Fish Sticks
Well-known member
—-The impacts of rearing and stocking non-native fish into watersheds where they don’t belong are well understood: undue competition for limited resources, hybridization, predation — the list goes on. In the American West, we’ve seen how introduced brook trout outcompete native cutthroat trout and eventually take over; or how rainbow trout mingle with native cutthroat trout during the spring spawn and produce a fertile hybrid that slowly eats away at native fish genetics.
But even attempts to boost fish native stocks by raising genetically “appropriate” native fish and then releasing them into watersheds where they are native might be causing harm to native fish born and reared in the wild. According to a new study led by Akira Terui, a biology professor at the University of North Carolina at Greensboro, efforts to boost fish populations by introducing captive-bred fish of the same species into the wild has a negative effect on the native fish population.
The new study backs up assertions that, in the United States, efforts to boost, enhance or rebuild stocks of anadromous fish, like steelhead and salmon, by rearing and releasing native fish are generally fruitless and, in some cases, inflict more harm than good.
——“Stream fish communities showed greater temporal fluctuations and fewer taxonomic richness in rivers with the intensive release of hatchery salmon—a major fishery resource worldwide,” the study reads. “Our findings alarm that the current overreliance on intentional release may accelerate global biodiversity loss with undesired consequences for the provisioning of ecosystem services.”
But even attempts to boost fish native stocks by raising genetically “appropriate” native fish and then releasing them into watersheds where they are native might be causing harm to native fish born and reared in the wild. According to a new study led by Akira Terui, a biology professor at the University of North Carolina at Greensboro, efforts to boost fish populations by introducing captive-bred fish of the same species into the wild has a negative effect on the native fish population.
The new study backs up assertions that, in the United States, efforts to boost, enhance or rebuild stocks of anadromous fish, like steelhead and salmon, by rearing and releasing native fish are generally fruitless and, in some cases, inflict more harm than good.
——“Stream fish communities showed greater temporal fluctuations and fewer taxonomic richness in rivers with the intensive release of hatchery salmon—a major fishery resource worldwide,” the study reads. “Our findings alarm that the current overreliance on intentional release may accelerate global biodiversity loss with undesired consequences for the provisioning of ecosystem services.”
More evidence that releasing hatchery-reared native fish is harmful
The impacts of rearing and stocking non-native fish into watersheds where they don’t belong are well understood: undue competition for limited resources, hybridization, predation — the list goes on. In the American West, we’ve seen how introduced brook trout outcompete native cutthroat trout and...
www.hatchmag.com
