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Dickie, Melanie; Cody, Michael; Avgar, Tal — 2019-11-01 <p>1. Space-use behaviour reflects trade-offs in meeting ecological needs and can have consequences for individual survival and population demographics. The mechanisms underlying space-use can be understood by simultaneously evaluating habitat selection and movement patterns, and fine-resolution locational data are increasing our ability to do so. 2. We use high-resolution location data and an integrated step-selection analysis to evaluate caribou, moose, bear, and wolf habitat selection and movement behavior in response to anthropogenic habitat modification, though caribou data were limited. Space-use response to anthropogenic linear features (LFs) by predators and prey are hypothesized to increase predator hunting efficiency and are thus believed to be a leading factor in woodland caribou declines in western Canada. 3. We found that all species moved faster while on LFs. Wolves and bears were also attracted towards LFs, whereas prey species avoided them. Predators and prey responded less strongly and consistently to natural features such as streams, rivers and lakeshores. These findings are consistent with the hypothesis that LFs facilitate predator movement and increase hunting efficiency, while prey perceive such features as risky. 4. Understanding the behavioural mechanisms underlying space-use patterns is important in understanding how future land-use may impact predator-prey interactions. Explicitly linking behaviour to fitness and demography will be important to fully understand the implications of management strategies.</p>

Ladle, Andrew; Avgar, Tal; Wheatley, Matthew; Stenhouse, Gordon B.; Nielsen, Scott; Boyce, Mark S.; Nielsen, Scott E. — 2018-10-24 1. Outdoor recreation on trail networks is a growing form of disturbance for wildlife. However, few studies have examined behavioural responses by large carnivores to motorised and non-motorised recreational activity-- a knowledge gap that has implications for the success of human access management aimed at improving habitat quality for wildlife. 2. We used an integrated step-selection analysis of grizzly bear (Ursus arctos) radiotelemetry data and a spatio-temporal model of motorised and non-motorised human recreational activity to examine the effect of human recreational activity along trails on both habitat selection and movement behaviour of individual bears. Grizzly bears were captured and radiocollared in the west-central Alberta Rocky Mountains and Foothills, and trail cameras were deployed on trails to obtain data on human recreational activity. 3. We found that models including data on recreational activity outperformed trail-proximity models when interactions with movement covariates were included. Responses were highly variable among individuals, and across classes; males, females and females with cubs. 4. Male and solitary female grizzly bears increased avoidance of trails with a high probability of motorised activity, as well as displaying increased movement rates in response to motorised recreation. Females with cubs did not increase avoidance, however they had the largest response with higher movement rates. In contrast, for all classes selection for proximity to trail increased when probability of non-motorised activity was high, and the effect on movement was dampened relative to the motorised response. 5. Synthesis and applications. By combining selection and movement into a unified modelling framework, we show that bears alter selection and movement behaviour in response to trails and recreation, and that such responses are determined by the type of recreational activity. Reduced selection and increased movement in proximity to motorised trails could affect bears’ ability to exploit foraging opportunities in these areas. Future access management actions for grizzly bear recovery should consider frequency and type of linear feature use by humans rather than solely relying on thresholds relating to feature densities.

Prokopenko, Christina M.; Boyce, Mark S.; Avgar, Tal — 2017-08-08 Roads are a prevalent, ever-increasing form of human disturbance on the landscape. In many places in western North America, energy development has brought human and road disturbance into seasonal winter range areas for migratory elk. We sought to evaluate the predictions from the risk-disturbance hypothesis when studying elk response to roads during winter. Road proximity and crossing were used to evaluate these behaviours, which offered a rare comparison between two common measures of roads. We used integrated step selection analysis (iSSA) to evaluate four alternative hypotheses regarding the influence of roads on space-use behaviour across 175 elk-years of elk telemetry data, and we quantified both population-level and individual-level variations in responses. We demonstrated, for the first time, how iSSA can be used to combine movement analysis in a refined approach to habitat selection. Elk responded to roads as they would natural predation risk. Elk selected areas farther from roads at all times of day with avoidance being greatest during twilight. In addition, elk sought cover and moved more when in the vicinity of roads. Road crossings were generally avoided, but this avoidance was weakest during daytime when elk were both moving and closer to roads. Synthesis and applications. Energy development is transforming landscapes in western North America with the proliferation of roads, which we show is having substantial and multifaceted negative effects on elk movement and behaviour. These adverse effects can be mitigated by minimizing new road construction and by restricting traffic on roads as well as providing the protection of tree cover on elk winter ranges. https://creativecommons.org/publicdomain/zero/1.0/

Broadley, Kate; Burton, Cole; Boutin, Stan; Avgar, Tal — 2020-11-20 <p>Camera-traps (CTs) are an increasingly popular tool for wildlife survey and monitoring. Estimating relative abundance in unmarked species is often done using detection rate as an index of relative abundance, which assumes a positive linear relationship with true abundance. This assumption may be violated if movement behavior varies with density, but the degree to which movement is density-dependent across taxa is unclear. The potential confounding of population-level relative abundance indices by movement depends on how regularly, and by what magnitude, movement rate and home-range size vary with density. We conducted a systematic review and meta-analysis to quantify relationships between movement rate, home range size, and density, across terrestrial mammalian taxa. We then simulated animal movements and CT sampling to test the effect of contrasting movement scenarios on CT detection rates. Overall, movement rate and home range size were negatively correlated with density and positively correlated with one another. The strength of the relationships varied significantly between taxa and populations.  In simulations, detection rates were related to true abundance but underestimated change, particularly for slower moving species with small home ranges. In situations where animal space use changes markedly with density, we estimate that up to thirty percent of a true change in abundance may be missed due to the confounding effect of movement, making trend estimation more difficult. The common assumption that movement remains constant across densities is therefore violated across a wide range of mammal species. When studying unmarked species using CT detection rates, researchers and managers should consider that such indices of relative abundance reflect both density and movement. Practitioners interpreting changes in detection rates should be aware that observed differences may be biased low relative to true changes in abundance, and that further information on animal movement may be required to make robust inferences on population trends.</p>

