Kokanee program hurt by low number of spawners
GRANITE, Idaho – A hatchery program used to prevent the kokanee population from collapsing in North Idaho’s Lake Pend Oreille is facing problems because of a low number of kokanee returning to spawn in Sullivan Springs Creek, officials said.
“This is shaping up to be the worst egg take we’ve ever seen,” said Bruce Thompson, assistant manager of the Idaho Department of Fish and Game’s Cabinet Gorge Hatchery.
Fish and Game and sport fishing groups have been working to restore kokanee. The landlocked sockeye salmon are the foundation of a $17 million fishery on the lake.
Thompson said the agency might have to make up for low numbers of kokanee eggs this year by asking for kokanee eggs from fish managers at Lake Whatcom in northwest Washington.
So far this year, he said, about 435,000 eggs have been collected, including 13,500 on Monday.
Since the 1980s, the department has been collecting eggs from fish trapped at the Sullivan Springs Creek spawning facility. This year’s work began on Nov. 12.
At the facility, workers collect the kokanee that have gathered in a weir, or a pen the fish are guided to by a network of metal pickets.
The kokanee are taken from the weir with a net and put in a tub of water spiked with a sedative. The eggs are squeezed from the ripe females and mixed with milt taken from males.
The eggs are then taken back across the lake to the Cabinet Gorge Hatchery, where they are raised into fish that are released into the lake.
Biologists said the program has been a key part of preventing the collapse of the kokanee population, which faces fluctuating lake levels that limit spawning success, predation by lake trout and other threats.
Thompson said the hatchery program can produce 20 million kokanee fry. Nearly three million kokanee were stocked in 2003, he said, and another 8 million in 2004.
Those fish are the ones returning to Sullivan Springs this year, but the low numbers actually making it there indicate an overabundance of predators, said Thompson.