Biology subjects

Vucetich, J. A.

Publications and source records attributed to Vucetich, J. A..

4 recordsLinked to original sources

bioRxiv2023

Attitudes Toward Cougar Restoration in Seven Eastern States

EXECUTIVE SUMMARYO_ST_ABSBACKGROUNDC_ST_ABSCougars (Puma concolor), also known as mountain lions, pumas, catamounts, and Florida panthers, once ranged widely throughout the United States (McCollough, 2011). Following intensive human persecution, anthropogenic-driven habitat loss, and unrestricted hunting of the prey species upon which cougars depend, populations were extirpated from much of the country (Cardoza & Langolis, 2002). In the northeastern U.S. specifically, cougars were functionally extinct by the early 1900s. Recent research assessing potential habitat for cougars suggests numerous areas exist to restore the species throughout portions of their historic eastern range (Winkel et al., 2022; Yovovich et al., 2023). But are the humans inhabiting this region today supportive of cougar restoration? STUDY OBJECTIVESThe primary goal of this study was to make a preliminary assessment of support for cougar restoration at the state level in several states deemed to have substantial habitat for cougars (i.e., Maine, Massachusetts, New Hampshire, New York, Pennsylvania, Vermont, and West Virginia). Additionally, we sought to identify individual-level correlates of support for, and opposition to, cougar restoration. STUDY FINDINGSResults from an online survey of residents of seven eastern states with potential cougar habitat (n=2756) suggest that support for cougar restoration is much higher than opposition to cougar restoration. Ratios of strong support to strong opposition range from approximately 4:1 to 13:1. Maine has the highest ratio of strong support to strong opposition at 13:1, indicating that for every one person opposing cougar restoration in the state, we can expect 13 people to support it. Vermont and New Hampshire have the second highest ratio of strong support to strong opposition at 12:1 each. New York and Massachusetts have the second lowest ratio of strong support to strong opposition, at 5:1 each. West Virginia and Pennsylvania have the lowest ratio of strong support to strong opposition with ratios of 4:1, indicating that for every one person opposing cougar restoration in these states, we can expect 4 people to support it. Results also reveal that states with the lowest ratio of strong support to strong opposition tend to have the highest proportion of respondents expressing neutrality toward the idea of restoration. At the individual-level, support for cougar restoration was higher among men, respondents identifying "strongly" or "very strongly" as a hunter or a conservationist, those with mutualist wildlife value orientations, urban residents, and respondents identifying as politically liberal. IMPLICATIONSGiven the current structure of wildlife management in the U.S., efforts to restore cougars throughout significant portions of their historic range will depend in large part on actions taken by state wildlife management agencies. Finding support for cougar restoration among many of the constituents for whom state wildlife agencies are expected to operate on behalf of - including both hunters and conservationists - this study offers valuable insights regarding the social feasibility of restoring cougars to the eastern U.S. Importantly, while a majority of respondents were supportive of cougar restoration, a considerable portion of the population in each state expressed neutrality toward the idea of cougar restoration. Extant research from the behavioral sciences suggests these individuals may be more likely to change their attitudes toward cougar restoration in response to new information. Whether any such change would result in greater support or greater opposition toward cougar restoration is likely dependent on several factors, including the way in which information regarding the potential risks and benefits of the species is presented (Slagle et al., 2013), as well as the source/messenger from which new information is provided (e.g., Fielding et al., 2020). COVER IMAGEWord cloud produced from survey participant responses to free association when they think of cougars.

scientific communication and education↗

bioRxiv2022

Genomic underpinnings of population persistence in Isle Royale moose

Island ecosystems provide models to assess the impacts of isolation on population persistence. However, most studies of persistence have focused on a single species, without comparisons to other organisms they interact with in the ecosystem. The simple predator-prey system of moose and gray wolves on Isle Royale provides allows a direct contrast of genetic variation in a prey species with their natural predator. Wolves on Isle Royale exhibited signs of severe inbreeding depression, which nearly drove the population to extinction in 2019. In the relative absence of wolves, the moose population has thrived and exhibits no obvious signs of inbreeding depression despite being isolated for [~]120 years and having low genetic diversity. Here, we examine the genomic underpinnings of population persistence in the Isle Royale moose population. We document high levels of inbreeding in the population, roughly as high as the wolf population at the time of its decline. However, inbreeding in the moose population manifests in the form of intermediate-length runs of homozygosity indicative of gradual inbreeding, contrasting with the severe recent inbreeding observed in the wolf population. Using simulations, we demonstrate that this more gradual inbreeding in the moose population has resulted in an estimated 50% purging of the inbreeding load, helping to explain the continued persistence of the population. However, we also document notable increases in genetic load, which could eventually threaten population viability over the long term. Finally, we document low diversity in mainland North American moose populations due to a severe founder event occurring near the end of the Holocene. Overall, our results demonstrate a complex relationship between inbreeding, genetic diversity, and population viability that highlights the importance of maintaining isolated populations at moderate size to avert extinction from genetic factors. Significance statementIsolated wildlife populations face a high risk of extinction due in part to the deleterious consequences of inbreeding. Whether purifying natural selection can overcome these negative impacts by "purging" harmful recessive mutations is a topic of active debate. We characterized the extent of purging in an isolated moose population. Our results demonstrate signatures of gradual inbreeding in the population, ideal circumstances to facilitate purging. Using simulations, we demonstrate substantial potential for purging in the population, though we also show that fitness is reduced by small population size and inbreeding. Our findings provide insight into the mechanisms enabling persistence in isolated populations, with implications for conserving the growing number of isolated populations worldwide.

evolutionary biology↗

bioRxiv2019

Tooth fracture frequency in gray wolves reflects prey availability

Exceptionally high rates of tooth fracture in large Pleistocene carnivorans imply intensified interspecific competition, given that tooth fracture rises with increased bone consumption, a behavior that likely occurs when prey are difficult to acquire. To assess the link between prey availability and dental attrition, we documented dental fracture rates over decades among three well-studied populations of extant gray wolves that differed in prey:predator ratio and levels of carcass utilization. When prey:predator ratios declined, kills were more fully consumed, and rates of tooth fracture more than doubled. This supports tooth fracture frequency as a relative measure of the difficulty of acquiring prey, and reveals a rapid response to diminished food levels in large carnivores despite risks of infection and reduced fitness due to dental injuries. More broadly, large carnivore tooth fracture frequency likely reflects energetic stress, an aspect of predator success that is challenging to quantify in wild populations.

ecology↗

bioRxiv2018

Genomic signatures of extensive inbreeding in Isle Royale wolves, a population on the threshold of extinction

The observation that small, isolated populations often suffer reduced fitness as a result of inbreeding depression has guided conservation theory and practice for decades. However, investigating the genome-wide dynamics associated with inbreeding depression in natural populations is only now feasible with relatively inexpensive sequencing technology and annotated reference genomes. To characterize the genome-wide effects of intense inbreeding and isolation, we sequenced complete genomes from an iconic inbred population, the gray wolves (Canis lupus) of Isle Royale. Through comparison with other wolf genomes from a variety of demographic histories, we found that Isle Royale wolf genomes contain extensive runs of homozygosity, but neither the overall level of heterozygosity nor the number of deleterious variants per genome were reliable predictors of inbreeding depression. These findings are consistent with the hypothesis that severe inbreeding depression results from increased homozygosity of strongly deleterious recessive mutations, which are more prevalent in historically large source populations. Our results have particular relevance in light of the recently proposed reintroduction of wolves to Isle Royale, as well as broader implications for management of genetic variation in the fragmented landscape of the modern world.

evolutionary biology↗