Bears Prefer Trees in the Spring

As they emerge from their winter den, bears need an energy source and food is relatively scarce. Concurrently, trees are breaking dormancy and starting to generate carbohydrates. Consequently, bears commonly girdle Douglas-fir trees during the spring to feed on the available carbohydrates. Bears strip bark from a tree with their claws, then feed on the sapwood by scraping it from the heartwood with their teeth. Scattered remnants of bark strewn at the base of a tree and vertical tooth marks are characteristic indicators of bear activity. Most frequently bears forage on the lower bole of trees, girdling the bottom three to five feet. However, some bears may climb and feed on the upper boles while sitting on lateral branches. Occasionally, a bear will strip an entire tree

WILDLIFE IMPACTS ON FOREST RESOURCES

The negative impacts of wildlife on forest resources can be extensive. This paper provides some insight into the economic and environmental consequences of wildlife damage to forest resources and a brief overview of the damage inflicted by select wildlife species. Probably the most thorough measure of wildlife damage to forests in the Pacific Northwest was initiated in 1963 and 1964 by the Committee on Animal Damage Survey of the Western Forestry and Conservation Association. This study estimated that 30% of the tree seedlings planted would be damaged if no preventive practices were implemented; stocking rates on unprotected sites were 75% of those on protected sites; and trees protected from animal damage were 33% taller than unprotected trees after 5 years. Updating the economic numbers to reflect present day values, this damage results in an annual financial loss in Oregon of US$333 million. The total predicted reduction in value of the forest asset in Oregon, if no animal damage management was practiced, was estimated to be US$8.3 billion. Results from a recent survey conducted by the Oregon Forest Industry Council also provides insight into economic losses due to damage by select species: mountain beaver (US$6.8 million) and bear (US$11.5 million)

Non-Target Impacts of Strychnine Baiting to Reduce Pocket Gopher Populations on Forest Lands in the united States

Reforestation efforts are often severely hindered on sites that contain high populations of pocket gophers (Thmmysspp). Strychnine baiting is a technique used to suppress pocket gopher populations until seedlings are established. Strychnine bait is applied below ground in pocket gopher burrows, however, primary and secondary hazards remain a concern. A study to assess primary hazards indicated that some individual rodents died post strychnine baiting but there was not a long-term negative impact on non-target rodent populations. Possible secondary hazards reflect the potential for predators OT scavengers to encounter poisoned pocket gophers. Concerns that pocket gophers may surface before they succumb to the bait have been reduced through data acquired in pen trials. Most pocket gophers in trials with natural ground cover died in or near nest and all died below-ground. Carcasses of non-target species may pose some risk. These carcasses, however, are few and are thought to be consumed by insects within a few days. Trials are being conducted to evaluate the fate of these carcasses and to assess whether insects that feed on strychnine-containing carcasses pose a tertiary hazard

Assessing the efficacy of registered underground baiting products for mountain beaver (Aplodontia rufa) control

The mountain beaver (Aplodontia rufa) is a fossorialrodent species endemic to the Pacific Northwest and portions of California. This herbivore inflicts millions of dollars of damage annually to forest seedling plantations. Currently, extensive trapping prior to planting is the most reliable method for reducing damage. With increasing restrictions placed on trapping, forest resource managers need alternative tools to minimize forest damage. This study assessed the potential of four toxicants registered for underground use to controlmountain beaver; zinc phosphide, diphacinone, chlorophacinone, and strychnine. Zinc phosphide and strychnine are acute toxicants, whereas diphacinone and chlorophacinone are anticoagulants. Anticoagulants prevent the recycling of vitamin K in the body, which inhibits the production of clotting factors. Efficacy varied among treatments. Zinc phosphide and strychnine were avoided by mountain beaver. Pre-baiting marginally increased acceptance of strychnine, but did not alter mountain beaver acceptance of zinc phosphide. Diphacinone and chlorophacinone were both readily consumed, but only chlorophacinone was 100% effective after a 14-day baiting regime. Subsequently, we tested the effects of diet on the efficacy of diphacinone by varying the availability of food containing vitamin K, the anticoagulant antidote. Restricting access to potential sources of vitamin K appeared to increase efficacy. We conclude that anticoagulants hold some promise as additional tools for managers to reduce mountain beaver populations with chlorophacinone showing the most promise. However, limitations to anticoagulant baits include the necessity of long-term baiting (greater than 10 days), a possible decrease in toxicity if baits contact moisture, and potential primary hazards

Assessing the efficacy of registered underground baiting products for mountain beaver (Aplodontia rufa) control

