Physical Sciences and Mathematics Commons^™

Changes In Fecal Glucocorticoid Metabolites In Captive Coyotes (Canis Latrans): Influence Of Gender, Time, And Reproductive Status, Eric M. Gese, Patricia A. Terletzky, Cole A. Bleke, Erika T. Stevenson, Susannah S. French

USDA Wildlife Services: Staff Publications

Simple summary

Biologists have long considered producing offspring a demanding time in the life of any animal, with reproducing and raising offspring being physiologically stressful. We examined whether breeding and producing pups was more stressful than other life-history stages among captive coyotes (Canis latrans) using fecal sampling and subsequent assays for glucocorticoid metabolites. Using 12 pairs of coyotes (five pairs produced pups, seven pairs did not), we examined fecal glucocorticoid metabolites (fGCM) covering 11 biological time periods for one year. We found high individual variability among both females and males with no apparent statistical effect of reproduction on …

Scavenging Vs Hunting Affects Behavioral Traits Of An Opportunistic Carnivore, Mitchell A. Parsons, Andrew Garcia, Julie K. Young

USDA Wildlife Services: Staff Publications

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 …

Social Learning Of Avoidance Behaviors: Trap Aversion In Captive Coyotes, Julie Young, Jeffrey T. Schultz, Buck Jolley, Nekol Basili, John P. Draper

USDA Wildlife Services: Staff Publications

Social learning can help animals gain knowledge rapidly and may enhance survival. In species that are subjected to capture in foothold traps and then lethally removed, such as the coyote (Canis latrans), learning to avoid traps is critical to survival. Here, we tested social learning of trap avoidance behavior in three experimental scenarios with captive coyotes. In the first experiment, coyotes observed an unfamiliar coyote get captured in a foothold trap (i.e., demonstrator) or did not observe a demonstrator and were therefore naïve to traps. The coyotes that observed a demonstrator showed similar latencies to approach the trap …

Mesopredator Frugivory Has No Effect On Seed Viability And Emergence Under Experimental Conditions, John P. Draper, Trisha B. Atwood, Noelle G. Beckman, Karin M. Kettenring, Julie K. Young

USDA Wildlife Services: Staff Publications

Members of the order Carnivora are a unique and important seed disperser who consume and deposit undamaged seeds while providing regular long-distance seed dispersal opportunities. Some members of Carnivora, such as coyotes (Canis latrans), are undergoing range expansions which may help the plant species they consume colonize new locations or replace dispersal services provided by recently extirpated species. In this study, we evaluated aspects of the seed dispersal effectiveness of coyotes and gut passage time to determine the potential dispersal distances for three commonly consumed and commonly occurring plant species (Amelanchier alnifolia, Celtis ehrenbergiana, and Juniperus osteosperma). We also investigated …

Surgical Sterilization Impacts On Behavior Of Coyote Pairs, Tyler Leary, Jeffrey T. Schultz, Julie K. Young

USDA Wildlife Services: Staff Publications

Coyotes (Canis latrans) involved in depredation of livestock, an act frequently resulting in human-wildlife conflict, often do so out of necessity for provisioning pups. Surgical sterilization methods such as vasectomy that preserve gonadal hormones have been successful in reducing depredation by free-ranging coyotes while allowing individuals to maintain territoriality and mate fidelity. However, use of these methods remain costly and ineffective for wide-scale use. Given the alternative proposal of using chemical sterilization techniques, we investigated whether the use of hormone-altering sterilization methods impacted behavior of captive coyote pairs (i.e., male-female pair bonds). Our objective was to evaluate behavior …

Space Use In Free-Ranging Canids: Are Gonadal Hormones Required For Territory Maintenance?, Eric M. Gese, Patricia A. Terletzky

USDA Wildlife Services: Staff Publications

Fertility control among carnivores has been used to reduce depredations on livestock and wild neonates, population control, modify behavior, inhibit genetic introgression, and reduce human–wildlife conflicts. Although there is considerable knowledge on techniques to sterilize carnivores, there is little information concerning how the absence of gonadal hormones influences behavior, space use, and survival of wild canids. We examined territorial fidelity, home-range size and overlap, and survival of 179 surgically sterilized free-ranging canids (124 coyotes (Canis latrans Say, 1823), 55 coyote – red wolf (Canis rufus Audubon and Bachman, 1851) hybrids) with gonadal hormones present (tubal-ligated females (n = 70), vasectomized …

Improving Evaluation Of Nonlethal Tools For Carnivore Management And Conservation: Evaluating Fladry To Protect An Endangered Species From A Generalist Mesocarnivore, R. M. Windell, L. L. Bailey, J. K. Young, T. M. Livieri, D. A. Eads, S. W. Breck

