92–104. http://dx.doi.org/10.1093/auk/118.1.92.
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Abstract Several species of migratory songbirds exhibit a distinct form of habitat segregation while on their Neotropical wintering grounds in which males and females occupy different habitat types. In the American Redstart (Setophaga ruticilla), that sexual habitat segregation is a result of behavioral dominance of older males. In that study, we examined whether such dominance behavior and the resulting differential habitat segregation has consequences for the condition or survival of excluded individuals. We quantified the physical condition and survival of redstarts (both males and females) occupying two habitat types that differed in the proportion of males and females present in Jamaica. Both sexes of redstarts occupying female-biased habitat lost significantly more mass over-winter and had lower annual survival and longevity compared to individuals in male-biased habitat. These results suggest that nonbreeding habitats differed in suitability, with the least suitable habitat being occupied predominately by females. Because most female redstarts are forced to over-winter in these kinds of habitats, they may often be in poor physiological condition prior to departing on spring migration for the breeding grounds. This in turn may influence dynamics of the breeding period by determining their condition and perhaps reproductive success. Furthermore, because winter habitat segregation appears to lower female survivorship, it may also limit the number and availability of breeding females. These results implicate events that occur during the nonbreeding period as playing a critical role in the annual dynamics of this migratory species.
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Mason, Christopher F., and Sheila M. Macdonald. "Winter bird numbers and land-use preferences in an arable landscape in eastern England." Bird Conservation International 9, no. 2 (June 1999): 119–27. http://dx.doi.org/10.1017/s0959270900002240.
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SummaryThe winter bird assemblage and habitat preferences were studied in a largely arable landscape, dominated by winter cereals, in eastern England in one winter. A total of species was recorded on 70 l-km transects but 11% of transects had no birds. Overall densities were low, Skylark Alauda arvensis being the most abundant species. Bird was highest in the first winter period (October-December). Species richness varied proportion to the available habitat in the first winter period but there was a preference for stubble, grass and tilled land (harrow) in the second winter period (January-February) Skylarks preferred stubbles in the first winter period and stubbles and grass in the second winter period. Some 34% of all birds fed on winter cereals despite a lack of preference for this habitat, while 94% of seed specialists (finches and buntings) were recorded on stubbles. The areas of preferred habitats (stubbles, grass) were probably too limited to allow more than small populations to persist. Only by the widespread adoption of agricultural extensification and/or farming some of the land specifically for conservation benefits can the declines in bird populations on intensively managed arable farmland be reversed.
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Ingle, Kapilkumar, Hardeep Kaur, Nikolett Gallé-Szpisjak, József Bürgés, Áron Szabó, and Róbert Gallé. "Winter-Active Spider Fauna is Affected by Plantation Forest Type." Environmental Entomology 49, no. 3 (March 11, 2020): 601–6. http://dx.doi.org/10.1093/ee/nvaa025.
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Abstract Plantations of non-native trees for commercial use are common practice in Europe. They are known to have severe ecological impacts on arthropod fauna by altering microclimatic conditions and reducing microhabitat diversity. However, the effect of plantation tree species on winter-active fauna is relatively unknown. Spiders are a diverse predatory arthropod taxon with strong effect on their prey populations. The composition of spider communities sensitively indicates changes in habitat structure. We established 40 sampling sites in five non-native pine and five native poplar plantations and collected spiders with pitfall traps for two winters in the Southern part of Hungary. We assessed the average height of vegetation and percentage cover of leaf litter, mosses, herbaceous vegetation, and shrubs to characterize habitat structure. We found species richness and activity density of spiders in the non-native compared to the native plantations, presumably due to the more temperate microclimate in pine than in poplar plantations. However, there was no significant effect of habitat structure and its interaction with forest type on species richness and activity density of spiders. Species composition of non-native and native plantation forests differed significantly. Furthermore, we identified six characteristic spider species of non-native plantations with preference for relatively moist habitat conditions. The single characteristic species, (Agroeca cuprea Menge, 1873) for the native plantations preferred dry and partly shaded habitats. We conclude that the effect of microclimatic differences and prey availability presumably overrides the effect of habitat structure on winter-active spiders.
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Koronkiewicz, Thomas J., Mark K. Sogge, Charles Van Riper, and Eben H. Paxton. "Territoriality, Site Fidelity, and Survivorship of Willow Flycatchers Wintering in Costa Rica." Condor 108, no. 3 (August 1, 2006): 558–70. http://dx.doi.org/10.1093/condor/108.3.558.
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AbstractWe studied wintering Willow Flycatchers (Empidonax traillii) in two seasonal freshwater wetland habitats in northwestern Costa Rica during five boreal winters, to determine habitat occupancy, overwinter and between-year site and territory fidelity, and the degree to which the sexes maintain and defend winter territories. Both males and females used agonistic displays, song, and other vocalizations to maintain and defend mutually exclusive winter territories. Males were generally more abundant than females, but this varied by site and year. There was no significant difference in male and female territory size, nor any indication of sexual habitat segregation. Similarity in morphology and aggressiveness between the sexes may account for the lack of habitat segregation and the ability of females to maintain territories at wintering sites. Each year, 80%–92% of banded flycatchers that were present in midwinter remained at the site until late winter; of these, 86%–100% of individuals maintained the same territories throughout the entire period. We also observed nonterritorial floaters that subsequently established and held winter territories. Between-year site fidelity averaged 68%, and almost all returning birds established territories with boundaries similar to the previous year. Between-year apparent survivorship estimates ranged annually from 54%–72%, with no difference between sites but weak support for higher survivorship of males compared to females. Values for winter site and territory fidelity were generally higher than those reported for other species and for Willow Flycatchers on the breeding grounds; between-year survivorship estimates were similar to those reported for breeding flycatchers.
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Esler, Daniel, Timothy D. Bowman, Thomas A. Dean, Charles E. O'Clair, Stephen C. Jewett, and Lyman L. McDonald. "Correlates of Harlequin Duck Densities During Winter In Prince William Sound, Alaska." Condor 102, no. 4 (November 1, 2000): 920–26. http://dx.doi.org/10.1093/condor/102.4.920.
