National Wildlife Research Center

FY 2019

Improving Methods To Manage Healthy Forests, Wetlands and Rangelands

Contact Information:

Dr. Jimmy Taylor Supervisory Research Wildlife Biologist c/o Oregon State University 321 Richardson Hall Corvallis, OR 97331

Phone: (541) 737-1353 E-mail: jimmy.d.taylor@usda.govNWRC Web site: www.aphis.usda.gov/wildlifedamage/nwrc/OSU Web site:http://fes.forestry.oregonstate.edu/faculty/taylor-jimmy

Groups Affected:

Commercial timber producersGardeners/LandscapersHomeownersNatural resource managersNoncommercial forest landownersOil and gas industriesOrchard managersRanchersState departments of transportationUtility cooperatives

Major Cooperators:

Bighorn Basin Conservation Districts, WyomingBritish Columbia Ministry of Forests and RangeDepartment of DefenseMississippi State UniversityNational Council for Air and Stream ImprovementOregon Department of Fisheries and Wildlife Oregon Department of ForestryOregon Forest Industries CouncilOregon State UniversityPortland State UniversityThe Jack Berryman InstituteU.S. Department of DefenseUSDA Forest ServiceUSGS Forest and Rangeland Ecology Science CenterWashington Department of Fisheries and WildlifeWashington Department of Natural ResourcesWashington Forest Protection Association Wyoming Game and Fish Department

National Wildlife Research Center Scientists Develop Methods to Reduce Wildlife Damage in a Variety of Habitats

Wildlife Services' (WS) National Wildlife Research Center (NWRC) is the only Federal research facility devoted exclusively to resolving conflicts between people and wildlife through the development of effective, selective, and socially responsible methods, tools, and techniques. NWRC's expertise in Corvallis, Oregon, focuses primarily on wildlife damage to forest, wetland and rangeland resources.

Wildlife impacts on regenerating forests following wildfire or harvesting can be extensive. Cutting and gnawing on seedlings by deer, elk, mice, mountain beavers, pocket gophers, rabbits, and voles during the first five years of tree growth greatly hinder reforestation efforts. Other mammals, such as bears and porcupines damage mature trees. North American beavers and nutria alter riparian vegetation, which limits streamside restoration efforts, erodes roads and railways, and can endanger human health and safety. Common raven populations have increased significantly across North America, and the damage they cause to agriculture and ground-nesting birds, such as snowy plover and greater sage-grouse, is perceived to have increased as well. NWRC scientists are developing nonlethal tools and methods to help manage wildlife damage to these important habitats and resources.

Applying Science & Expertise to Wildlife Challenges

Economic Impacts of Black Bear Damage to Douglas-fir Trees. Black bear damage to timber resources is an ongoing concern, yet few tools exist to assess current damage and potential future impacts. Black bears peel conifers in early spring to forage on energy-rich inner layers. NWRC researchers and university partners surveyed black bear damage to Douglas-fir tree stands in western Washington and Oregon, and used distance-dependent, individual tree growth and yield models to evaluate economic impacts using two damage scenarios. The first damage scenario (Salvage) accounted for mortality and volume losses of both fully and partially girdled trees while valuing removal of partially damage trees. The second damage scenario (Total Loss) assumed complete loss of all black bear-peeled trees regardless of the amount peeled. Damage resulted in economic losses ranging from 4 to 16 percent (Salvage) and 17 to 46 percent (Total Loss) of net present value. Damage losses in the Total Loss scenario were on average four times greater than those in the Salvage scenario. A second study using the same methodology at a landscape scale found that the economic impact under both damage scenarios was less than 0.35 percent of net present value, suggesting that black bear damage is not evenly distributed. The study also showed that aerial surveys overestimated bear damage by about 5-fold due to misclassification with root disease and failed to detect partially peeled trees that contributed to economic loss. This approach may help improve forest management plans that assess damage by black bears and other wildlife species.

