This year has had one of the biggest salmon runs of all time for the Pacific Northwest (PNW). There were over 34 million salmon in the British Columbia river system alone, compared to last year’s count of only two million.

The sockeye salmons swim upstream in the Adams River in the Province of British Columbia, Canada, Oct. 7, 2010. As many as 2.5 million sockeye salmons are expected to be flooding into the Adams river this year, which is supposed to be the biggest sockeye run in a century.?[Xinhua]

The problem with this resurgence is that much of the new numbers come from hatchery-raised salmon, which have created increased competition for the threatened wild salmon species. According to a recent study in the journal Marine and Coastal Fisheries, the overcrowding of salmon in the PNW is nearing capacity for the ecosystem. Once that limit is crossed, there will not be enough resources to sustain such great numbers.

Bruce Barcott, journalist for Outside Magazine, National Geographic, and other publications, has been studying in depth the current and past issues with PNW salmon. He believes that over twenty percent of all the fish were raised in hatcheries. These fish out-compete the threatened wild salmon for food.

Industrial salmon hatcheries have gone into overdrive over the past few decades. In 1970, PNW hatcheries released about 500 million salmon into the Pacific. However, by 2008, that number skyrocketed to five billion. These fish were raised in an industrial facility from eggs and released as fry — baby fish which have absorbed their yoke sac and are able to hunt for their own food.

Most of the species released around the Pacific Rim were pink or chum. In fact, there are more chum salmon in the Pacific from Japanese hatcheries than the wild chum salmon.

This would not be so terrible if not for the nature of the hatchery-raised salmon. They come from stock that has less diverse DNA, making them genetically unfit for the long-term survival of the species. It is akin to inbreeding, which leads to genetic dysfunction. The hatchery salmon are in a word, dumber, than their wild counterparts.

According to scientists, Ray Hilborn of the University of Washington, and Doug Eggers of the Alaska Department of Fish and Game, the recent boom in the salmon population would have happened even without the hatcheries because of favorable ocean conditions in the North Pacific. Then those massive salmon runs would have been all healthy wild salmon.

"What we did with hatcheries was take a free way of making fish, and turn it into an expensive way of making fish," says Hilborn. "Ecosystems have limits. And we're seeing very clear signs that the North Pacific Ocean is reaching its limit for salmon."