Natural Resources Management and Policy Commons^™

Discovery Of A Novel Invasive Rodent Species On Wake Atoll With A Desert Southwest Usa Origin, Antoinette J. Piaggio, Eric Lanners, Daniel R. Taylor, Aaron B. Shiels, Marjorie Matocq, John Eisemann

United States Department of Agriculture Wildlife Services: Staff Publications

Invasive species, particularly omnivorous rodents, have damaged island ecosystems around the world. The unique flora and fauna of island systems have typically not evolved with omnivorous rodents and are heavily impacted by their introduction. Wake Atoll of the southern Pacific Ocean is a 707-hectare coral island complex of three islands managed by the United States Department of Defense (DoD). DoD restricts civilian access to the atoll but aircraft and seacraft regularly visit the island to transport military equipment and to sustain the year-round military and contractor personnel stationed on the atoll. Wake Atoll had been invaded by Rattus rattus complex …

Efficacy Of Gonacon Fertility Control Against Prairie Dogs And Potential For Uses On Other Rodent Species, Aaron B. Shiels, Emily W. Ruell, Jason E. Bruemmer

United States Department of Agriculture Wildlife Services: Staff Publications

Use of a contraceptive (i.e., fertility control) is attractive for rodent management where lethal control is unwanted. Although population reduction is generally unachievable with small-scale, short-term contraceptive use, reduced juvenile recruitment is achievable. The injectable immunocontraceptive vaccine GonaCon (active ingredient: gonadotropin releasing hormone [GnRH]) was registered in 2022 by the United States Environmental Protection Agency (EPA) for controlling fertility of female prairie dogs (Cynomys, a type of ground squirrel) in urban/suburban settings. Here we: 1) describe past research, including a replicated field study in Colorado (GonaCon treatment vs. control sites) testing efficacy of GonaCon in prairie dogs, which …

Agricultural And Ecological Resources Safeguarded By The Prevention Of Wild Pig Population Expansion, Colin Jareb, Kim M. Pepin, Ryan S. Miller, Stephanie A. Shwiff, Sophie C. Mckee

United States Department of Agriculture Wildlife Services: Staff Publications

Wild pigs (Sus scrofa) are one of the most destructive invasive species in the United States, known for causing extensive damage to agricultural commodities, natural resources, and property, and for transmitting diseases to livestock. Following the establishment of the National Feral Swine Damage Management Program (NFSDMP) in 2014, the expansion of wild pig populations has been successfully slowed. This paper combines two modeling approaches across eight separate models to characterize the expansion of wild pig populations in the absence of intervention by the NFSDMP and forecasts the value of a subset of resources safeguarded from the threat of …

Oral Rabies Vaccination Of Raccoons (Procyon Lotor) Across A Development Intensity Gradient In Burlington, Vermont, Usa, 2015–2017, Emily M. Beasley, Kathleen M. Nelson, Dennis Slate, Amy T. Gilbert, Frederick E. Pogmore, Richard B. Chipman, Amy J. Davis

United States Department of Agriculture Wildlife Services: Staff Publications

Management of the raccoon rabies virus variant in North America is conducted primarily using oral rabies vaccination (ORV). When a sufficient proportion of the population is vaccinated (60%), rabies transmission can be eliminated. To date, ORV programs have successfully controlled and eliminated raccoon rabies in rural areas, but there has been less success in urban areas. We studied the proportions of rabies virus neutralizing antibodies (RVNA) in a raccoon (Procyon lotor) population during a 3-year ORV trial in developed areas of Burlington, Vermont, United States. We used a modified N-mixture model to estimate raccoon abundance, RVNA seroprevalence, and …

Ethyl-Iophenoxic Acid As A Serum Marker For Oral Baiting Of Tasmanian Devils, Ruth Pye, David Nichols, Sally A. Nofs, Amy T. Gilbert, Andrew S. Flies

United States Department of Agriculture Wildlife Services: Staff Publications

Oral baits containing vaccines, medicants or toxicants have been delivered to a broad range of wildlife species to protect against or treat disease, or suppress populations. Ethyl-Iophenoxic acid (Et-IPA) is used as a biomarker to determine oral bait consumption by wildlife species to assess and refine baiting strategies. Et-IPA is a persistent biomarker in many eutherian mammal species but not in the two marsupial species, swamp wallaby (Wallabia bicolor) and brushtail possum (Trichosurus vulpecula), tested to date. Et-IPA has not previously been evaluated in carnivorous marsupials. The Tasmanian devil (Sarcophilus harrisii), the largest extant …

Estimating Landscape Spread Of A Low-Prevalence Disease Using Multiple Surveillance Methods, Abigail Feuka, Aakash Pandey, Melinda Cosgrove, Megan Moriarty, Anthony Duffiney, Henry Campa Iii, Kurt C. Vercuteren, Kimberly M. Pepin

United States Department of Agriculture Wildlife Services: Staff Publications

1. Diseases occurring at low prevalence in free-ranging wildlife can be difficult to study and predict at a landscape scale. This problem is compounded by imperfect pathogen detection.