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Abstract We evaluated relationships of Harlequin Duck (Histrionicus histrionicus) densities to habitat attributes, history of habitat contamination by the 1989 Exxon Valdez oil spill, and prey biomass density and abundance during winters 1995–1997 in Prince William Sound, Alaska. Habitat features that explained variation in duck densities included distance to streams and reefs, degree of exposure to wind and wave action, and dominant substrate type. After accounting for these effects, densities were lower in oiled than unoiled areas, suggesting that population recovery from the oil spill was not complete, due either to lack of recovery from initial oil spill effects or continuing deleterious effects. Prey biomass density and abundance were not strongly related to duck densities after accounting for habitat and area effects. Traits of Harlequin Ducks that reflect their affiliation with naturally predictable winter habitats, such as strong site fidelity and intolerance of increased energy costs, may make their populations particularly vulnerable to chronic oil spill effects and slow to recover from population reductions, which may explain lower densities than expected on oiled areas nearly a decade following the oil spill.
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Danks, H. V. "How aquatic insects live in cold climates." Canadian Entomologist 139, no. 4 (August 2007): 443–71. http://dx.doi.org/10.4039/n06-100.
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AbstractIn cold climates most aquatic habitats are frozen for many months. Nevertheless, even in such regions the conditions in different types of habitat, in different parts of one habitat, and from one year to the next can vary considerably; some water bodies even allow winter growth. Winter cold and ice provide challenges for aquatic insects, but so do high spring flows, short, cool summers, and unpredictable conditions. General adaptations to cope with these constraints, depending on species and habitat, include the use of widely available foods, increased food range, prolonged development (including development lasting more than one year per generation), programmed life cycles with diapause and other responses to environmental cues (often enforcing strict univoltinism), and staggered development. Winter conditions may be anticipated not only by diapause and related responses but also by movement for the winter to terrestrial habitats, to less severe aquatic habitats, or to different parts of the same habitat, and by construction of shelters. Winter itself is met by various types of cold hardiness, including tolerance of freezing in at least some species, especially chironomid midges, and supercooling even when surrounded by ice in others. Special cocoons provide protection in some species. A few species move during winter or resist anoxia beneath ice. Spring challenges of high flows and ice scour may be withstood or avoided by wintering in less severe habitats, penetrating the substrate, or delaying activity until after peak flow. However, where possible species emerge early in the spring to compensate for the shortness of the summer season, a trait enhanced (at least in some lentic habitats) by choosing overwintering sites that warm up first in spring. Relatively low summer temperatures are offset by development at low temperatures, by selection of warm habitats and microhabitats, and in adults by thermoregulation and modified mating activity. Notwithstanding the many abiotic constraints in cold climates, aquatic communities are relatively diverse, though dominated by taxa that combine traits such as cold adaptation with use of the habitats and foods that are most widely available and most favourable. Consequently, except in the most severe habitats, food chains and community structure are complex even at high latitudes and elevations, including many links between aquatic and terrestrial habitats. Despite the complex involvement of aquatic insects in these cold-climate ecosystems, we know relatively little about the physiological and biochemical basis of their cold hardiness and its relationship to habitat conditions, especially compared with information about terrestrial species from the same regions.
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Woodward, Jennifer, Jenny Sika, Carl Wambolt, Jay Newell, Sean Schroff, and Bok Sowell. "Sage-Grouse Nesting, Brood and Winter Habitat Characteristics in Montana." Environmental Management and Sustainable Development 5, no. 1 (February 18, 2016): 126. http://dx.doi.org/10.5296/emsd.v5i1.9048.
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<p class="emsd"><span lang="EN-GB">Greater sage-grouse (Centrocercus urophasianus) habitat characteristics were studied in central Montana primarily on Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis Beetle & Young) dominated rangeland. The primary objective was to compare shrub and herbaceous parameters within (use, random or non-use) and between seasonal habitats (nest, brood, winter). Two study sites (Musselshell and Golden Valley counties), and 2 years (2004 and 2005) were compared. Nest, brood, and random sites were compared for herbaceous cover, and grass height (n = 648). Nest, brood, random, winter use and winter non-use sites were evaluated for shrub cover, density, and height. All differences were considered significant at P ≤ 0.05. Sage-grouse nested in areas with greater total shrub cover and height, and taller live and residual grass than was randomly available. No differences were found between brood and paired random sites for any of the herbaceous or shrub parameters measured. Shrub cover and density were greater at winter use sites than non-use sites. Winter use sites had less shrub cover than nest sites. The nest and brood habitat had similar shrub cover, density, and height on the study area. Sage-grouse habitats should be managed to include sagebrush, forbs, and grass. Herbaceous vegetation was more important during nesting and brood rearing than during the winter. Therefore, some portions of <span>sage-</span>grouse habitat may benefit from management for greater herbaceous cover, but not at the expense of removing sagebrush. Sagebrush cover from 10 to 15 percent was the most consistent component of sage-grouse habitat.</span></p>
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Andersen, Brett R., Liam P. McGuire, Thomas Bently Wigley, Darren A. Miller, and Richard D. Stevens. "Habitat Associations of Overwintering Bats in Managed Pine Forest Landscapes." Forests 13, no. 5 (May 20, 2022): 803. http://dx.doi.org/10.3390/f13050803.
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Research Highlights: Seasonal variation in environmental conditions coinciding with reproductive and energetic demands might result in seasonal differences in species-specific habitat use. We studied a winter assemblage of insectivorous bats and found that species acted as habitat generalists during winter compared to expectations based on the summer active season. Background and Objectives: In temperate regions, seasonal fluctuations in resource availability might restructure local bat assemblages. Initially perceived to only hibernate or migrate to avoid adverse winter conditions, temperate insectivorous bats appear to also employ intermediate overwintering strategies, as a growing body of literature suggests that winter activity is quite prevalent and even common in some lower latitude areas. However, to date, most studies have exclusively assessed habitat associations during summer. Because habitat use during summer is strongly influenced by reproduction, we hypothesized that habitat associations might differ during the non-reproductive winter period. We used acoustic monitoring to assess the habitat associations of bats across a managed pine landscape in the southeastern United States. Materials and Methods: During the winters of 2018 and 2019, we deployed acoustic detectors at 72 unique locations to monitor bat activity and characterized vegetation conditions at two scales (microhabitat and landscape). We used linear mixed models to characterize species-specific activity patterns associated with different vegetation conditions. Results: We found little evidence of different activity patterns during winter. The activity of three species (hoary bat: Lasiurus cinereus; southeastern myotis: Myotis austroriparius; and tricolored bat: Perimyotis subflavus) was not related to vegetation variables and only modest relationships were evident for four other species/groups (big brown bat: Eptesicus fuscus; eastern red bat: L. borealis; Seminole bat: L. seminolus; evening bat: Nycticeius humeralis; and Brazilian free-tailed bat: Tadarida brasiliensis). Conclusions: During winter, the bats in our study were active across the landscape in various cover types, suggesting that they do not exhibit the same habitat associations as in summer. Therefore, seasonal differences in distributions and habitat associations of bat populations need to be considered so that effective management strategies can be devised that help conserve bats year round.
