Impact of habitat fragmentation on activity and hunting behavior in the tawny owl, Strix aluco

I examined the effect of woodland fragmentation on activityand hunting behavior in the tawny owl. I made three predictionson the effect of fragmentation, two of which were upheld andone rejected. Over 2 years, 24 owls were radio tracked in thenonbreeding season. Eight of these were in continuous woodlandand the rest in highly fragmented woodland. For each owl, Irecorded data on small mammal availability, diet, home rangesize, perch time, and interperch distance. In accordance withthe first two predictions, owls in fragmented woodlands hadlonger interperch distances and perch times, but contrary tothe third prediction, perch times were positively correlatedwith small mammal density. This was thought to be due to owlsaltering their hunting to other prey types when small mammalswere scarce. Within fragmented woodlands, perch times were thesame between the sexes, but males had slightly greater interperchdistances than females. Male owls in fragmented woods flew 40%further per hour than males in continuous woodland. For datathroughout the night, food availability and area of trees inhome range accounted for 65% of the variation in perch times.For data before 2200 h, area of trees alone accounted for thesame amount of variation. The data suggest that habitat fragmentation,particularly through reducing woodland area, can greatly influenceowl activity and hunting behavior.     

Home range size scales to habitat amount and increasing fragmentation in a mobile woodland specialist

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Home range and habitat selection of spotted owls in the central Sierra Nevada

We studied home range and habitat selection of radio-marked adult California spotted owls (Strix occidentalis occidentalis) randomly selected from among the breeding population of owls in the central Sierra Nevada, California from June to October 2006. The most parsimonious home-range estimate for our data was 555 ha (SE = 100 ha). Home-range size was positively correlated with the number of vegetation patches in the home range (habitat heterogeneity). We used resource selection ratios to examine selection of vegetation types by owls within our study area. Owl home ranges contained a high proportion of mature conifer forest, relative to its availability, although the confidence interval for this estimate overlapped one. We also used resource selection functions (RSF) to examine owl foraging habitat selection. Relative probability of selection of foraging habitat was correlated with vegetation classes, patch size, and their interaction. Owls showed highest selection rates for large patches (>10 ha) of pole-sized coniferous forest. Our results suggested that spotted owls in the central Sierra Nevada used habitat that contained a high proportion of mature conifer forest at the home-range scale, but at a finer scale (foraging site selection) owls used other vegetation classes interspersed among mature forest patches, consistent with our hypothesis that spotted owls may use other forest types besides old growth and mature forests when foraging. Our study provides an unbiased estimate of habitat use by spotted owls in the central Sierra Nevada. Our results suggest that forest managers continue to protect remaining mature and old-growth forests in the central Sierra Nevada because owl home ranges contain high proportions of these habitats. However, our results also showed that owls used younger stands as foraging habitat so that landscape heterogeneity, with respect to cover types, may be an important consideration for management but we did not attempt to relate our findings to fitness of owls. Thus management for some level of landscape heterogeneity for the benefit of owls should proceed with caution or under an adaptive management framework. © 2011 The Wildlife Society.     

Sexual segregation in winter, spring dispersal and habitat use in the pheasant (Phasianus colchicus)

Sexual segregation, spring dispersal and late winter to spring habitat selection were studied in the pheasant Phasianus colchicus L. on two areas for which the proportions of different habitats were similar. On one of the sites (Damerham) hand-reared pheasants were released for shooting. On the other (Fulwell) no releasing or shooting took place.
The sex ratio of birds feeding in fields in autumn favoured males because females fed in groups within woods. Groups of birds were significantly segregated by sex during early to late winter periods, but by late March they were not. Male groups and solitary males in winter were more evenly dispersed than female groups.
At Fulwell, female winter groups consisted of regular group members (mainly adults) and transitory individuals called 'drifters' (mainly immatures).
Females in their first breeding attempt dispersed further from their winter range to their breeding range than did adult females and females dispersed further than males. Males gaining a territory for the first time moved significantly further than old territory owners. Territorial males moved less than non-territorial males between successive spring ranges.
During March June, habitat use by 33 radio-tagged females changed markedly from mixed and deciduous woodland to fields sown with winter and spring corn. The implications for management are outlined.     

Use of space and habitat selection by roe deer Capreolus capreolus in a Mediterranean coastal area: how does woods landscape affect home range?