2. We used data from multiple surveillance methods to determine factors influencing spread of a low-prevalence disease, bovine tuberculosis (bTB), among white-tailed deer (Odocoileus virginianus) in a bTB endemic area over a 10-year period. We fit dynamic occupancy models to predict spatial spread of bTB through a county in Michigan, USA, within the bTB endemic area, while accounting for imperfect detection and a suite of ecological processes potentially driving bTB …

Effects Of The Immunocontraceptive Gonacon On Pregnancy In Brucella-Seropositive American Bison (Bison Bison), Rebecca K. Frey, Morgan E. Wehtje, Pauline Nol, Patrick R. Clarke, Jack C. Rhyan, Matthew P. Mccollum, Lowell A. Miller, Douglas C. Eckery

United States Department of Agriculture Wildlife Services: Staff Publications

The purpose of this study was to determine if the number of pregnancies in naturally infected Brucella abortus-positive bison (Bison bison) cows would be reduced over a period of 5 yr after one treatment with 3000 mg gonadotropin-releasing hormone immunocontraceptive (GonaCon) compared to a similar group of naturally infected B. abortus-positive bison cows not treated with GonaCon. In each of the 5 yr, GonaCon-treated cows produced fewer offspring in relation to number of cows than the nontreated cows. Fisher’s Exact test comparing offspring produced during the first reproductive season showed a significant difference between the …

Efficacy Of X-Ray Phytosanitary Irradiation On The Infectivity And Reproduction Of Angiostrongylus Cantonensis In Experimentally Infected Rats, Susan I. Jarvi, Lisa M. Kaluna, Steven C. Hess, Lindsey Hamilton, Carmen Antaky, Robert T. Sugihara, Israel L. Leinbach, Yaeko Tagami, Argon Steel, Kathleen Howe, Steven Jacquier, Forrest Cookman, Jocelyn Diaz, John Jacob, Peter Follett

United States Department of Agriculture Wildlife Services: Staff Publications

Angiostrongylus cantonensis is a globally distributed nematode and the leading cause of eosinophilic meningitis in humans. As a global hotspot for this disease, Hawaii’s agricultural exports may be contributing to the spread of A. cantonensis. Phytosanitary irradiation doses of 150 or 400 Gy provide quarantine security against multiple insect pests. We evaluated the in vitro and in vivo effects of phytosanitary irradiation on infectious, third-stage A. cantonensis juveniles. In vitro experiments directly exposed juveniles to irradiation doses ranging from 200 to 1,000 Gy. Results showed low mortality and no dose response across all treatments 27 days post-irradiation. …

The Ltar Grazing Land Common Experiment At Platte River High Plains Aquifer, M. Khorchani, M. Schmer, A. Freidenreich, T. Awada, G. Birru, S. Christofferson, R. Drijber, G. Erickson, V. Jin, R. Mcdermott, A. Suyker, A. Watson, B. Woodbury, Y. Xiong, J. Hiller, X. Sun, L. Li

School of Natural Resources: Faculty Publications

The Long-Term Agroecosystem Research (LTAR) network of the United States Department of Agriculture (USDA) consists presently of 18 sites within the contiguous United States that are managed by the Agricultural Research Service (ARS) and its partners. The LTAR network focuses on developing national strategies for more efficient, resilient, and profitable agricultural production systems, improved environmental quality, and enhanced rural prosperity. The Platte River High Plains Aquifer (PRHPA) LTAR site is managed jointly by the University of Nebraska–Lincoln (UNL) and USDA-ARS and is one of the LTAR sites that conduct research on both integrated cropping and grazing systems. The PRHPA region …

The Ltar Cropland Common Experiment At Platte River/High Plains Aquifer, Ariel Freidenreich, Marty R. Schmer, Makki Khorchani, Girma Birru, Virginia L. Jin, Tala Awada, Rhae A. Drijber, Andrew Suyker, S. Carolina Córdova, Tyler Smith, Tim Kettler, Sandra Christofferson, Xiangmin Sun, Lidong Li

