We Get Support From:
Become a Supporter 
 We Get Support From:
Become a Supporter 

Study: Rat Poison On Marijuana Farms Killing Fishers

Mourad Gabriel / Integral Ecology Research Center / UC Davis

This is the amount of rat poison found at just one illegal marijuana grow site in Northern California. Research by UC Davis and Integral Ecology Research Center shows rat poison on such sites is increasingly killing fishers.

Mourad Gabriel / Integral Ecology Research Center / UC Davis

A UC Davis study shows more fishers are dying from rodenticides used on illegal marijuana farms. The mid-sized weasels are threatened under the California Endangered Species Act.

The study published in the journal PLOS ONE, shows increasing numbers of fishers are being exposed to and dying from greater varieties of rodenticides found on illegal pot farms. The study builds on 2012 research that recorded four fisher deaths and found a 79 percent exposure rate.

Since then nine more fishers have died, and exposure rates have increased to 85 percent. Mourad Gabriel with the Integral Ecology Research Center was the lead author.

"If the fisher is being impacted, and it’s an omnivorous carnivore that consumes a wide breadth of prey species, then other species of concern are most likely also at risk,” says Gabriel.

Gabriel says the number of illegal pot farms on public lands has also increased, which could account for the greater number of fisher deaths.


Amy Quinton

Former Environment Reporter

Amy came to Sacramento from New Hampshire Public Radio (NHPR) where she was Environment Reporter. Amy has also reported for NPR member stations WFAE in Charlotte, WAMU in Washington D.C. and American Public Media's "Marketplace."  Read Full Bio 

Sign up for ReCap

and never miss the top stories

Delivered to your inbox every Wednesday.

Check out a sample ReCap newsletter.