Researchers Work with Salmon DNA to Save FishAssociated Press, Times-News - October 25, 2002
STANLEY -- Scientists working to restore sockeye salmon runs to Red Fish Lake say DNA is key to bringing the fish back.
University of Idaho researchers at the Center for Salmonid and Freshwater Species at Risk use gene-sequencing equipment to ensure genetic diversity when the fish spawn.
When an adult fish returns to the hatchery, it is tested to determine its genetic background. Adults at the hatchery are then spawned to create the broadest possible gene pool.
The cooperative effort by the Shoshone-Bannock Tribes, Idaho Fish and Game, National Marine Fisheries Service and the University of Idaho to restore the Redfish Lake sockeye began with the offspring of six females. The run was the first to be listed as an endangered species in 1991.
Center director Madison Powell said the six maternal lines have been reduced to three because offspring from the other lines did not survive the migration from the ocean. He said fewer than one in 1,000 young sockeye that leave Idaho will ever return.
"The program as it exists now is essentially a gene-rescue program," Powell said.
This fall more than 140 adult sockeye are expected to return to Redfish Lake to spawn. That number is higher than the total number of fish counted the lake during the entire decade of the 1990s.
In 1992 only one sockeye, a male dubbed Lonesome Larry, returned to spawn. In other years no fish returned. Researchers collected and froze sperm from the returning males to be used to fertilize eggs in future years.
"While we are not out of the woods yet, significant strides have been made," Gov. Dirk Kempthorne said during a recent visit to the lake. "I can say with relative certainty that without this intervention the Idaho sockeye would now be extinct.
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