School of Natural Resources: Faculty Publications

The Platte River/High Plains Aquifer (PR/HPA) region is characterized by cropland, pastures, and grasslands that are faced with changing climatic conditions and agricultural intensification. The PR/HPA Long-Term Agroecosystem Research (LTAR) site is located in Eastern Nebraska with the goal of improving resilience, sustainability, and profitability of agroecosystems through enhancing ecosystem services and environmental quality, developing strategies for efficient agricultural production, and mitigating and adapting to climate change. To meet this goal, a common experiment and five ancillary experiments have been developed to evaluate prevailing regional practices in grain crop production systems compared to alternative practices in rain-fed and irrigated systems. …

Recent Beak Evolution In North American Starlings After Invasion, Julia M. Zichello, Shelagh T. Deliberto, Paul Shrewsbury, Agnieszka A. Pierwola, Scott J. Werner

United States Department of Agriculture Wildlife Services: Staff Publications

European starlings are one of the most abundant and problematic avian invaders in the world. From their native range across Eurasia and North Africa, they have been introduced to every continent except Antarctica. In 160 years, starlings have expanded into different environments throughout the world, making them a powerful model for understanding rapid evolutionary change and adaptive plasticity. Here, we investigate their spatiotemporal morphological variation in North America and the native range. Our dataset includes 1,217 specimens; a combination of historical museum skins and modern birds. Beak length in the native range has remained unchanged during the past 206 years, …

Assessing The Efficiency Of Local Rabies Vaccination Strategies For Raccoons (Procyon Lotor) In An Urban Setting, Guillaume Bastille-Rousseau, Nicole T. Gorman, Katherine M. Mcclure, Larissa Nituch, Tore Buchanan, Richard B. Chipman, Amy T. Gilbert, Kim M. Pepin

United States Department of Agriculture Wildlife Services: Staff Publications

Raccoon rabies virus (RRV) has been managed using multiple vaccination strategies, including oral rabies vaccination and trap-vaccinate-release (TVR). Identifying a rabies vaccination strategy for an area is a nontrivial task. Vaccination strategies differ in the amount of effort and monetary costs required to achieve a particular level of vaccine seroprevalence (efficiency). Simulating host movement relative to different vaccination strategies in silico can provide a useful tool for exploring the efficiency of different vaccination strategies. We refined a previously developed individual-based model of raccoon movement to evaluate vaccination strategies for urban Hamilton, Ontario, Canada. We combined different oral rabies vaccination baiting …

Use Of Rhodamine B As A Biomarker In A Simulated Oral Vaccine Deployment Against Bovine Tuberculosis In White-Tailed Deer, David Dressel, Kurt Vercauteren, Michael Lavelle, Nathan P. Snow, Henry Campa Iii

United States Department of Agriculture Wildlife Services: Staff Publications

Introduction Free-ranging white-tailed deer (Odocoileus virginianus) in northeastern lower Michigan, United States are a self-sustaining reservoir for bovine tuberculosis (bTB). Farm mitigation practices, baiting bans, and antlerless deer harvests have been ineffective in eliminating bTB in white-tailed deer and risks to cattle. The apparent prevalence has remained relatively constant in deer, prompting interest among wildlife researchers, managers, and veterinarians for an effective means of vaccinating deer against bTB. The commonly used human vaccine for bTB, Bacillus Calmette Guerin (BCG), is the primary candidate with oral delivery being the logical means for vaccinating deer.

Materials and methods We developed …

Identifying Priority Mitigation Areas For Human–Osprey Conflict, Natasha K. Murphy, Melanie R. Boudreau, Brian S. Dorr, Kate Slankard, Scott A. Rush

United States Department of Agriculture Wildlife Services: Staff Publications

Raptor nests on human‐built structures represent a significant source of conflict, as they can result in bird mortality, fires, or power outages due to falling nest materials or animals connecting with energized conductors. Power companies typically try to mitigate these conflicts to avoid service disruptions. Performing mitigation measures across all potentially problematic power infrastructure is generally not a practical solution given logistical, time, or budgetary constraints. Therefore, there is a need for quantitative, landscapescale tools to identify conflict risk and prioritize mitigation. We examined the influence of habitat and transmission infrastructure distribution on the potential risk of osprey (Pandion …

Efficacy Of An Inflatable Deterrent For Reducing New World Vulture Human‑Wildlife Conflict, Bryan M. Kluever, Betsy A. Evans, Noah M. Osterhoudt, Eric A. Tillman