The home-range dynamics and habitat selection of nine roe deer were studied from March 1994 to August 1994 in the Maremma Natural Park along the Tyrrhenian coast of Italy. The habitat was highly fragmented, with open agricultural fields prevailing in the study area (57%); the climate was Mediterranean. Data on spatial behaviour were collected by radio-tracking techniques. Habitat selection and structure were investigated by compositional and landscape analysis, both within the study area and within the home ranges. Animals of our sample showed spatial-use patterns varying from stationary to roaming. Stationary individuals used small home ranges while roaming ones moved, especially during the reproductive period in July and August. The percentage and structure of woodlands influenced the size of home ranges and the behaviour of males: stationary males used large amounts of woodlands within their home ranges and showed a territorial behaviour whereas males that used a high percentage of fields showed wider home ranges even during the territorial period. Females seemed to be less influenced by the presence and patch-structure of woodland within their home range. Landscape structure and habitat composition seemed to be important factors influencing the spatial behaviour of this roe deer population.     

Habitat selection of European pine marten in Central Italy: from a tree dependent to a generalist species

Studies at small spatial scale are often fundamental to highlight the behavioural plasticity of a species and thus have important implications for conservation planning, in particular for species usually considered as habitat specialists. We investigated second-order habitat selection of the European pine marten in an area dominated by deciduous oak forest and open fields in central Italy, by radio-tracking 16 pine martens (eight males, eight females). Pine martens placed home ranges in areas with more open field than in the study area, whereas woodland (oak and conifer forests) comprised a smaller portion of the home range than predominant forest character of the studied area. Although the presence of the species in the open habitats has been documented, to our knowledge, our results provide the first evidence of home range establishment in this cover type by pine marten at population level. The combination of low predation risk and high availability of resources could allow pine martens to occupy open fields in our study area. We highlighted different individual strategies of habitat selection, with some individuals placing home ranges in areas with high forest coverage while others occupying open areas. We found no effects of sex and body condition on habitat selection, and this could indicate that in the study area, both forested and non-forested cover types, such as open fields, shrub and anthropic areas, can provide adequate food, overhead cover and resting sites for all individuals. Pine marten ability to occupy open fields seems thus more related to the behavioural flexibility of the species, rather than to the need to supplement dens and forage from complementary lower quality habitat. The high quality of the Mediterranean continental area studied could also explain the selection of open areas by the pine marten. Our results offer useful information on pine marten ecology and may be helpful for conservation management of this species in southern Europe.     

Scale dependency and functional response in moose habitat selection

Habitat selection can be influenced by the distribution of the habitat types in the landscape as well as net gain in visiting patches of resources, causing individual variation in habitat selection. Moreover, the hypothesis of functional response in habitat selection predicts that the degree of selection of a resource depends on its relative availability. We used radio-telemetry data from individual moose on an island off the coast of northern Norway to evaluate whether the selection of habitat types at the landscape scale differed from the choice of habitat types within the home range, and investigated the functional response in habitat selection by relating individual habitat selection to home range characteristics. At the landscape scale, moose selected for habitat types that provided both good forage and cover, with small differences between sex and age groups. At the home range scale, all individuals selected habitat types that were associated with cover and low human impact. Habitat selection was not modified by local moose density, but was related to home range size at both spatial scales. Larger home ranges contained larger proportions of non-preferred habitat types compared to smaller home ranges. At the home range scale, the selection for a habitat type decreased with its relative availability, indicating a functional response in habitat selection. This suggests that habitat selection is modified by home range size, which influences the availability of habitat types and shapes individual habitat selection patterns. Our results support previous suggestions that analyses of habitat or resource selection should follow a multi-scale approach. Both the relative availability of habitat types as well as individual variation in home range size should be accounted for in order to disentangle the complex mechanisms that contribute to shape patterns of resource selection in animals.     

