Coyote removal: can the short-term application of a controversial management tool improve female greater sage-grouse survival or nest success?

Greater sage-grouse Centrocercus urophasianus have declined across western North America, intensifying the need for ecological research that enhances management and conservation goals. Predator–prey interactions can have widespread ecological effects but there is a paucity of information about predator effects on sage-grouse ecology. During a two-year study from 2011–2012, we modified the existing framework designed for predator management to test the effects of coyote Canis latrans removal on female sage-grouse survival and nest success in the Bighorn Basin of Wyoming, USA, where coyotes were found to be the dominant predator. We used VHF radio-telemetry to monitor female survival and locate nests over pre-treatment and treatment breeding seasons, and for one-year post-treatment to the next breeding season. During treatment, we manipulated predator management at three sites to have targeted, non-targeted, and no coyote removal. Female survival remained constant over the nesting period when treatment was applied, and there were little differences between one-year pre- (Š = 0.64, 90% CI = 0.38, 0.90) and one-year post-treatment survival estimates (Š = 0.71, 90% CI = 0.55, 0.87) at the targeted coyote removal site. No differences were detected in the daily survival rates of nests relative to coyote removal. We conclude removing coyotes, the primary predator of nests and adult females identified within this system, did not improve female survival or nest success. However, long-term monitoring is recommended to provide a more robust understanding of this complex relationship

The Tail Wagging the Dog: Positive Attitude Towards Livestock Guarding Dogs Do Not Mitigate Pastoralists’ Opinions of Wolves or Grizzly Bears

While the re-establishment of grizzly bears (Ursus arctos) and wolves (Canis lupus) in the American West marks a success for conservation, it has been contentious among pastoralists. Coincidentally, livestock guarding dogs (LGDs; Canis familiaris) have been widely adopted by producers of domestic sheep (Ovis aries) in the United States to mitigate livestock depredation by wild carnivores. We surveyed pastoralists to measure how experience with and attitudes towards LGDs related to attitudes towards livestock predators, and found positive responses regarding LGDs and negative responses regarding wolves and grizzly bears. The more respondents agreed that LGDs reduce the need for lethal management (p \u3c 0.01) and prevent the spread of disease (p \u3c 0.05), the more positive their opinion of wolves in the wild. Regarding wolves and livestock, respondents who disagreed with the statements that “LGDs do more harm than good” (p \u3c 0.05) or “reduce the need for lethal management” (p \u3c 0.001), were more likely to express more negative opinions of wolves. While results pertaining to a reduced need for lethal management may suggest LGDs have some ability to increase tolerance for wolves, the causal order of these effects is difficult to discern. A more positive attitude for wolves to begin with may predict more optimistic attitudes about the capacity of LGDs to reduce human–wildlife conflict. We found almost no support for the opinion that LGDs do more harm than good, even though attitudes towards wolves were generally negative. Respondents with up to 10 years’ experience using LGDs had more negative attitudes towards grizzly bears (p \u3c 0.01) and respondents with more than 10 years’ experience using LGDs had the most negative attitudes towards grizzly bears (p \u3c 0.001). Thus, while experience was the greatest predictor of attitudes towards grizzly bears, attitudes towards wolves were most correlated with the belief that LGDs offset the need for lethal management of carnivores. These results suggest that LGD use in the United States does not seem to have resulted in more positive attitudes about livestock predators amongst pastoralists

Post-Release Activity and Habitat Selection of Rehabilitated Black Bears

Despite the long history of wildlife rehabilitation and the abundance of empirical knowledge of the behavior and resource selection of wildlife species, rarely does research bridge these disciplines. Such investigations could be of value to wildlife managers and rehabilitators by revealing the suitability of the habitat at selected release sites, the wild activities, behavior, and fitness of the captive-reared individuals, and ultimately the efficacy of the rehabilitation process. Rehabilitated carnivores warrant specific attention, given that they are wide-ranging and may behave in ways that threaten human safety or interests. We investigated the behavior of orphan, rehabilitated black bear cubs (Ursus americanus) during their first year after release by utilizing GPS collars, resource selection functions, and generalized linear mixed models. To understand if rehabilitated individuals exhibited species-typical behaviors, we included metrics commonly reported in other empirical studies of this species, such as immediate post-release movements, denning chronology, release-site fidelity, and resource use. Rehabilitated bear cubs denned shortly after release exhibited late-summer dispersals, showed preferential selection for certain habitat types based on season, and displayed no inclination toward utilization of anthropogenic resources. The survival and behavior of the orphaned bears in this study suggest that welfare-based captive care and rehabilitation can be a safe and effective practice without habitation to humans or deleterious effects on fitness