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Bristow, Kirby D., Larisa E. Harding, Richard W. Lucas, and Thomas C. McCall. "Influence of fire severity and vegetation treatments on mule deer (Odocoileus hemionus) winter habitat use on the Kaibab Plateau, Arizona." Animal Production Science 60, no. 10 (2020): 1292. http://dx.doi.org/10.1071/an19373.
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Context Wildfire and vegetation treatments affect mule deer (Odocoileus hemionus) populations across the western United States. However, the relative influence of fire and treatments on habitat use by mule deer in Arizona is not well defined. Aims We examined locations of mule deer on the Kaibab Plateau in northern Arizona, so as to determine the influence of vegetation treatments and wildfire severity on deer habitat-use patterns across their winter range where fires and treatments had occurred previously. Methods We used locations (n = 11297) from 21 adult female mule deer fitted with global positioning system collars to model probability of use as a function of habitat covariates. Key results The best model describing winter-range habitat use by mule deer on the Kaibab Plateau included covariates describing the age of vegetation treatments and fire severity. Increased deer use in winter was associated with areas of lower terrain ruggedness and reduced snow depths. Deer use also increased in areas that experienced a higher average fire severity, resulting in decreased vegetation heights. Among treatment age classes, deer use was greatest in areas containing vegetation treatments that were ≤6 years old, but negatively associated with treatments that were >6 years old. Conclusions Vegetation treatments designed to remove or reduce less palatable tree and shrub species to improve forage conditions may increase the use of winter habitats by deer on the Kaibab Plateau. Similarly, prescribed fire and rangeland treatments designed to return areas to a more natural fire regime and, thereby, generate new plant growth, may improve winter-range habitat conditions for mule deer. Implications Similar treatment strategies may also benefit mule deer populations throughout the western USA, by improving forage conditions on critical habitats and reducing the potential for catastrophic wildfire.
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Murray, Dennis L., Stan Boutin, and Mark O'Donoghue. "Winter habitat selection by lynx and coyotes in relation to snowshoe hare abundance." Canadian Journal of Zoology 72, no. 8 (August 1, 1994): 1444–51. http://dx.doi.org/10.1139/z94-191.
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We examined the relationship between winter habitat selection among lynx (Lynx canadensis) and coyotes (Canis latrans) and relative snowshoe hare (Lepus americanus) abundance by tracking in snow during three winters. Hare numbers were higher in dense spruce (Picea glauca) than in other habitats in 1987–1988, and both predator species selected that habitat in that year. In 1988–1989, hare distribution was similar among habitats, and both predators used spruce habitats relative to their availability. In 1989–1990, hare numbers were also similar among habitats, and lynx used spruce habitats according to availability, whereas coyotes selected dense spruce. Hares were the main prey of both species, and the distribution of hares chased and killed by lynx was similar to that predicted by habitat use. Lynx hunting success was also similar among habitats. In comparison, coyotes chased and killed more hares than expected and had higher hunting success in dense spruce. Snow was shallower and harder in all spruce habitats used by coyotes than in those travelled by lynx. This suggests that coyotes were more selective of snow conditions than lynx, probably as a result of their high foot-load (ratio of body mass to foot area) relative to that of hares. Coyotes scavenged more often than lynx, but neither species seemed to select habitats on the basis of carcass availability. We concluded that high hare densities influenced selection of dense spruce by both species in 1987–1988, and that coyotes may also have chosen habitats on the basis of hunting success and snow conditions.
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McMahon, Thomas E., and Gordon F. Hartman. "Influence of Cover Complexity and Current Velocity on Winter Habitat Use by Juvenile Coho Salmon (Oncorhynchus kisutch)." Canadian Journal of Fisheries and Aquatic Sciences 46, no. 9 (September 1, 1989): 1551–57. http://dx.doi.org/10.1139/f89-197.
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Winter habitat use by juvenile coho salmon (Oncorhynchus kisutch) varied with cover type and flow level in outdoor stream channels. Cover utilization and the number of fish remaining in stream channels increased significantly as cover complexity increased. Most fish emigrated during a simulated freshet unless the most complex cover (low velocity, shade, and wood debris combined) was available. At both high and low flows, emigration occurred primarily during the rapid decline in light levels at twilight. Most coho formed aggregations beneath cover, exhibiting feeding and aggression at temperatures as low as 2.5 °C. We conclude that (1) social interactions, in concert with habitat features, influence the abundance of coho salmon within specific stream habitats in winter, and (2) structural complexity of wood debris is an important consideration for management practices designed to protect or enhance winter habitat for this species.
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Carswell, Brendan M., Roy V. Rea, David Rusch, and Chris J. Johnson. "The influence of the root diseases Armillaria solidipes and Inonotus sulphurascens on the distribution of mule deer during winter." Forestry: An International Journal of Forest Research 94, no. 4 (March 3, 2021): 492–501. http://dx.doi.org/10.1093/forestry/cpab002.
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Abstract Armillaria (Armillaria solidipes) and laminated root diseases (Inonotus sulphurascens) are two wide-ranging fungal pathogens that occur in the southern half of British Columbia (BC), Canada, and can infect economically and biologically important tree species such as interior Douglas-fir (Pseudotsuga menziesii var. glauca). In northern, temperate locations, Douglas-fir forests serve as winter habitat for ungulates. When these fungal infections are in Douglas-fir forests, core components of winter ranges are altered, including canopy cover, snowpack and understory vegetation. In this study, we investigated how Rocky Mountain mule deer (Odocoileus hemionus hemionus) of central BC used winter range habitats that included root disease (A. solidipes and I. sulphurascens) centres. We used remote camera-traps to collect data from September 2017 to April 2019, and we assessed those habitats in which the cameras were located during the summer and winter of 2018. We used logistic regression and an information theoretic approach to test a series of factors hypothesised to influence the use of root disease centres by mule deer. Our results show that mule deer use root disease centres less than control forests as well as negatively respond to the deeper snow packs found in root disease centres, especially in late winter. Our cameras also detected higher vertebrate diversity in root disease centres. We suggest that forest policy-makers should acknowledge heterogeneous habitat features such as root disease centres within ungulate winter ranges and consider adjusting estimates of habitat capability for deer based on our findings.
