Matthew Weaver’s May 18 article on salmon returning through the Lower Snake River dams was a welcome bit of reality amidst much misleading information. The NOAA representative seemed to take a balanced approach but he missed the mark on latent mortality. NOAA in 2019 studied latent mortality and reported:

“The study found little evidence fish that go through these (fish passage) systems suffer delayed or “latent” mortality once they reach the estuary and ocean. Rather, they survive at about the same rate as fish that go through spillways and turbines.”

Another study agreed:

“… Direct tests of the theory (of dams causing latent mortality) have not found evidence to support it.”

The juvenile mortality issue is much more about predators. The 2017 study led by a NOAA scientist reported that 27 million chinook smolts are consumed each year from Alaska to California, but remarkably 23 million of those are in the Salish Sea alone.

Predation and ocean conditions are the primary drivers of the decline of chinook, and the study mentioned above showed that river systems without dams fared worse than the Snake in loss of chinook. By focusing on dam removal, the advocates are harming chinook recovery by not focusing on actions that can help restore these valuable fish.

Gerald Baron

Board Member,

Save Family Farming

Mt. Vernon, Wash.