Home range dynamics,habitat selection,and survival of Greater Roadrunners

ABSTRACT Greater Roadrunners (Geococcyx californianus) are common, poorly studied birds of arid and semi‐arid ecosystems in the southwestern United States. Conservation of this avian predator requires a detailed understanding of their movements and spatial requirements that is currently lacking. From 2006 to 2009, we quantified home‐range and core area sizes and overlap, habitat selection, and survival of roadrunners (N= 14 males and 20 females) in north‐central Texas using radio‐telemetry and fixed kernel estimators. Median home‐range and core‐area sizes were 90.4 ha and 19.2 ha for males and 80.1 ha and 16.7 ha for females, respectively. The size of home range and core areas did not differ significantly by either sex or season. Our home range estimates were twice as large (x?= 108.9 ha) as earlier published estimates based on visual observations (x?= 28–50 ha). Mean percent overlap was 38.4% for home ranges and 13.7% for core areas. Male roadrunners preferred mesquite woodland and mesquite savanna cover types, and avoided the grass‐forb cover type. Female roadrunners preferred mesquite savanna and riparian woodland cover types, and avoided grass‐forb habitat. Kaplan‐Meier annual survival probabilities for females (0.452 ± 0.118[SE]) were twice that estimated for males (0.210 ± 0.108), but this difference was not significant. Mortality rates of male roadrunners were higher than those of females during the spring when males call from elevated perches, court females, and chase competing males. Current land use practices that target woody‐shrub removal to enhance livestock forage production could be detrimental to roadrunner populations by reducing availability of mesquite woodland and mesquite savanna habitat required for nesting and roosting and increasing the amount of grass‐forb habitat that roadrunners avoid.     

High interindividual variability in habitat selection and functional habitat relationships in European nightjars over a period of habitat change

An animal's choice of foraging habitat reflects its response to environmental cues and is likely to vary among individuals in a population. Analyzing the magnitude of individual habitat selection can indicate how resilient populations may be to anthropogenic habitat change, where individually varying, broadly generalist populations have the potential to adjust their behavior. We collected GPS point data from 39 European nightjars (Caprimulgus europaeus) at a UK breeding site where restoration measures have altered large areas of habitat between breeding seasons. We calculated individual habitat selection over four breeding seasons to observe changes that might align with change in habitat. We also analyzed change in home range size in line with change in habitat availability, to examine functional relationships that can represent trade‐offs made by the birds related to performance of the habitat. Individual explained more of the variation in population habitat selection than year for most habitat types. Individuals differed in the magnitude of their selection for different habitat types, which created a generalist population composed of both generalist and specialist individuals. Selection also changed over time but only significantly for scrub habitat (60% decrease in selection over 4 years). Across the population, individual home range size was 2% smaller where availability of cleared habitat within the home range was greater, but size increased by 2% where the amount of open water was higher, indicating the presence of trade‐offs related to habitat availability. These results highlight that using individual resource selection and specialization measures, in conjunction with functional responses to change, can lead to better understanding of the needs of a population. Pooling specialist and generalist individuals for analysis could hide divergent responses to change and consequently obscure information that could be important in developing effective conservation strategies.     

Patterns and strategies of winter habitat selection in alpine capercaillie

Based on radio telemetry, habitat distribution of 32 individual capercaillie Tetrao urogallus was compared with habitat availability at various levels of scale At forest stand level, capercaillie preferred large patches of late succession stages, and selected for moderate canopy closure and high abundance of feeding trees Hens and cocks selected home ranges with high proportions of old forest, and range size was related to old forest fragmentation Winter survival was high independently of habitat selection In cocks, habitat use was affected by social spacing, home range size and use of old forest were age-dependent, and habitat composition of winter ranges indirectly related to survival and mating success in spring Topography influenced habitat selection, as the birds preferred gentle slopes At the landscape scale, the distribution of bilberry Vaccinium myrtillus was the key to capercaillie habitat use, indicating that habitat requirements in autumn and spring influenced selection of winter ranges The study confirms that capercaillie in central Europe select habitats according to structural features typical of the boreal forests of the species' main distribution range However, spatio-temporal variation in resource abundance at the landscape scale sets significant limits to suitability of alpine capercaillie habitats     

Sika deer distribution and habitat selection: the influence of the availability and distribution of food, cover, and threats

Large populations of sika deer occur in lowland heath, woodland, and grassland mosaics in southern England. Previous studies have focused on understanding single factors potentially affecting distribution and habitat selection of sika deer rather than considering simultaneously effects of landscape configuration and human disturbance on their distribution and habitat selection. This study measured effects of habitat availability, landscape structure, and human disturbance on where sika deer placed their home ranges and habitat selection within those ranges. Two main hypotheses were tested: (1) habitat selection differs according to landscape structure and habitat availability at both landscape and home range scales and (2) distribution of sources of human disturbance within the home range of deer affects their distribution. Results from radiotracking 31 females provided support for the first hypothesis and partial support for the second. Habitat selection at the landscape and home range scales differed between landscapes with different habitat structure and availability and was driven by distribution and availability of food and cover and a perceived risk linked to disturbance. Furthermore, deer selected open areas close to cover and this selection was stronger with presence of human disturbance, although results differed between study areas with different habitat distribution and level of disturbance. The study highlights the importance for managing deer of a balance between grazing and cover resources and the distribution of human disturbance.     

