Habitat Use Research Articles

Boldness predicts foraging behaviour, habitat use and chick growth in a central place marine predator.

Animal personality can shape individual's fitness. Yet, the mechanistic relationship by which individual's personality traits lead to variations in fitness remains largely underexplored. Here, we used novel object tests to measure boldness of chick-provisioning Cory's shearwaters (Calonectris borealis) from a coastal colony off west Portugal, and deployed GPS loggers to study their at-sea behaviour and distribution. We then tested whether boldness predicts individual differences in adult's trophic ecology and variations in chick growth, to assess potential implications of personality-specific foraging behaviours. Foraging effort was higher for shyer than for bolder individuals, which, during short forays, exhibited larger foraging ranges, and foraged in regions of higher and more variable bathymetry. This suggests that nearby the colony bolder individuals expanded their foraging area to maximize resource acquisition and increase the probability of foraging success. When endeavouring to longer distances, bolder individuals exhibited comparably shorter foraging ranges and targeted low bathymetry regions, likely with enhanced prey availability, while shyer individuals exhibited much larger foraging ranges indicating greater flexibility when foraging in oceanic realms. Despite such differences between bolder and shyer individuals their isotopic niches were similar. Yet, chicks raised by bolder parents grew at a faster rate than those raised by shyer parents. Together, our results suggest that differences in resource acquisition strategies could play a key role through which individual's boldness may influence breeding performance, even when individuals have similar isotopic preferences.

Seasonal and diurnal marine mammal presence in the proposed marine protected area of Southampton Island, Hudson Bay, Nunavut as revealed by passive acoustic monitoring

Marine protected areas contribute to mitigating the effects of human activities on marine ecosystems. The waters of Southampton Island, Nunavut, Canada are under consideration to become a marine protected area, but baseline information of marine mammal presence and habitat use is lacking. This study represents the first passive acoustic monitoring of marine mammals in this area, with data collected in 2018 and 2019. Bioacoustics analyses and generalized linear models were used to investigate species seasonal and temporal vocalization trends; infer behavior and habitat use from vocal cues; and explore vocal activity correlation with sea ice. Over a diel period, bearded seals (Erignathus barbatus (Erxleben, 1777)) and walruses (Odobenus rosmarus (Linnaeus, 1758)) were found to increase their vocal activity at night, whereas belugas (Delphinapterus leucas (Pallas, 1776)) mainly vocalized during daytime. Seasonally, bearded seals were recorded only during their breeding season at sea ice break-up, while walruses vocalized consistently throughout the open-water period outside their breeding season. Beluga vocal trends suggest their use of the area as a migratory corridor during sea ice break-up and freeze-up. Finally, bowhead whales (Balaena mysticetus (Linnaeus, 1758)) were recorded later than expected, concurrently with the onset of their mating vocal displays during the fall migration at sea ice freeze-up.

How to count bird calls? Vocal activity indices may provide different insights into bird abundance and behaviour depending on species traits

Abstract Passive acoustic monitoring (PAM) has become an important tool for surveying birds, and there is a growing demand for approaches to obtain abundance and behavioural information from PAM recordings. Changes in bird populations have been assessed by counting recorded calls and calculating the vocal activity rate (VAR, i.e. the number of calls per recording time). However, bird calls could be counted in various ways and depending on species traits, these call counts could give us different insights on bird abundance, vocal behaviour and/or habitat use. Our study had two goals: (1) to present and evaluate two new indices based on call counts, the detection rate (DR, i.e. the number of 1‐min recordings in which the presence of a target vocalization is detected) and the maximum count per minute (MAX, i.e. the maximum number of calls found in a 1‐min recording); and (2) to present a conceptual framework showing how the interpretations of VAR, DR and MAX could depend on the index and on species traits. For three Neotropical bird species with distinct traits, we calculated VAR, DR and MAX based on PAM data from 25 sites in the Yucatan Peninsula (Mexico) that varied in their degree of anthropogenic habitat disturbance. We found moderate to high correlations between the indices and higher temporal variability in VAR compared to DR and MAX. We also found different effect sizes of habitat disturbance on the three species and indices. We suggest that DR might be a more reliable index of relative abundance than VAR for species whose calling behaviour exhibits a high cue rate and that MAX may be suitable for estimating family or flock size in gregarious birds. Our findings show the potential usefulness of developing new indices based on call counts to generate ecological hypotheses and assess changes in bird abundance and behaviour.