The mountain beaver (Aplodontia rufa) is a fossorialrodent species endemic to the Pacific Northwest and portions of California. This herbivore inflicts millions of dollars of damage annually to forest seedling plantations. Currently, extensive trapping prior to planting is the most reliable method for reducing damage. With increasing restrictions placed on trapping, forest resource managers need alternative tools to minimize forest damage. This study assessed the potential of four toxicants registered for underground use to controlmountain beaver; zinc phosphide, diphacinone, chlorophacinone, and strychnine. Zinc phosphide and strychnine are acute toxicants, whereas diphacinone and chlorophacinone are anticoagulants. Anticoagulants prevent the recycling of vitamin K in the body, which inhibits the production of clotting factors. Efficacy varied among treatments. Zinc phosphide and strychnine were avoided by mountain beaver. Pre-baiting marginally increased acceptance of strychnine, but did not alter mountain beaver acceptance of zinc phosphide. Diphacinone and chlorophacinone were both readily consumed, but only chlorophacinone was 100% effective after a 14-day baiting regime. Subsequently, we tested the effects of diet on the efficacy of diphacinone by varying the availability of food containing vitamin K, the anticoagulant antidote. Restricting access to potential sources of vitamin K appeared to increase efficacy. We conclude that anticoagulants hold some promise as additional tools for managers to reduce mountain beaver populations with chlorophacinone showing the most promise. However, limitations to anticoagulant baits include the necessity of long-term baiting (greater than 10 days), a possible decrease in toxicity if baits contact moisture, and potential primary hazards

BLACK BEAR DAMAGE MANAGEMENT IN WASHINGTON STATE

Black bears (Ursus americanus) foraging on trees can be extremely detrimental to the health and economic value of a timber stand. A supplemental feeding program to reduce bear damage is coordinated by the Washington Forest Protection Association\u27s Animal Damage Control Program (ADCP). A brief overview of the ADCP is provided along with a description of bear damage and the supplemental feeding program. Success of the feeding program is demonstrated by an increasing participation and its general acceptance by the public. Timber producers placed over 400 thousand pounds of pellets in 700 feeding stations this past year

BLACK BEAR DAMAGE MANAGEMENT IN WASHINGTON STATE

Black bears (Ursus americanus) foraging on trees can be extremely detrimental to the health and economic value of a timber stand. A supplemental feeding program to reduce bear damage is coordinated by the Washington Forest Protection Association\u27s Animal Damage Control Program (ADCP). A brief overview of the ADCP is provided along with a description of bear damage and the supplemental feeding program. Success of the feeding program is demonstrated by an increasing participation and its general acceptance by the public. Timber producers placed over 400 thousand pounds of pellets in 700 feeding stations this past year

The National Feral Swine Program, National Strategy – The First Five Years

In 2014, through Congressional direction, the Animal Plant Health Inspection Service (APHIS) National Feral Swine Damage Management Program was created. While feral swine damage management was certainly not new to APHIS Wildlife Services, this mandate enabled a programmatic and unified approach in combating the destructive forces of feral swine throughout the United States and its territories. Recognizing the variance in environmental conditions and regulatory processes throughout the states, APHIS’ strategy is to provide resources and expertise at a national level, while allowing flexibility to manage operational activities from a local or state perspective. Having completed the first five years of this pursuit, APHIS has compiled a report which serves to describe the program and its components, ongoing collaborative research, the operational approach, and the outreach and communication campaigns. This presentation provided an overview of this report, introducing accomplishments achieved, setbacks encountered, and future considerations. The report will be electronically available on the USDA/APHIS/Wildlife Services web page at: https://www.aphis.usda.gov/aphis/ourfocus/wildlifedamag

Training Deer to Avoid Sites Through Negative Reinforcement

Deer frequently visit areas where they may cause damage. Incidents along roadways and runways inflict numerous injuries to animals and humans, and cause considerable economic losses. Concerns are increasing that deer interactions with domestic animals may contribute to spread of disease. Deer foraging in residential areas, agricultural fields, or plant propagation sites can impede growth and possibly survival of desirable plants. We conducted a series of trials to determine whether mild electric shock would induce place avoidance in deer. Shock was delivered through a device attached to a collar. A noise cue was emitted as an animal approached a defined area if the animal failed to retreat a shock followed. Deer learned to avoid areas associated with shock. We concluded that place avoidance induced through negative reinforcement may be a feasible means to protect valuable resources from resident animals. However, the technological limitations of tested devices, costs to implement, and required training for individual deer reduced the practicality of this approach for highly mobile animals and as a means to protect resources with low economic significance

Assessing the Efficacy of Chlorophacinone for Mountain Beaver (\u3ci\u3eAplodontia rufa\u3c/i\u3e) Control

The mountain beaver is a fossorial rodent species endemic to the Pacific Northwest and portions of California. This herbivore is managed as a pest species because of the impact it has on newly planted Douglas-fir seedlings. Currently, managers are limited to trapping for population control; however, in Washington trapping has been further curtailed by anti-trapping legislation. Presently there are no registered underground toxicants for mountain beaver control. We have documented the efficacy of chlorophacinone, presented in daily doses, as a possible alternative for mountain beaver control. Daily baiting would be unreasonable and costly alternative for timber managers, so we conducted a series of tests to determine if a single or double baiting was efficacious. In addition, we tested the caching behavior of the mountain beaver when offered bags of oats. This behavior may help reduce impacts to non-target species as well reduce environmental exposure and degradation. Mountain beaver readily cached bags of chlorophacinone within their artificial burrows, and efficacy of a one-lime and two-time dose was 100%. We determined that even with the highest chlorophacinone residuals (0.354 ppm) that the risk quotient for mink and red-tailed hawk was exactly at the level of concern that EPA recognizes for endangered and threatened species