Gregory E. Phillips

Reproductive Success of Elk Following Disturbance by Humans during Calving Season

Restricting human activity in elk (Cervus elaphus) calving areas during calving season can be controversial because of increasing human uses of elk habitat, and little evidence exists to evaluate impacts of these activities on elk populations. We evaluated effects of human-induced disturbance on reproductive success of radiocollared adult female elk using a control-treatment study in central Colorado. Data were collected during 1 pretreatment year and 2 treatment years. Treatment elk were repeatedly approached and displaced by study personnel throughout a 3-4-week period of peak calving during both treatment years, while control elk did not receive treatment. We observed elk on alpine summer ranges in July and August on both areas to estimate the proportion of marked cows maintaining a calf. Calf/cow proportions for the control area remained stable, but those for the treatment area declined each year. Average number of disturbances/elk/year effectively modeled variation in calf/cow proportions, supporting treatment as the cause of declining calf/cow proportions. Average decrease in calf/cow proportion in the treatment group was 0.225. Modeling indicated that estimated annual population growth on both study areas was 7% without treatment application, given that existing human activities cause some unknown level of calving-season disturbance. With an average of 10 disturbances/cow above ambient levels, our model projected no growth. Our results support maintaining disturbance-free areas for elk during parturitional periods. JOURNAL OF WILDLIFE MANAGEMENT 64(2):521-530

Livestock Protection Dogs for Deterring Deer From Cattle and Feed

Abstract Disease transmission between wildlife and livestock is a worldwide issue. Society needs better methods to prevent interspecies transmission to reduce disease risks. Producers have successfully used livestock protection dogs (LPDs) for thousands of years to reduce predation. We theorized that LPDs raised and bonded with cattle could be used to also reduce risk of bovine tuberculosis (Myobacterium bovis; TB) transmission between white-tailed deer (Odocoileus virginianus) and cattle by minimizing contact between the 2 species and use of cattle feed by deer. We evaluated 4 LPDs over 5 months, utilizing 2 data collection methods (direct observation and motion-activated video) on deer farms that supported higher densities than wild populations. Dogs were highly effective in preventing deer from using concentrated cattle feed (hay bales), likely the greatest risk factor of TB transmission on farms. Dogs also prevented deer from approaching cattle in core areas of pastures (near hay bales) and were very effective throughout pastures. Our research supports the theory that LPDs, specifically trained to remain with cattle, may be a practical tool to minimize potential for livestock to contract TB from infected deer in small-scale cattle operations. Where disease is present in deer, it may be possible to reduce the potential for disease transmission by employing LPDs.

Fence-Line Contact Between Wild and Farmed White-Tailed Deer in Michigan: Potential for Disease Transmission

Abstract Interactions between wild and farmed white-tailed deer (Odocoileus virginianus) along perimeter fences may play a role in the transmission of diseases like bovine tuberculosis and chronic wasting disease. However, no study has evaluated direct contact between wild and farmed deer through fences. We used animal-activated cameras to estimate rates of interaction between wild and farmed deer at 6 high-fenced commercial white-tailed deer farms in Michigan, USA, during October 2003 to January 2005. We recorded only 2 direct, naso-oral contacts between wild and farmed deer during >77,000 hours of camera monitoring. We documented little direct contact between wild and captive deer through fences and, therefore, believe there is limited potential for direct transmission of diseases. However, we suspect our results are conservative and do not rule out the risks of direct or indirect disease transmission into or out of deer farms. Our findings will be of use to federal and state agencies responsible for regulating deer farms as well as managers of such facilities.

Elk Use of Wallows and Potential Chronic Wasting Disease Transmission

Deposition of prions into the environment by infected animals may contribute to transmission and spread of chronic wasting disease (CWD) among free-ranging cervids, and identification of such environmental sources may provide an avenue for managing CWD. We evaluated the role that wallow use by elk (Cervus elaphus) may play in CWD transmission by monitoring wallows with animal-activated cameras throughout their period of use. We monitored 39 wallows from 5 August 2005 to 14 October 2005. Elk visited 20 sites; we recorded 22 events when only male elk wallowed and 374 additional events when male and female elk had naso-oral contact with wallow contents. Because wallows are foci of male elk activity, behaviors at wallows could potentially contribute to the maintenance and transmission of CWD. Our findings, however, suggest that because wallows are only used an average of one or two times a season they may not be important in CWD transmission. The data also suggest that mineral licks could be more important in CWD transmission because they were used more frequently and by three species that contract CWD.