Multi-method approach identifies a South African estuary as an important elasmobranch habitat and potential nursery ground

Elasmobranchs play important ecological roles but are highly threatened. Understanding their habitat use and abundance is crucial for the management and conservation of these species and their habitats. While some species are known to use estuaries as vital habitats (e.g. feeding or nursery grounds), this remains an understudied area. A multi-method approach was used to survey the Keurbooms Estuary on the south coast of South Africa, over two years, to quantify the diversity, relative abundance and habitat use of elasmobranchs in this system. The survey methods were baited remote underwater video (BRUV), boat-based visual sightings, and unmanned aerial video (UAV). Opportunistic sightings were also collected. Six elasmobranch species were observed, with significant differences in community composition between the methods. Whereas effort was skewed towards BRUV surveys, the boat and UAV surveys recorded more elasmobranchs more frequently, and opportunistic sightings recorded the highest diversity. The common eagle ray Myliobatis aquila was the most abundant elasmobranch species and the only one recorded year-round; most individuals (93%) were juveniles, suggesting the Keurbooms Estuary may be a nursery area for this Critically Endangered species. The duckbill ray Aetomylaeus bovinus and common smoothhound shark Mustelus mustelus were observed during summer, the latter forming large aggregations. Another three ray species were recorded rarely. This study highlights the benefit of using a multi-method survey approach for shallow ecosystems and reveals the Keurbooms Estuary as an important habitat for elasmobranchs.

Informing conservation management of the bilby (Macrotis lagotis) in the Pilbara: a review of research and future directions

For threatened species that occur across multi-use landscapes, a coordinated cross-tenure management approach is desirable to achieve long-term conservation outcomes. To provide a comprehensive understanding of the progress towards achieving conservation priorities for the greater bilby (Macrotis lagotis) in the Pilbara region of Western Australia (WA), and inform ongoing research and funding investment, we review a research program that has focused on the species over the past decade. Priorities were initially established at a stakeholder workshop in 2013, and research targeting key areas has greatly enhanced ecological knowledge of the bilby in the Pilbara and elsewhere in WA. Highlights include the development of a non-invasive scat DNA-based abundance monitoring technique, an improved understanding of habitat use and diet, including the importance of Acacia spp. that host root-dwelling larvae, and the threat posed by introduced predators. Proposed future research directions focus on better understanding habitat requirements and the association between key food resources and fire, evaluating genetic structure and gene flow at the landscape-scale and examining threat interactions. Management to mitigate a range of threats including introduced predators, grazing livestock/feral herbivores and fire is recommended, with consideration for an integrated approach.

Hirundo rustica (Barn Swallows) and Tachycineta bicolor (Tree Swallows) select wetlands in agriculturally intensive landscapes, as revealed by GPS tracking

