After seals and sea lions were spotted 70 miles up the Cowlitz River this week, anglers, lawmakers and state officials expressed concern for one of Washington’s most precious, most delicate natural resources: Chinook salmon.
Tacoma Public Utilities, which owns the Barrier Dam in Salkum where the pinnipeds (fin-footed mammals) were spotted, reported the creatures hadn’t been seen that far up the river in years.
With that news, Washington Fish and Wildlife spokesperson Benjamin Anderson told The Chronicle the agency is researching potential non-lethal deterrence actions for the Cowlitz River, especially near the Cowlitz Salmon Hatchery.
The stinky, barking swimmers have even drawn federal attention as recently as this week.
“We have been hearing about this issue!” wrote Hannah Crook, spokesperson for U.S. Rep. Marie Gluesenkamp Perez, D-Washougal. “The congresswoman thinks we need to be looking at all tools at our disposal, including lethal and nonlethal management to control pinniped populations and their effects on various salmon/fish species in our waterways.”
With Congress drafting spending bills for next year, Crook said Gluesenkamp Perez asked the Appropriations Committee to use “at least $400K” of their operating budget for more non-lethal pinniped removal technology and “no less than $1 million” for lethal removal.
According to Andrea McNamara Doyle, director of the Office of Chehalis Basin, new non-lethal technologies she learned about during the recent “Salmon Recovery Conference” in Vancouver have interesting implications for the Cowlitz River and one day, may be helpful for the Chehalis Basin.
Previous deterrent tactics used to protect salmon made the issue of pinniped predation on the fish even worse. When “acoustic deterrent devices” were introduced near salmon habitats, she said, sea lions would stay away from the noise.
However, they eventually became accustomed to the sound and, worse still, came to associate it with areas more likely to have salmon.
“Sea lions are smart, opportunistic predators, and will stay in an area as long as there is an abundant food source,” Anderson said.
In the past, agencies also tried simply moving sea lions back to warmer waters, only to find them returning to the salmon-abundant Pacific Northwest.
In a recent study by Lummi Nation Fisheries Biologist Zoe Lewis through Western Washington University, it was found that in the nine months between December 2022 and August 2021, Steller sea lions (not including their even more present cousin, California sea lions), consumed 222 tons of Chinook salmon. In data ten years earlier, the average tonnage consumed in that timeframe was 93, less than half Lewis’ findings.
The Marine Mammal Protection Act, Anderson said, is almost solely responsible for the abundance of seals and sea lions in Washington. In the Columbia Basin alone, the population has increased from fewer than 500 to more than 4,000 animals in the last decade, according to the National Oceanic and Atmospheric Administration.
