Factors Influencing Habitat Selection Research Articles

Factors affecting spatial occupancy and local abundance of the Forest Thrush, Turdus lherminieri, in Guadeloupe forests

The Forest Thrush (FT), Turdus lherminieri, is a secretive, ground-dwelling forest bird species of conservation concern, endemic to only four Caribbean islands. Factors influencing habitat selection and abundance by FT have been seldom documented so far. We assessed variation in the presence and abundance of FT in various forested habitats in Guadeloupe. To that end, we deployed 5-camera-trap arrays over 14 days on 24 different survey stations resulting in 1680 trap days. We observed FT more frequently at camera trap stations where rainforest dominated, with local abundance declining with increasing canopy openness. Furthermore, temperature was the most important factor affecting the presence of FT at our study sites. FT was essentially diurnal, with some activity at dawn and dusk. We document for the first-time spatial co-occurrence between FT and potential mammal predators. FT co-occurred positively with rats and negatively with cats. Although FT is globally listed as near threatened by IUCN, the species the species appeared to be relatively abundant in Guadeloupe, possibly as a consequence of the suspension of hunting since 2014 and/or the almost total protection of the Guadeloupe tropical rainforest. We recommend the use of camera traps to improve knowledge for the conservation status of the species in other part of its area of distribution and to provide additional information on the potential impact of exotic predatory mammals.

Ensemble modelling the distribution and habitat suitability of wild goat Capra aegagrus in southwestern Iran

ABSTRACT Increasing anthropogenic pressures have caused drastic population decline of wild goats Capra aegagrus. The study aim was to determine habitat suitability and explore the factors influencing habitat selection and dispersal of wild goats in the Khaeiz and Sorkh protected area, southwestern Iran. We utilized ensemble modelling based on 25 replications of 10 species distribution models GLM (generalized linear model), GAM (generalized additive model), GBM (gradient boosting model), CTA (classification tree analysis), FDA (flexible discriminant analysis), ANN (artificial neural network), MARS (multivariate adaptive regression spline), RF (random forest), MaxEnt (maximum entropy), SRE (surface range envelope). Wild goat occurrence data were collected from 2019 to 2020 and related to five variables: predator distribution, slope, distance from road, distance from water resources, and normalized difference vegetation index (NDVI). We found that distribution of predators, slope, distance from water resources and distance from roads were the most important predictors of potential habitats for wild goats. The least important variable was NDVI. Probabilistic predictions suggest that only 5.89% of the area was highly suitable habitat, whereas 46.24% was unsuitable. Ensembling individually classified presence/absence maps further indicates that 79.72% of the study area was certainly unsuitable while only 8.06% was certainly suitable for wild goats. The results can help wildlife managers and policymakers work towards conservation and management goals and decreasing the conflicts between wildlife and humans.

Abundance and Habitat Preference of the Genus Euplectes in Protected and Non protected Habitats of Jos East Plateau State, Nigeria

The knowledge on the factors influencing habitat selection is of uttermost importance because it guides the development of conservation action plan for species. Till date, there is no baseline study on the genus Euplectes in Northern Nigeria thus, an attempt to investigate the habitat preference of the genus was carried out in Amurum Forest Reserve and the nonprotected habitats of Fobur. Line transects of 200m were randomly laid across the study sites. The abundance of Bishop species was highest in farmland compared to grassland and rocky outcrop. Therefore, the number of the species was significantly different between habitats (F2, 573 = 5.454, P = 0.0015). There was a significant relationship between flock size and number of seeds across habitat types. Number of individual birds increased with increase in seed number (F1, 57 = 21687.786, P < 0.001). With the exception of grass height, there was a highly significant difference in relation to vegetation variables taken between plots where Bishop species were sighted and the random points where they were not seen (P < 0.001). The finding suggests that farmlands should be integrated into conservation plan in the nonprotected area based on the high population of the genus recorded.

