Mystery of the missing salmon

Unsolved mystery
So what happened to the fish?

Were they victimized by the wily sea lions that have discovered how to climb fish ladders at the Bonneville Dam, sitting there all day and devouring the unfortunate fish that try to swim past? Has there been some significant change in ocean conditions that have killed thousands of fish? Or is there some secret black market downriver that’s catching all the fish as they try to swim up the river?

Sea lions are easy targets of the public and the government fish managers, who have begun to blast fireworks on the Bonneville Dam fish ladders where many lions have taken up residence. But even the hundreds of sea lions that now live around the dam couldn’t eat nearly enough fish to account for the tiny run.

The fish market is also closely monitored by government regulatory agencies, so a massive black market is highly unlikely.

Scientists say they haven’t seen any evidence of a dramatic change in ocean conditions that could cause so many fish to die, but that could be a likely problem, according to Steve Williams, the assistant director of the fish program at the Oregon Department of Fish and Wildlife.

Such changes could include increased predation of the fish, or a change in water temperatures. Williams said scientists have not been able to pinpoint what changes have occurred that have hurt fish populations.

Williams noted that the annual springtime smelt fish run up the river was also nearly nonexistent this season. Smelt runs have not in years past been accurate predictors of salmon runs up the river, but both fish would be susceptible to altered ocean conditions, so the same problem could be to blame for reduced populations of both fish.

Most people involved have established their own theories. Ball, the fisherman, said he suspects the salmon have been tricked by lower water levels caused by last summer’s drought into delaying their run up the river. He said he also thinks the sea lions may have quite a bit to do with it.

Ellis and Williams both agree that none of these problems individually should take all the blame. If anything, the low numbers of salmon are the result of a number of factors influencing their ability to swim past the Bonneville Dam to their upstream spawning grounds.

Room for optimism
Williams said that despite the dismal numbers and initial panic, he and others are now looking at the salmon run with "slight optimism."

"Last week we were definitely in crisis mode," he said. But the increase in the number of fish making their way upstream is cause for optimism, he said, and he expects the run this year to at least hit the minimum expectation of 70,000 fish.

Williams also said that the commercial and sport fisheries might, if the count continues to trend upward, be opened again soon. He said fish managers are evaluating the necessity of the closure on a weekly basis, and could decide as soon as next week that salmon numbers are sufficient to warrant it reopening.

Even if the fishery were to reopen soon, however, it would be too late for many of those people dependent on the fish. Most of the Indian celebrations are done for the season, and most of the commercial fishermen have departed the salmon fishery, looking for greener pastures in other Pacific Northwest regions.

"They’re hoping, with a great, fervent hope, that the Alaska season will bring some revenues to them and their families," said Waldman, of Salmon for All. Even if the river were reopened to the fishermen next week, they’ve already departed north and couldn’t be repositioned for the Chinook catch.

Scientists are careful to note that the fish count continues through early June, but say that even if it turned out that the run was simply delayed this year, or even if daily counts jumped into the thousands, this year’s run still won’t come close to the numbers initially predicted.

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