Warming rivers in the US West kills fish and imperils industry


One California river is ravaging baby salmon, while another could see an entire salmon run disappear. As adult salmon are dying in California’s rivers, fisherman who rely on them for their livelihood are voicing concern as the U.S. West experiences prolonged drought and blistering heat that raises water temperatures. This is threatening the lives of salmon fishermen from Idaho to California.

Hundreds of thousands of young salmon are dying in Northern California’s Klamath River as low water levels brought about by drought allow a parasite to thrive, devastating a Native American tribe whose diet and traditions are tied to the fish. Wildlife officials stated that the Sacramento River is experiencing a “near complete loss” of young Chinook salmon because of abnormally warm water.

A single year of young salmon can cause a crash that could have long-lasting effects on the population. It may also shorten or end the fishing season. This is a growing concern due to climate change, which continues to make the West warmer and dryer. This could have devastating effects on the commercial salmon fishing industry in California, which is worth $1.4billion.

According to Mike Hudson, a Berkeley farmer who has spent 25 years selling salmon at Berkeley farmers markets, the plummeting catch has already led to skyrocketing salmon retail prices.

Hudson stated that he considered selling his 40-foot (12 meter) boat and retiring because it was “going to get worse from there.”

Chinook salmon born in winter run are born in the Sacramento River. They then travel hundreds of miles to the Pacific where they spend three years. The winter Chinook salmon is far more resilient than the fall-run Chinook, which can survive almost exclusively due to hatchery breeding programs.

In May, federal fisheries officials warned that warmer water in Sacramento River could cause more than 80% death of baby salmon. State wildlife officials now believe that this number could rise due to the rapidly decreasing pool of cool water at Lake Shasta. Federal water managers reported this week that California’s largest reservoir has a capacity of only 35%.

John McManus (executive director, Golden State Salmon Association), which represents the fishing industry, stated that “the pain we’re going feel is a few decades from now, when no naturally spawned Salmon out in the Ocean.”

In the 1940s, Lake Shasta blocked the flow of cool mountain streams that fish spawned. The U.S. government must maintain river temperatures below 56°F (13°C) in the spawning habitat to ensure salmon eggs’ survival.

Warm water is also starting to affect older fish. Scientists have observed that some fish can die before they are able to lay eggs.

Jordan Traverso spokeswoman for California Department of Wildlife and Fish. She stated that “an extreme set of climate events is pushing our country into this crisis situation.”

The West has been grappling with a historic drought and recent heat waves worsened by climate change, stressing waterways and reservoirs that sustain millions of people and wildlife.

The state has been transporting millions of salmon from hatcheries to ocean every year, bypassing the dangerous downstream journey. Federal and state hatcheries also take extraordinary measures to protect the salmon stocks. They have a genetic bank that prevents inbreeding at hatcheries, and release them at crucial life stages when they are able to recognize the water they came from.

Environmental groups and fishermen blame water agencies for diverting too many water to farms too quickly, which could cause severe salmon deaths and push the species closer towards extinction.

“We know climate change will make years like these more common. What the agencies should do is manage for the worst case scenario,” stated Sam Mace, director of Save Our Wild Salmon. This coalition works to restore wild salmon in the Pacific Northwest.

She said, “We need to make real changes in the way rivers are managed if we want them to survive.”

California wildlife officials made a decision not to release more that 1 million Chinook salmon to the wild on the Klamath River, near the Oregon state border. Instead, they drove them to hatcheries where they could be kept until the river conditions improve.

This class of salmon is very important because it could be one of the first to return to river if plans for removing four of the six Klamath dams and restoring fish access to the upper River go according to plan.

Officials in the West are dealing with similar concerns about fish populations.

Officials in Idaho realized that endangered sockeye salmon would not make it upstream through hundreds of miles worth of warm water to reach their spawning habitat. So they filled the Snake River with cool water and then trapped the fish and transported them to hatcheries.

Environmentalists took to the courts in Portland, Oregon to attempt to get dam operators on Columbia and Snake rivers to release more water to dams that block migrating salmon. They argued that climate change and a recent heatwave were further threatening fish already at risk of extinction.

Recreational fishing is also affected by low water levels. Officials from Wyoming, Montana, Colorado, and California ask anglers not to fish in the warmest part of the day in order to reduce stress on fish that are stressed by low oxygen levels in warm waters.

Scientists believe that the California salmon population has historically rebounded from droughts. This is because the fish have evolved to withstand the Mediterranean climate and have benefited from the rainy and wet years. However, prolonged droughts could result in the extinction of some salmon runs.

Andrew Rypel, a University of California, Davis fish ecologist, said, “We’re at a point where I don’t think drought is an appropriate term to describe the situation.” He stated that the West is moving to a more water-scarce world.

Hudson, the fisherman, stated that he used spend days at sea during the salmon season, and could catch 100 fish per hour.

He said that he was fortunate to have 80 animals to sell at the market this year.

Hudson stated, “Retirement would be smart but I can’t help myself because these fish have been so kind to us all these years,” Hudson added. “I cannot just walk away.”