Factors Influencing Habitat Selection of Three Cryptobenthic Clingfish Species in the Shallow North Adriatic Sea

Cryptobenthic fishes were often overlooked in the past due to their cryptic lifestyle, so knowledge of their ecology is still incomplete. One of the most poorly studied taxa of fishes in the Mediterranean Sea is clingfish. In this paper we examine the habitat preferences of three clingfish species (Lepadogaster lepadogaster, L. candolii, and Apletodon incognitus) occurring in the Gulf of Trieste (Northern Adriatic). The results show that all three species have a cryptic lifestyle and are well-segregated based on their depth distribution and macro- and microhabitat preferences. L. lepadogaster inhabits shallow waters of the lower mediolittoral and upper infralittoral, where it occurs on rocky bottoms under stones. L. candolii similarly occurs in the rocky infralittoral under stones, but below the lower distribution limit of L. lepadogaster, and in seagrass meadows, where it occupies empty seashells. Such hiding places in seagrass meadows are also occupied by A. incognitus, which mostly occurs below the lower distribution limit of L. candolii. Despite the overlap of depth and macrohabitat, the probability of individuals of two species encountering each other or competing in the same habitat is low when the depth range is combined with the microhabitat preferences of these species.

Prioritizing areas for conservation outside the existing protected area network in Bhutan: the use of multi-species, multi-scale habitat suitability models

ContextUnderstanding the environmental and anthropogenic factors influencing habitat selection of multiple species is a foundation for quantifying human impacts on biodiversity and developing effective conservation measures.ObjectivesTo determine the effect of multiple scales of environmental/topographic and anthropogenic variables and landscape patterns on habitat suitability of terrestrial mammals in Bhutan, assess the effectiveness of the current protected area network, identify areas of high species richness outside of the existing protected area, and evaluate the potential effectiveness of indicator and umbrella species for conservation planning.MethodsWe modelled multi-scale habitat selection of sixteen species of terrestrial mammals across Bhutan using data from a nation-wide camera trap survey. We used the predicted species distribution maps to assess the multi-species conservation effectiveness of the existing protected area network. We performed simulations to identify high priority areas for multiple species based on their habitat suitability, proximity to existing protected areas and overall connectivity within the predicted distribution of species. We used correlation analysis among predicted occurrence maps and multivariate cluster analysis to identify potential indicator species. We evaluated the potential utility of each species as umbrella species by assessing how well optimal protected areas for that species would protect suitable habitat for all 16 species simultaneously.ResultsProtected areas and forest cover were strongly associated with habitat use of most modelled species. Additionally, topographical features, like terrain roughness and slope position, contributed to habitat selection of multiple species, but often in different ways. Environmental and topographical variables were mostly selected at medium to broad scales. Anthropogenic variables (agriculture and built-up areas) were negatively associated with habitat suitability of most species at both fine and broad scales. Conservation effectiveness assessment of existing protected areas found protected areas in south-central Bhutan have high effectiveness in terms of both mean and total richness protected. Similarly, biological corridors in the south-central region offered high mean richness protection. Our simulation of optimal areas for additional protection found areas abutting protected areas in southern Bhutan offered high relative species richness protection. Our umbrella species analysis found muntjac, wild pig, serow, sambar and Asian golden cat are the most effective umbrella species for broader biodiversity protection. Our indicator species analysis found tiger, gaur, dhole, clouded leopard, Asian black bear and common leopard as effective indicator species.ConclusionsThis study highlights the need to protect optimally located species-rich areas outside the current protected areas. This kind of multi-species habitat assessment provides important information to optimize future conservation and development plans at national and regional scales.