USDA Wildlife Services: Staff Publications

Carnivore conservation and management are global research priorities focused on reversing population declines of imperiled species and identifying more effective and humane management of generalist carnivores with thriving populations. Nonlethal methods to mitigate conflict are increasingly used to advance conservation objectives; however, there is limited knowledge about the effectiveness of many nonlethal methods. We tested a nonlethal tool (fladry), that serves as a barrier to deter wolves Canis lupus and coyotes Canis latrans, for its efficacy at preventing coyotes from using prairie dog Cynomys ludovicianus colonies, the primary prey for critically endangered black-footed ferrets Mustela nigripes. We used …

Instability Of Glucocorticoid Metabolites In Coyote Scats: Implications For Field Sampling, Erika T. Stevenson, Eric M. Gese, Lorin A. Neuman-Lee, Susannah S. French

USDA Wildlife Services: Staff Publications

Studying physiologic stress responses can assist in understanding the welfare of animals. One method of measuring the physiologic stress response is evaluating concentrations of glucocorticoid metabolites in feces. Previously, using an adrenocorticotropic hormone challenge, we found fecal glucocorticoid metabolite levels were a reliable indicator of physiologic stress response in coyotes (Canis latrans). We determine whether glucocorticoid metabolite concentrations remain stable when collecting feces over a 2-week period, a timeframe commonly used in scat surveys for wild canids. We collected feces from 6 captive coyotes maintained at the U.S. Department of Agriculture, Wildlife Services, National Wildlife Research Center, Predator …

Mind The Gap: Experimental Tests To Improve Efficacy Of Fladry For Nonlethal Management Of Coyotes, Julie K. Young, John Draper, Stewart Breck

USDA Wildlife Services: Staff Publications

Coyotes (Canis latrans) are the top predator of livestock in the contiguous United States. Developing more effective nonlethal tools to prevent coyote depredation will facilitate coexistence between livestock producers and coyotes. Fladry is a nonlethal deterrent designed to defend livestock by creating a visual barrier to wolves (C. lupus). Fladry may also be effective with coyotes, but large gap spacing between flags may reduce its efficacy. To address this issue, we performed 2 experiments on captive coyotes using fladry modified to reduce gap spacing at the U.S. Department of Agriculture, Predator Research Facility in Millville, Utah, USA, during 2015–2016 and …

Effects Of Coyote Population Reduction On Swift Fox Demographics In Southeastern Colorado, Seija M. Karki, Eric M. Gese, Mead L. Klavetter

USDA Wildlife Services: Staff Publications

The distribution and abundance of swift foxes (Vulpes velox) has declined from historic levels. Causes for the decline include habitat loss and fragmentation, incidental poisoning, changing land use practices, trapping, and predation by other carnivores. Coyotes (Canis latrans) overlap the geographical distribution of swift foxes, compete for similar resources, and are a significant source of mortality amongst many swift fox populations. Current swift fox conservation and management plans to bolster declining or recovering fox populations may include coyote population reduction to decrease predation. However, the role of coyote predation in swift fox population dynamics is not …

Does Interference Competition With Wolves Limit The Distribution And Abundance Of Coyotes?, Kim Murray Berger, Eric M. Gese

USDA Wildlife Services: Staff Publications

1. Interference competition with wolves Canis lupus is hypothesized to limit the distribution and abundance of coyotes Canis latrans, and the extirpation of wolves is often invoked to explain the expansion in coyote range throughout much of North America.

2. We used spatial, seasonal and temporal heterogeneity in wolf distribution and abundance to test the hypothesis that interference competition with wolves limits the distribution and abundance of coyotes. From August 2001 to August 2004, we gathered data on cause-specific mortality and survival rates of coyotes captured at wolf-free and wolf-abundant sites in Grand Teton National Park (GTNP), Wyoming, USA, …

Does Interference Competition With Wolves Limit The Distribution And Abundance Of Coyotes?, Kim Murray Berger, Eric M. Gese

USDA Wildlife Services: Staff Publications

1. Interference competition with wolves Canis lupus is hypothesized to limit the distribution and abundance of coyotes Canis latrans, and the extirpation of wolves is often invoked to explain the expansion in coyote range throughout much of North America.