United States Department of Agriculture Wildlife Services: Staff Publications

Increasing urbanization coupled with spatial expansion and numerical increase of New World vulture populations has engendered a rise in human-vulture conflict, creating a need for effective tools to mitigate vulture-related damage. Visual frightening devices that mimic the presence of human or other predators can be employed in human-vulture conflict scenarios to increase perceived risk by the pest species, thereby eliciting an antipredator behavioral response, such as fleeing. One visual frightening device, inflatable scarecrows, recently proved effective at reducing passerine attendance at feral swine feeders, but their effectiveness when directed at other species and conflict scenarios has varied. Our primary objective …

Probabilistic Genetic Identification Of Wild Boar Hybridization To Support Control Of Invasive Wild Pigs (Sus Scrofa), Timothy J. Smyser, Peter Pfaffelhuber, Rachael M. Giglio, Matthew G. Desaix, Amy J. Davis, Courtney F. Bowden, Michael A. Tabak, Arianna Manunza, Valentin Adrian Bâlteanu, Marcel Amills, Laura Iacolina, Pamela Walker, Carl Lessard, Antoinette J. Piaggio

United States Department of Agriculture Wildlife Services: Staff Publications

The rapid expansion of wild pigs (Sus scrofa) throughout the United States has been fueled by unlawful introductions, with invasive populations causing extensive crop losses, damaging native ecosystems, and serving as a reservoir for disease. Multiple states have passed laws prohibiting the possession or transport of wild pigs. However, genetic and phenotypic similarities between domestic pigs and invasive wild pigs—which overwhelmingly represent domestic pig and wild boar hybrids—pose a challenge for the enforcement of such regulations. We sought to exploit wild boar ancestry as a common attribute among the vast majority of invasive wild pigs as a means …

Effects Of Pregnancy Prevention On Brucella Abortus Shedding In American Bison (Bison Bison), Pauline Nol, Rebecca Frey, Morgan Wehtje, Jack C. Rhyan, Patrick Ryan Clarke, Matthew Mccollum, Christine Quance, Douglas C. Eckery, Suelee Robbe-Austerman

United States Department of Agriculture Wildlife Services: Staff Publications

Products of parturition are the predominant source of Brucella abortus for transmission in bison (Bison bison). Our objective was to assess whether preventing pregnancy in Brucella-seropositive bison reduced B. abortus shedding. Brucella-seropositive and -seronegative bison from Yellowstone National Park, Wyoming, USA were used in a replicated experiment. Each of two replicates (rep1, rep2) included a group of seropositive females treated with a single dose of gonadotropin-releasing hormone-based immunocontraceptive (Treatment rep1, n = 15; Treatment rep2, n = 20) and an untreated group (Control rep1, n = 14; Control rep2, …

Internal And External Factors Affect Pair Mate Proximity In Captive Coyotes, Canis Latrans, Alexandra Turano, Stacey P. Brummer, Jeffrey T. Schultz, Julie Young, Sara M. Freeman

United States Department of Agriculture Wildlife Services: Staff Publications

No abstract provided.

Toxoplasma Gondii Survey In Waterfowl And Gulls From Eight Usa States, Sawsan Ammar, Tania J. Dawant, Janetta Kelly, Graham Hickling, Justin Brown, Kyle R. Van Why, Rebecca Poulson, Chunlei Su, Richard W. Gerhold Jr.

United States Department of Agriculture Wildlife Services: Staff Publications

Sera from 391 waterbirds from eight USA states were tested for Toxoplasma gondii antibodies using the modified agglutination test. Fifteen different waterbird species (26.6%; n = 104) were seropositive. Of the adults, 25.4% (n = 52) showed a significantly higher T. gondii seroprevalence compared with juveniles (13.4%; n = 17); however, sex was not a significant factor.

Increased Bat Activity At Urban Water Sources: Implications For Cross-Species Transmission Of Bat Rabies To Mesocarnivores, Lias A. Hastings, Carol L. Chambers, David L. Bergman, Tad C. Theimer

United States Department of Agriculture Wildlife Services: Staff Publications

We examined the potential for urban water sources, specifically golf course ponds, to act as centers for rabies transmission from bats to mesocarnivores in the arid southwestern United States where surface water is often limited. Because residential housing can act as den and roost sites for both mesocarnivores and bats, we also examined the effect of housing density around water sources on activity. Using ultrasonic acoustic recorders to assess bat activity and camera traps to estimate mesocarnivore activity, we compared 14 pairs of wet and dry locations over two years by surveying twice during the summer, once prior to summer …

