Half of Columbia River sockeye salmon dying due to hot water

More than a quarter million sockeye salmon returning from the ocean to spawn are either dead or dying in the Columbia River and its tributaries due to warming water temperatures.

Federal and state fisheries biologists say the warm water is lethal for the cold-water species and is wiping out at least half of this year's return of 500,000 fish.

"We had a really big migration of sockeye," said Ritchie Graves of the National Oceanic and Atmospheric Administration. "The thing that really hurts is we're going to lose a majority of those fish."

He said up to 80 percent of the population could ultimately perish.

Elsewhere in the region, state fisheries biologists in Oregon say more than 100 spring chinook died earlier this month in the Middle Fork of the John Day River when water temperatures hit the mid-70s. Oregon and Washington state have both enacted sport fishing closures due to warm water, and sturgeon fishing in the Columbia River upstream of Bonneville Dam has been halted after some of the large, bottom dwelling fish started turning up dead.

Efforts by management teams to cool flows below 70 degrees by releasing cold water from selected reservoirs are continuing in an attempt to prevent similar fish kills among chinook salmon and steelhead, which migrate later in the summer from the Pacific Ocean.

The fish become stressed at temperatures above 68 degrees and stop migrating at 74 degrees. Much of the basin is at or over 70 degrees due to a combination that experts attribute to drought and record heat in June.

"The tributaries are running hot," Graves said. "A lot of those are in the 76-degree range."

In Idaho, an emergency declaration earlier this month allowed state fisheries managers to capture endangered Snake River sockeye destined for central Idaho and take them to a hatchery to recover in cooler water. Of the 4,000 fish that passed Bonneville Dam on the Columbia River, less than a fourth made it to Ice Harbor Dam on the Snake River. An average year is 70 percent.

"Right now it's grim for adult sockeye," said Russ Kiefer of the Idaho Department of Fish and Game. He said sockeye will often pull into tributary rivers in search of cooler water, but aren't finding much relief.

"They're running out of energy reserves, and we're getting a lot of reports of fish dead and dying," he said.

Thirteen species of salmon and steelhead are listed as endangered or threatened in the Columbia River basin.

Don Campton of the U.S. Fish and Wildlife Service said fish congregating in confined areas trying to find cool water makes them a target for pathogens.

"When temperatures get warm, it does stress the fish out and they become susceptible to disease," he said.

Graves said that this year's flow in the Columbia River is among the lowest in the last 60 years. But he said the system has experienced similar low flows without the lethal water temperatures. He said the difference this year has been prolonged hot temperatures, sometimes more than 100 degrees, in the interior part of the basin.

"The flow is abnormally low, but on top of that we've had superhot temperatures for a really long time," he said.


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Stress from heat, drought on fish spurs push to reduce kills

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Jul 27, 2015
Another coal mine canary.

When are we going to wake up and ditch Filthy Fuels?

Jul 27, 2015
Another coal mine canary.

When are we going to wake up and ditch Filthy Fuels?


Weather =/= Climate

Jul 27, 2015
"Weather =/= Climate"
-------------------------

It does if it's permanent.

Jul 27, 2015
The warm weather in the Northwest this year is independent of climate change.

http://cliffmass....ion.html
http://cliffmass....oes.html
http://cliffmass....est.html

Jul 27, 2015
@dbre

"Below are some of the impacts that are currently visible throughout the U.S. and will continue to affect these regions"

"Northwest. Changes in the timing of streamflow reduce water supplies for competing demands. Sea level rise, erosion, inundation, risks to infrastructure, and increasing ocean acidity pose major threats. Increasing wildfire, insect outbreaks, and tree diseases are causing widespread tree die-off."
http://climate.na...effects/

NASA or a denier with a blog?

I'll choose NASA everytime.


Jul 27, 2015
And the other half will evolve to create a new more resistant and vibrant species. This process is called 'Evolution' or otherwise known as "Survival of the fittest". Been going on for millions of years and is not going to stop because some water got warmer.

Jul 28, 2015
It's not evolution, it's mass extinction, you moron. Evolution takes time. There has to BE survivors of the specie.

Extinction just takes an immediate disaster.

Jul 29, 2015
Another canary in the coal mine is right, but it's the hot particles of Fukushima and not AGWite hot water bullshit.

Jul 29, 2015
Another canary in the coal mine is right, but it's the hot particles of Fukushima and not AGWite hot water bullshit.


I didn't think you could double down on craziness but you have.

Jul 29, 2015
Hmm... I wonder how they survived the mega-droughts of the past.

Jul 30, 2015
Efforts by management teams to cool flows below 70 degrees by releasing cold water from selected reservoirs....

Yep it's all GloBULL warming.
The fact that idiots have disrupted the natural flow has nothing to do with it.

Jul 30, 2015
If our basis for contentment is a lack of change, we're going to be an unhappy lot indeed.

It's not evolution, it's mass extinction, you moron. Evolution takes time. There has to BE survivors of the specie.

Extinction just takes an immediate disaster.


If it weren't for the extinction of previous species, you'd never have existed. We aren't in control... embrace it or be miserable.

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