Estimates of Energy and Prey Requirements of Wolverines

Wolverine (Gulo gulo) populations have decreased throughout much of their North American range and there is interest in establishing recovery programs in the Sierra Nevada of California and the Rocky Mountains of Colorado. Determining the sufficiency of prey resources is an important consideration for initiating wolverine recovery, yet there are limited data on resource availability and needs. Our goal is to estimate prey requirements based on wolverine caloric needs and the caloric content of prey likely to be available. We achieve this goal by modifying existing models to account for wolverine biology. Models show a male wolverine requires 5096 kJ/day (2925-7462 kJ) and a female wolverine requires 3645 kJ/day (2158-5439 kJ). This translates to an annual energy budget for males of 1.9 million kJ/yr that could be met by consuming the equivalent of approximately 8 mule deer/yr (Odocoileus hemionus) and 1.4 million kJ/yr for females that could be met by consuming the equivalent of less than 6 mule deer/yr. In light of published records of prey availability, these results suggest populations of wolverines could be sustained where recovery programs are being considered in Colorado and California. We suggest incorporating energetic needs of focal species, such as those calculated here for wolverines, into the assessment of resource availability before implementing recovery programs. Further, these estimates can be applied to management and conservation of wolverines throughtout their range

Wildlife responses to livestock guard dogs and domestic sheep on open range

Domestic sheep (Ovis aries) are an attractant to carnivores; however, sheep are often accompanied by humans and livestock guardian dogs (LGDs; Canis familiaris), which defend sheep from depredation. Sheep also compete directly with wildlife for grazing resources. Although practiced for millennia in much of the world outside North America, the effect that transhumance has on wildlife is poorly understood. To test the effect of sheep bands (sheep, humans, and LGDs) on wildlife, we modeled the detection probability of wild mammals relative to the presence of sheep bands in the Northwestern United States. Sheep band presence was associated with a reduction of about half in the likelihood of detecting large carnivores (Ursus americanus, Ursus arctos, Canis lupus, and Puma concolor, p \u3c 0.05) and deer (Odocoileus spp., p \u3c 0.01), both while the band was present and after it left the area. Contrastingly, coyotes (Canis latrans) were more than three times as likely to be detected when sheep bands were present (p \u3c 0.001), and twice as likely after sheep bands left (p \u3c 0.01). Coyotes were the only species we modeled that was more likely to be detected when a sheep band was present. It is unclear how long these effects persist after a sheep band has moved through an area, but our results suggest that transhumance temporarily displaces many large mammals, which results in mesopredator release of coyotes. This study suggests there is a tradeoff between the conservation benefits provided by LGDs and humans protecting sheep and the costs of displacement to some wild mammals

Interactions with Humans Shape Coyote Responses to Hazing

Medium and large carnivores coexist with people in urban areas globally, occasionally resulting in negative interactions that prompt questions about how to reduce human-wildlife conflict. Hazing, i.e., scaring wildlife, is frequently promoted as an important non-lethal means for urbanites to reduce conflict but there is limited scientific evidence for its efficacy. We used a population of captive coyotes (Canis latrans) to simulate urban human-coyote interactions and subsequent effects of hazing on coyote behavior. Past experiences with humans significantly affected the number of times a coyote approached a human to necessitate hazing. Coyotes that had been hand fed by adults had to be more frequently hazed than coyotes with other or no past experiences with adults. Past experience with children had no impact on the number of hazing events. The number of times a coyote approached an adult or child was reduced across days based on the accumulative number of times hazed, suggesting coyotes learn to avoid behaviors warranting hazing and that this could be used as a non-lethal management tool. However, prior experience and whether the interaction is with an adult or child can alter the outcomes of hazing and must be considered in determining the efficacy of hazing programs

Scavenging vs hunting affects behavioral traits of an opportunistic carnivore

Background. Human-induced changes to ecosystems transform the availability of resources to predators, including altering prey populations and increasing access to anthropogenic foods. Opportunistic predators are likely to respond to altered food resources by changing the proportion of food they hunt versus scavenge. These shifts in foraging behavior will affect species interactions through multiple pathways, including by changing other aspects of predator behavior such as boldness, innovation, and social structure. Methods. To understand how foraging behavior impacts predator behavior, we conducted a controlled experiment to simulate hunting by introducing a prey model to captive coyotes (Canis latrans) and compared their behavior to coyotes that continued to scavenge over one year. We used focal observations to construct behavioral budgets, and conducted novel object, puzzle box, and conspecific tests to evaluate boldness, innovation, and response to conspecifics. Results. We documented increased time spent resting by hunting coyotes paired with decreased time spent active. Hunting coyotes increased boldness and persistence but there were no changes in innovation. Our results illustrate how foraging behavior can impact other aspects of behavior, with potential ecological consequences to predator ecology, predator-prey dynamics, and human-wildlife conflict; however, the captive nature of our study limits specific conclusions related to wild predators. We conclude that human-induced behavioral changes could have cascading ecological implications that are not fully understood