Experimental Assessment Of Laser Scarecrows For Reducing Avian Damage To Sweet Corn, Sean T. Manz, Kathryn E. Sieving, Rebecca N. Brown, Page E. Klug, Bryan M. Kluever

United States Department of Agriculture Wildlife Services: Staff Publications

Background

Birds damage crops, costing millions of dollars annually, and growers utilize a variety of lethal and nonlethal deterrents in an attempt to reduce crop damage by birds. We experimentally tested laser scarecrows for their effectiveness at reducing sweet corn (Zea mays) damage. We presented 18 captive flocks of free-flying European starlings (Sturnus vulgaris) with fresh sweet corn ears distributed on two plots where laser and control treatments were alternated each day and allowed each flock to forage over 5 days. In 16 trials, fresh sweet corn ears were mounted on wooden sticks distributed from 0 …

Unraveling Parasite Identification In Invasive And Endangered Squirrel Species: Potential For Parasite Spillover, Deandra Jones, Patricia S. Stock, Emilie Lefoulon, Maria V. Mazzamuto, W. Eugene Hall, David L. Bergman, John L. Kaprowski

United States Department of Agriculture Wildlife Services: Staff Publications

Invasive species can impact ecosystem health by introducing parasites during their establishment in new areas. However, the dynamics of parasite loads between invasive and native species remain poorly understood. In the 1940s, Abert’s squirrels (Sciurus aberti) were introduced to the Pinaleño Mountains in southeastern Arizona where they now co-occur with endemic endangered Mt. Graham red squirrels (Tamiasciurus fremonti grahamensis). The study aimed to identify and quantify parasites in both Abert’s and Mt. Graham red squirrels, with a focus on investigating possible parasite spillover between these two species and examining how host-related factors affect parasite presence. PCR …

Coyotes In The Great Basin Desert Do Not Exhibit A Spatial Response Following The Removal Of Anthropogenic Water Sources, Nadine A. Pershyn, Eric M. Gese, Erica F. Stuber, Bryan M. Kluever

United States Department of Agriculture Wildlife Services: Staff Publications

Coyote (Canis latrans) range expansion into desert ecosystems has highlighted the role of anthropogenic water sources in arid ecosystems. Despite hypotheses that additional water facilitated this expansion, previous studies reported that coyotes did not exhibit a spatial or dietary response to removal of anthropogenic water. We used GPS data to examine if coyotes responded to water removal at a finer spatial scale than previously investigated. Our integrated step selection analysis did not find evidence that coyotes adjusted their distance to water following water removal. Vegetation was an important factor in habitat selection of coyotes, with riparian and agricultural …

Frequency And Vehicle Damage Costs Of Wild Pig‑Vehicle Collisions In The United States, 2015–2022, Sophie C. Mckee, Jeremiah L. Psiropoulos, John J. Mayer

United States Department of Agriculture Wildlife Services: Staff Publications

The increasing frequency of wildlife-vehicle collisions (WVCs) is a globally recognized problem that can severely impact both the animals and humans involved in these accidents. Introduced wild pigs (Sus scrofa) have been present in various parts of the USA for centuries, but no study on wild pig-vehicle collisions (WPVCs) has been conducted on a national scale for the USA Using data provided by State Farm, we derived the number of vehicle collisions with wild pigs by state in the USA over the 2015–2022 period and the associated vehicle damage costs. In 2022, we estimated that a total of …

An Estimate Of The Marginal Annual Economic Contribution Of Wild-Pig Hunting In Texas, Sophie C. Mckee, Keith M. Carlisle, John Tomeček, Stephanie A. Shwiff, Rachael Connally, Maureen Frank, Mike Bodenchuk, Nicole Didero

United States Department of Agriculture Wildlife Services: Staff Publications

Context

Wild-pig (Sus scrofa) hunting is a culturally significant recreational and commercial activity in Texas, but the overall impacts are contested. Except for one 1980s study, there has been no research to formally quantify any economic benefits of wild-pig hunting in Texas, which is an important component for weighing the costs and benefits of wild-pig presence in the state.

