Domestic animals can die for a variety of reasons—due to disease, weather, injury, and predators. When a livestock owner believes wolves caused the loss or injury of their livestock, ODFW uses an evidence-based investigation process to determine if wolves were involved. The goal is not to determine the livestock animal’s cause of death, as in some cases that could require a veterinary pathologist (e.g., illness, injury, age, poisonous plants).
When doing an investigation, ODFW closely examines the physical evidence (on the animal or the scene) to determine if the domestic animal was actually killed or injured by a predator—and not just scavenged by one after dying from another cause. If the death or injury is determined to be predator-caused, further examination is needed to determine if wolves (rather than coyotes, cougars, bears, or domestic dogs) were responsible.
Most confirmed wolf attacks show pre-mortem bite scrapes and severe tissue trauma in specific locations (rear hindquarters above the hock, elbows, and flanks) on the animal. In some cases, livestock losses cannot be confirmed to be caused by wolves because there is not enough evidence. In others, an investigation finds the domestic animal died by an entirely different cause. More detail on the classifications used is below.
In some counties in Oregon, USDA Wildlife Services assists ODFW when wolves are suspected and is the lead agency to investigate when other predators such as coyotes, bear, or cougar are suspected. In some counties, sheriff’s deputies also attend investigations. ODFW needs to make the determination for lethal removal of chronically depredating wolves to be considered or if the livestock producer wants financial compensation from the Oregon Department of Agriculture.
Recent Livestock Investigations (pdf)
Past Investigation Reports