Effects of early‑life experience on innovation and problem‑solving in captive coyotes

Early-life experience often shapes behaviors like innovation and exploration. These behaviors are important to animals encountering novel food resources in diverse habitats, such as mesocarnivores in urban areas. To understand if early-life experiences impact later-life behavior, we examined how coyotes (Canis latrans) responded to a multi-access puzzle box at two life stages: pup (~ 7 weeks) and dispersal (~ 10 months). We first exposed pups, still living with their parents and littermates, to a baited puzzle box. At dispersal age, we again tested both these pups and an age-matched control group that was not exposed to the puzzle box as pups, both as individuals and with their pair-mate. We quantified problem-solving capability, latency to approach, and time spent in proximity to the puzzle box. Most pup litters solved two of the three access points, but no dispersal-age coyotes solved any access point. The amount of time dispersal-age coyotes spent near the box during pair-testing increased with (1) more time spent near the box during single-testing, (2) more time their pair-mate spent near the box during pair-testing, and (3) if their pair-mate came from a litter that previously solved the box. These results suggest that early-life experience and social interactions influence exploratory behavior at dispersal age, but coyotes exhibit increased avoidance behavior at this life stage, which corresponds with the life stage that overall survivorship decreases. Our study provides insight into how early-life experiences shape adult behavior in mesocarnivores

Production of Hybrids between Western Gray Wolves and Western Coyotes

Using artificial insemination we attempted to produce hybrids between captive, male, western, gray wolves (Canis lupus) and female, western coyotes (Canis latrans) to determine whether their gametes would be compatible and the coyotes could produce and nurture offspring. The results contribute new information to an ongoing controversy over whether the eastern wolf (Canis lycaon) is a valid unique species that could be subject to the U. S. Endangered Species Act. Attempts with transcervically deposited wolf semen into nine coyotes over two breeding seasons yielded three coyote pregnancies. One coyote ate her pups, another produced a resorbed fetus and a dead fetus by C-section, and the third produced seven hybrids, six of which survived. These results show that, although it might be unlikely for male western wolves to successfully produce offspring with female western coyotes under natural conditions, western-gray-wolf sperm are compatible with western-coyote ova and that at least one coyote could produce and nurture hybrid offspring. This finding in turn demonstrates that gamete incompatibility would not have prevented western, gray wolves from inseminating western coyotes and thus producing hybrids with coyote mtDNA, a claim that counters the view that the eastern wolf is a separate species. However, some of the difficulties experienced by the other inseminated coyotes tend to temper that finding and suggest that more experimentation is needed, including determining the behavioral and physical compatibility of western gray wolves copulating with western coyotes. Thus although our study adds new information to the controversy, it does not settle it. Further study is needed to determine whether the putative Canis lycaon is indeed a unique species

Global shifts in mammalian population trends reveal key predictors of virus spillover risk.

Emerging infectious diseases in humans are frequently caused by pathogens originating from animal hosts, and zoonotic disease outbreaks present a major challenge to global health. To investigate drivers of virus spillover, we evaluated the number of viruses mammalian species have shared with humans. We discovered that the number of zoonotic viruses detected in mammalian species scales positively with global species abundance, suggesting that virus transmission risk has been highest from animal species that have increased in abundance and even expanded their range by adapting to human-dominated landscapes. Domesticated species, primates and bats were identified as having more zoonotic viruses than other species. Among threatened wildlife species, those with population reductions owing to exploitation and loss of habitat shared more viruses with humans. Exploitation of wildlife through hunting and trade facilitates close contact between wildlife and humans, and our findings provide further evidence that exploitation, as well as anthropogenic activities that have caused losses in wildlife habitat quality, have increased opportunities for animal-human interactions and facilitated zoonotic disease transmission. Our study provides new evidence for assessing spillover risk from mammalian species and highlights convergent processes whereby the causes of wildlife population declines have facilitated the transmission of animal viruses to humans