Animal Space Use Research Articles

Resource selection by a megaomnivore in a marine foraging habitat

AbstractHabitat‐based approaches to animal conservation are bolstered by an understanding of resource selection, that is, use of resources (i.e., habitat features) relative to their availability in the environment. Quantifying resource selection is especially valuable when data characterizing animal space use are limited, as is often the case with mobile and/or cryptic species. Documenting associations with habitat features can better inform management in space in time, while also revealing key insight into movement ecology and behavior. Here, we evaluate resource selection by a megaomnivore whose highly mobile nature within marine habitats has resulted in an incomplete understanding of drivers of space use. We used satellite telemetry to track 29 green turtles (Chelonia mydas) from an eastern Pacific foraging aggregation in San Diego Bay, California, USA during 2013–2023. Tracking produced 5023 Fastloc‐GPS points which we used to model selection for local environmental resources relative to their availability. We employed logistic models to evaluate associations with seagrass, bathymetry, and water temperatures, implementing a framework that additionally allowed us to explore the roles of season, diel period, and turtle body size. Our methods demonstrate an approach for down‐weighting observations according to assumed telemetry error and autocorrelation. Results from fine‐scale resource selection models provide evidence that green turtles in San Diego Bay select for eelgrass meadows (Zostera marina), particularly during the warmest months of the year, but the strength of this selection changes from day to night. We additionally found day–night shifts in depth and temperature selection that changed with turtle body size and season. We discuss these findings in the context of diel patterns in resting and foraging behavior in addition to seasonal changes in thermally sensitive metabolic rates. Our study documents resource associations and provides quantitative information for the management of sea turtle foraging populations and their habitats. We offer key insight into habitat use by green turtles in the eastern Pacific at a pivotal time when multiple indicators point to population growth and expansion within the region.

High waterhole visitation rate by a breeding female snow leopard in summer

Water is a limiting resource in arid environments where space use of animals is often driven by access to water during the dry times of the year. Here we report on a breeding female snow leopard visiting a waterhole 37 times in June and July in 2015. These observations show that space use of snow leopards can be driven strongly by access to water during certain times of the year such as when lactating and the need for water is increased. Strong dependence on water during certain times of the year suggest that climate change and high human pressure on limited water sources may have negative impact on snow leopards and other wildlife in the mountains of High Asia.

Droughts reshape apex predator space use and intraguild overlap.

Droughts are increasing in frequency and severity globally due to climate change, leading to changes in resource availability that may have cascading effects on animal ecology. Resource availability is a key driver of animal space use, which in turn influences interspecific interactions like intraguild competition. Understanding how climate-induced changes in resource availability influence animal space use, and how species-specific responses scale up to affect intraguild dynamics, is necessary for predicting broader community-level responses to climatic changes. Although several studies have demonstrated the ecological impacts of drought, the behavioural responses of individuals that scale up to these broader-scale effects are not well known, particularly among animals in top trophic levels like large carnivores. Furthermore, we currently lack understanding of how the impacts of climate variability on individual carnivore behaviour are linked to intraguild dynamics, in part because multi-species datasets collected at timescales relevant to climatic changes are rare. Using 11 years of GPS data from four sympatric large carnivore species in southern Africa-lions (Panthera leo), leopards (Panthera pardus), African wild dogs (Lycaon pictus) and cheetahs (Acinonyx jubatus)-spanning 4 severe drought events, we test whether drought conditions impact (1) large carnivore space use, (2) broad-scale intraguild spatial overlap and (3) fine-scale intraguild interactions. Drought conditions expanded space use across species, with carnivores increasing their monthly home range sizes by 35% (wild dogs) to 66% (leopards). Drought conditions increased the amount of spatial overlap between lions and subordinate felids (cheetahs and leopards) by up to 119%, but only lion-cheetah encounter rates were affected by these changes, declining in response to drought. Our findings reveal that drought has a clear signature on the space use of multiple sympatric large carnivore species, which can alter spatiotemporal partitioning between competing species. Our study thereby illuminates the links between environmental change, animal behaviour and intraguild dynamics. While fine-scale avoidance strategies may facilitate intraguild coexistence during periodic droughts, large carnivore conservation may require considerable expansion of protected areas or revised human-carnivore coexistence strategies to accommodate the likely long-term increased space demands of large carnivores under projected increases in drought intensity.