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Kamler, Jan F., and Philip S. Gipson. "Space and Habitat Use by Male and Female Raccoons, Procyon lotor, in Kansas." Canadian Field-Naturalist 117, no. 2 (April 1, 2003): 218. http://dx.doi.org/10.22621/cfn.v117i2.685.
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We monitored 12 radio-tagged adult Raccoons (Procyon lotor) from an unexploited population in northeastern Kansas to determine intersexual differences in space and habitat use. Home ranges (mean ± SE) of males were relatively large (266 ± 14 ha) and mutually exclusive, whereas home ranges of females were relatively small (122 ± 52 ha) and overlapped extensively. Sizes of home ranges were smaller (P < 0.05) in winter than summer for both sexes, although females reduced their home ranges more than males. Females used more grassland habitats than males during summer (P < 0.05), whereas males used more grassland habitats than females during winter (P < 0.05). Seasonal differences in habitat selection was detected for females (P < 0.05), but not males. Intersexual differences in space and habitat use were likely related to different behavioral strategies employed by male and female Raccoons.
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Smith, Paul G. R. "Winter Bird Use of Urban and Rural Habitats in Ontario." Canadian Field-Naturalist 117, no. 2 (April 1, 2003): 173. http://dx.doi.org/10.22621/cfn.v117i2.679.
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This study examined variation in winter bird diversity, abundance, biomass and species and guild composition on plots in farmland, rural forests, mixed rural habitat, cities and three categories of urban natural areas in southern Ontario. Small (<20 g), insectivorous, upper canopy, bark foraging and forest species were more prevalent in rural mixed habitat, urban natural areas and especially rural forests. Larger (20-100 g), ground feeding and omnivorous birds typified cities and farms. Many bird species classified as forest, forest edge and field species during summer also favored these same habitats during winter. The 52 sample plots can be accurately classified into the seven habitat categories through discriminant analysis using the percentages of small species, insectivores, forest species and alien species. Urban natural areas, forests and mixed rural habitat showed the highest diversity while cities and farms showed the lowest diversity. Both bird abundance and biomass were highest in urban natural areas with open water and urban residential and commercial areas, whereas both were lowest in farmland.
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Aycrigg, Jocelyn L., Adam G. Wells, Edward O. Garton, Buck Magipane, Glen E. Liston, Laura R. Prugh, and Janet L. Rachlow. "Habitat selection by Dall’s sheep is influenced by multiple factors including direct and indirect climate effects." PLOS ONE 16, no. 3 (March 18, 2021): e0248763. http://dx.doi.org/10.1371/journal.pone.0248763.
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Arctic and boreal environments are changing rapidly, which could decouple behavioral and demographic traits of animals from the resource pulses that have shaped their evolution. Dall’s sheep (Ovis dalli dalli) in northwestern regions of the USA and Canada, survive long, severe winters and reproduce during summers with short growing seasons. We sought to understand the vulnerability of Dall’s sheep to a changing climate in Lake Clark National Park and Preserve, Alaska, USA. We developed ecological hypotheses about nutritional needs, security from predators, energetic costs of movement, and thermal shelter to describe habitat selection during winter, spring, and summer and evaluated habitat and climate variables that reflected these hypotheses. We used the synoptic model of animal space use to estimate parameters of habitat selection by individual females and calculated likelihoods for ecological hypotheses within seasonal models. Our results showed that seasonal habitat selection was influenced by multiple ecological requirements simultaneously. Across all seasons, sheep selected steep rugged areas near escape terrain for security from predators. During winter and spring, sheep selected habitats with increased forage and security, moderated thermal conditions, and lowered energetic costs of movement. During summer, nutritional needs and security influenced habitat selection. Climate directly influenced habitat selection during the spring lambing period when sheep selected areas with lower snow depths, less snow cover, and higher air temperatures. Indirectly, climate is linked to the expansion of shrub/scrub vegetation, which was significantly avoided in all seasons. Dall’s sheep balance resource selection to meet multiple needs across seasons and such behaviors are finely tuned to patterns of phenology and climate. Direct and indirect effects of a changing climate may reduce their ability to balance their needs and lead to continued population declines. However, several management approaches could promote resiliency of alpine habitats that support Dall’s sheep populations.
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Maki-Petäys, A., T. Muotka, A. Huusko, P. Tikkanen, and P. Kreivi. "Seasonal changes in habitat use and preference by juvenile brown trout, Salmo trutta, in a northern boreal river." Canadian Journal of Fisheries and Aquatic Sciences 54, no. 3 (March 1, 1997): 520–30. http://dx.doi.org/10.1139/f96-311.
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By means of electrofishing, we examined seasonal and size-class variation in habitat preference by juvenile brown trout (Salmo trutta) in a third-order river in northern Finland. Larger trout preferred deeper stream areas than young-of-the-year fish. At the onset of winter, all trout size-classes moved into shallower water, but this mainly reflected seasonal variation in habitat availability. In winter, trout preferred slowly flowing stream areas, whereas in other seasons the mean water velocities used by trout parallelled habitat availability. In summer and autumn, age-0 fish favoured stream areas with large amounts of aquatic vegetation to provide cover. The largest trout (16-22 cm) occupied habitats with little cover throughout the year, and in winter, all trout avoided areas with high instream cover. In summer, all size-classes preferred small substrates, whereas in winter, areas with cobble-boulder substrates were preferred, especially by trout larger than 10 cm. Wintering trout often shelter among the interstitial spaces of coarse substrates, and to facilitate the survival of juvenile trout through winter, stream management programmes need to ensure that such particles are abundantly available in trout wintering areas.
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Gjerde, Ivar. "Cues in Winter Habitat Selection by Capercaillie. I. Habitat Characteristics." Ornis Scandinavica 22, no. 3 (July 1991): 197. http://dx.doi.org/10.2307/3676590.
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Kinley, Trevor A., Trevor Goward, Bruce N. McLellan, and Robert Serrouya. "The influence of variable snowpacks on habitat use by mountain caribou." Rangifer 27, no. 4 (April 1, 2007): 93. http://dx.doi.org/10.7557/2.27.4.323.