Abstract Aerial insectivorous birds breeding in North America have experienced decades of population declines for reasons hypothesized to be related to changes in their insect prey. In agricultural landscapes, land management practices affect insect communities, leading to concerns that ongoing trends toward more intensive cultivation could affect the ability of farmland-breeding aerial insectivores to forage and provision their offspring with aerial insect prey. To understand how differences in agricultural intensity may affect the foraging behavior of different aerial insectivore species, we used GPS tags to compare the foraging movements and foraging habitat use of 2 species with different foraging ecologies, Hirundo rustica (Barn Swallow) and Tachycineta bicolor (Tree Swallow), breeding at 17 sites in agricultural landscapes in Saskatchewan, Canada. Although we identified differences in foraging behavior consistent with each species’ reported ecological traits, including T. bicolor foraging farther and over larger areas than H. rustica, overall foraging behavior was similar between species. Resource selection function analyses indicated that both species used wetlands disproportionately often relative to local wetland availability, especially when detected farther from their nests. Hirundo rustica and T. bicolor both also avoided cropped foraging habitat, using it proportionally less than it was locally available. In landscapes with greater wetland cover, both species selected for wetland habitat more strongly, and among T. bicolor, higher wetland density decreased maximum foraging distance and home range area. In contrast, we found no effect of crop cover on foraging habitat selection or foraging movements. These findings suggest that H. rustica and T. bicolor breeding in Saskatchewan agroecosystems share similar foraging strategies, with wetland habitats appearing to be highly important despite comprising only a small proportion of land area. Overall, these results indicate that protecting wetland habitats should be a priority for aerial insectivore conservation in the intensive agricultural landscapes of the Canadian prairies.

Matrix-based key to the click beetle genera of Canada and USA with a summary of habitat use (Coleoptera, Elateridae)

The Elateridae, or click beetles are abundant and diverse in most terrestrial ecosystems in North America, acting as plant pests and filling many other ecological roles. The 112 genera of Elateridae Leach, 1815, or click beetles, known from Canada and USA are included in a first comprehensive digital interactive key to adults. A link to an online peer-reviewed LUCID key to elaterid genera and downloadable LUCID files are provided. Diagnostic morphological summaries using information from the 61 characters and 158 character states of the matrix key are presented for all genera. A table summarizes current understanding of habitat use by all elaterid genera in Canada and USA from literature, collections, citizen science, and our own observations. Diversity of elaterid genera was high throughout warm and cool temperate regions, especially in mountainous areas and mesic woodlands. Larvae of most genera were associated with soil, litter and decaying wood.

Bridging Cree knowledge and Western science to understand the decline in hunting success of migratory Canada geese

AbstractCanada goose (Branta canadensis) is one of the main waterfowl species harvested by Cree hunters in James Bay, Canada. Land users who hunt geese along coastal Eeyou Istchee (Eastern James Bay, Quebec) report that they are now much less successful in harvesting sub-arctic breeding geese (B. c. interior) than in the 1980s, especially during the fall hunting season. We followed a mixed-methods triangulation design in which we simultaneously gathered Indigenous and scientific knowledge. For the Indigenous knowledge, we conducted semi-structured interviews with Cree land users who shared their knowledge about how the goose populations that stage in Eeyou Istchee have changed within living memory. They attributed their reduced hunting success to fewer migrating geese and modification of their behavior. They also identified many environmental changes, especially the decline of eelgrass (Zostera marina), that may have affected the number, distribution, and migration patterns of Canada geese along the coastal Eeyou Istchee in the past 50 years. We complemented this information using waterfowl study techniques including aerial surveys, band recovery analyses, and GPS tracking of individually marked geese. Habitat changes both at the local scale in Eeyou Istchee and in other parts of the staging and wintering ranges of Canada geese, natural and human disturbances along the coast, and a gradual increase in molt migrant temperate breeding Canada geese (B. c. maxima) likely resulted in changes in habitat use and migration patterns of sub-arctic breeding Canada geese along the James Bay east coast. By bridging Cree knowledge and Western science, we identified the various factors that affect the harvest success of Eeyou Istchee goose hunters. Such an approach should be encouraged when Indigenous peoples rely upon migratory bird or mammal species that spend only a portion of their annual cycle within the hunting territories of land users.

