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PGE's fish sorting facility is 'the first of its kind'

by: ISABEL GAUTSCHI - Biologist Garth Wyatt pauses to identify this fish as hatchery or wild.PGE recently completed work on a first-of-its kind fish sorting facility.

For the first time, biologists are able to separate native from hatchery fish with the press of a button.

Prior to the construction of the North Fork Adult Sorting Facility, PGE fish biologists had to climb into holding pools and physically separate the fish with nets.

PGE fish biologist Garth Wyatt explains that there are two main schools of practice with fish separation: physical separation (with nets) or anesthetization.

PGE fish biologist Tim Shibahara pointed out that, “Both are fairly stressful for the fish.”

The biologists explained that physically netting fish removes part of their “slime coating” which acts as their first layer of defense against disease and infection.

Fish that have been netted often develop fungal infections that attack their immune systems. This can be fatal.

But PGE has constructed a $4.3 million facility that provides an alternative method of fish separation.

“This has never been done before. This is the first of its kind to be able to sort hatchery from wild fish without physically handling them or anesthetizing,” Wyatt said of the North Fork Adult Sorting Facility.

The biologists noted that PGE’s extraordinary efforts to separate hatchery from native fish have been somewhat mandated.

“The reason we separate them is to operate in accordance with Oregon Department of Fish and Wildlife’s fish policy,” Wyatt said.

He explained that when native and hatchery fish breed, the species loses some “genetic fitness.” Meaning that they no longer reproduce at the same rate and are not as strong as native fish.

“A hatchery is essentially a Medicare system for fish,” Wyatt said.

Wyatt went on to explain that hatchery fish have a 99 percent survival rate from egg to smolt while native fish have a mere 5 percent survival rate from egg to smolt.

However, that 5 percent is a hearty bunch of fish.

The native fish that survive into adulthood have strong disease resistance, ability to get food and avoid predators.

These qualities have been selected into their genetic code, which is believed to get significantly watered down when hatchery fish get mixed into the gene pool. The result is a weaker species.

Shibahara points out that this is a “controversial issue.”

“My scientific position is that there’s loss of genetic fitness on an individual level,” Wyatt said, but explained that the affect of the interbreeding of native and hatchery fish on an entire fish population has yet to be determined.

“Oregon Department of Fish and Wildlife thinks it’s better to separate,” Shibahara said.

The result?

The biologists will continue to act as chaperones, keeping hatchery coho and chinook salmon from breeding with endangered “wild” fish.

The issue got even more complicated for PGE with its relicensing agreement with the Federal Energy Regulatory Commission (FERC).

In 2010, PGE received a relicensing agreement from FERC to continue operating its Clackamas River hydro projects for another 45 years.

But the company had to agree to make a series of environmental improvements to its facilities, especially in regard to fish passage.

However, the relicensing agreement prohibited sorting fish manually or through anesthetization.

Even though, as the biologists pointed out, separation by any other means had never been done before.

So they built the North Fork Adult Sorting Facility.

Wyatt came up with the concept and gave it to a design team.

Construction began in July 2012 and the facility was operational by May 6, 2013.

Here’s how it works

Adult fish enter “the longest working fish ladder in the world” at Faraday Diversion Dam.

They swim up roughly 1.5 miles along the ladder when they encounter the North Fork Adult Sorting facility.

The fish encounter a weir, or barrier, and can no longer swim upstream as their instinct dictates, so they jump into a 16-feet-deep holding pool.

The water is cooler in the holding pool than on the fish ladder, which gives the fish an incentive to hop in.

Inside the facility, biologists open a gate that shoots fish into an observation tank.

A laser system, similar to the technology that powers automatic sliding doors, is able to send fish into separate observation tanks, in case more than one fish slips through the gate at a time.

What gets those fish through the gate?

Biologists are able to raise the floor in the holding tank, lowering the water level and crowding the fish.

Fish act on instinct to get out of the situation and slip through the gate into an observation tank.

The facility is designed to use fish behavior to its advantage.

In the observation tank, the biologist looks for the presence of an adipose fin on the fish’s back.

Hatcheries remove this fin.

If the fish has the fin, it’s deemed to be “wild” and is immediately released to continue on its way along the ladder to the upper Clackamas River Basin.

Those fish without an adipose fin are sent to a hatchery fish holding tank. The hatchery fish are either “recycled downstream for anglers to have another shot” or taken to the Clackamas Hatchery.

“The whole design of this facility was to be able to operate with one person and hold hatchery fish for 24 hours. Wild fish are released immediately,” Wyatt said of the design.

It’s fairly involved for one person. They must open the gate, quickly determine whether the fish is native or hatchery, adjust the observation tank and water if the fish came through the gate the wrong way, and get it out of the observation tank to its proper destination.

When Wyatt demonstrates the process, he uses his whole body to operate the system.

Even though the biologists later laugh that it’s “like playing video games” they also admit that it takes “muscle memory.”

Everyone that operates the facility now is “biologist level,” but Wyatt said eventually they hope to train technicians to be able to operate the system.

The biologists note that they are still making improvements to aid fish comfort (they’ve added something called a “salmon pillow” to the observation tanks) and to ease the operation of the facility.

Shibahara said there has been “a lot of trial and error,” especially when dealing with unexpected fish behavior in the observation tanks.

“We’re changing things on a weekly basis,” Wyatt said. “The goal is to get (the fish) through (the observation tanks) as quickly as possible.”

Wyatt estimates the facility is handling about 50 fish a day but expects to handle more depending on the season.

PGE’s previous sorting facility once handled 1,100 fish in one record-breaking day.

So the new facility has been designed to handle that many in a “worst case scenario.”




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