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Mountain caribou (Rangifer tarandus caribou) in southeastern British Columbia subsist for most of the winter on arboreal hair lichen, mostly Bryoria spp. Foraging occurs mainly in old subalpine fir (Abies lasiocarpa) forests near treeline. Here, the lower limit of Bryoria in the canopy is dictated by snowpack depth because hair lichens die when buried in snow. Bryoria is often beyond the reach of caribou in early winter, prompting caribou to move downslope to where lichen occurs lower in the canopy and other foraging modes are possible. Snowpacks are normally deep enough by late winter that caribou can reach Bryoria where it is most abundant, at high elevations. Extending this to inter-annual comparisons, Bryoria should be less accessible during late winter of low-snow years following normal winters, or of normal to low-snow years after deep-snow winters. We hypothesized that when maximum snowpack in late winter is low relative to the deepest of the previous 5 years, mountain caribou will use lower elevations to facilitate foraging (“lichen-snow-caribou” or LSC hypothesis). We tested this with late-winter data from 13 subpopulations. In the dry climatic region generally and for minor snowfall differences in wet and very wet regions, caribou did not shift downslope or in fact were at higher elevations during relatively low-snow years, possibly reflecting the ease of locomotion. The LSC hypothesis was supported within wet and very wet regions when snowpacks were about 1 m or more lower than in recent years. Elevation declined by 300 m (median) to 600 m (25th percentile) for snowpack differences of at least 1.5 m. Greater use of lodgepole pine and western hemlock stands sometimes also occurred. Management strategies emphasizing subalpine fir stands near treeline should be re-examined to ensure protection of a broader range of winter habitats used by caribou under variable snowpack conditions.
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Heroldová, M., J. Zejda, M. Zapletal, D. Obdržálková, E. Jánová, J. Bryja, and E. Tkadlec. "Importance of winter rape for small rodents." Plant, Soil and Environment 50, No. 4 (December 10, 2011): 175–81. http://dx.doi.org/10.17221/4079-pse.
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Winter rape stands are important habitat for the common vole (Microtus arvalis) and the pygmy field mouse (Apodemus microps). In autumn, the common vole is dominant in this habitat (D = 75%) and reproduces in it (17% of population). This species also dominates the small mammal community of winter rape in early spring (D = 87%), and its reproduction begins in this habitat early; under suitable meteorological conditions 44% of the population of common vole reproduce in March. Analyses of the spring and autumn diet of M. arvalis in winter rape have shown that green leaves of this species form the dominant component of its diet. During the period when the rape crop is ripening, the population abundance of the common vole decreases as green food at ground level decreases. The pygmy field mouse (A. microps) has a contrasting response to winter rape, and it is almost absent from the rape crop from autumn to late spring. However, when winter rapeseeds begun to ripen, the pygmy field mouse concentration in this habitat is in large numbers (dominance D = 76%) and rapeseeds dominate its diet (v% = 72). After the harvest of winter rape, when shed seeds begin to grow, both small mammal species live for some weeks on rape plots.
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Warburg, M. R., and Gad Degani. "Variations in brood size and birth rates of Salamandra salamandra (Amphibia, Urodela) from different habitats in northern Israel." Amphibia-Reptilia 16, no. 4 (1995): 341–49. http://dx.doi.org/10.1163/156853895x00424.
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AbstractOvoviviparous births of larvae of Salamandra salamandra (L) were compared from a number of disjunct habitats in northern Israel, at the south-eastern limit of the Palearctic distribution of the species. The numbers, period and rate at which larvae were born varied between different habitats. In one winter pond, 90±11 larvae per brood were born at a rate of 5 per hour during December-January; in another pond, broods of 114±13 were born at 4 per hour during November-January; in a third, 112±15 were born at a rate of 4 per hour during November-December. In a perennial spring habitat, 68±2 larvae per brood were born at a rate one per hour during February-March, while in a stream habitat, brood size was 55±10 larvae, born at two per hour over the whole year. There were no significant differences in size between larvae from different habitats. Adjustments in birth parameters of larvae born in winter ponds indicate adaptation to an unpredictable habitat.
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Heggenes, Jan, Thomas G. Northcote, and Armin Peter. "Seasonal Habitat Selection and Preferences by Cutthroat Trout (Oncorhynchus clarki) in a Small Coastal Stream." Canadian Journal of Fisheries and Aquatic Sciences 48, no. 8 (August 1, 1991): 1364–70. http://dx.doi.org/10.1139/f91-163.
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Habitat selection by cutthroat trout (Oncorhynchus clarki) larger than 9 cm total length was monitored during winter and summer. The trout had strong preferences for depths >25 cm and areas where instream and overhead cover exceeded 40% of the local surface area. The fish selected a variety of substrate sizes. Stream areas with mean water velocities <20 cm/s were preferred. Compared with previous studies, the trout used low-velocity areas more, and we suggest that this is due to less competitive interaction from other young salmonids. The trout used the larger pools (>20 m2) considerably less during winter than during summer. Otherwise, little seasonal variation in habitat use was found. A composite measure of water depth and cover appeared to be the most important of the measured environmental factors influencing habitat selection in the stream. The larger trout, which were presumably dominant, occupied the deepest pool areas. The trout selected spatial habitats in proportions significantly different from the available habitat, demonstrating strong habitat preferences. It is concluded that observations of habitat occupancy without considering habitat availability may give biased results.
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Remsen Jr., J. V., and F. Moore. "True Winter Range of the Veery (Catharus Fuscescens): Lessons for Determining Winter Ranges of Species That Winter in The Tropics." Auk 118, no. 4 (October 1, 2001): 838–48. http://dx.doi.org/10.1093/auk/118.4.838.
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Abstract Most recent references describe the winter range of the Veery (Catharus fuscescens) as including an extensive area from northern Colombia, Venezuela, and Guyana south to south-central Brazil. Analysis of seasonal distribution of specimen records in South America, however, shows that 91 of 105 specimens were taken during spring and fall, not winter; the remaining 14, taken from 2 December to 20 February, are all from three small areas at the periphery or south of the Amazon basin. Thus, the true winter range is almost completely south and east of the area generally described. The seasonal distribution of specimen records is consistent with observational data from South America and banding data from the Neotropics. Although those data must be treated cautiously, it appears that the true winter range of the Veery is in south-central and southeastern Brazil, an area where habitat destruction threatens many natural habitats, rather than in the relatively undisturbed areas of western Amazonia. Widespread erroneous portrayal of the winter range of the Veery seems to have been caused largely by the assumption that the species winters in South America wherever it has been recorded and by overlooking a previously published analysis of its winter distribution.
