From the images shared, these appear to be Philemona, a freshwater parasite. Philomena is a food quality concern but is Not considered a human health concern. With proper preparation, the salmon is safe to eat.

These worms, present in halibut, cod, salmon and other saltwater fish, are increasing. If the worms are well frozen or cooked, they don’t pose a health threat.

Researchers say climate change is playing a big role in the collapse, which has left thousands of people along the river without the salmon they depend on. 

Chinook (king) and chum are the major salmon species on the Yukon and Kuskokwim. They’ve been at historically low numbers in both rivers for years. The coho (silver) returns have also dropped.This will be the fourth year subsistence fishing has been closed or severely restricted on both rivers. The region is bracing for another dismal subsistence harvest.

Alaska researchers will continue a controversial study this year on a parasite in Yukon River chinook salmon that requires killing hundreds of fish, a move that’s drawn sharp criticism from Canadian experts. 

About 10% of our catch during dip net fishing at mouth of Kenai River was harboring these worms.

Dead chum salmon are lining the banks of one of the Yukon River’s largest tributaries. Koyukuk River residents and scientists alike suspect the deaths are

Subsistence families along the Kuskokwim River are cutting open fish to find white balls or white streaks deforming the meat.

A considerable number of the herring catch that’s been landed in recent days has been found to be infected. As such, almost all of it will be incinerated. Note, according to Fisheries Information and Resource System (FIRMS) the infection rate of herring with Ichthyophonus in Iceland was estimated to be 32% in the in the winter 2008/2009.

With a sickening thud, another hefty and handsome salmon lands in the waste barrel, headed for the dogs .