Why Did the Government Kill Every Fish in a River?

A couple months ago, we published an article about a proposed poisoning of Soda Butte Creek outside of Cooke City, Montana. The proposal, supported and enacted by various government agencies and non-profits including Trout Unlimited, was aimed at removing invasive brook trout from a stream that used to be dominated by the Yellowstone cutthroat trout. The invasive brookies were outcompeting the Yellowstone cutties, slowly diminishing their numbers.

For the most part, the locals in Cooke City were against this move, claiming that the brook trout threat was way overrated by those who wanted to poison the creek.

“I’ve been fishing here for 22 years and I’ve only ever caught one brook trout” said one local.

“All we have to do is tell all the fishermen to kill brook trout and the problem will be solved in no time” said another. Both these statements were met with murmurs of agreement around the bar.

But this past September, Montana Fish, Wildlife & Parks, the Wyoming Game & Fish Department, National Park Service, and the U.S. Forest Service went ahead with the creek poisoning.

For 20 years prior, the government agencies had been electro-fishing throughout Soda Butte Creek, stunning all the fish in a pool and removing the invasive brook trout. After 20 years, fish biologists were not satisfied with the amount of brook trout still in the creek. They decided to get together and do something different, however more drastic it might seem. This time, they would remove as many of the Yellowstone cutthroat as possible and then dump rotenone, an EPA approved piscicide in the water. This would completely wipe out all the leftover invasive brookies. After the piscicide had ran its course, the Yellowstone cutties would be returned to their now exclusive habitat. And that’s pretty much exactly what happened.

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Photo by Fish, Wildlife, Parks

fish, wildlife, parks

Photo by Fish, Wildlife, Parks

There have been creek poisonings in the past that have successfully restored native trout populations, but this one was slightly different. In the poisoning of Soda Butte Creek, the fish biologists removed as many Yellowstone cutthroat as possible before adding the piscicide to the water. The fish were placed in a temporary holding pool in a nearby tributary. After the poison had ran its course and the river was detoxified with potassium permanganate, the original fish were returned to Soda Butte Creek.

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Soda Butte Creek

Story originally published in The Montana Standard

Cover picture also by Fish Eye Guy Photography