Hierarchical habitat selection by barren-ground grizzly bears in the central Canadian Arctic

Using resource selection functions, we examined habitat selection patterns of barren-ground grizzly bears (Ursus arctos) in the central Canadian Arctic among and within home ranges. There was no difference between the sexes with regard to habitat selection patterns at the home range level (Wilks' 5, approx. F_11,11=1.27, P=0.37). Bear home ranges contain more esker habitat, tussock/hummock successional tundra, lichen veneer, birch seep, and tall shrub riparian areas relative to the proportional availability of habitats in the study area. We observed differences in habitat selection within home ranges among levels of sex/reproductive status (Wilks' 5, approx. F_20,412=3.32, P<0.001) and by season (Wilks' 5, approx. F_30,605=2.71, P<0.001). Eskers and tall shrub riparian zones were the habitats most preferred by bears throughout the year. Tussock/hummock successional tundra was also favored by males at varying times during the year and lichen veneers were favored in spring and autumn by most bears. Females with cubs tended to avoid the highest ranked habitat for males throughout the year. This pattern of habitat selection was not observed for females without accompanying young. Results of this study underline the importance of scale dependence in habitat selection. Failure to view habitat selection as a hierarchical process may result in a narrow and possibly misleading notion of habitat selection patterns.     

Predictive models of habitat preferences for the Eurasian eagle owl Bubo bubo: a multiscale approach

Habitat preference of eagle owls Bubo bubo were examined through comparing habitat composition around 51 occupied cliffs and 36 non-occupied cliffs in Alicante (E Spain). We employed Generalized Linear Models to examine patterns of habitat preference at three different spatial scales: nest site (7 km²), home range (25 km²), and landscape (100 km²). At the nest site scale, occupied cliffs were more rugged, had a greater proportion of forest surface in the surroundings, and were further from the nearest paved road than unoccupied cliffs. Additionally, probability of having an occupied cliff increased when there was another occupied territory in the surroundings. At both the home range scale and the landscape scale, high probabilities of presence of eagle owls were related to high percentages of Mediterranean scrubland around the cliffs, which are the preferred habitat of European rabbits Oryctolagus cuniculus , the main prey of the owls. We suggest a hierarchical process of habitat selection in the eagle owl concerning suitable trophic resources at the broadest scales and adequate sites for breeding and roosting at the smallest scale. However, it should be noted that some structural features such as the proximity of roads were not necessarily avoided by the owls, but their presence were possibly constrained by systematic killing of individuals. Our paper provides new evidence for the requirement of multi-scale approaches to gain insight into both the different limiting factors for the persistence of populations and the role of individual perception of the environment in the evolution of habitat selection.     

Time and travelling costs during chick‐rearing in relation to habitat quality in Little Owls Athene noctua

In many bird species, parents adjust their home‐ranges during chick‐rearing to the availability and distribution of food resources, balancing the benefits of energy intake against the costs of travelling. Over recent decades, European agricultural landscapes have changed radically, resulting in the degradation of habitats and reductions in food resources for farmland birds. Lower foraging success and longer foraging trip distances that result from these changes are often assumed to reduce the reproductive performance of parents, although the mechanisms are not well understood. We tested the behavioural response of chick‐rearing Little Owls Athene noctua to variation in habitat diversity in an agricultural landscape. We equipped females with GPS loggers and received adequate range‐use data for 19 individuals (6063–14 439 locations per bird). In habitats dominated by homogeneous cropland habitats, home‐ranges were over 12 ha in size, whereas in highly diverse habitats they were below 2 ha. Large home‐ranges were associated with increased flight activity (117% of that of birds in small home‐ranges) and distances travelled per night (152%), increased duration of foraging trips (169%) covering larger distances (246%), and reduced nest visiting rates (81%). The study therefore provides strong correlative evidence that Little Owls breeding in monotonous farmland habitats expend more time and energy for a lower benefit in terms of feeding rates than do birds in more heterogeneous landscapes. As nestling food supply is the main determinant of chick survival, these results suggest a strong impact of farmland characteristics on local demographic rates. We suggest that preserving and creating islands of high habitat diversity within uniform open agricultural landscapes should be a key target in the conservation of Little Owl populations.     