梵净山保护区食蟹獴(Herpestes urva)栖息地选择与日活动节律

野生动物栖息地选择与日活动节律是其长期生存适应的结果，对物种生存繁衍具有重要意义。2017年4月至2019年7月，组在梵净山国家级自然保护区内布设了41台红外相机进行监测和研究。基于红外相机监测数据，利用占域模型（Occupancy model）和核密度估计方法（Kernel density estimation），对食蟹獴（Herpestes urva）的栖息地选择和日活动节律进行了分析探讨。结果表明：（1）食蟹獴在常绿落叶阔叶混交林出现频率最高，在落叶阔叶林和针阔混交林出现频率最低，并集中出现于中低海拔区域；（2）在8种栖息地选择影响因素中，具有重要影响的因子为针阔混交林、海拔、水源地和常绿阔叶落叶混交林4种。其中，食蟹獴明显选择常绿阔叶落叶混交林（β=1.79±1.19 SE），明显排斥针阔混交林（β=-1.93±1.30 SE），海拔高度、离水源地的距离与占用率呈明显负相关；（3）年活动节律显示，食蟹獴在雨季活动明显增多，4-9月的活动频次在全年活动中占比达83.50%；（4）食蟹獴为完全昼行性物种，日活动时间分配较为平均，在9：00-10：00和13：00-14：00活跃度低，日活动高峰出现在11：00-13：00。梵净山地区作为食蟹獴分布区的北端，其典型的山地气候特征和植被类型与其他分布区存在显著差异，并面临不同的捕食风险和不同程度的人为干扰，食蟹獴对栖息地的选择方式和活动节律也出现了适应性的变化。;Habitat selection and daily activity patterns, resulted from environment adaptation, are of great significance to the survival and reproduction of wild animals. From April 2017 to July 2019, our research team set up 41 infrared cameras in Fanjingshan National Nature Reserve for monitoring the wildlife in the area. Based on the data acquired from Herpestes urva, the habitat selection and daily activity patterns were analyzed and discussed by using the occupancy model and kernel density estimation method. The results showed that:(1) The appearance of Herpestes urva was concentrated in the low and middle altitude area with the highest frequency in the evergreen deciduous broad-leaved forest, and the lowest frequency in the deciduous broad-leaved forest and theropencedrymion. (2) Among 8 factors influencing habitat selection, altitude, water source, theropencedrymion, and evergreen deciduous broad-leaved forest are of great significance. Herpestes urva prefers living in the evergreen deciduous broad-leaved forest (β=1.79±1.19 SE), and obviously repels the theropencedrymion (β=-1.93±1.30 SE). Altitude and water source distance significantly negatively correlate to occupancy rate. (3) The annual activity patterns show that the activity of Herpestes urva significantly increased in rainy season, and the activity frequency from April to September accounted for 83.50% of the annual activity. (4) The Herpestes urva is a complete diurnal species. Its daily activity time is relatively equally distributed with the lows at 9:00-10:00 and 13:00-14:00, and the peaks at 11:00-13:00. As the northern part of the Herpestes urva distribution area, the climate and vegetation types of Fanjingshan area are significantly different from other distribution areas. Herpestes urva living in this area are faced with different predators and certain degree of human interference, which incurs adaptive changes to their habitat selection and daily activity patterns.

Habitat selection of the Common Quail (Coturnix coturnix) in an intensively managed agricultural environment

Abstract This study investigated the habitat selection of the Common Quail (Coturnix coturnix) during the breeding season of 2014 in an intensively managed agricultural environment (LAJTA Project, North-West Hungary). In order to assess the habitat preferences of the Common Quail, habitat composition around occupied plots were compared with unoccupied control plots. To characterize the habitat, a total of 11 variables related to vegetation structure and diversity, food availability and landscape were quantified. Multivariate methods (PCA and GLMs) were used to distinguish the main factors influencing habitat selection and to model the presence of the Common Quail. Based on our results, in the LAJTA Project, high probability of Common Quail presence can be predicted in plots with higher herbaceous cover and more abundant arthropod communities. The network of ecotone habitats, particularly the proximity to woody habitats, also appeared to have significant importance during the breeding season.

There goes the neighborhood: White-crowned Sparrow nest site selection and reproductive success as local density declines

ABSTRACT Changes in climate, vegetation, and land use are recognized as important drivers of changes in the distribution and abundance of wildlife. However, the behavioral and demographic mechanisms through which these changes affect populations have received less attention. Identifying these mechanisms is an important component of predicting the impacts of increasing environmental change. We used 30 yr of nest monitoring data at a study site where White-crowned Sparrow (Zonotrichia leucophrys) breeding density declined 85% to evaluate factors influencing habitat selection and reproductive success. Rapid secondary plant succession occurred at our study site, but the rate of change was faster in some areas than others. White-crowned Sparrows exhibited strong patterns of nest site selection, preferring open shrub vegetation and avoiding forest. As a result, many parts of the study area that were used for nesting early in the study period were no longer occupied by the end of the study period. Over the cours...

Six new subterranean freshwater gastropod species from northern Albania and some new records from Albania and Kosovo (Mollusca, Gastropoda, Moitessieriidae and Hydrobiidae).

