Alaska's largest sockeye salmon run exceeded expectations in numbers but featured the smallest fish on record, posing challenges for commercial harvest.

The sockeye salmon are coming back smaller for the Newhalen River and Iliamna Lake, plus not a thick as they once did when I was younger.

"My husband and I have been dipnetting on the Kasilof since 2014. This year we noticed more small fish than usual and all but ~5 of the 35 fish we caught had parasites."

The shrinking of chinook, sockeye, coho and chum salmon has a negative impact on the number of eggs fish lay, but smaller body sizes also mean fewer meals, fewer commercial fishing dollars and fewer nutrients transported into rivers every year.

As of Friday afternoon, the sockeye escapement in the Chignik salmon fishery was less than half of what it usually is this time of the year.

Warming waters have reduced the harvest of Alaska's prized Copper River salmon to just a fraction of last year's harvest, Alaska biologists say.

Sockeye are smaller in size and fewer in number this year than in recent years.

Biologists blame the Blob of warm water in the Gulf of Alaska for poor sockeye returns that also led to the second lowest commercial harvest in 50 years.