2. We used spatial, seasonal and temporal heterogeneity in wolf distribution and abundance to test the hypothesis that interference competition with wolves limits the distribution and abundance of coyotes. From August 2001 to August 2004, we gathered data on cause-specific mortality and survival rates of coyotes captured at wolf-free and wolf-abundant sites in Grand Teton National Park (GTNP), Wyoming, USA, …

Cameras, Coyotes, And The Assumption Of Equal Detectability, Eveline Se Quin Larrucea, Peter F. Brussard, Michael M. Jaegar, Reginald H. Barrett

USDA Wildlife Services: Staff Publications

Remote cameras are an increasingly important tool in management and wildlife studies. However, we often do not know if they provide an unbiased sample of populations. Using a marked, radio-collared population of coyotes (Canis latrans) of known social status, we evaluated the influence of temporal (daily and seasonal) and spatial (distance between units, habitat, and proximity to human structures) factors on vulnerability to photo-captures. During 8 unbaited camera sessions of 6 weeks each, we obtained 158 coyote photographs at a photo-capture success rate of 1.6%. We were able to identify not only marked individuals, but also a number …

Coyote Investigative Behavior Following Removal Of Novel Stimuli, Daniel J. Heffernan, William F. Andelt, John A. Shivik

USDA Wildlife Services: Staff Publications

Because coyotes (Canis latrans) show an aversion to novel objects, we examined the effects of the presence and removal of repellent and attractive stimuli on coyote behavior. We found a greater proportion of captive coyotes investigated 10-cm-tall cones (0.95) compared to 90-cm-tall cones (0.68) and control sites (0.81), and spent longer periods (P , 0.001 in all instances) investigating small cones (x̅ = 465 sec), compared to large cones (x̅ = 212 sec) and control sites (x̅ = 45 sec). However, investigation times at sites following removal of large cones were 1.6 and 2.3 times …

A Broad Perspective On Current And Future Research On Urban Coyotes, John A. Shivik, Kathleen Fagerstone

USDA Wildlife Services: Staff Publications

A change in wildlife management appears to be occurring. Previous efforts needed to be focused on producing more game species or endangered animals; now, however, tools and training must resolve issues of overabundance and conflict with predators, especially species such as coyotes (Canis latrans) in urban areas. Urban conflicts with coyotes may be growing because of urban development of land and human intrusion, but alteration of habitats that attract coyotes is also a likely factor. Research that will describe basic coyote biology in urban areas will be needed, but managers will also need applied research and development of …

Information Content Of Coyote Barks Howls, Brian R. Mitchell, Maja M. Makagon, Michael M. Jaeger, Reginald H. Barrett

USDA Wildlife Services: Staff Publications

The information content of coyote (Canis latrans) vocalizations is poorly understood, but has important implications for understanding coyote behavior. Coyotes probably use information present in barks or howls to recognize individuals, but the presence of individually-specific information has not bean demonstrated. We found that coyote barks and howls contained individually specific characteristics: discriminant analysis correctly classified barks of five coyotes 69% of the time and howls of six coyotes 83% of the time. We also investigated the stability of vocalization characteristics at multiple distances from the source. Recordings were played back and re-recorded at 10 m, 600m, and …

Initial Comparison: Jaws, Cables, And Cage-Traps To Capture Coyotes, John A. Shivik, Daniel J. Martin, Michael J. Pipas, John Turnan, Thomas J. Deliberto

USDA Wildlife Services: Staff Publications

The need for alternative predator capture techniques is increasing because of concerns about the efficiency, selectivity, and injury of currently available capture methods. There also is a need for comparative data evaluating new or seldom used methods. In an initial evaluation, we first surveyed wildlife managers for information on cage-trapping; using these data, we conducted a field study of 4 coyote (Canis latrans) capture systems for animal damage management. We tested the SoftCatch®, Collarum®, Wildlife Services–Turman, and Tomahawk®, systems for capturing coyotes in Arizona and south Texas during 2001 and 2002. We determined capture efficiency and selectivity and …

Coyote Movements And Social Structure Along A Cryptic Population Genetic Subdivision, Benjamin N. Sacks, Brian R. Mitchell, Christen L. Williams, Holly B. Ernest

USDA Wildlife Services: Staff Publications

A recent region-wide study determined that the central California coyote ( Canis latrans ) population was genetically subdivided according to habitat bioregions, supporting the hypothesis that coyotes exhibit a dispersal bias toward their natal habitat type. Here, we further investigated this hypothesis using radio-collared coyotes captured on a 150-km 2 study site on the border of (i.e. overlapping) two bioregions (Great Valley and Cascade Mountains). As predicted, most coyotes were assigned (based on a priori genetic criteria) to genetic clusters corresponding to one of these two bioregions. All of those assigned to the Great Valley genetic cluster were caught in …