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Zhang, Min, Kuaitat Cheong, Kunfong Leong, and Fasheng Zou. "Effect of traffic noise on black-faced spoonbills in the Taipa–Coloane Wetland Reserve, Macao." Wildlife Research 39, no. 7 (2012): 603. http://dx.doi.org/10.1071/wr12060.
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Context Nearly 20% of black-faced spoonbills (Platalea minor), a globally endangered species, winter along the coasts of the Pearl River Estuary, China. However, these wintering habitats are threatened by urban development. Especially in Macao, road construction for the tourism industry has resulted in habitat deterioration. Aims Our study aimed to assess the effects of traffic noise on the distribution and behaviour of black-faced spoonbills in the Taipa–Coloane Wetland Reserve, Macao SAR. Methods We built a traffic-noise prediction model for habitat-suitability division. Then we investigated the relationship between traffic noise and diurnal of spoonbill behaviours by collecting traffic-noise data on surrounding roads and observing the activity of black-faced spoonbills in the area over two winters, from 2007 to 2009. Key results The maximum number of individuals present in a single month was 50 in the winter of 2007–08 (in February) and 52 in the winter of 2008–09 (in January). Continuous traffic noise was 46.5 and 45.4 dB(A), respectively, at roosting sites in two ecological zones. On the basis of the prediction model, only 10.8 of 30.3 ha were suitable for spoonbills, with noise levels lower than 47 dB(A). Most of the time, the spoonbills were acclimated to the traffic and were not alarmed. However, heavy trucks with a high noise level of 81.8 ± 2.3 dB(A) sometimes disrupted spoonbill behaviour. Conclusions The traffic noise around the Taipa–Coloane Wetland Reserve did exist but did not substantially affect black-faced spoonbills. For the birds mainly roosting in a quieter area, the small area of suitable habitat may indirectly limit population growth. Implications The fences around Ecological Zone I were successful in minimising visual stimuli from human activities and passing cars. To maintain the suitability of the winter habitat in Macao, restrictions on traffic flow, especially on heavy truck volume, are necessary for spoonbill conservation.
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Stirling, Ian, Dennis Andriashek, and Wendy Calvert. "Habitat preferences of polar bears in the western Canadian Arctic in late winter and spring." Polar Record 29, no. 168 (January 1993): 13–24. http://dx.doi.org/10.1017/s0032247400023172.
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ABSTRACTBetween late March and May, from 1971 through 1979, we surveyed 74,332 km2 of sea-ice habitatin the eastern Beaufort Sea and Amundsen Gulf in the western Canadian Arctic. We defined seven sea-ice habitat types and recorded sightings of polar bears and their tracks in each to determine their habitat preferences. 791 bears (including cubs) and 6454 sets of tracks were recorded. 42.3%, 39.7%, and 15.6% of the bears were seen on floe-edge, moving ice, and drifted fast-ice habitats, respectively. Significant differences in habitat preferences were shown by bears of different sexes and age classes. Adult females accompanied by cubs of the year were the only group that showed a strong preference for fast ice with drifts, probably because they could feed adequately there while avoiding adult males that might prey upon their cubs. The highest densities of seals are found in floe-edge and moving ice habitats and this likely explains the predominance of bears there. Lone adult females and females with two-year-old cubs, adult males, and subadult males were found two and one-half to four times more frequently than predicted in floe-edge habitat. Since there are no data to suggest seals are more abundant along the floe edge than in moving ice habitat, the preference of these groups of adult polar bears for the floe edge in spring may be related to reproductive behavior.
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Morris, Kelly M., Eric C. Soehren, Mark S. Woodrey, and Scott A. Rush. "Habitat-Suitability Model for the Yellow Rail (Coturnicops noveboracensis) in the Northern Gulf Coast of Alabama and Mississippi, USA." Remote Sensing 12, no. 5 (March 6, 2020): 848. http://dx.doi.org/10.3390/rs12050848.
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The yellow rail (Coturnicops noveboracensis) is a migratory bird of high conservation priority throughout its range and winters across the Atlantic and Gulf Coastal Plains regions of the southeastern United States. Although the winter ecology of this species has been recently explored, no studies have addressed their distribution and abundance in relation to suitable habitat capable of supporting this species during winter along the northern Gulf Coast of Alabama and Mississippi. The objectives of this study were to develop a habitat-suitability model for yellow rail wintering in the northern Gulf Coast of Alabama and Mississippi. We then used this model to evaluate the distribution of habitat suitable for supporting yellow rail in this geographic area. Using a multivariate approach that makes use of presence-only data through a maximum entropy framework we compared the distribution of where the focal species was observed to a reference set of the whole study area. Of the 784,657 ha over which our model was applied, only 1% (8643 ha) of this area was predicted suitable in its present condition, for supporting yellow rail in winter. Our analysis indicates that the yellow rail along the northern Gulf Coast of Alabama and Mississippi occupy a very narrow range of environmental conditions highlighting need for specific management actions to maintain and conserve suitable winter landscapes for this habitat-restricted species.
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Callicutt, James T., Heath M. Hagy, and Michael L. Schummer. "The Food Preference Paradigm: A Review of Autumn–Winter Food Use by North American Dabbling Ducks (1900–2009)." Journal of Fish and Wildlife Management 2, no. 1 (June 1, 2011): 29–40. http://dx.doi.org/10.3996/102010-jfwm-038.
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Abstract Studies describing food use (i.e., diet) of nonbreeding dabbling ducks Anas spp. are essential to understanding physiological needs of and recommending habitat management for these birds. We conducted a review of published autumn and winter food-use studies of dabbling ducks in North America to characterize the current state of knowledge and identify remaining research needs. We initiated our review to determine whether valuations of duck foods and the term “preference” commonly used by researchers and in waterfowl management guides (i.e., the food preference paradigm) were supported by available peer-reviewed literature. We analyzed peer-reviewed literature (1900–2009) on autumn–winter food use of dabbling ducks (n = 59 studies). Most studies (68%) used methods known to contain substantial bias including data from gizzards and hunter-collected ducks. Only 5% of published articles reliably determined food selection by concurrently measuring food use and availability, and no study determined food use at a scale appropriate for winter home ranges of dabbling ducks. In some habitats commonly managed for waterfowl (e.g., agricultural lands), few if any collections of ducks are available to obtain data on food use. The limited geographic and habitat scope of unbiased food use and selection studies for dabbling ducks during autumn and winter suggests that the food-preference paradigm found in waterfowl management literature is not supported by empirical evidence and that managers must continue to use best judgment in managing foraging habitats for waterfowl. Researchers and conservation planners should aim to reduce uncertainty regarding the value of waterfowl foods by conducting contemporary food-selection studies using unbiased collection and processing methodologies. Further, we suggest future researchers conduct concurrent behavioral observations, habitat use, and food selection studies within winter home ranges of dabbling ducks to aid managers in meeting the nutritional requirements of dabbling ducks during autumn and winter in North America.
