Poor ocean conditions blamed for low steelhead returns

View Map

(KMVT/KSVT) — In September, the Idaho Fish and Game Commission voted to close all fall steelhead season on the Clearwater River due to low returns.

Steelhead anglers hoping for strong returns this year on the Snake River likely will be disappointed, according to the Idaho Department of Fish and Game. (Source: Roger Phillips/Idaho Fish and Game).

A portion of the Snake River, downstream from Couse Creek to the Idaho/Washington state line, was also closedin order to protect steelhead potentially coming back to Clearwater. KMVT went to the Magic Valley Regional Steelhead Hatchery to find out what's happened to the steelhead and why officials are seeing lower returns.

Following the closure on the Clearwater, there's been confusion, Magic Valley Fisheries Manager Mike Peterson said. And the most important thing is people know there's still opportunity to fish for steelhead.

"Steelhead fishing is still open," Peterson said. "There's been a lot of confusion that the season is closed statewide, because the Clearwater has a closure in effect. But most of the places people want to fish for steelhead are still open."

And low steelhead and salmon returns have been caused due to poor ocean conditions and long-term fluctuation of the Pacific Ocean, called Pacific Decadal Oscillation.

"PDO it's typically a 20 to 30 year cycle," Peterson said. "We're currently in the bottom of that cycle we hope, and we should start to climb out of it."

The PDO cycle increases the chance for marine heatwaves. In 2015, a massive marine heatwave or mass of water warmer than average, developed in the northern Pacific Ocean off the coast of Alaska. The mass of warm ocean water in 2015, was the largest in area the northern Pacific Ocean has seen in the past 40 years, according to, NOAA Fisheries, and has been commonly referred to as the "The Blob".

"2015 we had a warm water mass that moved towards the mouth of the Colombia, some people called it The Blob.," Peterson said.

The warmer than normal ocean temperatures associated with the 2015 blob resulted in the disruption of the marine ecosystem, according to NOAA Fisheries. Among those disruptions included harmful algal blooms along the West Coast. The 2015 also resulted in the movement of food sources for the salmon and steelhead further north, which has ultimately lead to lower returns for the fish.

"The further they have to travel to get their first food source the more mortality we typically experience," Peterson said.

Peterson said NOAA is studying events like The Blob and their everyday impact.

The warmer than normal ocean temperatures shifted migration routes, of several species of sea life, unusual weather patterns, and in September of this year a second marine heatwave in the Pacific arrived similar in some ways to the 2015 Blob, and has been referred to as the The Blob 2.

The full effects of these heatwaves are still being understood by scientist, and Peterson said there is some potentially good news on the horizon for next years steelhead forecast.

"Everything I've heard up to this point is we're going to be slightly above from where we're last year," Peterson said. "Hopefully those food sources that our fish depend on shift down to where they need to be."

For more information on steelhead fishing, bag limits, closures or season start and end dates, visit https://idfg.idaho.gov/fish/steelhead/rules.

Comments are posted from viewers like you and do not always reflect the views of this station. powered by Disqus