Characterizing Nontarget Species Use at Bait Sites for White-Tailed Deer

Baiting white-tailed deer (Odocoileus virginianus) has evolved into a controversial issue of wildlife management. During August–September 2012, we established a grid of 64 cameras in the Upper Peninsula of Michigan at sites baited with corn that simulated legal bait sites for white-tailed deer to characterize presence, diversity, and frequency of species use. We detected \u3e20 species of wildlife that visited bait sites. We categorized 3,177 of 11,194 images as independent detections (i.e., species detected \u3e1 hour apart). White-tailed deer had the greatest detection rate (47%), but overall detections of nontarget species was slightly greater (53%). Most frequent nontarget species detected were northern raccoons (Procyon lotor) and American black bears (Ursus americanus). Wildlife officials should consider the potential effects of baiting on species’ ecology and the potential for disease transmission that high-use of bait sites by nontarget species present

Foot Injuries in Michigan, USA, Gray Wolves (\u3ci\u3eCanis lupus\u3c/i\u3e), 1992–2014

The range of gray wolves (Canis lupus) in the contiguous US is expanding. Research and monitoring to support population recovery and management often involves capture via foothold traps. A population-level epidemiologic assessment of the effect of trap injuries on wolf survival remains needed to inform management. We describe the baseline rate, type, and severity of foot injuries of wolves born 1992–2013 in Michigan’s Upper Peninsula, evaluate the reliability of field-scoring trap-related injuries, and the effect of injuries on wolf survival. We assessed foot injuries by physical and radiographic exam at postmortem and/or time of capture for 351 wolves using the International Organization for Standardization 10990-5 standard and the effects of injuries, sex, age, previous capture and body condition on survival using proportional hazards regression. We used ordinal regression to evaluate epidemiologic associations between sex, age, previous capture, body condition, cause of death and injury severity. Most wolves (53%) experienced no physically or radiographically discernable foot injuries over their lifetimes. Among those wolves that did experience injuries, 33% scored as mild. Foot injuries had little epidemiologically discernable effect on survival rates. Wolves with higher foot trauma scores did experience an increased risk of dying, but the magnitude of the increase was modest. Most limb injuries occurred below the carpus or tarsus, and scoring upper-limb injuries added little predictive information to population-level epidemiologic measures of survival and injury severity. There was little association between injury severity and cause of death. Based on necropsy exams, previous trap injuries likely contributed to death in only four wolves (1.1%). Our results suggest that injuries resulting from foothold traps are unlikely to be a limiting factor in recovery and ongoing survival of the Michigan gray wolf population

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. However, under strict lockdowns 10-day 95th percentile displacements increased by 73%, suggesting increased landscape permeability. Animals' 1-hour 95th percentile displacements declined by 12% and animals were 36% closer to roads in areas of high human footprint, indicating reduced avoidance during lockdowns. Overall, lockdowns rapidly altered some spatial behaviors, highlighting variable but substantial impacts of human mobility on wildlife worldwide.acceptedVersio

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. However, under strict lockdowns 10-day 95th percentile displacements increased by 73%, suggesting increased landscape permeability. Animals' 1-hour 95th percentile displacements declined by 12% and animals were 36% closer to roads in areas of high human footprint, indicating reduced avoidance during lockdowns. Overall, lockdowns rapidly altered some spatial behaviors, highlighting variable but substantial impacts of human mobility on wildlife worldwide.acceptedVersio

Membrane vesicles, current state-of-the-art: emerging role of extracellular vesicles

Release of membrane vesicles, a process conserved in both prokaryotes and eukaryotes, represents an evolutionary link, and suggests essential functions of a dynamic extracellular vesicular compartment (including exosomes, microparticles or microvesicles and apoptotic bodies). Compelling evidence supports the significance of this compartment in a broad range of physiological and pathological processes. However, classification of membrane vesicles, protocols of their isolation and detection, molecular details of vesicular release, clearance and biological functions are still under intense investigation. Here, we give a comprehensive overview of extracellular vesicles. After discussing the technical pitfalls and potential artifacts of the rapidly emerging field, we compare results from meta-analyses of published proteomic studies on membrane vesicles. We also summarize clinical implications of membrane vesicles. Lessons from this compartment challenge current paradigms concerning the mechanisms of intercellular communication and immune regulation. Furthermore, its clinical implementation may open new perspectives in translational medicine both in diagnostics and therapy

Mammals show faster recovery from capture and tagging in human-disturbed landscapes

Wildlife tagging provides critical insights into animal movement ecology, physiology, and behavior amid global ecosystem changes. However, the stress induced by capture, handling, and tagging can impact post-release locomotion and activity and, consequently, the interpretation of study results. Here, we analyze post-tagging effects on 1585 individuals of 42 terrestrial mammal species using collar-collected GPS and accelerometer data. Species-specific displacements and overall dynamic body acceleration, as a proxy for activity, were assessed over 20 days post-release to quantify disturbance intensity, recovery duration, and speed. Differences were evaluated, considering species-specific traits and the human footprint of the study region. Over 70% of the analyzed species exhibited significant behavioral changes following collaring events. Herbivores traveled farther with variable activity reactions, while omnivores and carnivores were initially less active and mobile. Recovery duration proved brief, with alterations diminishing within 4–7 tracking days for most species. Herbivores, particularly males, showed quicker displacement recovery (4 days) but slower activity recovery (7 days). Individuals in high human footprint areas displayed faster recovery, indicating adaptation to human disturbance. Our findings emphasize the necessity of extending tracking periods beyond 1 week and particular caution in remote study areas or herbivore-focused research, specifically in smaller mammals

SURVIVAL, REPRODUCTION, AND MOVEMENTS OF MOOSE IN THE WESTERN UPPER PENINSULA OF MICHIGAN

Moose were extirpated from the Lower Peninsula of Michigan by the late 1800s. Although it is not clear if moose were extirpated from the Upper Peninsula (UP), the population was at the very least, reduced to a low level by ca 1900. Attempts to re-establish a population of moose in the UP during the mid-1930s failed. The Michigan Department of Natural Resources made a second attempt to reestablish moose by translocating animals from Canada to the western UP in 1985 and 1987. Based on optimistic estimates of survival and reproductive rates and habitat surveys, a population of 1,000 moose was expected by the year 2000. However, aerial surveys conducted in the winters of 1996 and 1997 produced population size estimates that were well below 1,000. To determine possible reasons for the slower than expected population growth, 84 moose were outfitted with radio-collars in the winters of 1999-2001. The survival, reproduction, and movements of these moose and 12 others radio-collared in 1995 were monitored from January 1999-June 2001. Overall, 1999-2001 pregnancy rates averaged 75%. Annual adult survival rate (0.88) was higher than yearling survival rate (0.82). First-year calf survival rate (0.71) was high, relative to highly preyed on populations. Annually, approximately 6% of radio-collared moose, primarily yearlings, dispersed out of the study area. The size of moose home ranges was typical of those found in the deciduous/coniferous ecotone of the upper Great Lakes region. Migratory adult moose had larger annual home ranges than did non migratory adult moose. Low productivity appears to be the likely cause of the slower than predicted population growth. Data from this study can be utilized to facilitate management of moose in the upper Great Lakes region