Considering behavioral state when predicting habitat use: Behavior-specific spatial models for the endangered Tasmanian wedge-tailed eagle

Context Animals’ use of space and habitat selection emerges from their movement patterns, which are, in turn, determined by their behavioural or physiological states and extrinsic factors. Aim The aims of the present study were to investigate animal movement and incorporate the movement patterns into habitat selection analyses using Global Positioning System (GPS) location data from 16 black bears (Ursus americanus) in a fragmented area of Florida, USA. Methods Hidden Markov models (HMMs) were used to discern the movement patterns of the bears. These results were then used in step-selection functions (SSFs) to evaluate habitat selection patterns and the factors influencing these patterns. Key results HMMs revealed that black bear movement patterns are best described by three behavioural states: (1) resting (very short step-lengths and large turning angles); (2) encamped (moderate step-lengths and large turning angles); and (3) exploratory (long step-lengths and small turning angles). Bears selected for forested wetlands and marsh wetlands more than any other land cover type, and generally avoided urban areas in all seasons and when in encamped and exploratory behavioural states. Bears also chose to move to locations farther away from major roads. Conclusions Because habitat selection is influenced by how animals move within landscapes, it is essential to consider animals’ movement patterns when making inferences about habitat selection. The present study achieves this goal by using HMMs to first discern black bear movement patterns and associated parameters, and by using these results in SSFs to investigate habitat selection patterns. Thus, the methodological framework developed in this study effectively incorporates state-specific movement patterns while making inferences regarding habitat selection. The unified methodological approach employed here will contribute to an improved understanding of animal ecology as well as informed management decisions. Implications Conservation plans focused on preserving forested wetlands would benefit bears by not only providing habitat for resting and foraging, but also by providing connectivity through fragmented landscapes. Additionally, the framework could be applied to species that follow annual cycles and may provide a tool for investigating how animals are using dispersal corridors.

Understanding habitat selection of top predators is critical to predict their impacts on ecological communities and interactions with humans, particularly in recovering populations. We analyzed habitat selection in a recovering population of bobcats (Lynx rufus) in south-central Indiana using a Random Forest model. We predicted that bobcats would select forest habitat and forest edges but avoid agriculture to maximize encounters with prey species. We also predicted that bobcats would avoid developed areas and roads to minimize potential antagonistic interactions with humans. Results partially supported our predictions and were consistent with bobcats in the early stages of population expansion. Bobcats exhibited elevated use near forest edges, thresholds of avoidance near agriculture, and thresholds of selection for low and intermediate habitat heterogeneity. Bobcats exhibited peak probability of use 1–3 km from major roads, >800 m from minor roads, and <1km from developed areas, suggesting tradeoffs in reward for high-quality hunting areas and mortality risk. Our Random Forest model highlighted complex non-linear patterns and revealed that most shifts in habitat use occurred within 1 km of the edge of each habitat type. These results largely supported previous studies in the Midwest and across North America but also produced refinements of bobcat habitat use in our system, particularly at habitat boundaries. Refined models of habitat selection by carnivores enable improved prediction of the most suitable habitat for recovering populations and provides useful information for conservation.

Recently, several wild or semi-wild herds of European bison have been reintroduced across Europe. It is essential for future successful bison reintroductions to know how the European bison use different habitats, which environmental parameters drive their habitat selection, and whether their habitat use and behavioural patterns in new reintroduction sites differ from habitats where European bison have been roaming freely for a long time. Here, we address these questions for a 40-ha enclosed site that has been inhabited by semi-free ranging European bison since 2012. The site, Vorup Meadows, is adjacent to the Gudenå river in Denmark and consists of human-modified riparian meadows. During 2013 we monitored the behavioural pattern and spatial use of the 11 bison present and in parallel carried out floristic analyses to assess habitat structure and food quality in the enclosure. We tested habitat use and selection against environmental parameters such as habitat characteristics, plant community traits, topography, and management area (release area vs. meadow area) using linear regression and spatial models. The bison herd had comparable diurnal activity patterns as observed in previous studies on free-roaming bison herds. Topography emerged as the main predictor of the frequency of occurrence in our spatial models, with high-lying drier areas being used more. Bison did not prefer open areas over areas with tree cover when accounting for habitat availability. However, they spent significantly more time in the release area, a former agricultural field with supplementary fodder, than expected from availability compared to the rest of the enclosure, a meadow with tree patches. We wish to increase awareness of possible long-term ethological effects of the release site and the management protocols accomplished here that might reduce the ecological impact by the bison in the target habitat, and thereby compromise or even oppose the conservation goals of the conservation efforts.

