Why biologists put a jolt of electricity in Provo River fish

A group of biologists and volunteers collect fish by electrofishing at the Provo River Thursday. The fish were measured and weighed before returning to the river.

A group of biologists and volunteers collect fish by electrofishing at the Provo River Thursday. The fish were measured and weighed before returning to the river. (Stuart Johnson, KSL-TV)

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Estimated read time: 3-4 minutes

PROVO — A group of Utah wildlife biologists and volunteers descended into the Provo River on Thursday armed with peculiar-looking fishing nets.

A thick yellow line, hooked to a generator floating on a small pontoon boat nearby, was attached to the poles that volunteers held. The line ran down to the net, allowing those wading through the water to essentially zap a fish, scoop it up and quickly dump it off for sampling.

This was no fish fry and the ones caught were OK. Experts say the electric jolt only temporarily immobilizes the fish so they rise to the top of the water, allowing for them to be collected, measured and weighed. After the information is collected, the fish are dropped back into the river and swim away.

"With electricity, it's a nonlethal way for us to sample the fish population," said Mike Slater, sportfish project leader for the Utah Division of Wildlife Resources. "It stuns these fish for a few seconds. It allows all our volunteers and guides to hurry and net them and then put them into some water that they'll be able to revive in."

The work conducted Thursday, referred to as "electrofishing surveys," may seem odd but it's actually important for the Utah Division of Wildlife Resources and groups invested in helping fish habitats.

The division, Trout Unlimited and several private donors purchased about 20 cubic feet per second, for a section of the Lower Provo River by the mouth of Provo Canyon. The deal cost close to $1 million over the next decade, according to Slater.

This stake of the water rights allows water to continue to flow downstream instead of going toward irrigation or hydropower generation; water continuing downstream is crucial for fish and other wildlife habitats. Parts of the river suffer from periods of low flow and almost dry up in the heat of summer in some cases, Slater explained.

"(The purchased water) allows the fish, it allows the frogs, other aquatic life to thrive, to continue," he said.

It also helps those who like to catch fish. State wildlife officials estimate that the Lower Provo River attracts about 7,000 anglers per mile annually. By buying water rights, they believe they're able to keep fish swimming and help anglers catch fish year-round.

All of this leads back to Thursday.

Experts needed to know exactly how many fish are in the Lower Provo River, especially since they put a large investment into securing water rights.

So they shocked the fish and gathered information about them. The process helps experts collect "baseline information" to help them better understand the fish population and the overall health of the population, Slater said. He's pleased with what was discovered Thursday.

"(I'm) really excited with what we just saw," he said, standing several yards from the riverbank. "Lots of brown trout, lots of whitefish, lots of sculpin — a myriad of different species of fish that are hanging out in here."

They are all fish species that experts expect to thrive over the next decade.

Said Slater: "I perceive they'll be able to continue to do so because of this water that we've been able to secure."

Contributing: Stuart Johnson, KSL-TV



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