SPIRIT LAKE, Utah (AP) – Utah wildlife officials are killing every fish in a group of high-elevation lakes and streams to make way for a restocking of native Colorado River cutthroat trout.
They dumped the fish-killing rotenone into waterways of the Uinta mountains, about 100 miles east of Salt Lake City.
“I don’t want to kill fish,” Trina Headrick, northeastern region aquatics manager for the Utah Division of Wildlife Resources, told KSL-TV. “But it is the tool that we have to restore this native (species) to this drainage. So, you know, we’re not bad people. We’re just trying to do a good thing for a species that really has seen heavy impact over the last 50 to 100 years.”
Officials treated eight pristine mountain lakes and connecting streams in the Sheep Creek drainage.
After a waiting period, they will restock Spirit Lake and other waterways with Colorado River cutthroats, which inhabit less than 15 percent of their original range in Utah, Colorado and Wyoming.
The fish kill was designed to rid the waterways of nonnative species including brown trout, brook trout and rainbow trout that are blamed for crowding out their cutthroat cousins.
“Pure forms of the Colorado River cutthroat trout have not been found in this drainage for many, many years,” Headrick said.
On Wednesday, a team of 60 people were working the Middle Fork of the Sheep Creek with boats, backpack sprayers and five-gallon buckets.
“These high lakes are just absolutely awesome,” said Jeff Tanaguchi, president of the High Desert Anglers chapter of Trout Unlimited. “We’d like to see the cutthroat thrive.”
The project had been under study for years. It covered about eight miles of streams along with Spirit, Jessen, Tamarack, Gail, Judy, Columbine, Lost and Hidden lakes. It is being funded by the U.S. Fish & Wildlife Service, the Utah Blue Ribbon Fisheries Advisory Council and other organizations.
Officials say cutthroat trout first appeared in the Rocky Mountain region around a million years ago. They’ll have to wait until 2014 before being reintroduced in the High Uintas.
The drainage will be free of rotenone within the next three weeks. At that point the Division of Wildlife Resources will temporarily stock Spirit Lake with tiger trout, a sterile hybrid that won’t cause problems for the Colorado River cutthroats.
Fisheries biologists say they were careful to use the lowest possible doses of rotenone to spare aquatic bugs in the lakes and streams. The concentration used was below what the U.S. Environmental Protection Agency deems unsafe for human exposure, and it shouldn’t be a problem for any animals that eat dead fish carcasses, Headrick said.
Rotenone is a poison derived from the seeds of certain plants, such as jicama. It has been used by indigenous people to catch fish for thousands of years. It also keeps mites off chickens. All uses for rotenone other than killing fish are being phased out in the U.S. and Canada.
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