Determinants of macaques' space use: A test for the ecological constraints model using GPS collars.

As a central topic in Behavioral Ecology, animal space use involves dynamic responses to social and ecological factors. We collared 22 rhesus macaques (Macaca mulatta) from six groups on Neilingding Island, China, and collected 80,625 hourly fixes over a year. Using this high-resolution location data set, we quantified the macaques' space use at the individual level and tested the ecological constraints modelwhile considering various environmental and human interfering factors. As predicted by the ecological constraints model, macaques in larger groups had longer daily path lengths (DPLs) and larger home ranges. We found an inverted U-shape relationship between mean daily temperatures and DPLs, indicating that macaques traveled farther on mild temperature days, while they decreased DPLs when temperatures were too high or too low. Anthropogenic food subsidies were positively correlated to DPLs, while the effect of rainfall was negative. Macaques decreased their DPLs and core areas when more flowers and less leaves were available, suggesting that macaques shifted their space use patterns to adapt to the seasonal differences in food resources. By applying GPS collars on a large number of individuals living on a small island, we gained valuable insights into within-group exploitation competition in wild rhesus macaques.

No evidence for the consistent effect of supplementary feeding on home range size in terrestrial mammals.

Food availability and distribution are key drivers of animal space use. Supplemental food provided by humans can be more abundant and predictable than natural resources. It is thus believed that supplementary feeding modifies the spatial behaviour of wildlife. Yet, such effects have not been tested quantitatively across species. Here, we analysed changes in home range size owing to supplementary feeding in 23 species of terrestrial mammals using a meta-analysis of 28 studies. Additionally, we investigated the moderating effect of factors related to (i) species biology (sex, body mass and taxonomic group), (ii) feeding regimen (duration, amount and purpose), and (iii) methods of data collection and analysis (source of data, estimator and spatial confinement). We found no consistent effect of supplementary feeding on changes in home range size. While an overall tendency of reduced home range was observed, moderators varied in the direction and strength of the trends. Our results suggest that multiple drivers and complex mechanisms of home range behaviour can make it insensitive to manipulation with supplementary feeding. The small number of available studies stands in contrast with the ubiquity and magnitude of supplementary feeding worldwide, highlighting a knowledge gap in our understanding of the effects of supplementary feeding on ranging behaviour.

Variation in farming damselfish behaviour creates a competitive landscape of risk on coral reefs.

Interspecific interactions are fundamental drivers of animal space use. Yet while non-consumptive effects of predation risk on prey space use are well-known, the risk of aggressive interactions on space use of competitors is largely unknown. We apply the landscape of risk framework to competition-driven space use for the first time, with the hypothesis that less aggressive competitors may alter their behaviour to avoid areas of high competitor density. Specifically, we test how aggressive risk from territorial algal-farming damselfishes can shape the spatial distribution of herbivore fish competitors. We found that only the most aggressive damselfish had fewer competitors in their surrounding area, demonstrating that individual-level behavioural variation can shape spatial distributions. In contradiction to the landscape of risk framework, abundances of farming damselfish and other fishes were positively associated. Our results suggest that reef fishes do not simply avoid areas of high damselfish abundance, but that spatial variation in aggressive behaviour, rather than of individuals, created a competitive landscape of risk. We emphasize the importance of individual-level behaviour in identifying patterns of space use and propose expanding the landscape of risk framework to non-predatory interactions to explore cascading behavioural responses to aggressive risk.

The relative importance of metabolic rate and body size to space use behavior in aquatic invertebrates.