During a field trip to the western part of the Balkan Peninsula in 2016, investigations of several caves and karstic springs revealed six new gastropod species living in subterranean waters and resulted in some note-worthy faunistic records. Five of the new species are assigned to the genus Paladilhiopsis Pavlović, 1913, namely P. prekalensis sp. n., P. lozeki sp. n., P. szekeresi sp. n., P. wohlberedti sp. n., P. falniowskii sp. n. and one to the genus Plagigeyeria Tomlin, 1930, namely P. steffeki sp. n. New Albania and Kosovo distribution records are given for Iglica illyrica Schütt, 1975, Plagigeyeria zetaprotogona Schütt, 1960, Vinodolia matjasici (Bole, 1961), and the first georeferenced record is given for Saxurinator schlickumi Schütt, 1960. The most important environmental factors influencing habitat selection of these subterranean freshwater gastropods are briefly discussed.

Habitat selection in a reintroduced population: social effects differ between natal and post‐release dispersal

AbstractUnderstanding the factors driving dispersal behaviour and habitat selection in reintroduced populations can be critical to reintroduction success. Social factors in particular can influence habitat selection, for example through conspecific attraction, and this can have both positive and negative effects on reintroduction success, particularly where multiple releases occur. In addition, little is known about how habitat selection differs between natal and post‐release dispersal within species. Often it is assumed that information from a species’ natal dispersal preferences and patterns can act as a guide for predicting post‐release dispersal behaviour, but no studies to date have examined this. We examine the factors influencing habitat selection during both natal and post‐release dispersal in a reintroduced hihi (stitchbird, Notiomystis cincta) population using species distribution models. We demonstrate a strong social effect in habitat selection of natal dispersers bred at the release area (largely the offspring of founders), yet find no social effect in habitat selection of juveniles translocated 2 years after the first releases occurred. In addition, we establish that environmental variables are important in habitat selection in both groups. We suggest (1) that consideration of social effects and conspecific attraction should play a role in planning reintroduction release strategies, especially if reinforcement releases are considered necessary, and (2) that it may not always be appropriate to assume post‐release dispersal in reintroduced populations will be driven by the same factors that influence natal dispersal.

Habitat Selection and Factors Influencing Nest Survival of Golden Eagles in South-Central Montana

Golden Eagle (Aquila chrysaetos) population trends in the western United States are unclear, but an increase in future threats is causing concern for the species. Understanding the resource requirements of Golden Eagles will be essential to the creation of an effective management approach. Yet, we currently lack sufficient information on the basic habitat requirements of Golden Eagles, which hinders creation of a successful conservation plan. We took a multiscaled approach to identify factors influencing habitat selection of breeding Golden Eagles in south-central Montana. In addition, we tested environmental factors we predicted would influence daily nest survival rates to understand environmental influences on breeding success. From the 2010–2013 nesting seasons, we located 45 nesting territories and identified 115 apparent nest initiations (defined as nests where eggs have apparently been laid). We collected 15,182 telemetry locations from 12 breeding Golden Eagles. We found that Golden Eagles selected home ranges based on the percent of intermixed shrub and grassland and terrain ruggedness. At the within-home range scale, Golden Eagles selected areas based on aspect, distance to their nest, and an interaction between proximity to prey habitat and terrain ruggedness. Despite Golden Eagle selection of rugged topography, daily nest survival was negatively influenced by topographic ruggedness. Based on our results, we suggest that to maintain breeding pairs of Golden Eagles in areas similar to our study area, management should focus on preserving adequate prey habitat in areas with rugged topography. However, territories with higher ruggedness may not be as productive; therefore, management goals should be clear and environmental factors influencing both habitat selection and reproductive success should be considered when possible.

Home range and multiscale habitat selection of threatened thin-spined porcupine in the Brazilian Atlantic Forest

The threatened and poorly known thin-spined porcupine (Chaetomys subspinosus) is endemic to the highly deforested central portion of the Atlantic Forest of eastern Brazil. In southern Bahia, anecdotal observations suggested that native forest and shade cacao (Theobroma cacao) plantations are important habitats for this species. However, no studies have examined habitat preferences. We estimated the home-range size and determined the factors influencing habitat selection at landscape, home range, and tree scales in the cacao-growing region of southern Bahia. Radiotelemetry data from 21 individuals followed for 3–25 months from April 2005 to November 2013 showed a relatively small home range (0.5–9.5 ha using minimum convex polygon methods), with males showing larger home ranges than females. Habitat selection was congruent across spatial scales, with preference for structurally complex environments at all scales. The tagged porcupines preferred trees that were large, harboring many lianas, and closer to fo...