Habitat Use by American Beaver. NWRC and university researchers used a combination of modeling techniques along with GPS locations, presence-absence data, and vegetation characteristics to determine if variables explaining beaver habitat selection are consistent between landscape and fine spatial scales. Contrary to their predictions, results showed that woody wetland edge density, shrub edge density, and open water edge density were important in beaver habitat selection at both landscape and fine spatial scales. Researchers also noted that food resources including woody plants may limit beaver fitness and subsequently determine beaver habitat selection during winter and spring. In a separate beaver study, NWRC and university researchers demonstrated that Dirichlet-multinomial distribution models and Bayesian spatial resource selection functions provide alternative approaches to the presence–absence methods for determining habitat selection by animals.

Wildlife Services Protecting People ♦ Protecting Agriculture ♦ Protecting Wildlife

The U.S. Department of Agriculture is an equal opportunity employment provider and employer

Predation Effects on Greater Sage-grouse Nest Survival. Greater sage-grouse (Centrocercus urophasianus) populations in North America have declined and now occupy only 56 percent of their historical range. Low nest survival is one factor limiting sage-grouse population growth. NWRC, Oregon State University, and Utah State University researchers attached transmitters on female sage-grouse to identify and monitor the fate of 204 sage-grouse nests in the Bighorn Basin, Wyoming. The researchers also used trail cameras to identify predators at nest sites. Results showed coyotes to be the greatest contributor to nest failure, followed by common ravens, abandonment, and female mortality. The direct effect of nest predation by coyotes in this study was greater than other reported sage-grouse studies, yet the nest survival rates were consistent with others reported throughout the species' range. Coyote removal to protect livestock and big game did not appear to have indirect effects on nest survival, such as increased depredation by other species (i.e., badger, raven, red fox). Nest survival was lowest on a site where coyotes and ravens depredated nests at nearly the same rate, and where ravens were observed nesting on infrastructure close to nesting sage-grouse.

Selected Publications:

Francis, R.A., J.D. Taylor, E. Dibble, B. Strictland, V.M. Petro, C. Easterwood, and G. Wang. 2017. Restricted cross-scale habitat selection by American beavers. Current Zoology 63(6):703-710. doi: 10.1093/cz.zox059

Taylor, J.D., R.D. Holt, E.K. Orning, and J.K. Young. 2017. Greater sage-grouse nest survival in Northwestern Wyoming. Journal of Wildlife Management 81:1219-1227. doi: 10.1002/jwmg.21296

Kline, K.N., J.D. Taylor, and A.T. Morzillo. 2018. Estimating stand-level economic impacts of black bear damage to intensively managed forests. Canadian Journal of Forest Research 48:758-765. doi:10.1139/cjfr-2017-0314

Petro, V.M., J.D. Taylor, D.M. Sanchez, and K.M. Burnett. 2018. Methods to predict beaver dam occurrence in coastal Oregon. Northwest Science 92(4): 278-289. doi: 10.3955/046.092.0405

Taylor, J.D., K.N. Kline, and A.T. Morzillo. 2019. Estimating economic impact of black bear damage to western conifers at a landscape scale. Forest Ecology and Management 432:599-606. doi: 10.1016/j.foreco.2018.10.005

Wang, G., L.F. McClintic, and J.D. Taylor. 2019. Habitat selection by American beaver at multiple spatial scales. Animal Biotelemetry 7:10. doi: 10.1186/s40317-019-0172-8

Major Research Accomplishments:

• WS economic models estimated black bear damage toDouglas-fir trees ranged from 4 to 46 percent of the timber'snet present value at the forest stand scale, but beardamage at the landscape scale was less than 0.35 percent.Researchers note black bear damage is not evenlydistributed and remotely-sensed damage to trees wasoverestimated due to misclassification with root diseases.

• WS research on beaver habitat selection indicated foodresources, including woody plants, may limit beaver fitnessand subsequently determine beaver habitat selection duringwinter and spring.

• WS research indicated that Dirichlet-multinomial distributionmodels and Bayesian spatial resource selection functionsprovide alternative approaches to the presence–absencemethods for determining habitat selection by animals.

• WS research showed greater sage-grouse nest survivalranged from 20 to 56 percent in Bighorn Basin, WY. Nestdepredation by coyotes was the greatest contributor to nestfailure in this area, although coyote management forlivestock and big game did not appear to have noticeableeffects on nest survival rates.