Elucidating the underlying mechanisms behind variations of animal space and resource use is crucial to pinpoint relevant ecological phenomena. Organism's traits related to its energy requirements might be central in explaining behavioral variation, as the ultimate goal of a forager is to fulfill its energy requirements. However, it has remained poorly understood how energy requirements and behavioral patterns are functionally connected. Here we aimed to assess how body mass and standard metabolic rate (SMR) influence behavioral patterns in terms of cumulative space use and time spent in an experimental patchy environment, both within species and among individuals irrespective of species identity. We measured the behavioral patterns and SMR of two invertebrate species, that is, amphipod Gammarus insensibilis, and isopod Lekanesphaera monodi, individually across a range of body masses. We found that species of G. insensibilis have higher SMR level, in addition to cumulatively exploring a larger space than L. monodi. Cumulative space use scaled allometrically with body mass, and it scaled isometrically with SMR in both species. While time spent similarly in both species was characterized by negative body mass and SMR dependence, it was observed that L. monodi individuals tended to stay longer in resource patches compared to G. insensibilis individuals. Our results further showed that within species, body mass and metabolic rate explained a similar amount of variation in behavior modes. However, among individuals, regardless of species identity, SMR had stronger predictive power for behavioral modes compared to body mass. This suggests that SMR might offer a more generalized and holistic description of behavioral patterns that extend beyond species identity. Our study on the metabolic and body mass scaling of space and resource use behavior sheds light on higher-order ecological processes such as species' competitive coexistence along the spatial and trophic dimensions.

Social interactions and habitat structure in understanding the dynamic space use of invasive wild pigs

Untangling the abiotic and biotic feedback mechanisms driving animal movements and ranges is a core question in ecology, yet progress is hampered by inadequate modelling procedures. Here we show how a recently developed process‐based modelling approach, combining step‐selection functions and individual‐based models, enables a flexible method to infer movement drivers and multi‐scale emergent space use patterns. As a case study, we examine the movement behaviours of a highly invasive social generalist (wild pigs, Sus scrofa) in relation to conspecific space use and multiple land cover types in a complex agricultural landscape, showing that social interactions are predominantly more important to this species than selection for land cover. Thus, animal movement studies should not neglect the effects of sociality when inferring resource driven movements and, crucially, use multi‐scale techniques that incorporate movement processes to untangle drivers of animal space use.

Consistency in Verreaux's sifaka home range and core area size despite seasonal variation in resource availability as assessed by Enhanced Vegetation Index (EVI).

Primates are adept at dealing with fluctuating availability of resources and display a range of responses to minimize the effects of food scarcity. An important component of primate conservation is to understand how primates adapt their foraging and ranging patterns in response to fluctuating food resources. Animals optimize resource acquisition within the home range through the selection of resource-bearing patches and choose between contrasting foraging strategies (resource-maximizing vs. area-minimizing). Our study aimed to characterize the foraging strategy of a folivorous primate, Verreaux's sifaka (Propithecus verreauxi), by evaluating whether group home range size varied between peak and lean leaf seasons within a seasonally dry tropical forest in Madagascar. We hypothesized that Verreaux's sifaka used the resource maximization strategy to select high-value resource patches so that during periods of resource depression, the home range area did not significantly change in size. We characterized resource availability (i.e., primary productivity) by season at Kirindy Mitea National Park using remotely-sensed Enhanced Vegetation Index data. We calculated group home ranges using 10 years of focal animal sampling data collected on eight groups using both 95% and 50% kernel density estimation. We used area accumulation curves to ensure each group had an adequate number of locations to reach seasonal home range asymptotes. Neither 95% home ranges nor 50% core areas differed across peak and lean leaf resource seasons, supporting the hypothesis that Verreaux's sifaka use a resource maximization strategy. With a better understanding of animal space use strategies, managers can model anticipated changes under environmental and/or anthropogenic resource depression scenarios. These findings demonstrate the value of long-term data for characterizing and understanding foraging and ranging patterns. We also illustrate the benefits of using satellite data for characterizing food resources for folivorous primates.

Effects of food supplementation and helminth removal on space use and spatial overlap in wild rodent populations.