Deer activity levels and patterns vary along gradients of food availability and anthropogenic development

Animal activity reflects behavioral decisions that depend upon environmental context. Prior studies typically estimated activity distributions within few areas, which has limited quantitative assessment of activity changes across environmental gradients. We examined relationships between two response variables, activity level (fraction of each day spent active) and pattern (distribution of activity across a diel cycle) of white-tailed deer (Odocoileus virginianus), with four predictors—deer density, anthropogenic development, and food availability from woody twigs and agriculture. We estimated activity levels and patterns with cameras in 48 different 10.36-km2 landscapes across three larger regions. Activity levels increased with greater building density, likely due to heightened anthropogenic disturbance, but did not vary with food availability. In contrast, activity patterns responded to an interaction between twigs and agriculture, consistent with a functional response in habitat use. When agricultural land was limited, greater woody twig density was associated with reduced activity during night and evening. When agricultural land was plentiful, greater woody twig density was associated with more pronounced activity during night and evening. The region with the highest activity level also experienced the most deer-vehicle collisions. We highlight how studies of spatial variation in activity expand ecological insights on context-dependent constraints that affect wildlife behavior.

Satellite tagging insights into the seasonal movements and behavior of Mediterranean spearfish (Tetrapturus belone, Istiophoridae)

The Mediterranean spearfish (Tetrapturus belone) is a highly migratory predator, also exploited by commercial and recreational fisheries although its catches are poorly reported. The fishing pressure on this species is currently unknown because catch and landing data are fragmentary. Furthermore, more ecological information (e.g. migratory movements) is needed to establish eventual management measures, and ICCAT has not examined the population status yet. Understanding species migratory movements is crucial for addressing conservation challenges and supporting management decisions. In this study we investigated the migratory movements, seasonal patterns, vertical behavior, and thermal preference of T. belone, with the aim to improve information on its ecology and behavior. Overall, six individuals were tagged in the Strait of Messina and Tyrrhenian Sea with pop-up satellite tags and their movements were mainly restricted to the central Mediterranean. Utilization distributions derived from geolocation revealed an overall and seasonal importance of the Tyrrhenian Sea and Strait of Sicily, as well as variability in winter habitat use. While the fish exhibited similar depth preference, spending the majority of time at depths ≤ 10 m, we observed that the Mediterranean spearfish is also able to perform sporadic deep dives below 200 m. Vertical movement showed a bimodal pattern common in other billfish species, characterized by occupation of shallower, warmer waters during the night and deeper, cooler waters during the day. This research increases knowledge on the migration ecology and habitat preference of T. belone which is important for management of this understudied species.

Isotopic niches reveal the trophic structure of the cetacean community in the oceanic waters around the Azores

IntroductionThe oceanic waters around the Azores host a high diversity of cetaceans, with 28 species of toothed and baleen whales present year-round or seasonally. This high cetacean biodiversity likely plays an important role in the structure, functioning and productivity of the ecosystem, and may increase trophic redundancy, thus contributing to food web resilience to disturbances.MethodsHere we used stable isotope (δ13C and δ15N) analysis to characterize trophic niches, assess niche overlap, describe the trophic structure and discuss potential redundancy in the cetacean community. Using 407 samples from 12 species, we estimated Standard Ellipse Areas and overlaps between species and used a hierarchical clustering analysis to identify trophic guilds.Results and discussionδ13C and δ15N values ranged from -20.53 to -15.46‰ and from 7.78 to 14.41‰ respectively, suggesting the use of diverse habitats and resources among cetacean species. Clustering analysis revealed that species were grouped into four trophic guilds, segregated mainly by trophic position (TP): a low-TP guild with three zooplanktivore baleen whales, a mid-TP guild with micronektivores, a high-TP guild with micronekton and nekton consumers, and a cluster with only Pseudorca crassidens. There was significant isotopic niche overlap between one pair of species within each guild, indicating some potential for trophic redundancy in the community. Yet, these pairs also showed some form of spatial or temporal partitioning, suggesting that mechanisms promoting species coexistence could play a key role in structuring the cetacean community in the region and in its ecological role.

Integration of Indigenous Research Methodologies, Traditional Ecological Knowledge and molecular scatology in an assessment of mesocarnivore presence, diet and habitat use on Yurok Ancestral Lands.