Evaluation of Fences for Containing Feral Swine under Simulated Depopulation Conditions

ABSTRACT Populations of feral swine (Sus scrofa) are estimated to include >2 million animals in the state of Texas, USA, alone. Feral swine damage to property, crops, and livestock exceeds

Fence‐Line Contact Between Wild and Farmed Cervids in Colorado: Potential for Disease Transmission

50 million annually. These figures do not include the increased risks and costs associated with the potential for feral swine to spread disease to domestic livestock. Thus, effective bio-security measures will be needed to quickly isolate affected feral swine populations during disease outbreaks. We evaluated enclosures built of 0.86-m-tall traditional hog panels for containing feral swine during 35 trials, each involving 6 recently caught animals exposed to increasing levels of motivation. During trials, fences were 97% successful when enclosures were entered by humans for maintenance purposes; 83% effective when pursued by walking humans discharging paintball projectors; and in limited testing, 100% successful when pursued and removed by gunners in a helicopter. In addition to being effective in containing feral swine, enclosures constructed of hog panels required simple hand tools, took <5 min/m to erect, and were inexpensive (

A Fence Design for Excluding Elk Without Impeding Other Wildlife

5.73/m excluding labor) relative to other fencing options. As such, hog-panel fences are suitable for use by state and federal agencies for rapid deployment in disease response situations, but also exhibit utility for general control of other types of damage associated with feral swine.

A Frightening Device for Deterring Deer Use of Cattle Feeders

Abstract Direct and indirect contact between wild and farmed cervids along perimeter fences may play a role in transmission of diseases like chronic wasting disease (CWD), but no studies have quantified such interactions. At 9 high-fenced commercial elk (Cervus elaphus) farms in Colorado, USA, during October 2003 to January 2005, we used animal-activated video to estimate rates of fence-line use by wild cervids, rates of direct contact between farmed and wild cervids, and probability of direct contact when wild cervids were present. We recorded 8-fold-more wild elk per unit time than mule deer (Odocoileus hemionus) at fence lines. Depending on site, we recorded 0.66 to 46.90 wild elk per 1,000 hours of camera monitoring. We documented 77 interactions between wild and farmed elk involving naso-oral contact and no contact between wild mule deer and farmed elk. Rate of direct contact ranged from 0.00 to 1.92 direct contacts per 1,000 hours of camera monitoring among sites. Given recorded presence of wild elk, estimated probability of observing direct contact during a 2-minute video recording ranged from 0.00 to 0.11 among sites. Risk of direct contact was about 3.5 times greater for single woven-wire fence compared with offset electric fence attached to a single woven-wire fence. We observed no direct contact through double woven-wire fences. Because little is currently known about infection rates associated with infection mechanisms, we cannot infer a level of CWD infection risk from our results, but some form of double fencing should reduce potential for direct and indirect transmission of disease into or out of elk farms.

Mineral licks: motivational factors for visitation and accompanying disease risk at communal use sites of elk and deer

Abstract Concentrated herbivory by elk (Cervus elaphus) can degrade vegetative communities and alter ecosystem processes. Areas severely damaged by elk are commonly protected with woven wire fence, which can exclude other animals. Complete exclusion and prevention of large mammal herbivory might not always be necessary to restore vegetative communities. We designed and evaluated a simple fence that excluded elk, but maintained access for deer and other species. We enclosed a 1-ha stand of quaking aspen (Populus tremuloides Michaux) with our fence in an area with a high density of elk. We monitored effectiveness of the fence with trackplots, animal-activated cameras, and changes in aspen stem height and density. We documented only 1 elk within the exclosure in 2 years of monitoring. Mammals that used the exclosure included beaver (Castor canadensis), black bear (Ursus americanus), bobcat (Lynx rufus), coyote (Canis latrans), deer (Odocoileus spp.), mountain lion (Puma concolor), raccoon (Procyon lotor), red fox (Vulpes vulpes), and lagomorph (Leporidae). After 1 year of protection, mean aspen stem height increased 14.5 cm more inside the exclosure than outside, but stem density in the exclosure changed little compared to outside. Our fence design effectively excluded elk and has potential for protecting a variety of resources.

Procedures for Identifying Infectious Prions After Passage Through the Digestive System of an Avian Species

Abstract The presence of bovine tuberculosis (TB) in cattle can negatively impact a states economy and cattle industry. In Michigan, USA, wild white-tailed deer (Odocoileus virginianus) are a reservoir for reinfecting cattle herds. Although direct TB transmission between deer and cattle is rare, infected deer may contaminate cattle feed. To mitigate this risk, we designed and evaluated a deer-resistant cattle feeder (DRCF) device for deterring deer from feeders. The device delivered negative stimuli to condition deer to avoid cattle feeders. We tested the device by conducting a comparative change experiment at a high-density captive white-tailed deer operation in northeastern lower Michigan using pretreatment and treatment periods and random allocation of DRCF protection to 3 of 6 feeders during the treatment period. We used animal-activated cameras to collect data on deer use of feeders. Deer use was similar at protected and unprotected feeders during the pretreatment period but was lower at protected feeders during the treatment period. Deer-resistant cattle feeders were 100% effective during the first 2 treatment weeks, 94% during the first 5 weeks, but effectiveness then dropped to 61% during the final week. Excluding problems associated with low battery power and infrared sensors, DRCFs were 99% effective at deterring deer. Our results suggest that DRCFs can effectively limit deer use of cattle feed, potentially with minimal impact on feeding behavior of cattle, thus reducing potential transmission of bovine TB through contaminated feed. By employing DRCFs in bovine TB endemic areas, especially at times that deer are food stressed, agencies and producers can practically and economically reduce the potential for bovine TB to be transmitted from deer to cattle.