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Rat poison from illegal California marijuana grows threatens rare forest animals

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While the stereotypical image of marijuana farmers depicts them as Earth-friendly environmentalists, a proliferation of less scrupulous growers using rat poison to ward off pests on illegal farms may be responsible for killing scores of rare weasel-like mammals called fishers, which are already on the verge of protection under the Endangered Species Act.

As reported by the Summit County Voice, a new study by researchers at UC Davis, the Integral Ecology Research Center and other land agencies found that almost 80 percent of the fisher carcasses studied had been exposed to anticoagulant rodenticides. Brodifacoum, a second-generation rodenticide, was found in 96 percent of the dead animals. The researchers are looking at illegal public marijuana farms as the source for introducing the toxic chemicals to the remote, wooded areas where fishers dwell. The animals are often attracted by bacon and peanut butter “flavorizers” added for that very purpose.

“The findings in this paper could signal a looming conservation threat for other species as well as fishers,” said Sean Matthews, Wildlife Conservation Society scientist and co-author of the findings in a press release. “As we discuss in the study, depletion of rodent prey populations upon which fishers and other animals feed, along with the anticoagulant poisoning threat might affect the Sierra Nevada red fox, wolverine, California spotted owls and other rare carnivores that inhabit the region.”

“To humans, the threat is [the poisons used in marijuana gardens] can go into other species ... such as game resources for humans,” said Mourad Gabriel, lead author of the study to the Huffington Post, with drug enforcement agencies also concerned about potential dangers from ingesting such treated marijuana. “It does pose a risk.”