Partnerships between Tribes and researchers in wildlife monitoring and application of Traditional Ecological Knowledge (TEK) have taken a variety of forms, and some scholars have noted a need for culturally sensitive approaches. Guided by Indigenous Research Methodologies, this research is coupled with Yurok TEK, or hlkelonah 'ue-megetohl ('to take care of the earth'), enabling an applied, culturally sensitive approach in partnership with the Yurok Tribe. We present results from a molecular scatology study of wildlife within the ancestral territory of the Yurok Tribe. Scats were collected opportunistically on road transects. All samples (N = 132) were analysed via DNA barcoding and results matched to documented 'Oohl 'we-toh (Yurok language) names to determine the depositor species (N = 8). Though there were four focal mesocarnivore species in our study, only bobcat (Chmuuek; Lynx rufus) and gray fox (Wergers; Urocyon cinereoargenteus) were detected as depositor species. Post hoc analyses were conducted to explore distribution, habitat use and selection in a use-availability context, and food habits of these two species. We found almost complete separation of bobcat and gray fox use of transects, as well as indication of partitioning of vegetation cover types and food. We demonstrate an integrated framework of Western and Indigenous sciences that allows the Indigenous researcher to transcend structured academic disciplinary boundaries. Our approach can be modified for partnerships between Tribes, agencies, academics and students for wildlife monitoring in broader geographic regions in various research applications.

Defining the role of Sabellaria alveolata reefs as nursery areas for juvenile fish: first evidence from drone-based imagery and underwater visual census data

The biogenic reefs built by the honeycomb worm Sabellaria alveolata constitute priority habitats along Atlanto-Mediterranean coastal areas. Despite their wide extent and important ecological role, the nursery value of S. alveolata reefs remains unclear, and more information is needed to define how such structured habitats affect juvenile fish assemblages. In this study, habitat use by juveniles of 7 fish species was investigated by underwater visual census (UVC) at 3 study sites representing a gradient of complexity of Sabellaria reef habitats, spanning from a large and uniform reef to patchy and isolated small reef formations. Sabellaria reef metrics derived by drone-based cartography and GIS analysis were used to quantitatively monitor the seasonal structural changes occurring due to the natural dynamics of the reefs. We also tested the potential effect of Sabellaria habitats on the growth and relative condition factor (Kn) of white seabream Diplodus sargus juveniles. Five of the 7 surveyed species, especially sparid fishes, showed a clear preferential association with Sabellaria formations. Generalized additive modelling revealed a significant effect of the compactness ratio on estimated fish densities at high and low index values. The juvenile fish sampled on Sabellaria reefs exhibited higher values of Kn than those sampled on rocky habitats, supporting the hypothesis that structural complexity positively affected their condition. We provide evidence on habitat use by juveniles, suggesting that the presence of the Sabellaria reef may act as a nursery and affect local fish density in Mediterranean coastal waters.

A comparative study of the alternative life history of iteroparous salmonids

AbstractThe kelt phase of anadromous iteroparous salmonid life history remains mysterious, particularly aspects of their habitat use and factors influencing survival. Atlantic salmon and sea‐run brown trout were captured in the estuary during their return migration to the Vosso River, Norway, tagged with acoustic transmitters, and tracked in the watershed and estuary in three different years (2020–2023). We found a relatively narrow window of river exit timing among trout that survived overwinter, whereas salmon tended to leave during a more protracted period. Trout preferred overwintering in lakes within the river system, which provided for lower locomotor activity than fish that overwintered in pools in the river according to data from tri‐axial accelerometer transmitters. In contrast, Atlantic salmon tended to spend surprisingly little time in lakes even though the energy expenditure in this habitat is was seemingly lower for salmon that did overwinter in the lake. Our results demonstrate different use of habitat during overwintering and could suggest that measures to protect iteroparous life history strategies of salmonids will differently impact these two iteroparous salmonids.