Animal space use and spatial overlap can have important consequences for population-level processes such as social interactions and pathogen transmission. Identifying how environmental variability and inter-individual variation affect spatial patterns and in turn influence interactions in animal populations is a priority for the study of animal behaviour and disease ecology. Environmental food availability and macroparasite infection are common drivers of variation, but there are few experimental studies investigating how they affect spatial patterns of wildlife. Bank voles (Clethrionomys glareolus) are a tractable study system to investigate spatial patterns of wildlife and are amenable to experimental manipulations. We conducted a replicated, factorial field experiment in which we provided supplementary food and removed helminths in vole populations in natural forest habitat and monitored vole space use and spatial overlap using capture-mark-recapture methods. Using network analysis, we quantified vole space use and spatial overlap. We compared the effects of food supplementation and helminth removal and investigated the impacts of season, sex and reproductive status on space use and spatial overlap. We found that food supplementation decreased vole space use while helminth removal increased space use. Space use also varied by sex, reproductive status and season. Spatial overlap was similar between treatments despite up to threefold differences in population size. By quantifying the spatial effects of food availability and macroparasite infection on wildlife populations, we demonstrate the potential for space use and population density to trade-off and maintain consistent spatial overlap in wildlife populations. This has important implications for spatial processes in wildlife including pathogen transmission.

Combining animal interactions and habitat selection into models of space use: a case study with white‐tailed deer

Animals determine their daily movement trajectories in response to a network of ecological processes, including interactions with other organisms, their memories of previous events, and the changing environment. These combine to cause the emergent space use patterns observed over longer periods of time, such as a whole season. Understanding which processes cause these patterns to emerge, and how, requires a process‐based modelling approach. Individual‐based decisions can be described as a system of partial‐differential equations (PDEs) to produce a dynamic description of space use built from the underlying movement process. Here we combine PDE‐based models with step‐selection analysis to investigate the combined effects of three established ecological processes that partially shape movement and space use: 1) a heterogeneous environment; 2) the environmental markings of moving conspecifics; and 3) the memory of direct interactions with conspecifics. We apply this framework to a large GPS‐based dataset of white‐tailed deer Odocoileus virginianus in the southeastern US. We fit models at the population level to provide predictive models, then tailor these to fit individual deer. We specifically incorporate relationships between each possible pair of deer and define each animal's responses to their unique local environments using separate integrated step‐selection analyses. We show how individual movements and decisions yield emergent patterns in animal distributions, and we provide a full generalised description of the framework so that it may be applied to any species simultaneously responding to multiple potentially interacting stimuli (e.g. sociality, morphology, etc.). We found that the population of bucks had highly varied preferences for vegetation, but were shaping their space use in response to conspecific interactions, dependent on the individual relationships between two deer. We advocate for increased consideration of individual‐based movement rules as determinants of realized animal space use, and particularly how these affect emergent distributions of entire species.

TrackdAT, an acoustic telemetry metadata dataset to support aquatic animal tracking research

Data on the movement and space use of aquatic animals are crucial to understand complex interactions among biotic and abiotic components of ecosystems and facilitate effective conservation and management. Acoustic telemetry (AT) is a leading method for studying the movement ecology of aquatic animals worldwide, yet the ability to efficiently access study information from AT research is currently lacking, limiting advancements in its application. Here, we describe TrackdAT, an open-source metadata dataset where AT research parameters are catalogued to provide scientists, managers, and other stakeholders with the ability to efficiently identify and evaluate existing peer-reviewed research. Extracted metadata encompasses key information about biological and technical aspects of research, providing a comprehensive summary of existing AT research. TrackdAT currently hosts information from 2,412 journal articles published from 1969 to 2022 spanning 614 species and 380,289 tagged animals. TrackdAT has the potential to enable regional and global mobilization of knowledge, increased opportunities for collaboration, greater stakeholder engagement, and optimization of future ecological research.

Counter-strategies to infanticide: The importance of cubs in determining lion habitat selection and social interactions.