Avgar, Tal; Brown, Glen S.; Thompson, Ian; Rodgers, Art R.; Mosser, Anna; Fryxell, John M.; Patterson, Brent R.; Newmaster, Steven G.; Reid, Doug E. B.; Turetsky, Merritt; Hagens, Jevon S.; Reid, Douglas E. B.; Shuter, Jennifer; Baker, James A.; Kittle, Andrew M.; Mallon, Erin E.; McGreer, Madeleine T.; Street, Garrett M.; Turetsky, Merritt J. — 2016-01-20 1. Movement patterns offer a rich source of information on animal behaviour and the ecological significance of landscape attributes. This is especially useful for species occupying remote landscapes where direct behavioural observations are limited. In this study, we fit a mechanistic model of animal cognition and movement to GPS positional data of woodland caribou (Rangifer tarandus caribou; Gmelin 1788) collected over a wide range of ecological conditions. 2. The model explicitly tracks individual animal informational state over space and time, with resulting parameter estimates that have direct cognitive and ecological meaning. Three biotic landscape attributes were hypothesized to motivate caribou movement: forage abundance (dietary digestible biomass), wolf (Canis lupus; Linnaeus, 1758) density and moose (Alces alces; Linnaeus, 1758) habitat. Wolves are the main predator of caribou in this system and moose are their primary prey. 3. Resulting parameter estimates clearly indicated that forage abundance is an important driver of caribou movement patterns, with predator and moose avoidance often having a strong effect, but not for all individuals. From the cognitive perspective, our results support the notion that caribou rely on limited sensory inputs from their surroundings, as well as on long-term spatial memory, to make informed movement decisions. Our study demonstrates how sensory, memory and motion capacities may interact with ecological fitness covariates to influence movement decisions by free-ranging animals.

Ladle, Andrew; Avgar, Tal; Wheatley, Matthew; Boyce, Mark S. — 2017-09-07 Ecological patterns and processes often take place within linear-feature networks, and this has implications when analysing the spatial configuration of such patterns or processes across a landscape. One such pattern is the use of landscapes by human recreationists: an important variable in animal habitat selection and behaviour. Due to the difficulty in obtaining data, ecologists tend to use coarse metrics such as linear-feature density, while the extent and timing of human activity are often ignored. Remote detector equipment and its increasing use in ecological studies allow for large volumes of data on human activity to be collected. However, the analysis of these data still can be challenging. Using a combination of generalised linear mixed-effects models and network-based ordinary kriging, we developed a method for estimating spatial and temporal variations in motorised and non-motorised activities across a complex linear-feature network. Trail cameras were set up between 2012 and 2014 and monitored motorised and non-motorised activities at 238 different trail sites across a 2824 km2 region of the eastern slopes and foothills of central Alberta's Rocky Mountains. We evaluate the predictive capacity of this approach, demonstrate its application and discuss its merits and limitations. This method offers a straightforward analysis that can be applied to remotely acquired data to give a useful metric for assessing wildlife responses to human activity, and has potential application beyond the highlighted example.

Scrafford, Matthew A.; Avgar, Tal; Heeres, Rick; Boyce, Mark S. — 2017-12-01 Wildlife behavior when crossing roads is likely to mirror natural responses to predation risk including not responding, pausing, avoiding, or increasing speed during crossing. We generated coarse-scale behavioral predictions based on these expectations that could be assessed with GPS radiotelemetry. We evaluated our predictions using an integrated step-selection analysis of wolverine (Gulo gulo luscus) space use in relation to spatially and temporally dynamic vehicle traffic on industrial roads in northern Alberta. We compared support for alternative models of road avoidance, increased speed near roads, and road avoidance and increased speed near roads. We predicted that wolverines would avoid roads and increase their speed near roads and that these behaviors would increase with traffic volume. We found that vehicle traffic was relatively low (0 – 30 vehicles/12 hours) but important for explaining wolverine space use. Top winter and summer models indicated that wolverines avoided and increased speed near roads. Wolverine movement but not avoidance increased with traffic volume. We suggest that movement is a fine-scaled response that is more responsive to vehicle traffic than habitat selection. We show that roads, regardless of traffic volume, reduce the quality of wolverine habitats and act as barriers to movement and that higher-traffic roads might be most deleterious. We suggest that wildlife behavior near roads should be viewed as a continuum and that accurate modeling of behavior when near roads requires quantification of both movement and habitat selection. Mitigating the effects of roads on wolverines would require clustering roads, road closures, or access management.

Kim, Dongmin; Thompson, Peter R.; Wolfson, David W.; Merkle, Jerod A.; Oliveira-Santos, L. G. R.; Forester, James D.; Avgar, Tal; Lewis, Mark A.; Fieberg, John — 2024 Supplementary Material 1. https://creativecommons.org/licenses/by/4.0/legalcode