Habitat selection analysis provides useful information on how animals become distributed in response to spatial heterogeneity. Here, we analyze the habitat use and selection of different water bodies (marsh, swamps and round shallow lakes) by capybaras ( Hydrochoerus hydrochaeris ) and their relation to environmental variables during contrasting climate‐hydrological seasons in the Esteros del Iberá (Corrientes, Argentina). We evaluated the intensity of use by capybaras through the total number of individuals (abundance) in each water body, the number and mean size of social groups, and the physical and vegetation characteristics of the environment. The capybaras used marsh and swamps according to availability in both seasons, while they used rounded shallow lakes less than their available would suggest in summer. The use intensity of different rounded shallow lakes estimated based on group size did not show significant differences. In contrast, significant differences were observed when evaluated by the number of individuals in each rounded shallow lake. Different intensity of use was closely associated with environmental and vegetation characteristics. The results show that habitat suitability for capybaras is associated with vegetation cover and “embalsados” in the low‐lying area rather than with the morphometry of the rounded shallow lakes. The pattern of habitat selection may depend on forage quality, water availability for thermoregulation and mating, and presence of shelter and resting sites. On the other hand, the present study shows how the size, shape and the abundance of different types of water bodies affect population abundance and density.

For arboreal lizards, the ability to cling or adhere to the substrate is critical for locomotion during prey capture, predator escape, thermoregulation and social interactions. Thus, selection on traits related to clinging is likely strong. Correlations between morphology, performance and habitat use have been documented in arboreal lizards, providing a framework for using functional traits to predict habitat use in the field. We tested the hypothesis that clinging performance predicts habitat use in an actively assembling community of introduced lizards in Hawaiʻi comprised of anoles (Anolis carolinensis, A. sagrei) and day geckos (Phelsuma laticauda). We measured morphological traits (toepad area and lamellae number) and tested clinging performance on two artificial and eight natural substrates in the laboratory. We measured habitat use in 10 m × 10 m outdoor enclosures where habitat availability was controlled and the lizard species assemblage was manipulated to reflect all species combinations. The enclosure experiment generated more than 9,000 habitat use observations from 360 lizards. Morphological traits that predict performance in Anolis were not predictive in Phelsuma, indicating that direct measures of performance are necessary for comparisons between the genera. Measuring clinging performance on multiple substrates provided key insights into patterns of habitat use. While all three species performed best on an artificial smooth substrate (acrylic), performance on natural substrates predicted which texture (rough vs. smooth) was most often used by each species. Performance predicted perch height use: species with the greatest clinging performance (A. carolinensis and P. laticauda) across substrates perched twice as high as A. sagrei. We did not observe habitat shifts in the height or texture of perches used by any species in response to experimental manipulation of the lizard species assemblage. Our results highlight the inextricable link between ecology, morphology and performance, the importance of measuring functional traits in ecologically relevant ways, and the potential for resource partitioning to be influenced by differences in the ability to attach to different substrates.

For several fish species, increased river discharge has been linked to behavioral changes, including movement towards particular habitats. From 2000 to 2003, we used radiotelemetry to monitor habitat use by 42 muskellunge Esox masquinongy within a 17‐km reach of the New River, Virginia; to evaluate habitat selection; and to determine whether habitat use and selection were affected by discharge. Water depth, occurrence of aquatic vegetation, substrate type, and distance to riverbanks within the study reach were mapped with hydroacoustic and Global Positioning System technologies. Real‐time discharge measurements from an upstream U.S. Geological Survey stream gauge were used to classify fish locations into those made during periods of reduced (&lt;75 m3/s) or increased (&gt;75 m3/s) discharge. Seasonal habitat selection models for the different discharge levels were created using logistic regression. Differences in logistic regression coefficients between models were tested with multivariate chi‐square tests and Bonferroni‐corrected pairwise comparisons. Meta‐analytic averaging of Pearson's correlation coefficients was used to determine the overall effect size of discharge on habitat use by muskellunge. Overall, muskellunge exhibited a positive selection for deeper habitats; however, discharge was found to significantly affect both habitat use and selection. Habitat use was consistent with the hypothesis that fish moved to shallower habitats (both summer and winter) located closer to riverbanks (winter only) during periods of increased discharge. In terms of habitat selection, selection strengths for variables such as water depth (summer and winter) and distance to shoreline (winter only) generally weakened during periods of increased discharge, indicating that habitat use became more proportionate to availability. Increased movement as a result of increased discharge has been theorized to potentially reduce winter survival of fish because of seasonal energetic limitations. Thus, indirect effects on fish from dam operating modes (e.g., hydropeaking) may be as important as direct effects when evaluating biotic implications of water release schedules.