Animal social and spatial behaviours are inextricably linked. Animal movements are driven by environmental factors and social interactions. Habitat structure and changing patterns of animal space use can also shape social interactions. Animals adjust their social and spatial behaviours to reduce the risk of offspring mortality. In territorial infanticidal species, two strategies are possible for males: they can stay close to offspring to protect them against rivals (infant-defence hypothesis) or patrol the territory more intensively to prevent rival intrusions (territorial-defence hypothesis). Here, we tested these hypotheses in African lions (Panthera leo) by investigating how males and females adjust their social and spatial behaviours in the presence of offspring. We combined datasets on the demography and movement of lions, collected between 2002 and 2016 in Hwange National Park (Zimbabwe), to document the presence of cubs (field observations) and the simultaneous movements of groupmates and competitors (GPS tracking). We showed a spatial response of lions to the presence of offspring, with females with cubs less likely to select areas close to waterholes or in the periphery of the territory than females without cubs. In contrast, these areas were more selected by males when there were cubs in the pride. We also found social responses. Males spent more time with females as habitat openness increased but the presence of cubs in the pride did not influence the average likelihood of observing males with females. Furthermore, rival males relocated further after an encounter with pride males when cubs were present in the prides, suggesting that the presence of cubs leads to a more vigorous repulsion of competitors. Males with cubs in their pride were more likely to interact with male competitors on the edge of the pride's home range and far from the waterholes, suggesting that they are particularly assiduous in detecting and repelling rival males during these periods. In general, the strategies to avoid infanticide exhibited by male lions supported the territorial-defence hypothesis. Our study contributes to answer the recent call for a behavioural ecology at the spatial-social interface.

Simulating animal space use from fitted integrated Step‐Selection Functions (iSSF)

Abstract A standing challenge in the study of animal movement ecology is the capacity to predict where and when an individual animal might occur on the landscape, the so‐called, utilisation distribution (UD). Under certain assumptions, the steady‐state UD can be predicted from a fitted exponential habitat selection function. However, these assumptions are rarely met. Furthermore, there are many applications that require the estimation of transient dynamics rather than steady‐state UDs (e.g. when modelling migration or dispersal). Thus, there is a clear need for computational tools capable of predicting UDs based on observed animal movement data. Integrated Step‐Selection Analyses (iSSAs), which integrates movement of the animal into habitat selection analyses, are widely used to study habitat selection and movement of wild animals, and result in a fully parametrised individual‐based model of animal movement, which we refer to as an integrated Step Selection Function (iSSF). An iSSF can be used to generate stochastic animal paths based on random draws from a series of Markovian redistribution kernels, each consisting of a selection‐free, but possibly habitat‐influenced, movement kernel and a movement‐free selection function. The UD can be approximated by a sufficiently large set of such stochastic paths. Here, we present a set of functions in R to facilitate the simulation of animal space use from fitted iSSFs. Our goal is to provide a general purpose simulator that is easy to use and is part of an existing workflow for iSSAs (within the amt R package). We demonstrate through a series of applications how the simulator can be used to address a variety of questions in applied movement ecology. By providing functions in amt and coded examples, we hope to encourage ecologists using iSSFs to explore their predictions and model goodness‐of‐fit using simulations, and to further explore mechanistic approaches to modelling landscape connectivity.

