Thursday, July 26, 2012

Hatchery salmon threaten wild populations, scientists say

All the citizens and organizations writing the Oregon Department of Fish and Wildlife out of concern over the high percentage of hatchery salmon allowed on the Chetco are to be congratulated for standing up for the river's exceptional wild salmon populations. Here's an excerpt from a new post, "Hatchery salmon threaten wild populations, scientist say," on Breaking Waves, Oregon Sea Grant's news blog that provides even more science supporting the need to reduce hatchery supplementation:

A newly published collection of more than 20 studies by leading university scientists and government fishery researchers in Alaska, British Columbia, Washington, Oregon, California, Russia and Japan provides mounting evidence that salmon raised in man-made hatcheries can harm wild salmon through competition for food and habitat. 
“The genetic effects of mixing hatchery fish with wild populations have been well-documented,” says journal editor David Noakes* from Oregon State University. “But until now the ecological effects were largely hypothetical. Now we know the problems are real and warrant more attention from fisheries managers.” 
The research volume, published in the May issue of Environmental Biology of Fishes, brings together 23 peer-reviewed, independent studies carried out across the entire range of Pacific salmon, including some of the first studies describing the impact of hatcheries on wild salmon populations in Japan and Russia. 
The studies provide new evidence that fast-growing hatchery fish compete with wild fish for food and habitat in the ocean as well as in the rivers where they return to spawn. The research also raises questions about whether the ocean can supply enough food to support future increases in hatchery fish while still sustaining the productivity of wild salmon.
Read the whole post at Breaking Waves or go directly to the full article on Science Blog.