Vegetation maps based on remote sensing are informative predictors of habitat selection of grassland birds across a wetness gradient

Vegetation is a major environmental factor influencing habitat selection in bird species. High resolution mapping of vegetation cover is essential to model the distribution of populations and improve the management of breeding habitats. However, the task is challenging for grassland birds because microhabitat variations relevant at the territory scale cannot be measured continuously over large areas to delineate areas of higher suitability. Remote sensing may help to circumvent this problem. We addressed this issue by using SPOT 5 imagery and phytosociological data. We mapped grassland vegetation in a floodplain using two methods. We (i) mapped the continuous Ellenberg index of moisture and (ii) identified 5 vegetation classes distributed across the wetness gradient. These two methods produced consistent output maps, but they also provided complementary results. Ellenberg index is a valuable proxy for soil moisture while the class approach provided more information about vegetation structure, and possibly trophic resources. In spite of the apparent uniformity of meadows, our data show that birds do not settle randomly along the moisture and vegetation gradients. Overall birds tend to avoid the driest vegetation classes, i.e. the highest grounds. Thus, vegetation maps based on remote sensing could be valuable tools to study habitat selection and niche partition in grassland bird communities. It is also a valuable tool for conservation and habitat management.

Factors Influencing Habitat Selection by Arboreal Pit Vipers

We studied factors influencing habitat selection by two arboreal species of pit viper, namely Trimeresurus malabaricus (Malabar pit viper) and T. gramineus (Bamboo pit viper). The macrohabitat of these species was classified as forest, forest edge, or open habitat. To determine microhabitat selection, a variety of features at every other snake location were measured. Whether or not the animal was found in a tree, the tree species, its height of perch, position on the branch (distal/ apical/middle), diameter of the branch, the tree canopy (thick/sparse) and vegetation of the area (thick/sparse) were recorded. Assessment of habitat was done to determine how patterns of habitat use vary seasonally. Shaded ambient (air) temperatures and humidity were recorded. Data pertaining to 90 individuals of T. malabaricus and 100 individuals of T. gramineus were recorded. Trimeresurus malabaricus selected home ranges that included areas with thick vegetation and were encountered at regions of higher altitude. Neither of the species was found in open habitats. Both of the species preferred diverse habitats and were spread over the entire available space during the monsoon; they did not show any preference for the perch height during different seasons. Males had a positive correlation between body mass and preferred perch diameter. The present study suggests that several factors play an important role in habitat selection by these arboreal pit vipers, thus making them highly habitat-specific.

基于MAXENT模型的贺兰山岩羊生境适宜性评价

Habitat evaluation has an important significance for management of wildlife populations and conservation planning. Geographic Information Systems( GIS) and abundant landscape-level data provide new opportunities for biologists to evaluate wildlife habitat quality. Maximum Entropy( MAXENT) is a recently introduced modeling technique,achieving high predictive accuracy and enjoying several additional attractive properties. With the purpose of predicting habitat for blue sheep( Pseudois nayaur) in the Helan Mountain Range,we collected the occurrence records for this species and the environmental factors,the occurrence records were collected from the study area from 2010 to 2011,and the date of environmental factors were extracted from the Thematic Mapper( TM) image of Helan Mountain in 2007. The method relies on the combined use of GIS and Maximum Entropy( MAXENT) model in this research. GIS was used to produce the data needed in the model,MAXENT can model species geographic distributions with presence-only data,and is suitable for the research because absence data are not available for blue sheep. A map indicated the distribution of habitat suitability of blue sheep in Helan Mountain generated from the data and software. In this paper,the method of Receiver Operating Characteristic( ROC) curve analysis was used to assess the accuracy of MAXENT model,the area under ROC curve( AUC) of the model was 0. 915,indicating that the result of assessment was excellent,and the results showed the relationships between the distribution of blue sheep and the environmental factors,the result of Jackknife test indicated that the mining,slope,altitude and road were the main factors influencing habitat selection of blue sheep. Along with the increase of slope,distance from mine and road,the habitat suitability increased gradually,and habitat suitability decreased gradually with the increasing distance from water. Suitable habitat was mainly distributed in southwest of Ningxia Helan Mountain National Nature Reserve( east part) and lesser distributed in the Inner-Mongolia Helan Mountain National Nature Reserve( west part),with the total area of 1 006. 9km2,accounting for 28% of the total assessment area. Blue sheep preferred to use montane savanna dominated and the rugged slopes at elevations of 1 500—2 300 m. There were two factors interfered in achieving accurate results,one was difficult to reach occurrence points for the steep terrain,and the other was that we could not get the information of traffic flow on every road. During the research,we reduced the error by recording the nearest position to the target point and choosing the main road on the maps. The results showed that the most serious human interferences were mining and road,more regulatory actions are needed to be taken in those aspects to improve the habitat's quality as well as promote the progress of the population.