A harvest framework for a recovering American black bear population

AbstractHaving reproducible and transparent science‐based processes in wildlife management ensures the integrity of decision making. These processes are particularly important when establishing harvest frameworks, as guiding information in the peer‐reviewed literature is limited. We provide an example using multiple data sets, whose products guided aspects of the development of a harvest framework for a population of recolonizing American black bears (Ursus americanus) in Missouri, USA. To characterize the spatial distribution of harvest, we used 10 years (2010–2019) of black bear global positioning system (GPS) location data and 30 years (1991–2020) of sightings data to assess spatial vulnerability to harvest as the intersection among information on bear occurrence, bear sightings, and hunter land‐use tendencies (i.e., the avoidance of steep slopes, large distances from roads). We then used the spatial vulnerability assessment, information on the distribution of public and private lands, and easily discernable boundaries (i.e., major highways, rivers) to suggest boundaries for bear management zones. Additionally, to identify the timing of harvest that would limit female harvest bias, we assessed the temporal vulnerability of harvest using sex‐based changes in average daily step lengths and monthly utilization distribution sizes during fall. Black bear occurrence and sighting propensity was greater in southwestern Missouri, and potential hunter land use appeared pervasive across the landscape given the lack of landscape features that would disincentivize use. Given the influence of black bear occurrence and sighting propensity, spatial harvest vulnerability diminished from southern and southeastern to central portions of Missouri, with areas north of the Missouri River not a part of the established black bear range. We consequently divided areas south of the Missouri River into 3 black bear management zones: a small southwestern zone with primarily private lands and high harvest vulnerability, a southeastern zone that encompassed considerable public lands and moderate amounts of vulnerability, and a central zone that was composed mainly of areas of low vulnerability. Temporally, males did not exhibit movement‐based changes, but females became less active after the first week of October and used 63.9% less area through fall. Based on movements rates of males and females, a hunting season after the first week of October could reduce the likelihood of females being harvested. Harvests from the black bear harvest season in 2021 suggest that the proportion of bears harvested in each zone was similar in distribution to the proportion of permits allocated across zones with no harvest sex bias, which was aligned with agency goals. Animal movement and space use data products can guide harvest framework decision‐making.

Territorial behaviour of thrush nightingales outside the breeding season.

Territoriality is a common pattern of space use in animals that has fundamental consequences for ecological processes. In the tropics, all-year resident songbirds usually hold territories throughout the year, whereas most all-year resident temperate species are territorial only during the breeding season. In long-distance migrants, however, the situation is mostly unexplored. Here, we report findings from a Palaearctic-African migrant, the thrush nightingale Luscinia luscina. We found that only a fraction of the males was territorial in their East African winter quarters and that this was related to the stage of their song development. Individuals with full song were territorial towards other full songsters, but not towards birds that sang plastic song (i.e. an earlier stage of song development). Plastic singers were not territorial towards full songsters and often settled closely to territorial males. We suggest that territoriality of thrush nightingales in the winter quarters may be a by-product of rising testosterone levels that trigger song crystallization. Collectively, our study indicates that changes in territoriality can occur rapidly, giving rise to shifting proportions of territorial and non-territorial individuals in a population, which may lead to complex dynamics in settlement patterns and resulting ecological interactions.

Bird movement patterns in an agricultural landscape are mediated by both habitat conditions and traits

AbstractAlterations of the landscape following agricultural expansion and intensification affect animal movement patterns in the resulting mosaic of fragments and surrounding matrix. Here, we analyze the observed movement patterns of 34 individuals from nine tropical bird species from a rapidly changing agricultural landscape in Kenya. We deconstructed the movement patterns into their three components: step length, turn angles, and displacement and categorized them into two states: area restrictive and expansive movement. Using hidden Markov models, mixed models, and species traits, we showed that movement of birds in the fragments comprised of short step lengths and small displacements, characteristic of area restrictive movement to exploit high‐quality habitats. On the contrary, movement in the matrix comprised of long step lengths and large displacements, characteristic of area expansive movement to explore or pass‐through poorer habitats. The responses of movement components to fragments and the surrounding matrix were mediated by species traits. Habitat specialists showed stronger boundary response, shorter step lengths, and smaller displacements than habitat generalists in both the fragments and the matrix. Their strong preferences for the fragments, coupled with low flight capabilities can make movement in the matrix particularly difficult. Whereas, at the landscape scale, habitat generalist omnivores and habitat specialist frugivores had larger step lengths than the other guilds, as they use the matrix for resources or as a conduit to movement. Therefore, the habitat fragments are intensely utilized and of conservation importance. The matrix quality and permeability can promote animal space use and movement.