Aims and methods

To fill that research gap, we surveyed a sample of resident and non-resident 2018–2019 hunting-license holders in Texas about various topics related to their wild-pig hunting activities, including expenditures

Key results

On the basis of the …

Use Of Nest Boxes By European Starlings (Sturnus Vulgaris): Effects Of Perceived Nest Predation Risk, Bradley F. Blackwell, Morgan B. Pfeiffer, Joshua L. Hoblet, Bruce N. Buckingham

United States Department of Agriculture Wildlife Services: Staff Publications

The European starling (Sturnus vulgaris) has expanded beyond its native Eurasian range, exploiting both natural cavities and human structures for nesting. We hypothesized that starling exposure to enhanced risk of nest predation at nest boxes (surrogates for nest sites in other structures), due to predator access, would negatively affect occupancy (establishment of a nest and ≥ 1 egg) and subsequent nest success. We also hypothesized that starlings would show no distinction in occupancy between nest boxes relative to the presence/absence of old nest material (i.e., material from the previous season), conditions that can contribute to nest predation risk. …

Steps Towards Operationalizing One Health Approaches, Kim M. Pepin, Keith M. Carlisle, Dean Anderson, Michael G. Baker, Richard B. Chipman, Jackie Benschop, Nigel P. French, Suzie Greenhalgh, Scott Mcdougall, Petra Muellner, Emil Murphy, Dion R. J. Neale, Michael J. Plank, David T. S. Hayman

United States Department of Agriculture Wildlife Services: Staff Publications

One Health recognizes the health of humans, agriculture, wildlife, and the environment are interrelated. The concept has been embraced by international health and environmental authorities such as WHO, WOAH, FAO, and UNEP, but One Health approaches have been more practiced by researchers than national or international authorities. To identify priorities for operationalizing One Health beyond research contexts, we conducted 41 semi-structured interviews with professionals across One Health sectors (public health, environment, agriculture, wildlife) and institutional contexts, who focus on national-scale and international applications. We identify important challenges, solutions, and priorities for delivering the One Health agenda through government action. Participants …

Discrimination Among Similarly Colored Goose Species In Federal Harvest Surveys, Joshua L. Dooley, Paul F. Doherty Jr., David L. Otis, Gary C. White, Daniel R. Taylor, Doreen L. Griffin, Syephen C. Chandler, Stephanie M. Catino, Kathy K. Fleming, Robert V. Raftovich, Antoinette J. Piaggio

United States Department of Agriculture Wildlife Services: Staff Publications

Each year in the United States, fall‐winter (sport) harvests of goose species are estimated from federal surveys coordinated by the United States Fish and Wildlife Service, including the Migratory Bird Harvest Survey to estimate total goose harvest and the Parts Collection Survey (PCS) to estimate the species and age composition. For the PCS, randomly selected hunters collect tail and wing feathers of each goose shot during the hunting season, and then biologists determine the age class and species of each sample at organized events (Wingbees) in each of the 4 flyways (Pacific, Central, Mississippi, and Atlantic). For similarly colored goose …

Population Growth Rates Of Pronghorn: Influence Of Temporally And Spatially Explicit Conditions, Density Dependence, And Scale, Eric M. Gese, Cole A. Bleke, Shane B. Roberts, Paul Atwood, Patricia A. Terletzky

United States Department of Agriculture Wildlife Services: Staff Publications

Density-independent and density-dependent population regulation has long been a subject of investigation. We examined density-dependent and density-independent factors on growth rates of pronghorn (Antilocapra americana (Ord, 1815)) using a retrospective analysis of population survey data. Across Idaho, we found that as the proportion of the subpopulation harvested the previous year increased, growth rates increased. Similarly, as fawn recruitment increased, growth rates increased. We also found when the growth rate in the previous year increased, the growth rate the subsequent year decreased. When subpopulations were examined independently, we found that in a low-elevation desert subpopulation, growth rates were influenced by …

Effects Of Lethal Management On Gray Wolf Pack Persistence And Reproduction In Wisconsin, Usa, Alejandra Zubiria Perez, Kenneth F. Kellner, David M. Macfarland, Jennifer L. Price Tack, David B. Ruid, Glenn E. Stauffer, Jerold L. Belant

United States Department of Agriculture Wildlife Services: Staff Publications

Direct human-caused mortality accounts for about half of all large mammal mortality in North America. For social species like gray wolves (Canis lupus), the death of pack members can disrupt pack structure and cause pack dissolution, and mortality of breeding adults or wolves during reproduction and pup-rearing can decrease pup recruitment. We estimated minimum and maximum probability of wolf pack persistence in Wisconsin, USA, during biological years (15 April–14 April) 2011–2019 and evaluated the influence of pack size and legal harvest mortality on pack persistence during 2012–2014. Harvests comprised 75–161 mortalities within 194 monitored packs during 2012–2014, with …