Along California's North Coast, so much marijuana is grown that the region has become known as the "emerald triangle." As states hash out laws regarding humans' use of pot, though, some point out that it's not just a human concern: Fish and wildlife proponents say salmon are feeling the negative effects of the marijuana industry.
It takes a huge amount of water to run pot farms, and many marijuana growers draw that water from rivers. And NPR reports that pesticides and fertilizers are also being found in those rivers where Chinook and other salmon swim.
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According to Scott Bauer, a fisheries biologist with the California Department of Fish and Wildlife, 24 tributaries of the Eel River went dry last summer. It's unlikely that Chinook and Coho salmon will return in large numbers in coming years, he told NPR. Some fear they won't return to certain rivers at all.
"I have nothing against people growing dope," Dave Bitts, a Humboldt County commercial fisherman and the president of the Pacific Coast Federation of Fishermen's Associations, told NPR.
"But if you do, we want you to grow your crop in a way that doesn't screw up fish habitat. There is no salmon-bearing watershed at this point that we can afford to sacrifice."
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It's not the first inkling that animals and cannabis don't mix: This summer, a study found that rat poison used on pot farms may be killing fishers, a sensitive species of medium-sized mammals, in the southern Sierra Nevada.
"Exposure of wildlife to pesticides has been widely documented, but this is a fundamentally different scenario," said wildlife biologist Dr. Kathryn Purcell.
"In marijuana cultivation sites, regulations regarding proper use of pesticides are completely ignored and multiple compounds are used to target any and all threats to the crop, including compounds illegal in the U.S.," she said.
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