Bulletin E-Edition:
more photosBrett Hodgson, left, of Oregon Department of Fish and Wildlife, and Cory Quesada, an employee with Portland General Electric, scoop captured fish out of Lake Billy Chinook on Wednesday afternoon. The fish were caught using a net that was close to 330 feet and pulled in anywhere from 500 to 1,000 fish at a time. They were then transported to a holding tank, where they were tagged with pink identifiers.
Anthony Dimaano / The Bulletin
Kokanee, long landlocked, may again be ocean-bound
Pink tags will help researchers monitor the experiment
By Lauren Dake / The Bulletin
Published: September 06. 2007 4:00AM PSTMADRAS — The kokanees’ glistening bodies slapped against each other in a desperate attempt to escape a confining net and return to the mouth of the Metolius River.
One by one, Megan Hill, a fisheries biologist with Portland General Electric, held them down.
With a flick of her wrist and the click of a staple gun-like tool, she attached a hot pink tag to each constrained fish behind its fin and tossed it in the cold, teal river.
“The joke is the tags are for the osprey,” she said, referencing the fish-eating birds flying above.
It’s possible that the fluorescent tags could help the winged predators spot the salmon.
But what Hill is really hoping for is that in a few weeks, the identifying labels will give her, and her colleagues, a sense of the kokanee population in Lake Billy Chinook.
The salmon tagging is the latest step in an elaborate $135 million plan to take the fish of Lake Billy Chinook to somewhere they haven’t been for close to a half-century: the ocean.
The Confederated Tribes of Warm Springs and the utility company own the Pelton Round Butte project.
The two groups, along with the Oregon Department of Fish and Wildlife, are hoping to succeed in a comprehensive fish passage program that will include a 273-foot tower to collect migrating fish. Once they are sucked up into the tower, the fish will be sorted and transported downstream past the dams, where they will hopefully make it to the ocean.
The goal Wednesday was to establish the necessary groundwork for a population estimate of the steadily declining numbers of kokanee. Once the tower is in place and the land-locked salmon have an option to be ocean-bound, it’s important that a substantial number of the salmon population either returns or remains in the reservoir.
If the researchers deem the population too low to transport to the Pacific, other steps will need to be taken.
Secondary options
“There are several options. One, we can try to increase the salmon by decreasing their mortality,” said Don Ratliff, a senior aquatic biologist with Portland General Electric.
Ratliff said the angler harvest could be reduced, or perhaps some of the predatory bull trout that enjoy a good kokanee snack could be donated to the Clackamas River. The last option would be to introduce non-native salmon stock into the reservoir. Since none of these options is ideal, Ratliff is keeping his fingers crossed that the kokanee population will be strong enough on its own.
The three hydroelectric dams built in the 1950s and 1960s have blocked salmon and steelhead from reaching the Pacific Ocean, where they would go to grow for a couple of years before returning to their native rivers to spawn.
The new intake tower, which will collect the migrating fish, is expected to be completed in 2009. It will be located around 700 feet upstream of Round Butte Dam. The estimated cost of the tower is $60 million.
“Nobody knows for sure exactly how well it will work,” Ratliff said. “It will be different from anywhere else in the world.”
Depressed population
Even without the project, there is already concern that the kokanee population is decreasing.
“By all estimates the kokanee population is depressed right now,” said Brett Hodgson, Pelton Round Butte mitigation coordinator with ODFW.
With the lower population of kokanees, the selective water withdrawal from the tower becomes a more sensitive issue.
The kokanee will either continue to be landlocked, and remain kokanee, or they will migrate to the ocean, becoming sockeye.
The sockeye is the anadromous, or ocean-bound, version of the landlocked kokanee species.
The third option is they will be lost to predators, such as the endangered bull trout that happen to be thriving in Lake Billy Chinook.
“How the pie is sliced and what will happen to the kokanee, no one knows,” Hodgson said.
The goal is to keep the kokanee population large enough to send a substantial amount to the Pacific, while keeping enough in the area for the bull trout to feed on and for the popular fishing spot to remain a good destination for anglers.
Steven Corson, a public information specialist with PGE, is quick to point out that the amount of kokanee is just one factor among several regarding the project.
“The project’s success doesn’t hinge on there being enough kokanee,” Corson said.
But, Ratliff adds, it would be too bad if the kokanee didn’t make it to the ocean.
“We are spending all this money to make a fish passage,” he said. “It would be a shame if it wasn’t a success because there wasn’t enough fish to pass through.”
Until the tower is constructed, the kokanee will continue to spawn in the Metolius River.
This year’s run will start around Oct.15, Hill said. The researchers will start collecting data before the run and after the spawning as well, to collect a full sample of the nearly 3,500 tagged salmon. They should have an accurate idea of the population size by mid-November.
Lauren Dake can be reached at 419-8074 or at ldake@bendbulletin.com.
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