BackgroundThere is strong incentive to model behaviour-dependent habitat selection, as this can help delineate critical habitats for important life processes and reduce bias in model parameters. For this purpose, a two-stage modelling approach is often taken: (i) classify behaviours with a hidden Markov model (HMM), and (ii) fit a step selection function (SSF) to each subset of data. However, this approach does not properly account for the uncertainty in behavioural classification, nor does it allow states to depend on habitat selection. An alternative approach is to estimate both state switching and habitat selection in a single, integrated model called an HMM-SSF.MethodsWe build on this recent methodological work to make the HMM-SSF approach more efficient and general. We focus on writing the model as an HMM where the observation process is defined by an SSF, such that well-known inferential methods for HMMs can be used directly for parameter estimation and state classification. We extend the model to include covariates on the HMM transition probabilities, allowing for inferences into the temporal and individual-specific drivers of state switching. We demonstrate the method through an illustrative example of plains zebra (Equus quagga), including state estimation, and simulations to estimate a utilisation distribution.ResultsIn the zebra analysis, we identified two behavioural states, with clearly distinct patterns of movement and habitat selection (“encamped” and “exploratory”). In particular, although the zebra tended to prefer areas higher in grassland across both behavioural states, this selection was much stronger in the fast, directed exploratory state. We also found a clear diel cycle in behaviour, which indicated that zebras were more likely to be exploring in the morning and encamped in the evening.ConclusionsThis method can be used to analyse behaviour-specific habitat selection in a wide range of species and systems. A large suite of statistical extensions and tools developed for HMMs and SSFs can be applied directly to this integrated model, making it a very versatile framework to jointly learn about animal behaviour, habitat selection, and space use.

Transformed landscapes caused by human activity leave remnant patches of natural habitat for wildlife. The persistence of species in the face of such transformation depends on individuals’ ability to adapt to novel habitat, and to secure resources and reproductive opportunities despite habitat alterations. The leopard, Panthera pardus, is the last free-roaming top carnivore in South Africa whose high trophic status and wide-ranging movements make them an effective focal species in conservation planning. Using location data from leopards, we investigated key correlates of habitat selection in human-altered landscapes at two spatial scales. We compared sex-related differences and predicted how conspecific home range locations influenced habitat selection. Leopards avoided human-altered landscapes more strongly at the large spatial scale, where both sexes selected core areas near formally protected areas. Conspecific home range locations had a strong positive effect at both spatial scales for males, while for females, conspecifics explained fine-scale habitat selection by selecting areas near neighboring females. Spatial scale, sex-related differences, and conspecific location play roles in habitat selection for solitary felids and have implications for conservation planning and management. Excluding these factors may result in inappropriate species management policies.

The exponential growth of human population and infrastructure is significantly reducing the amount of ecological resources available for wild animals. We analyzed the effect of human activity on Barbary macaques Macaca sylvanus, an endangered species restricted to the fragmented forests of Morocco and Algeria, using location data from five social groups inhabiting Ifrane National Park, Morocco. We used a resource selection function to explore the effects of anthropogenic disturbance on macaque habitat selection, using nine natural, social, and anthropogenic disturbance variables as predictors. Forest cover, home range overlap, herding route proximity, and road proximity were all significant predictors of habitat use. Macaques avoided areas used by local shepherds, to reduce the risk of attack by shepherds’ dogs, but approached roads to increase the chances of provisioning by tourists. However, herding route and road use varied seasonally in line with levels of human use, suggesting that macaques may be navigating their environment strategically (in space and time) to balance food acquisition and risk avoidance. The results of this study highlight the importance of assessing human impact on habitat selection in both space and time. Our data on seasonal variations in macaques’ use of roads can help prevent road injuries, a major source of mortality for provisioned macaques, by focusing management efforts by national park workers in time and space. Furthermore, understanding when and where macaques seek provisioning from tourists can help combat provisioning, which negatively impacts macaque health, behavior, and susceptibility to poaching.