Habitat use of the raccon dog (Nyctereutes procyonoides) in north-eastern Germany

This study investigated habitat availability and its selection and preference by adult, resident raccoon dogs inhabiting the countryside in north-eastern Germany. Habitat composition within home ranges and within the whole study area was almost equal. Although percentage share of farmland and meadow was 16.35% smaller and 12.06% higher within the home ranges, respectively. All nine habitat types (farmland, forest, settlement, water, meadows, maize fields, small woods, reeds and hedges) were used opportunistically by raccoon dogs. No significant, recognisable difference for habitat preferences between seasons was detected. Male and female raccoon dog showed equal habitat preference pattern. A comparison of active and inactive locations in different habitats found no remarkable differences.Habitat composition of individual home ranges was used to classify animals. If the percentage of forest within a home range exceeded 50% the individual was classified as a ‘forest type’ raccoon dog. If the percentage of forest habitats within a home range was less than 5%, the share of pastureland was mean 81.82%±16.92 SD. Consequently the individual was classified as a ‘agrarian type’ raccoon dog. Neither habitat preference nor habitat selection process differed between the two ‘types’. Habitat use and preference is discussed with relation to the ability of the raccoon dog to expand its range towards Western Europe.     

Can pinewoods provide habitat for a deciduous forest specialist? A two-scale approach to the habitat selection of Bechstein's bat

Populations of Myotis bechsteinii in Sierra de Cazorla, Segura y Las Villas Natural Park (southwestern Spain) survive in a large, old-growth coniferous woodland, which is in contrast with known ecological preferences of the species. We tracked ten lactating females and studied patterns of habitat selection by Bechstein's bat (Myotis bechsteinii) at two spatial scales: macrohabitat and microhabitat, regarding forest essence (coniferous vs. deciduous). The tracked individuals always foraged within forested areas and did not use areas devoid of trees. At the macrohabitat level, no positive selection of deciduous stands was apparent, suggesting selection studies of coarse resolution may not be able to capture subtle selection patterns. At the microhabitat level Myotis bechsteinii selected deciduous patches within the coniferous matrix, therefore, our results corroborate the perception of this species as dependent of services provided by deciduous woodlands. Larger foraging home ranges and commuting distances as compared with other Mediterranean localities suggest that our studied population inhabits a marginal or suboptimal environment in terms of habitat quality. We argue that this population of Bechstein's bat has survived as a relict one probably as a consequence of fragmentation and transformation of deciduous forest ecosystems in the Mediterranean range.     

Home range and habitat selection of northern bobwhite coveys in an agricultural landscape

Northern bobwhites thrive in fine-grained landscapes with a diversity of early succession woodland, grassland, and agriculture-associated habitat types. Bobwhite conservation has proved challenging in the increasingly coarse-grained Midwestern landscape as simplified agricultural cropping systems are implemented at larger spatial scales. Regardless, managing agricultural landscapes on private lands is the primary opportunity to restore bobwhite populations in the Midwestern United States. Although bobwhite habitat requirements are well understood, habitat selection in contemporary Midwestern landscapes is not well understood, especially on private lands where populations are declining. We used compositional analysis to investigate second- (study area) and third- (home range) order habitat selection by radiomarked bobwhite coveys on 4 private land study areas in southwestern Ohio. Mean covey home range size was 26.1 ± 2.2 ha (n = 48). Although home ranges were established in areas with more grassland cover, bobwhites most strongly selected early succession woody habitat (e.g., fencerows and ditches) at all scales, and selection for grassland diminished between the study area and home range scales. Grassland selection varied among sites and was strongest on sites with more row crop area. Woodlots were avoided at the study area scale, but were selected within home ranges. Grassland cover, like that provided by contemporary conservation programs, is an essential component of bobwhite habitat in the Midwest, but our results suggest more emphasis should be placed on early succession woody cover. Woody cover associated with fencerows, ditches, and woodlots adjacent to food sources and breeding habitat will likely improve non-breeding season survival, which is an influential vital rate in northern populations. © 2012 The Wildlife Society.     