Habitat selection by hooded seals (Cystophora cristata) in the Northwest Atlantic Ocean

Abstract Andersen, J. M., Wiersma, Y. F., Stenson, G. B., Hammill, M. O., Rosing-Asvid, A., and Skern-Maurizen, M. 2013. Habitat selection by hooded seals (Cystophora cristata) in the Northwest Atlantic Ocean. – ICES Journal of Marine Science, 70:173–185. We examined annual habitat use for 65 hooded seals (32 adult females, 17 adult males, and 16 juveniles) equipped with satellite relay data loggers (SRDLs) in spring or summer during five field seasons (2004–2008). A combined approach using first passage time (FPT) analysis and a generalized additive model (GAM) was applied to test for habitat selection, with a focus on environmental parameters of depth, slope, ice, sea surface temperature (SST), and chlorophyll. The models were run on adult males, adult females, and juveniles separately, and the results identified SST, depth, and chlorophyll as the most important factors influencing habitat selection across all categories. Furthermore, males and females preferred similar habitat conditions, but were separated geographically, and by depth, at various times of the year. Males appeared to be more localized in their habitat use patterns, focusing their search effort in areas of complex seabed relief such as Baffin Bay, Davis Strait, and the Flemish cap, while females concentrated their search effort along shelf areas (e.g. the Labrador shelf). These findings support our hypothesis that hooded seals prefer areas where topography and oceanographic processes create favourable foraging conditions.

Spatial segregation of sympatric marten and fishers: the influence of landscapes and species‐scapes

Co‐occurring species are rarely considered as a factor influencing habitat selection. However, niche theory predicts that sharing resources, predators, and other interspecific interactions can limit the environmental conditions under which a species may exist. How does the spatial distribution of one species affect that of another within shared landscapes? We tested whether sympatric marten Martes americana and fishers M. pennanti in a mountain landscape in Alberta, Canada exhibit local‐scale spatial segregation, beyond differential habitat selection. We modelled marten and fisher distribution in relation to remotely‐sensed habitat data and species co‐occurrence, using generalized linear models and information‐theoretic model selection. Marten and fishers selected different habitat types and showed different responses to habitat fragmentation. Even after accounting for these differences, the absence of one species significantly explained the occurrence of the other. We conclude that the spatial distribution of marten and fishers influences habitat selection by each other at landscape scales, and hypothesize that this pattern may result from competition in a spatially heterogeneous environment. Species‐habitat models that consider only resources may fail to capture key predictors of species’ occurrence. Reliable prediction and inference requires that ecologists expand from landscapes to also include species‐scapes: a spatial plane of species interactions that combines with resources to drive species’ distributions.

Multi‐scale resource selection and spatial ecology of the Indian fox in a human‐dominated dry grassland ecosystem

Resource selection by animals is a scale-dependent hierarchical process of behavioural responses to environmental factors. Lack of information on such habitat selection dynamics can hamper the conservation management of species and habitats. For example, little is known about the space-use patterns of species in the semi-arid grasslands of peninsular India. The Indian fox Vulpes bengalensis, a poorly studied, yet reportedly widespread carnivore of the Indian subcontinent, represents an example of such lack of information. We determined the factors influencing habitat selection by Indian foxes at two levels in a multiple-use human-dominated landscape. Indian foxes are found in the highest densities in dry-grassland habitats, but are also reported to be opportunistic omnivores. Thus, we hypothesized that foxes select mainly for native grassland over human-modified habitats at a landscape level, but may not avoid human-modified habitats at the home-range level to take advantage of increased rodent availability in agricultural areas. We analysed radio-telemetry data from 32 Indian foxes using (1) a utilization distribution-weighted compositional analysis to determine the main components of home-range selection at the landscape level; (2) a discrete-choice analysis to determine the factors influencing the selection of habitat within the home ranges. At the landscape level, Indian foxes selected for native grasslands, forestry plantations and fallow land over human-dominated habitats such as agricultural land and human settlements. The presence of native grasslands was also the dominant predictor of habitat selection at the home-range scale across all seasons. Our results show that natural grasslands are the most important predictor of space use at multiple scales. This has important conservation implications as the threatened semi-arid short grasslands are poorly represented in India's protected area network. Although Indian foxes are not currently considered endangered, failure to conserve remaining native grassland habitats may threaten this species along with other grassland obligates.