Salmon shark seasonal site fidelity demonstrates the influence of scale on identifying potential high-use areas and vulnerabilities

Considering habitat use throughout the whole range of a highly mobile marine species is necessary to understand life history, identify vulnerabilities, and inform effective management. We used satellite tagging data from 128 adult female salmon sharks Lamna ditropis to identify seasonal hotspots of activity in an extended California Current region (ECCR; encompassing the California Current Large Marine Ecosystem), an area far away from their well-described primary habitat in the Alaska Downwelling Region where they have been documented, but whose utility has been poorly understood. Tag track durations had a mean of 447.7 ± 381 d, and 88 sharks (68.8%) visited the ECCR, comprising 33.6% of 28019 total daily Argos detections. Tracking data revealed that the timing and duration of migrations to the ECCR varied, but salmon shark distribution within the ECCR displayed consistent latitudinal shifts in accordance with regional oceanographic seasons. High site fidelity across multi-year tracks to high-productivity features, such as sea banks, and previously published knowledge of salmon shark life history suggest that the ECCR provides important foraging habitat which may be linked to reproductive success. The data reveal high overlap of salmon shark distribution with cumulative fishing effort collected by Global Fishing Watch for 2012-2019, particularly around seasonal hotspots, suggesting that female salmon sharks might be at risk of fisheries encounters. Collectively, our findings emphasize the importance of the ECCR in salmon shark life history and demonstrate the influence of spatial and temporal scale on interpretation of large movement data sets and identification of critical habitat outside of well-studied regions.

Preference for hibernacula microclimates varies among 3 bat species susceptible to white-nose syndrome

Abstract North American bat populations have experienced precipitous declines since the introduction of white-nose syndrome (WNS). Evidence that bats have responded to WNS by altering their winter habitat selection has been used to manipulate underground environments and improve winter survival. However, such management practices must be based on local data, which do not exist for all regions. Our goal was to identify determinants of winter habitat use for 3 bat species with varying susceptibility to WNS. To do so, we conducted 188 surveys of 129 potential hibernacula over 3 winters. We found that the range of winter temperatures and presence of water were important for the Little Brown Myotis (Myotis lucifugus) and Tricolored Bat (Perimyotis subflavus), species that are highly susceptible to WNS. Counts of both species were greater in sites with a narrow (<5 °C) temperature range and where streams or water bodies >25 m2 were present. In addition, we found larger groups of Little Brown Myotis in abandoned railroad tunnels than in caves. Winter counts of these species increased over time at 3 railroad tunnels that were surveyed for 3 consecutive winters, whereas populations were extirpated from historically important caves and mines. Counts of Big Brown Bats (Eptesicus fuscus), which are less susceptible to WNS, were also greater in hibernacula with water bodies. However, average winter temperature also helped predict counts of Big Brown Bats. This species had a curvilinear response to temperature, with most bats found at hibernacula with average winter temperatures of 4 to 6 °C, and fewer bats observed at warmer and colder conditions. These data show that focusing solely on historically important hibernacula may fail to achieve conservation goals for the Little Brown Myotis and Tricolored Bat in our region, and suggest that anthropogenic structures can provide habitat for remnant populations of imperiled bat species.

A family of process-based models to simulate landscape use by multiple taxa

ContextLand-use change is a key driver of biodiversity loss. Models that accurately predict how biodiversity might be affected by land-use changes are urgently needed, to help avoid further negative impacts and inform landscape-scale restoration projects. To be effective, such models must balance model realism with computational tractability and must represent the different habitat and connectivity requirements of multiple species.ObjectivesWe explored the extent to which process-based modelling might fulfil this role, examining feasibility for different taxa and potential for informing real-world decision-making.MethodsWe developed a family of process-based models (*4pop) that simulate landscape use by birds, bats, reptiles and amphibians, derived from the well-established poll4pop model (designed to simulate bee populations). Given landcover data, the models predict spatially-explicit relative abundance by simulating optimal home-range foraging, reproduction, dispersal of offspring and mortality. The models were co-developed by researchers, conservation NGOs and volunteer surveyors, parameterised using literature data and expert opinion, and validated against observational datasets collected across Great Britain.ResultsThe models were able to simulate habitat specialists, generalists, and species requiring access to multiple habitats for different types of resources (e.g. breeding vs foraging). We identified model refinements required for some taxa and considerations for modelling further species/groups.ConclusionsWe suggest process-based models that integrate multiple forms of knowledge can assist biodiversity-inclusive decision-making by predicting habitat use throughout the year, expanding the range of species that can be modelled, and enabling decision-makers to better account for landscape context and habitat configuration effects on population persistence.