Serologic Survey For Canine Infectious Diseases Among Sympatric Swift Foxes (Vulpes Velox) And Coyotes (Canis Latrans) In Southeastern Colorado, Eric M. Gese, Seija M. Karki, Mead L. Klavetter, Edward R. Schauster, Ann M. Kitchen

USDA Wildlife Services: Staff Publications

Swift foxes (\'IL~VPGCY~ OX)a nd CoVi I otes (C~rrisl r~tr(~r~a.rse) sympatric canids distributed througllout rnany regions of tlie Great Plains of North America. ~h~ prevalence of canid diseases arnong these two species where they occur syiripatrically is presently unknown. Frorn January 1997 to January 2001, we collected blood salnples from 89 switt toxes and 122 coyotes oil the US Arlny Pifion Canyon Maneuver Site, 1,as Anilrlas County, SE lorado (USA). Seroprcvalence of ailtibodies against canine parvovirr~s (C13\i) was 71 % for adult (>9 nlo old) ailcl 38% for jrlveilile (59 Ino old) swift fbxes. Adult (21 yr old) and …

Coyote Depredation Management: Current Methods And Research Needs, Brian R. Mitchell, Michael M. Jaeger, Reginald H. Barrett

USDA Wildlife Services: Staff Publications

This paper examines the severity of livestock depredation by coyotes (Canis latrans), reviews evidence implicating breeding (or “alpha”) coyotes in the majority of incidents, evaluates currently used depredation control techniques, and suggests directions for future research. Nonlethal control ranges from varied animal husbandry practices to coyote behavioral modification or sterilization. These methods show significant promise but have not been proven effective in controlled experiments. Therefore, many livestock producers rely on lethal control, and most employ nonselective strategies aimed at local population reduction. Sometimes this approach is effective; other times it is not. This strategy can fail because the …

Weight And Age Of Coyotes Captured In Virginia, John M. Houben, J. Russell Mason

USDA Wildlife Services: Staff Publications

We recorded the weight and age of 70 coyotes collected during depredation control efforts in western Virginia. Mean masses for adult male and female coyotes were 16.2 and 13.4 kg, respectively. Juvenile male and female coyotes weighed 14.0 and 13.0 kg, respectively. Regardless of sex, mean mass was greatest between November and January and comparable to that reported for coyotes throughout the eastern United States. Cementum aging indicated that 71% of the coyotes captured were greater than 1 year of age. Numerical trends suggest that age and sex may influence vulnerability to capture.

Coyote Depredation Management: Current Methods And Research Needs, Brian R. Mitchell, Michael M. Jaegar, Reginald H. Barrett

USDA Wildlife Services: Staff Publications

This paper examines the severity of livestock depredation by coyotes (Canis latrans), reviews evidence implicating breeding (or “alpha”) coyotes in the majority of incidents, evaluates currently used depredation control techniques, and suggests directions for future research. Nonlethal control ranges from varied animal husbandry practices to coyote behavioral modification or sterilization. These methods show significant promise but have not been proven effective in controlled experiments. Therefore, many livestock producers rely on lethal control, and most employ nonselective strategies aimed at local population reduction. Sometimes this approach is effective; other times it is not. This strategy can fail because the …

Seasonal Activity Areas Of Coyotes In The Bear River Mountains Of Utah And Idaho, Glen F. Gantz, Frederick F. Knowlton

USDA Wildlife Services: Staff Publications

We studied the seasonal movement patterns and dispersal of coyotes (Canis latrans) in the Bear River Mountains of northern Utah and southern Idaho to determine whether coyotes in this montane region exhibit an altitudinal migration on a seasonal basis. We used 3 locational parameters to assess whether a seasonal altitudinal migration was evident, including overlap in seasonal activity areas, distance between harmonic mean centers of activity, and seasonal differences in mean elevations of locations. Winter and summer activity areas of every mature coyote overlapped, with mean distances between harmonic centers of seasonal activity of 1.5 km (range = 0.4–3.3 km). …

Temporal Genetic Variation In A Coyote (Canis Latrans) Population Experiencing High Turnover, Christen Lenney William, Karen Blejwas, John J. Johnston, Michael M. Jaeger

USDA Wildlife Services: Staff Publications

Coyotes (Canis latrans) are mobile, adaptable canids found in a wide range of habitats across North America, with range extensions into previously unoccupied areas in the western and eastern United States. Although long-distance dispersal capabilities in both sexes (Harrison 1992) and relatively large proportions of transient coyotes that do not exhibit fidelity to a single territory (typically 13–34% of a population— Andelt 1985; Windberg and Knowlton 1988) suggest that coyotes exist as a panmictic population, other aspects of coyote behavior may increase the likelihood of local population structure.

