Absence of SARS-CoV-2 in wildlife of northeastern Minnesota and Isle Royale National Park.

Aims: We investigated the presence of SARS-CoV-2 in free-ranging wildlife populations in Northeastern Minnesota on the Grand Portage Indian Reservation and Isle Royale National Park.

Methods And Results: One hundred twenty nasal samples were collected from white-tailed deer, moose, grey wolves and black bears monitored for conservation efforts during 2022-2023. Samples were tested for viral RNA by RT-qPCR using the CDC N1/N2 primer set.

Behavioral responses of terrestrial mammals to COVID-19 lockdowns.

COVID-19 lockdowns in early 2020 reduced human mobility, providing an opportunity to disentangle its effects on animals from those of landscape modifications. Using GPS data, we compared movements and road avoidance of 2300 terrestrial mammals (43 species) during the lockdowns to the same period in 2019. Individual responses were variable with no change in average movements or road avoidance behavior, likely due to variable lockdown conditions.

Factors influencing lion movements and habitat use in the western Serengeti ecosystem, Tanzania.

Protected areas that restrict human activities can enhance wildlife habitat quality. Efficacy of protected areas can be improved with increased protection from illegal activities and presence of buffer protected areas that surround a core protected area. Habitat value of protected areas also can be affected by seasonal variation in anthropogenic pressures.

White-tailed deer exploit temporal refuge from multi-predator and human risks on roads.

Although most prey have multiple predator species, few studies have quantified how prey respond to the temporal niches of multiple predators which pose different levels of danger. For example, intraspecific variation in diel activity allows white-tailed deer () to reduce fawn activity overlap with coyotes ) but finding safe times of day may be more difficult for fawns in a multi-predator context. We hypothesized that within a multi-predator system, deer would allocate antipredation behavior optimally based on combined mortality risk from multiple sources, which would vary depending on fawn presence.

Quantifying anthropogenic wolf mortality in relation to hunting regulations and landscape attributes across North America.

Understanding the types and magnitude of human-caused mortality is essential for maintaining viable large carnivore populations. We used a database of cause-specific mortality to examine how hunting regulations and landscape configurations influenced human-caused mortality of North American gray wolves (). Our dataset included 21 studies that monitored the fates of 3564 wolves and reported 1442 mortalities.

Variable effects of wolves on niche breadth and density of intraguild competitors.

The parallel niche release hypothesis (PNR) indicates that reduced competition with dominant competitors results in greater density and niche breadth of subordinate competitors and which may support an adaptive advantage.We assessed support for the PNR by evaluating relationships between variation in niche breadth and intra- and interspecific density (an index of competition) of wolves () coyotes (), and bobcats ().We estimated population density (wolf track surveys, coyote howl surveys, and bobcat hair snare surveys) and variability in space use (50% core autocorrelated kernel density home range estimators), temporal activity (hourly and overnight speed), and dietary (isotopic δC and δN) niche breadth of each species across three areas of varying wolf density in the Upper Peninsula of Michigan, USA, 2010-2019.

Marginal support for a trophic cascade among sympatric canids in peripheral wolf range.

Trophic cascades reportedly structure ecological communities through indirect species interactions. Though the predator-herbivore-autotroph relationship has received much attention, mechanistic evidence supporting intraguild trophic cascades is rare. We established 348 remote camera sites (1 August-5 September 2019) across seven study areas of varying wolf (Canis lupus) density including one study area where wolves were absent in northern Michigan, USA.

American martens use vigilance and short-term avoidance to navigate a landscape of fear from fishers at artificial scavenging sites.

Where two sympatric species compete for the same resource and one species is dominant, there is potential for the subordinate species to be affected through interference competition or energetic costs of avoiding predation. Fishers (Pekania pennanti) and American martens (Martes americana) often have high niche overlap, but fishers are considered dominant and potentially limiting to martens. We observed presence and vigilance of fishers and martens at winter carcass sites using remote cameras in Michigan, USA, to test the hypothesis that interference competition from fishers creates a landscape of fear for martens.

SNAPSHOT USA 2019: a coordinated national camera trap survey of the United States.

With the accelerating pace of global change, it is imperative that we obtain rapid inventories of the status and distribution of wildlife for ecological inferences and conservation planning. To address this challenge, we launched the SNAPSHOT USA project, a collaborative survey of terrestrial wildlife populations using camera traps across the United States. For our first annual survey, we compiled data across all 50 states during a 14-week period (17 August-24 November of 2019).

Interference competition between wolves and coyotes during variable prey abundance.

Interference competition occurs when two species have similar resource requirements and one species is dominant and can suppress or exclude the subordinate species. Wolves () and coyotes () are sympatric across much of their range in North America where white-tailed deer () can be an important prey species. We assessed the extent of niche overlap between wolves and coyotes using activity, diet, and space use as evidence for interference competition during three periods related to the availability of white-tailed deer fawns in the Upper Great Lakes region of the USA.

Influence of body mass and environmental conditions on winter mortality risk of a northern ungulate: Evidence for a late-winter survival bottleneck.

A relationship between winter weather and survival of northern ungulates has long been established, yet the possible roles of biological (e.g., nutritional status) and environmental (e.