Living on the edge: Insights into habitat patterns of forest-dwelling mammals in buffer zone of Melghat Tiger Reserve, India

Buffer zones surrounding protected areas act as interfaces between humans and wildlife, providing sustainable resource utilization while minimizing negative interactions. The human population in region is increasing at 15 % in decade. There are instances of human death and injury and cattle lifting by carnivores. Crop damage by wild herbivores is common. These factors create difficulties for the tiger reserve managers. Camera trap sampling was carried out in the buffer zone at a density of one camera trap pair every 2 km2 for a period of 33 to 46 days. Camera trap data were analyzed using occupancy modeling to estimate habitat use probability (Ψ) and detection probability (p). Naïve estimates of habitat use probability ranged from 0.11 to 0.64, while Ψ values based on occupancy modeling ranged from 0.23 to 0.71. The study showed fairly high level of habitat use by mammals in the buffer zone of the tiger reserve. Leopards were found to be associated with abundance of large prey species and human presence. Hyena, gaur and sambar showed an association with forest habitat while nilgai showed association with scrub. Chausingha and langur showed an association with sloping terrain. The study showed that buffer zones play an important role as wildlife habitat.

Predator-prey interactions across hunting mode, spatial domain size, and habitat complexities.

Predator-prey interactions are a fundamental part of community ecology, yet the relative importance of consumptive and nonconsumptive effects (NCEs) (defined as a risk-induced response that alters prey fitness) has not been resolved. Theory suggests that the emergence and subsequent predominance of consumptive or NCEs depend on the given habitat's complexity as well as predator hunting mode and spatial domain sizes of both predator and prey, but their relative influence on the outcome of predator-prey interactions is unknown. We built agent-based models in NetLogo to simulate predator-prey interactions for three hunting modes-sit-and-wait, sit-and-pursue, and active-while concurrently simulating large versus small spatial domain sizes for both predators and prey. We studied (1) how hunting mode and spatial domain size interact to influence the emergence of consumptive or NCEs and (2) how, when NCEs do dominate, hunting mode and spatial domain separately or additively determine prey shifts in time, space, and habitat use. Our results indicate consumptive effects only dominate for active predators when prey habitat domains overlap completely with the predator's spatial domain and when sit-and-wait and sit-and-pursue predators and their prey both have large spatial domains. Prey are most likely to survive when they shift their time but most frequently shift their habitat. Our paper helps to better understand the underlying mechanisms that drive consumptive or NCEs to be most dominant.

Ungulate niche partitioning and behavioural plasticity of aurochs in Early Holocene southern Scandinavia revealed by stable isotope analysis of bone collagen

This study examines the impact of the extensive climatic and environmental changes associated with the Early Holocene on the feeding ecology of aurochs, European bison, red deer, and Eurasian elk in southern Scandinavia from radiocarbon dates and analysis of stable carbon and nitrogen isotopes. Molecular sex information is utilised in the study of aurochs to understand the underlying reasons behind observed intraspecific differences. Asynchronous diachronic changes in dietary palaeoecology were observed between the included taxa. The observed trends in foraging and habitat use among herbivores in our dataset can be attributed to the directional vegetation change from open landscape to forest. Our findings imply that environmental changes and/or interspecific competition contributed to the local extinction of European bison and impacted the niches of remaining species through niche overlap (cervids) and partitioning (between cervids and aurochs). Thus, our observations are consistent with the influence of multiple mechanisms that acted concurrently.