DNR biologists and a legion of volunteers from Indian bands, colleges, and all federal wetland districts and wildlife refuges place 4,000 to 5,000 scented disks in woods and uplands along standardized routes throughout the state. The disks, which contain a synthetic mixture of coyote urine and fermented powdered eggs, are placed on raked soil, which is checked for tracks the following day. The surveys provide information on foxes, raccoons, skunks, coyotes, dogs, and cats, as wells as bobcats, wolves, bears, and opossums. Spotters look for dammed ponds where new piles of willow and other food branches indicate active beaver colonies. Developed by DNR biologists and carried out with help from several Indian band conservation departments, the survey looks at pine marten and fisher tracks in the snow along 10-mile routes in northern Minnesota.
Biologists fly over known otter areas and count tracks in the snow.
They enter the locations into a Global Positioning System database. When ingested, the chemical shows up as a fluorescent mark when the bone or tooth is examined under ultraviolet light. Hunters who harvested bears were asked to provide a bone or tooth sample, from which wildlife researchers determined the percentage of bears that ate the bait. They divided this number into the number of baits eaten to estimate the total statewide population. Starting in the spring of 1999, biologists will capture fawns, attach radio collars, and then track the animals to learn what percent die during the summer.