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Jayawardana, J. M. C. K., Martin Westbrooke, Michael Wilson, and Cameron Hurst. "Macroinvertebrate communities in willow (Salix spp.) and reed beds (Phragmites australis) in central Victorian streams in Australia." Marine and Freshwater Research 57, no. 4 (2006): 429. http://dx.doi.org/10.1071/mf05139.
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Exotic willows (Salix spp.) are widespread riparian tree species of rivers in temperate Australia and New Zealand. Despite being considered as a weed of national significance, little is known about the habitat value of willows and the impact on aquatic biota of vegetation change following willow management programmes. Macroinvertebrate fauna in root habitats of willows and Phragmites australis habitats were examined in three central Victorian rivers to understand the effect of such littoral habitat changes on macroinvertebrates. Data were analysed using Partially Nested Factorial ANOVA with season, river and habitat as main effects. Habitat structure had a significant effect (P < 0.05) on macroinvertebrate community assemblage. However, effect of habitat was not consistent among seasons. The greatest community differences among habitats were observed during winter and least separation during autumn. Taxa responsible for community differences among habitats were also identified. Species richness and abundance did not show consistent variation among habitats over different rivers or seasons. This study provided some indication of the macroinvertebrate community changes that would take place in situations where riparian vegetation changes takes place from willows to P. australis.
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Poole, Kim G., Rob Serrouya, Irene E. Teske, and Kevin Podrasky. "Rocky Mountain bighorn sheep (Ovis canadensis canadensis) winter habitat selection and seasonal movements in an area of active coal mining." Canadian Journal of Zoology 94, no. 11 (November 2016): 733–45. http://dx.doi.org/10.1139/cjz-2016-0069.
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Winter is an important period for most mountain ungulates due to limited availability of preferred forage and costs associated with travel through deep snow. We examined winter habitat selection by Rocky Mountain bighorn sheep (Ovis canadensis canadensis Shaw, 1804) where four large, open-pit coal mines are in operation. Sheep in this area generally winter at high elevation on windswept, south-facing native grasslands. We used GPS collars and Resource Selection Function analysis to examine movements and habitat selection. A majority (79%) of the sheep were migratory and fidelity to winter ranges was high (88%). Sheep showed low use (∼10%–20%) of mine areas between November and April, followed by increased use peaking at 60%–65% in September–October. Wintering sheep were positively associated with high elevations, closeness to escape terrain, and warmer aspects. High-elevation, native grasslands were the highest ranked cover class. Most sheep that used mine areas during winter used reclaimed habitats, primarily reclaimed spoils and pits. Primary winter ranges comprised 4.3% of merged sheep range, emphasizing the limited amount of occupied winter ranges within the landscape. Disturbance to native winter range resulting from development should be minimized or be conducted in a manner that effectively manages and (or) mitigates the impacts.
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Hwang, Yeen Ten, Serge Larivière, and François Messier. "Local- and landscape-level den selection of striped skunks on the Canadian prairies." Canadian Journal of Zoology 85, no. 1 (January 2007): 33–39. http://dx.doi.org/10.1139/z06-192.
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We examined the seasonal landscape and habitat use patterns of striped skunks ( Mephitis mephitis Schreber, 1776). We tracked 52 male and 72 female skunks from September 1999 to June 2003 in Saskatchewan, Canada. At the local level, den structures differed by sex and season. In autumn/winter, all skunks preferred buildings, whereas in spring/summer females selectively used underground burrows and rock piles for parturition and rearing of young, and males used aboveground retreats. Den sites were closer to crop fields, roads, water sources, and macrohabitat edges than random sites. At the landscape level, den sites were associated positively with weighted mean shape index of crop fields, mean patch size of water bodies, total edge of water bodies, and weighted mean fractal dimensions of grassland, woodland, and farmsteads, suggesting that wetland edges and habitat complexity are important in den selection by skunks. Compositional analysis revealed sex- and season-specific differences at the population level. Both sexes preferred grassland/pastures and farmstead habitats for establishing den sites. In autumn/winter, skunks preferred grassland/pastures for winter dens. However, in spring/summer skunks preferred farmsteads for resting sites. Our results suggest that skunks respond to landscape and habitat features surrounding den sites, and not just specific den or local habitat characteristics.
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Masero, José A., and Alejandro Pérez-Hurtado. "Importance of the Supratidal Habitats for Maintaining Overwintering Shorebird Populations: How Redshanks Use Tidal Mudflats and Adjacent Saltworks in Southern Europe." Condor 103, no. 1 (February 1, 2001): 21–30. http://dx.doi.org/10.1093/condor/103.1.21.
Full textAbstract:
Abstract The prey-size selection, foraging behavior, and intake rate of overwintering Redshanks (Tringa totanus) were studied in a supratidal-intertidal system with high intertidal densities of shorebirds (100 birds ha−1). For assessing the importance of the energy obtained in the supratidal habitat (saltworks), daily consumption in this habitat was compared with the total daily energy requirement. Redshanks passively select prey within a certain size range from those accessible on the intertidal area. Despite the high prey biomass on the mudflats, Redshanks exhibited a low intake rate during winter (0.321 kJ min−1). This low intake seems to be related to the influence of the high densities of foraging shorebirds on the behavior of prey. Although intake rate was higher in the saltworks, the majority of Redshanks did not choose to feed there in winter. This foraging pattern seems to be related to density-dependent effects in habitat occupancy, as social interactions could have kept Redshanks out of the saltworks in winter according to the predictions of the ideal-despotic model. Energy intake in the supratidal habitat contributed 23% and 82% of the total daily energy requirement in winter and the pre-migration period, respectively. Redshanks were able to meet the total daily energy requirement during the pre-migration period by increasing foraging time in the saltworks. The availability of supratidal foraging habitats seems to contribute significantly to the maintenance of the population of overwintering Redshanks.
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Oehler, James D., and John A. Litvaitis. "The role of spatial scale in understanding responses of medium-sized carnivores to forest fragmentation." Canadian Journal of Zoology 74, no. 11 (November 1, 1996): 2070–79. http://dx.doi.org/10.1139/z96-235.