Animal and plant space-use drive plant diversity-productivity relationships.

Plant community productivity generally increases with biodiversity, but the strength of this relationship exhibits strong empirical variation. In meta-food-web simulations, we addressed if the spatial overlap in plants' resource access and animal space-use can explain such variability. We found that spatial overlap of plant resource access is a prerequisite for positive diversity-productivity relationships, but causes exploitative competition that can lead to competitive exclusion. Space-use of herbivores causes apparent competition among plants, resulting in negative relationships. However, space-use of larger top predators integrates sub-food webs composed of smaller species, offsetting the negative effects of exploitative and apparent competition and leading to strongly positive diversity-productivity relationships. Overall, our results show that spatial overlap of plants' resource access and animal space-use can greatly alter the strength and sign of such relationships. In particular, the scaling of animal space-use effects opens new perspectives for linking landscape processes without effects on biodiversity to productivity patterns.

A test of the green wave hypothesis in omnivorous brown bears across North America

Herbivorous animals tend to seek out plants at intermediate phenological states to improve energy intake while minimizing consumption of fibrous material. In some ecosystems, the timing of green‐up is heterogeneous and propagates across space in a wave‐like pattern, known as the green wave. Tracking the green wave allows individuals to prolong access to higher‐quality forage. While there is a plethora of empirical support for such behavior in herbivorous taxa, the green wave hypothesis (GWH) is nuanced based on factors such as body morphometrics and digestive capacity. Furthermore, little is known about whether other taxa, such as omnivores, track the green wave. Our objective was to assess whether the GWH can be extended to explain the movements of omnivores. Using GPS collar data from seven populations (n = 127 individuals) of brown bears Ursus arctos across their entire North American range, we first tested whether bears tracked the green wave. Using conditional resource selection functions (RSFs), we found that variation in proxies of vegetative forage quality better explained movement and habitat selection than proxies of forage biomass in over half of the bears in our study, providing evidence of green wave tracking. Second, we assess factors that explained variation in green wave tracking using linear mixed effects models. Green wave tracking in brown bears was explained by the variation in availability of green‐up within spring home ranges, and how green‐up transitioned across those home ranges. Our results demonstrate that the GWH can partially explain movement of a non‐migratory omnivorous species, extending the generality of the GWH as a broad predictor of animal space use. The green wave is another resource wave brown bears track, and our findings help predict brown bear space use, which can be used to guide conservation and habitat restoration efforts.

A telemetry study shows that an endangered nocturnal avian species roosts in extremely dry habitats to avoid predation

Describing animal space use is essential for understanding their ecological needs and for planning effective conservation schemes. Notably, certain biomes and life histories are understudied due to methodological challenges in tracking animals in their natural habitats. Specifically, both arid environments and nocturnal species are not sufficiently researched compared to diurnal species and to other biomes. This knowledge gap hinders our ability to properly prioritize habitats for species protection in areas undergoing human-related development. Here, we investigate the movement ecology of the Egyptian Nightjar (Caprimulgus aegyptius) in the arid Dead-sea region of Israel, the Palestinian Authority (the West Bank) and Jordan. This nocturnal insectivore is a cryptic desert-dweller and was considered locally extinct until it was rediscovered in 2016. For this work we tracked twelve individuals using GPS tags to determine how this resource-poor environment affects their home range, (predicting large areas), habitat use, and day-roost ecology. We found that the tracked Egyptian Nightjars had a much larger home range area than other Nightjar species, commuting nightly between foraging grounds and day-roosts. We found, as expected, intensive foraging activity at agricultural fields, where artificial irrigation likely supports higher resource (insect) density. Additionally, we found that individuals showed very high roosting site fidelity, often returning to the same specific site, located in extremely dry and exposed habitats, presumably for predator avoidance. This finding highlights the ecological value of these barren habitats that are often considered “lifeless” and therefore of lower priority for conservation. Consequently, our research demonstrates the importance of describing the space-use of nocturnal animals in arid habitats for conservation efforts.