Coyote-Activated Frightening Devices For Reducing Sheep Predation On Open Range, Kurt C. Vercauteren, Michael J. Lavelle, Steve Moyles

USDA Wildlife Services: Staff Publications

Domestic sheep ranching is an important agricultural industry in the United States and coyote (Canis latrans) depredation on lambs and ewes continues to challenge ranchers and agencies responsible for protecting sheep. Lethal methods used in controlling coyote depredation include aerial gunning, toxicants, trapping, and calling and shooting. Nonlethal methods include frightening devices, fences, livestock protection animals, and stringent husbandry practices. Ranchers and agencies responsible for controlling coyote depredation need frightening devices that are more effective than those currently available. We describe a field evaluation of 2 animal-activated frightening devices: an acoustic device and an acoustic device with a …

Coyote-Activated Frightening Devices For Reducing Sheep Predation On Open Range, Kurt C. Vercauteren, Michael J. Lavelle, Steve Moyles

USDA Wildlife Services: Staff Publications

Domestic sheep ranching is an important agricultural industry in the United States and coyote (Canis latrans) depredation on lambs and ewes continues to challenge ranchers and agencies responsible for protecting sheep. Lethal methods used in controlling coyote depredation include aerial gunning, toxicants, trapping, and calling and shooting. Nonlethal methods include frightening devices, fences, livestock protection animals, and stringent husbandry practices. Ranchers and agencies responsible for controlling coyote depredation need frightening devices that are more effective than those currently available. We describe a field evaluation of 2 animal-activated frightening devices: an acoustic device and an acoustic device with a …

Reproduction In Captive Wild-Caught Coyotes (Canis Latrans), Jeffrey S. Green, Frederick F. Knowlton, William C. Pitt

USDA Wildlife Services: Staff Publications

We assessed reproductive patterns of coyotes (Canis latrans) from a 12-year data set involving 24 pairs of captive animals acquired from Latah County, Idaho. None of the females had placental scars (fetal implantation sites) at 1 year of age, but over 80% had placental scars by 2 years of age. The fraction with placental scars remained at 80–90% through age 9 years and then declined to ,40% by age 12 years. Similarly, mean number of placental scars per female rose rapidly through 2–3 years of age, remained stable until age 8 years, and then progressively declined to a …

Safety Of Brucella Abortus Strain Rb51 Vaccine In Non-Target Ungulates And Coyotes, Terry J. Kreeger, Thomas J. Deliberto, Steven C. Olsen, William H. Edwards, Walter E. Cook

USDA Wildlife Services: Staff Publications

Brucellosis is endemic in free-ranging elk (Cervus elaphus) and bison (Bison bison) in the Greater Yellowstone Area (GYA; USA). It is possible that an oral brucellosis vaccine could be developed and disseminated in the GYA to reduce disease transmission. Should this occur, non-target species other than elk and bison may come in contact with the vaccine resulting in morbidity or mortality. To assess biosafety, bighorn sheep (Ovis canadensis; n=10), pronghorn (Antilocapra americana; n=9), mule deer (Odocoileus hemionus; n=11), moose (Alces alces shirasi; n=10), and …

Surgical Sterilization As A Method Of Reducing Coyote Predation On Domestic Sheep, Cassity Bromley, Eric M. Gese

USDA Wildlife Services: Staff Publications

Predation by coyotes (Canis latrans) on domestic sheep is a problem for many livestock producers throughout the United States Intermountain West. We examined whether surgical sterilization of coyote packs would modify their predatory behavior and reduce predation rates on domestic sheep as compared to coyote packs with pups. From June 1997 to December 1997, we gathered baseline information on coyote pack size and movements. In winter 1998, we surgically sterilized and radio-collared members of 5 coyote packs. We also captured and radio-collared members of 6 packs that remained intact (i.e., reproductive). During summer 1998, only 1 sterile pack …

Pulp Cavity-Tooth Width Ratios From Known-Age And Wild-Caught Coyotes Determined By Radiography, Frederick F. Knowlton, Susan L. Whittemore

USDA Wildlife Services: Staff Publications

Although the relative sizes of pulp cavities in teeth are used frequently to identify various age classes of carnivores, validation of the technique has received little attention. We measured the pulp cavities and tooth widths based on radiographs of canine and premolar teeth from a large sample of known-age, pen-reared coyotes (Canis latrans) and from samples of wild-caught coyotes of unknown age. The ratio of pulp cavity to tooth width decreased rapidly through the first year of life. Although canine tooth ratios of juvenile, yearling, and adult coyotes differed, variations within yearling and adult groups precluded accurate assignment …