Pot growers poisoning wildlife?

Commercial rat poison used by illegal marijuana growers could be putting California’s wildlife at risk, particularly the fisher, a member of the weasel family. The fisher is currently a candidate for listing under the federal Endangered Species Act.

Researchers led by UC Davis veterinary scientists analyzed 58 fisher carcasses in Humboldt County near Redwood National Park and the southern Sierra Nevada in and near Yosemite National Park, finding 79 percent had been exposed to rodenticides, according to a UC Davis press release.

The study’s authors identified illegal pot farms in the study areas as the most likely source of the poison, as nontarget rodenticide poisoning usually occurs only in urban or agricultural settings—not the forested areas that fishers tend to inhabit.

The fishers may have been poisoned as a result of eating animals that had ingested the rodenticide, or may have consumed the bacon-, cheese- and peanut-butter-flavored poisons directly. Other species may be at risk as well, including the spotted owl and the Sierra Nevada red fox.