Breeding Habitat Selection of Reeves's Pheasant (<I>Syrmaticus reevesii</I>) in Dongzhai National Nature Reserve, Henan Province, China

Reeves's Pheasant (Syrmaticus reevesii) is a threatened pheasant species endemic to China. The habitat use of territorial male birds was surveyed by the help of live decoys in a core area of Dongzhai National Nature Reserve. The breeding habitat selection of this pheasant was examined at two scales (115 m and 250 m scale, i.e. 4.15 hm(2 ) and 19.63 hm(2 ), respectively), including the characteristics at distance scale. Investigation was based on line transect, RS and GIS in Dongzhai National Natural Reserve from 2001 to 2003. Moreover, a range of habitat variables were compared between used and control points at each scale, and stepwise logistic regression was applied to select the key scale and the key habitat factors in relation to breeding habitat selection of this bird. Our results stated that the territorial males at Baiyun occurred mostly in mixed forests, followed by fir forests, pine forests, shrubs, and broadleaf forests. The area of conifer forests was the key factor influencing habitat selection of this bird in breeding period at the scales of 115 m and 250 m, and the proximity of farmland was important for habitat selection in breeding seasons. Furthermore, Reeves's Pheasants attached great importance to the scale of 115 m. When considering a range of habitat variables at all scales within a multivariate regression, the leading factors having effect on habitat selection in the breeding period were areas of conifer forests at 115 m scale and the distance to farmland. In addition, these above results suggested that strengthening the management of suitable habitat, and optimizing the habitat configuration are important in promoting conservation of this bird. However, it also highlighted the importance of initiating future researches on the conifer forests and their impact on the population of Reeves's Pheasants, which would be beneficial to promote the habitat conservation of this pheasant more effectively.

Stochasticity as an alternative to deterministic explanations for patterns of habitat use by birds

Stochasticity is rarely explicitly investigated as a determinant of patterns of habitat use, even though evidence of its influence would undermine support for deterministic models of habitat selection. To assess the role of stochasticity in generating patterns in habitat use, we compared observed patterns of year‐to‐year variation in habitat use of 20 bird species over five years with patterns randomly generated from null models with different biological constraints (i.e., abundance, territoriality, exclusion of unused habitat, site fidelity, and habitat preference). We were able to recreate patterns of variability in spatial distributions with one or more null models for 18 species, suggesting an important role of stochasticity. Although year‐to‐year variability could be modeled as a purely stochastic process for only four species, null models in which random variability was constrained by the influences of vegetation or site fidelity collectively matched the observed patterns of variability of all 18 species. Support for these two models suggested that factors that increase the likelihood of returning to a previously used area and thus limit the spatial extent of random territory placement can generate patterns similar to those we observed. Greater support for models with preference constraints (i.e., models that included bird–vegetation associations) over models with avoidance constraints (i.e., models that excluded areas that were never occupied) indicated that preference was the primary mode of habitat selection. Stochastic patterns in habitat use may have resulted from a weak relationship between habitat selection and habitat quality, influence of non‐vegetation habitat features (e.g., climatic fluctuations), nonequilibrium conditions, and a greater influence of stochastic variation at small spatial and temporal scales. Alternatively, responses to environmental cues may have been deterministic, but in summation, these responses may have created variability in spatial distribution patterns that was indistinguishable from random variation. In such cases, we suggest that it may be easier to model variation in habitat use as a random process rather than using deterministic models that account for a multitude of environmental factors influencing habitat selection of birds. Regardless, stochasticity may play a larger role in generating patterns of habitat use than is often considered, and it deserves wider attention.