Incorporating uncertainty into analyses of red-crested pochard habitat selection

Whale sharks (Rhincodon typus) are found circumglobally in tropical, subtropical, and warm temperate waters, and their known seasonal aggregations and migratory movements are influenced by factors such as ocean currents, thermobiological systems, and patterns of productivity. Several locations in the eastern tropical Pacific Ocean are known habitats for R. typus; Although it has long been known that whale sharks aggregate along the Panama coast, little is known in relation to their movement patterns, behavior, and habitat use. In this study, we investigated the movements and behaviors of R. typus tagged in Panama in relation to oceanographic variables and examined the overlap of foraging habitat and migratory routes with marine protected areas (MPAs), industrial fishing areas, and marine traffic. Satellite tracks from 30 R. typus tagged in the coastal waters of Panama were examined, including nine tags suspicious of earlier detachment. A hidden Markov model was then used to identify different behavioral states (foraging and migrating) and their relationships with environmental variables (sea surface temperature, primary productivity, chlorophyll-a concentrations, and eddy location/speed) Tracks were also superimposed on maps of MPAs, industrial fishing areas, and regional marine vessel traffic to identify the degree of overlap. Rhincodon typus foraged mainly within the Panamanian exclusive economic zone but also moved north and south along the coast and out to the open ocean. Significant differences in environmental conditions were found between sites in which foraging and migrating behaviors were recorded. Higher productivity and chlorophyl concentration were associated with foraging behavior, while higher eddy speeds were observed when sharks migrated. Rhincodon typus used MPAs; however, there was a high degree of overlap between their habitat and areas of industrial fishing and marine vessel traffic. Our results highlight the use of the coastal waters of Panama, oceanic seamounts, and ridges, MPAs and industrial fishing areas by R. typus for foraging and migration. Additionally, our findings highlight the importance of satellite tracking studies for understanding the behavior and habitat use of highly mobile migratory species, such as R. typus.

Knowledge and understanding of bat habitat associations and the responses of bats to forest management are critical for effective bat conservation and management. Few studies have been conducted on bat habitat use in the southeast, despite the high number of endangered and sensitive species in the region. Our objective was to identify important local, stand, and landscape factors influencing bat habitat use in northwestern South Carolina, USA. We hypothesized that use would be greatest 1) at points with relatively sparse vegetation, 2) in early successional and mature stands, and 3) at points close to streams. We also predicted that species would exhibit different patterns of habitat use based on morphology. We placed Anabat II bat detectors at points located in 3 forest types and 3 age classes to record bats from May–August 2004 and 2005. We used an information theoretic approach to determine the variables that best predicted use by bats. Vegetation density at the sample point was the best predictor of overall bat presence in 2004. In 2005 vegetation density and distance to the closest road were the best predictors of overall bat use; the model containing age class also had good support. Bats were more likely to be recorded at points with sparse vegetation, farther from roads, and in early successional stands. Vegetation density was also the best predictor of habitat use by big brown bats (Eptesicus fuscus) and red bats (Lasiurus borealis); both species were far more likely to be recorded at points with sparse vegetation at the sample point. Eastern pipistrelles (Pipistrellus subflavus) were also more likely to be recorded at points with sparse vegetation and in early successional stands. The best predictors of northern long-eared bat (Myotis septentrionalis) habitat use were vegetation density and age class. Northern long-eared bats were more likely to be recorded at points with sparse vegetation and in mature stands. Our results suggest that early successional habitats and small openings and gaps within forest stands provide suitable commuting and foraging bat habitat in northwestern South Carolina. However, mature forests are also important for some species. Forest management practices that provide a variety of age classes across the landscape and that create gaps and openings within mid- and late-successional stands will likely provide suitable habitat for bats in the mountains of South Carolina.

