Baker Lake sockeye make record return - Human efforts to save salmon include 'fish taxis,' 'gulpers'
CONCRETE - Sockeye salmon have returned to spawn at Baker Lake in the best run since wildlife officials started keeping track - good news for a species feared to be on the brink of extinction 20 years ago.
Salmon recovery experts stop short of saying they've outwitted a species known for its complex instincts and migratory odysseys. But the run - 20,188 and counting - has boosted the hopes of fish biologists who believe human intervention, no matter how low-tech or non-flashy, is working.
The previous record was a return of 15,991 sockeye in 1994, fish biologists say. Six of the top runs in Baker Lake sockeye-count history, since 1926, have occurred in the past 10 years.
"We are getting smarter about helping out the sockeye," said Roger Thompson, spokesman for Puget Sound Energy, which operates two dams on the Baker River in northwestern Washington.
Key recovery efforts include a trap to collect adult fish headed upriver, "fish taxis," a man-made spawning beach and a "gulper" - a contraption that captures sockeye, mostly at the smolting stage, when they're 4 to 5 inches long. The gulper's pumps and pipes simulate water currents, which help convince sockeye they're on the right way out to get to the ocean.
"The guide nets are like big catcher's mitts - nothing gets past them," said Cary Feldmann, a fish biologist who has studied Baker Lake sockeye for 25 years.
"Fish taxis" are trucks loaded with high-capacity water tanks to transport adult sockeye to salmon spawning areas, sockeye fry to Baker Lake above the dams, and smolts or juveniles back down below the dams. The fish never leave water, swimming from traps to funnel-shaped "hoppers," raised by cables onto the taxi tanks.
'It was amazing'
Skip Ritchey, a longtime Puget Sound Energy maintenance worker who drove taxis this summer, said during the run's peak about a month ago, taxis were carrying 1,200 sockeye a day, seven days a week.
"We were going from dawn to dusk," Ritchey said. "It was amazing. If it wasn't for the taxis, the fish would hit a dead end (at the adult trap); they'd die and never spawn."
Experts say this year's record run is likely related to another record: in 2001, the number of juveniles leaving Baker Lake hit 194,000.
While biologists are quick to note that ocean conditions and other factors can make a big difference in the up-and-down cycles of fish runs, they are encouraged that numbers are increasing beyond the historical average of about 3,000.
Even relatively "low" years - about 5,000 in 2001 and 4,000 last year - show upward trends, experts say.
"We are building momentum," Feldmann said. "People
may think some of this, like the gulper, looks pretty decrepit, but
it works. We've had a lot of bright people thinking outside the box
to solve the problem. We think others can learn from this."
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