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Observing the behavior of a species during its offspring-rearing period can provide valuable insights that improve our understanding of the habitat conditions required to support successful reproduction. We used GPS location data collected during a period of high snowshoe hare abundance from 2018 to 2020 to examine den use and investigate the capacity of Canada lynx ( Lynx canadensis Kerr, 1792) mothers to access prey resources around their den sites throughout the stages of kit development. We tested the hypothesis that mothers would be heavily restricted in movement during the first 2 months after parturition, at which point their behavior would return to pre-parturient baseline. At this high-latitude study site (∼67°N), parturition occurred approximately 3 weeks later compared to lynx in the south (∼47°N). Additionally, home ranges and core areas of females were greatly reduced (3–11x) following parturition. These observations, along with an estimation of activity budgets, suggest that there are both spatial and temporal restrictions affecting movement away from den sites even after kits are greater than 2 months old, indicating that females are limited to accessing prey resources within a constrained area (i.e., ≤10 km²) while caring for dependent kits. 

In Subarctic and Arctic environments, daily patterns of activity and space-use are strongly influenced by interplay between seasonal abiotic factors and the corresponding responses of the biotic environment. Here we combined accelerometry with GPS telemetry of Canada lynx (Lynx canadensis (Kerr, 1792), n=12) in northern Alaska to test the hypotheses that lynx activity would peak during twilight throughout the year, coinciding with activity of their preferred prey, and that individuals with larger home ranges would have greater spatial displacement and expend more energy on movement. Lynx activity occurred throughout the 24h day and peaked during twilight, but variation among individuals was high and diel rhythms were sometimes only detectable using the finer resolution accelerometer data. Surprisingly, home range size was not correlated with movement costs estimated via acceleration, but step length and acceleration were correlated in a positive curvilinear fashion. However, step length was sometimes disproportionately lower than predicted by acceleration. Such intervals of high activity with low spatial displacement were often followed by periods of rest, suggesting they may be indicative of hunting in a restricted patch of habitat. We conclude that accelerometers can provide additional information to supplement GPS data, providing a more complete picture of animal behavior. 

Cyclical population dynamics are a common phenomenon in populations worldwide, yet the spatial organization of these cycles remains poorly understood. In this study, we investigated the spatial form and timing of a population collapse from 2018 to 2022 in Canada lynx (Lynx canadensis) across the northwest boreal forest. We analyzed survival, reproduction, and dispersal data from 143 individual global positioning system (GPS) collared lynx from populations across five study sites spanning interior Alaska to determine whether lynx displayed characteristics of a population wave following a concurrent wave in snowshoe hare (Lepus americanus) abundance. Reproductive rates declined across the study sites; however, site-level reproduction declined first in our easternmost study sites, supporting the idea of a population wave. Despite a clear increase in percent of dispersing lynx, there was no evidence of directional bias in dispersal following a hare population wave. Analysis did show increasingly poor survival for lynx dispersing to the east compared to combined resident and westward dispersal. This pattern is consistent with a survival-mediated population wave in lynx as the driver of the theorized population wave. The combination of these factors supports the idea of a hierarchical response to snowshoe hare population declines with a drop in lynx reproduction followed by increased dispersal, and finally reduced survival. All of this evidence is consistent with the expected characteristics of a population undergoing a traveling wave and supports the hypothesis that lynx presence may facilitate and mirror the underlying wave patterns in snowshoe hare. 

Abstract Wildfire is the most impactful disturbance regime in the North American boreal region, driving the structure and composition of forests across the region. Recent climate models predict that increasing fire intensity and frequency will result in a shift from a largely coniferous forest to one with a greater dominance by deciduous species. We investigated how an iconic predator of the boreal system, the Canada lynx (Lynx canadensis), moves through a range of burn scars (4–73 years old). Using GPS collars at 4‐h fix rates, we fitted integrated step selection models to lynx movements across an 80‐year post‐fire chronosequence to assess habitat selection in both deciduous and coniferous forests. We predicted that lynx would primarily select intermediately aged spruce and young deciduous stands, mirroring previous research on the habitat selection of their main prey, snowshoe hares (Lepus americanus). We found, however, that lynx habitat selection peaked at intermediately aged stands in both forest types, with selection for younger deciduous stands in the winter months. There was no seasonal change in coniferous stands as they experience little change in cover across seasons. We hypothesize that lynx select for habitats that maximize capture probability as opposed to simply habitats with the highest hare density. Together, these results show that lynx can be resilient to short‐term shifts toward intermediate‐aged stands. However, these benefits will likely diminish in the longer term as the decrease in fire return interval may reduce the prevalence of intermediate‐aged stands. 