Large animals have longer flight distances when approached by a potential predator than small animals, and predators therefore have longer flight distances than their prey. The ubiquitous presence of humans in urban areas selects for differential invasion by animals with short flight distances, and adaptation to urban environments results in further reductions in flight distance. Because prey are better able to cope with the proximity of humans than predators due to differences in flight distance, urban areas may act as refuges. Predators on average have a flight distance that is 8 times larger than that of their prey. In urban areas, humans were present within a distance of 54 m (the mean flight distance of raptor species) 16% of the time and 4% of the time within a distance of 7 m (the mean flight distance of prey species). In contrast, humans were present 1.2% of the time within a distance of 54 m but only 0.1% of the time within a distance of 7 m in rural habitats. Therefore, prey gained a 10-fold increase in predator refuge in urban compared with rural habitats. The reduction in flight distance between the ancestral rural and the current urban habitats decreased with the difference in flight distance between raptors and that of prey. The difference in flight distance between predators and that of prey increased with increasing preference of prey by sparrowhawks Accipiter nisus relative to their abundance, providing evidence of a selective advantage for prey. These results suggest that birds that are prey of raptors enjoy a selective advantage from association with humans.

ABSTRACTSensitivity of bats to land use change depends on their foraging ecology, which varies among species based on ecomorphological traits. Additionally, because prey availability, vegetative clutter, and temperature change throughout the year, some species may display seasonal shifts in their nocturnal habitat use. In the Coastal Plain of South Carolina, USA, the northern long‐eared bat (Myotis septentrionalis), southeastern myotis (Myotis austroriparius), tri‐colored bat (Perimyotis subflavus), and northern yellow bat (Lasiurus intermedius) are species of conservation concern that are threatened by habitat loss. Our objective was to identify characteristics of habitat used by these species during their nightly active period and compare use between summer and winter. We conducted acoustic surveys at 125 sites during May–August and at 121 of the same 125 sites December–March 2018 and 2019 in upland forests, bottomland forests, fields, ponds, and salt marsh and used occupancy models to assess habitat use. The northern long‐eared bat and southeastern myotis (i.e., myotis bats) used sites that were closer to hardwood stands, pine stands, and fresh water year‐round. We did not identify any strong predictors of tri‐colored bat habitat use in summer, but during winter they used bottomland forests, fields, and ponds more than salt marsh and upland forests. During summer and winter, northern yellow bats used sites close to fresh water and salt marsh. Additionally, during summer they used fields, ponds, and salt marsh more than upland and bottomland forests, but in winter they used bottomland forests, fields, and ponds more than upland forest and salt marsh. Our results highlight important land cover types for bats in this area (e.g., bottomland forests, ponds, and salt marsh), and that habitat use changes between seasons. Accounting for and understanding how habitat use changes throughout the year will inform managers about how critical habitat features may vary in their importance to bats throughout the year. © 2021 The Wildlife Society.

A primary means of conserving a species or a habitat in a human‐dominated landscape is through promoting coexistence with humans while minimizing conflict. For this, we should understand how wildlife is impacted by direct and indirect human activities. Such information is rare in areas with high human densities. To investigate how animals respond to altered ecological conditions in human‐dominated landscapes, we focused on a wild herbivore of conservation concern in the Krishnasaar Conservation Area (KrCA) in Nepal. Here, blackbuck Antilope cervicapra, a generalist grazer, lives in refugia located with a growing human population. We studied the impacts of humans on habitat use and behavior of blackbuck. We laid 250 × 250 m grid cells in the entire KrCA and carried out indirect sign surveys with three replications for habitat use assessment. We observed herds of blackbuck for 89 h in different habitat types using scan sampling methods. Our habitat‐use survey showed that habitats under intensive human use were hardly used by blackbuck, even when high‐quality forage was available. Habitat openness was the major predictor of habitat use inside the core area, where levels of human activities were low. We also found a positive correlation between habitat use by blackbuck and livestock. Blackbuck were substantially more vigilant when they were in forest than in grassland, again indicating an influence of risk. Overall, blackbuck appear to be sensitive to the risk associated with both natural and anthropogenic factors. Our findings have direct implications for managing human–wildlife interactions in this landscape, specifically regarding strategies for livestock grazing in habitats highly used by blackbuck and concerning predictions of how changing land use will impact the long‐term persistence of blackbuck. Our work suggests that wild herbivores may be able to persist in landscapes with high human densities so long as there are refuges where human activities are relatively low.