Thursday 31 July 2014

Climate change

Salmon Are Dying In The Salmon River Because The Water’s Too Warm



28 July, 2014

Fifty-four adult and hundreds of young fish have died in California’s Salmon River, due to low water flows and warmer-than-usual temperatures.

A population assessment for Chinook salmon and Steelhead in the river found
300 to 600 juvenile fish — mainly Chinook — have died, prompting concerns over further reductions in the species’ populations as California’s drought persists. The fish are dying before they get the chance to spawn, due to drought and decreased snowpack-fueled low water levels. Right now, the river is running at 181 cubic feet per second — far below the average flow of 438 cubic feet per second and close to the record low of 110 cubic feet.

We’re all on alert,” California Department of Fish and Wildlife environmental scientist Sara Borok told the Times-Standard. “We don’t to want lose this year’s spring run. There’s not a whole lot we can do other than have more rain dances.”

The population assessment was done by the Klamath Basin Monitoring Program’s Klamath Fish Health Assessment Team, a group of volunteers from state agencies, local tribes and environmental groups. Craig Tucker, Klamath River Campaign Coordinator for the Karuk Tribe, said the Salmon River is a crucial waterway for young Chinook salmon, so warmer-than-usual water in the river doesn’t bode well for the fish.

This year, the drought is just having a horrific toll on these fish,” he said. “They are really struggling to find those cold water refuges they need to survive.”

Luckily, despite the losses, the Chinook population in California hasn’t taken too much of a hit. But the Salmon River losses aren’t the only challenges California’s fisheries — natural and managed — have had to deal with during this year’s severe drought. In June, two fisheries were forced to evacuate their young fish into two waterways months before they usually do, amid fears that, by the middle of the summer, water temperatures in the hatcheries would be too high for the fish to survive.

Though their early release was meant to give the fish a better chance of survival, Peter Moyle, professor and associate director of the Center for Watershed Sciences at the University of California, Davis, told ThinkProgress in June that most of the fish released early — especially the steelhead — likely won’t survive.

These fish are very unlikely to make it,” Moyle said of the steelhead. “They’re releasing 450,000 fish all at once into a river which is full of other fish, including other predators. These fish are hatchery fish — they’ve never experienced anything but life in a cement trough — so they are ill-equipped for surviving in the wild.”

The drought has also forced the state of California to ship millions young Chinook salmon by truck to the Pacific Ocean, bypassing the streams that the young smolts usually travel through because of their warm, low water. California has always shipped some of its young salmon by truck to the Pacific, but this year, it was forced to ship about 50 percent more fish than usual.


Right now, 100 percent of California is in the most severe rankings of drought, with 81 percent of the state in the extreme to exceptional drought range. California Gov. Jerry Brown linked the state’s extreme drought and wildfires to climate change earlier this year, saying that though the state was trying to “deal with nature as best we can” humanity was “on a collision course with nature” due to climate change.

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