In the early part of the 20th century, when many Northwestern rivers were dammed, fish hatcheries provided a way to keep salmon in rivers. But now an estimated 5 billion hatchery fish are released into the Pacific every year. A collection of research released Monday highlights possible concerns about how all those hatchery fish might be impacting wild stocks. Ashley Ahearn reports.
The ocean’s a pretty big place, right? Maybe not big enough for wild salmon and hatchery salmon to share, according to some new research.
A special issue in the journal Environmental Biology of Fishes looks at how hatcheries are impacting wild fish populations. Research for the issue came from scientists around the Pacific Ocean – from Japan to California.
One of the major findings: hatchery fish may be outcompeting wild fish for food in the Bering Sea.
That area is a feeding hot spot for chum salmon – where fish that came from hatcheries mix and mingle with wild fish.
With millions more hatchery salmon arriving at the feeding grounds, there’s not enough to go around and the researchers say that contributed to a significant drop in the wild chum population.
David Noakes was the editor of the special issue. He’s a professor in the Department of Fisheries and Wildlife at Oregon State University and a senior scientist at the Oregon Hatchery Research center.
Noakes says that hatcheries are a tool but that this tool should be used with caution.
Noakes: “Because when you’re introducing large numbers of animals you need to understand that you can’t take them back. They’re living creatures and they go out there and they continue to exist and they continue to interact in the ocean.”
Hatcheries remain a major contributor to commercial salmon catches in the Northwest and Russia and Japan are increasing their hatchery outputs.
Copyright 2012 Northwest News Network