Abstract Connectivity is determined by the degree to which inhospitable habitat matrices are permeable to gene flow. Successful gene flow requires that dispersing individuals travel to new populations, survive there, and finally, reproduce. Consequently, examinations of connectivity must consider both the permeability of the landscape and individual survival patterns, as surviving individuals are the only ones that have the potential to reproduce.We investigated functional connectivity of Canada lynx (Lynx canadensis) populations in the northwestern boreal forest using an unprecedented dataset of 207,957 relocations from 142 individual lynx. As a specialist predator of snowshoe hare (Lepus americanus), lynx populations follow a 10‐ to 12‐year population cycle, which lags a few years behind the population cycles of hares.We used integrated step selection analyses to quantify habitat selection, and Bayesian counting process implementation of wrapped Cauchy survival models to evaluate mortality risk during dispersal. We compared movement patterns and survival across behavioral states and population phases, following the a population decline.Our results showed few complete physical barriers to dispersal in the study region, with many lynx dispersing greater than 3000 km. Step‐selection analysis of lynx movement revealed a higher tolerance for poor quality habitats in dispersing lynx as compared to resident lynx, primarily in selection for rugged terrain and closer proximity to roads. These differences resulted in a higher estimate of landscape permeability for dispersing lynx compared to residents. When survival patterns were considered, there were increasingly stark differences between resident and dispersing lynx during population declines. Dispersing lynx faced markedly lower survival rates than resident lynx.Overall, this paints a picture of a more connected landscape during population highs, which becomes increasingly fragmented during population lows. Canada lynx populations appeared to have few impermeable barriers across the landscape, but they face periods of low functional connectivity driven by lower survival during population declines. This emphasizes the significance of maintaining high‐quality refugia habitats from which population rebounds can occur following cyclic lows. 

Abstract Recent empirical studies have quantified correlation between survival and recovery by estimating these parameters as correlated random effects with hierarchical Bayesian multivariate models fit to tag‐recovery data. In these applications, increasingly negative correlation between survival and recovery has been interpreted as evidence for increasingly additive harvest mortality. The power of these hierarchal models to detect nonzero correlations has rarely been evaluated, and these few studies have not focused on tag‐recovery data, which is a common data type. We assessed the power of multivariate hierarchical models to detect negative correlation between annual survival and recovery. Using three priors for multivariate normal distributions, we fit hierarchical effects models to a mallard (Anas platyrhychos) tag‐recovery data set and to simulated data with sample sizes corresponding to different levels of monitoring intensity. We also demonstrate more robust summary statistics for tag‐recovery data sets than total individuals tagged. Different priors led to substantially different estimates of correlation from the mallard data. Our power analysis of simulated data indicated most prior distribution and sample size combinations could not estimate strongly negative correlation with useful precision or accuracy. Many correlation estimates spanned the available parameter space (−1,1) and underestimated the magnitude of negative correlation. Only one prior combined with our most intensive monitoring scenario provided reliable results. Underestimating the magnitude of correlation coincided with overestimating the variability of annual survival, but not annual recovery. The inadequacy of prior distributions and sample size combinations previously assumed adequate for obtaining robust inference from tag‐recovery data represents a concern in the application of Bayesian hierarchical models to tag‐recovery data. Our analysis approach provides a means for examining prior influence and sample size on hierarchical models fit to capture–recapture data while emphasizing transferability of results between empirical and simulation studies. 

We studied the diet and reproductive success of Great Horned Owl (Bubo virginianus) at its northern range limit during an apparent high in the Snowshoe Hare (Lepus americanus) population. We performed diet analyses using images from fixed motion sensor cameras and pellet and prey remains collected at active nests, and gathered data on breeding success through camera and visual observations. Pellet data at 14 nests produced 1277 prey records consisting of 65–95% Snowshoe Hare biomass. Great Horned Owls ate 18 different prey types, with overall biomass consisting of 93% mammal, 7% bird, and less than 1% insects, frogs, and fish. The mean prey mass of 714 g (± 34 SE) was 2–25 times the mean prey mass of studies of this species at more southerly latitudes. Camera observations showed that Great Horned Owls delivered an average of 459 g/chick/d (± 75) throughout nesting. This was significantly (P = 0.005) higher than observations from Alberta, at 328–411 g/chick/d. Pellet/prey remains data showed that Great Horned Owls delivering a higher proportion of hares to their nestlings successfully raised more chicks (χ21 = 6.3, P = 0.012), highlighting the importance of this prey in the population dynamics of Great Horned Owl. In addition, we observed Snowshoe Hare removing pellets beneath nest sites, revealing an apparently undocumented bias to the use of pellet analysis.