Full textAbstract:
Increased predation has been suggested as a proximate factor causing the decline of vertebrate diversity in many human-altered landscapes. Previous studies on this topic have provided conflicting results, perhaps as a consequence of the limited spatial scale used in these investigations. We incorporated a multiscaled approach (using site, plot (1.44 km2), and landscape (54 km2)) to investigate the distribution of activity of medium-sized carnivores relative to habitat edges and the numeric responses of these predators to habitat diversity. Among the taxa surveyed, raccoons (Procyon lotor) did not show an affinity for habitat edges at any spatial scale. However, raccoons were more abundant in landscapes characterized by a diversity of cover types. Free-ranging domestic dogs (Canis familiaris) and cats (Felis domesticus) did not respond to the proximity of habitat edges in summer but showed a strong affinity for edge habitats (especially those associated with human dwellings) during winter. Wild canids (Vulpes vulpes and Canis latrans) also selected sites in close proximity to edges in winter and were more abundant in diverse landscapes. Although human-dominated habitats (agricultural areas, grass–brushland, and developed sites) represented only 7–27% of the three landscapes studied, populations of generalist predators (raccoons and wild canids) increased as landscapes became more diverse. As a result, even moderate levels of habitat fragmentation may elevate predation rates and subsequently alter the composition of prey communities.
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Carruthers, D. R., S. H. Ferguson, R. D. Jakimchuk, and L. G. Sopuck. "Distribution and habitat use of the Bluenose caribou herd in mid-winter." Rangifer 6, no. 2 (June 1, 1986): 57. http://dx.doi.org/10.7557/2.6.2.583.
Full textAbstract:
The mid-winter distribution and densities of the Bluenose caribou herd were compared with previous surveys over six years and were similar in all years except 1981 when exceptionally mild weather prevailed. Differences in group size, distribution and habitat use between sexes were noted in 1983. Caribou were distributed disproportionately to availability of vegetation types and used lakes significantly more than expected based on their occurrence. Male groups used conifer cover more than did female-calf groups which used open areas (lakes, fens, bogs) more than males. Cow-calf groups chose areas with a higher small lake density compared to lake density generally available. Generally caribou preferred habitat between 200 and 300 m in elevation with high densities of lakes less than 1 km2 in size. Snow depths and hardness were greater in most unoccupied habitats than in occupied habitats. Wolves were associated with high densities of cow/calf groups.
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P. Catterall, Carla, Mark B. Kingston, and Kate Park. "Use of remnant forest habitat by birds during winter in subtropical Australia: patterns and processes." Pacific Conservation Biology 3, no. 3 (1997): 262. http://dx.doi.org/10.1071/pc970262.
Full textAbstract:
The south-east Queensland region of subtropical Australia supports a high diversity of landbird species, many of which are migrants which visit lowland areas during winter. However, lowland habitats have been impacted by clearing and fragmentation of native forest types within the past 170 years. This paper considers the implications of loss and fragmentation of lowland eucalypt forests for birds in winter, by comparing the proportionate density of twelve selected species across 49 different cases representing a variety of structural habitat differences. There was little fragmentation effect on forest-dependant winter immigrant species down to about 10 ha. The smallest remnants had reduced proportionate abundances of forest-dependent species together with elevated abundances of two other species: Noisy Miner and Australian Magpie. Similar shifts in species composition occurred in association with a variety of types of change in native eucalypt forest, all involving alteration to physical structure incorporating reduction of foliage cover (at forest edges, in areas without understorey, in regenerating forest, on slopes and ridges, and after fires). We consider the ecological processes that might underlie these patterns, and suggest that: (1) habitat selection, possibly mediated and/or reinforced by interference competition from Noisy Miners, is a key process in the study system in winter; (2) habitat loss, rather than fragmentation, is likely to be the main cause of regional declines in forest-dependent winter migrants; and (3) the management of habitat for winter migrant birds within lowland eucalypt forests of this region should focus on maintaining and improving: (a) the overall percentage of lowland area covered by native forest, and (b) factors associated with the structural integrity (canopy and understorey cover, fire frequency, retention of complete microtopographic gradients) of remnant forest areas irrespective of their size, at least down to about 10 ha.
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Paterson, J. E., B. D. Steinberg, and J. D. Litzgus. "Generally specialized or especially general? Habitat selection by Snapping Turtles (Chelydra serpentina) in central Ontario." Canadian Journal of Zoology 90, no. 2 (February 2012): 139–49. http://dx.doi.org/10.1139/z11-118.
Full textAbstract:
Habitat selection is the disproportionate use of habitat compared with availability. Many studies have focused on specialists, but few have considered habitat selection in populations that are generalists, which can be composed of generalist individuals or individuals that specialize on different habitats. We tested habitat selection and individual specialization in a northern population of a supposed generalist, the Snapping Turtle ( Chelydra serpentina (L., 1758)), during the active season and winter using telemetry. Habitat selection was tested at two spatial scales by comparing random points to home ranges and turtle locations using Euclidean distances. Turtles selected home ranges from the habitats available in the population range. However, at the population level, all aquatic habitats were equally preferred, and the population behaved as a generalist owing to individuals specialized on different habitats. Over half of the individuals showed evidence of individual specialization on different habitat types. Turtles did not select habitat within home ranges during the active season, but overwintering turtles chose locations that were colder than haphazard stations in the same habitats, likely to reduce metabolic costs and the risk of acidosis. These findings have implications for the management of this species at risk and for understanding the evolution of resource generalization.
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Chamberlain, D. E., A. Joys, P. J. Johnson, L. Norton, R. E. Feber, and R. J. Fuller. "Does organic farming benefit farmland birds in winter?" Biology Letters 6, no. 1 (September 9, 2009): 82–84. http://dx.doi.org/10.1098/rsbl.2009.0643.
Full textAbstract:
The generally higher biodiversity on organic farms may be influenced by management features such as no synthetic pesticide and fertilizer inputs and/or by differences in uncropped habitat at the site and landscape scale. We analysed bird and habitat data collected on 48 paired organic and conventional farms over two winters to determine the extent to which broad-scale habitat differences between systems could explain overall differences in farmland bird abundance. Density was significantly higher on organic farms for six out of 16 species, and none on conventional. Total abundance of all species combined was higher on organic farms in both years. Analyses using an information-theoretic approach suggested that both habitat extent and farm type were important predictors only for starling and greenfinch. Organic farming as currently practised may not provide significant benefits to those bird species that are limited by winter food resources, in particular, several declining granivores.