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Idaho Fish and Game

Sockeye Exceed Expectations

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Salmon biologists expected a sockeye return last summer of about 100 fish but 257 actually made the trip back to Idaho. Compared to most years since sockeye captive breeding was established in the early 1990s, this year's return is dramatic. The 1990s saw returns in single digits. Sometimes the digit was 1 or even 0. This year's return is great news for the programs designed to save Idaho sockeye from total extinction. According to fish researchers in charge of the program, however, this run should not be interpreted as recovery of the species. To achieve replacement levels, the return would have to be about 2,000 fish. Considering the number of eggs a female sockeye lays and average survival, that's how many adult fish would be required to produce the 143,000 smolts that left Idaho in 1998, of which the lucky 257 reached adulthood and returned. Biologists expected a 0.08 percent return: that is where the 100-fish estimate originated. The return rate was actually .18 percent. To provide for replacement plus a small buffer, the return needs to be two percent or 2,860 fish. Paul Kline, manager of Idaho's sockeye program, said, "While this in no way means recovery, in terms of the program, it's great! This validates our supposition that we would not lose species productivity by taking the wild population into the hatchery. Sockeye returns were good enough this year to cause me to believe they have a good chance of rebounding when survival conditions improve." Kline provided a detailed account of what happened to this year's returning sockeye:
41 taken into captive broodstock program at Eagle Hatchery (they are here now). 120 released to Redfish Lake. 28 released to Pettit Lake. 52 released to Alturas Lake. two mortalities while holding at Sawtooth Hatchery 14 additional fish were observed in the river immediately downstream of Sawtooth Hatchery weir that did not come into the weir. The weir was pulled October 4 and those fish were allowed to swim upstream to (hopefully) Alturas or Pettit lakes.