Roe deer at risk: teasing apart habitat selection and landscape constraints in risk exposure at multiple scales

Non‐consumptive effects of predators result from the cost of responses to perceived risk. Prey modulate risk exposure through flexible habitat selection at multiple scales which, in interaction with landscape constraints, determines their use of risky habitats. Identifying the relative contributions of landscape constraints and habitat selection to risk exposure is a critical first step towards a mechanistic understanding of non‐consumptive effects. Here, we provide an integrative multi‐scale study of roe deer spatial responses to variable hunting pressure along a landscape gradient of open habitats and dispersed refuges. Between low‐risk and high‐risk periods, we investigated shifts in 1) home‐range location, 2) probability of using risky habitats (between‐habitat scale) and 3) distance to the nearest refuge (within‐habitat scale). For 2) and 3), we disentangled the contributions of landscape constraints and habitat selection to risky habitat use. We found that when risk was high, roe deer did not shift their home‐range, but generally decreased their use of risky habitats, and sometimes reduced their distance to cover (particularly older animals). There was a functional response in between‐habitat selection, with animals living in more open landscapes responding more than those living in landscapes with more refuges. However, individuals living in more open landscapes avoided open risky habitat less. Finally, we found that among‐individual variation in risk exposure was generally, but not always, minimized by habitat selection across gradients of landscape constraints. To our knowledge, this is the first study simultaneously documenting prey responses to risk at the within‐habitat, between‐habitat and home‐range scales. Our results support the view that between‐habitat selection acts at a higher hierarchical level than within‐habitat selection, and provide a framework for disentangling the contributions of habitat selection and landscape constraints to risk exposure. Selection cannot always compensate for landscape constraints, indicating a need for further investigation of the processes underlying habitat selection.     

Ranging behaviour and habitat usage in black rhinoceros, Diceros bicornis, in a Kenyan sanctuary

Home range area and habitat utilization by translocated black rhinoceros Diceros bicornis were studied at Sweetwaters Rhino Sanctuary in the Laikipia district of Kenya. Home ranges were estimated from sightings and tracking data; home range area was very variable between individuals (range 2.25–14.39km², minimum convex polygons), and was independent of age or sex. Groups of rhinoceros shared common home ranges, with little or no overlap between groups; each group consisted of one adult male, one or more adult females and their calves, and sometimes immature animals. Rhinoceros utilize a variety of habitats, but within these show positive selection for certain habitats. Home ranges generally included more Euclea bush, and less grassland and Acacia bush than expected. Rhinoceros make use of regular resting places, or bedding sites, generally situated in bushland in secluded areas, often in dense thickets. Rhinoceros defaecate at dung piles or middens. Middens are located throughout the range not just on the boundaries; the highest density of middens was found in riverine woodland, and the lowest density in grassland and Acacia bush.     

Hierarchical habitat selection by woodland caribou: its relationship to limiting factors

Habitat selection is a hierarchical process that may yield various patterns depending on the scales of investigation. We employed satellite radio‐telemetry to examine patterns of habitat selection by female woodland caribou in central Saskatchewan at both coarse (seasonal range) and fine (daily area) scales. At each scale, we converted spatial data describing compositions of available and used habitat to standardised resource selection indices and examined them with multivariate analyses of variance. Seasonal ranges generally showed preferential inclusion of peatlands and black spruce dominated stands relative to recently disturbed stands and early seral stage forests. In all populations, caribou preferred peatlands and black spruce forests to all other habitat types at the daily area scale, in general, these patterns may reveal the effective avoidance of wolves, the primary factor limiting caribou throughout the boreal forest. In three populations where seasonal ranges showed the selective inclusion of either young jack pine stands or clearcuts along with peatlands and black spruce forests, we found a relative avoidance of the clearcuts and young jack pine stands at the daily area scale. As all caribou populations in the area are thought to be relics of a once more continuous distribution, the seasonal range selection by animals in disturbed areas may better describe historic rather than current habitat selection. We found inter‐annual variation in selection at the coarser spatial scale in one population, and inter‐seasonal variation in selection at the finer spatial scale in three populations, indicating that the relative grains of the spatial and temporal scales coincide. We were better able to explain the seasonal variations in finer scale selection by considering available forage, a factor less likely than predation to limit woodland caribou populations. The data agree with the theory that the spatial and temporal hierarchy of habitat selection reflects the hierarchy of factors potentially limiting individual fitness.