About 200 spring-run salmon may die before they spawn

About 200 spring-run salmon, swimming in Butte Creek just south of Chico, will apparently die this summer before they can spawn.

Action to try to save the big fish has been suggested.

However, Tracy McReynolds, a fisheries biologist with the state Department of Fish and Game, said her agency has decided it's best to leave the salmon alone.

The salmon in lower Butte Creek are certainly stressed, and they may be diseased, she said. If that's the case, encouraging them to join the rest of the run farther upstream, may infect healthy fish.

It seems best to let nature take its course, she said. Butte Creek's spring-run salmon are a treasured resource. They're designated a threatened species, for one thing. But also, Butte Creek is one of the few places in the Sacramento Valley where large numbers of the fish still spawn naturally instead of in fish hatcheries.

The salmon live for three years. They hatch in the late fall or winter in the upper parts of Butte Creek. In the spring, the baby fish migrate downstream to the Sacramento River and then on to the San Francisco Bay and the ocean. Three years later, in the spring, they return to Butte Creek.

By this time of year, the salmon that returned should be in deep, cold pools in far up the canyon. Right now, in fact, thousands of them can be found there. They'll wait out the hot summer and in the fall, spawn and die.

This year, for whatever reason, some of the salmon haven't gone into the canyon. They're swimming around in the creek south of Highway 99.

If they don't move up into the canyon, where there's colder water, they will die before they can spawn in the fall, McReynolds said. High water temperatures will kill them.

Allen Harthorn, executive director of Friends of Butte Creek, said he'd like to see something done to save the salmon in the lower part of the creek.

Harthorn and McReynolds both said the salmon might move upstream on their own, given some more time.

But McReynolds said the fish are already stressed from being in water that's too warm, and they may have become diseased. It could be a mistake to encourage them to join the rest of the run, she said.

Harthorn said there's no evidence the fish are diseased.

McReynolds said her agency's decision not to try to get the remaining salmon to go farther upstream is based on a couple of things.

One is the health issue. The other is it appears there are plenty of spring-run salmon in the upper part of the creek already this year.

Harthorn, whose organization seeks greater environmental protection for the Butte Creek watershed, said he questions the notion that there are "enough" spring-run salmon in the upper part of the creek.

"How can it be that there's too many fish, yet we can't fish for them?" he said.

The spring run of salmon on Butte Creek used to be huge. But by the 1970s, it had dwindled to just a few fish in some years. That was apparently because of low flows, dams that blocked the fishes' way, unscreened diversion ditches, development and other human activities. Then efforts were begun to restore the run. Dams were removed. Diversions were screened. Harthorn, who lives in Butte Creek Canyon, said he thinks the most helpful changes were adding more water to the creek. In the 1970s, the creek, in the summer, was pretty much a network of pools connected by trickles of water.

In the 1970s, PG&E had to release 10 cubic feet per second of water into the creek above the Centerville Powerhouse. In the 1980s, that was doubled, to 20 cfs. The big change, according to Harthorn came in 1992, when the federal government ordered the power company to release 40 cfs to help the fish.

"Since that flow was increased, we've seen remarkable returns," Harthorn said. Removing dams and fixing fish ladders, which occurred later, helped, too.

In 1992, the total number of fish that spawned in the creek was 750, he said. Three years later, 7,500 fish spawned.

The size of this year's run won't be estimated until after the fish spawn in the fall, but Harthorn said there may be 15,000 salmon in upper Butte Creek right now, waiting for the time to spawn.

Limited fishing for spring-run salmon used to be allowed on Butte Creek, but it was discontinued in 1994. Harthorn, who is an angler, looks forward to the day it will be allowed again. He said better research needs to be done on Butte Creek's spring-run salmon. More information should lead to better management of the creek to benefit the fish.

There are unanswered questions, he said. For example, while Fish and Game insists that the spring-run fish can't survive in warmer water, he's heard anecdotal evidence to the contrary.

Although McReynolds denies it, he said he believes it's possible that some of the 200 fish downstream from Highway 99 might survive the summer and spawn in the fall.

Reprinted from the June 27, 2007 Enterprise-Record