Thursday February 15, 2024
NOAA Fisheries —
A new genetic study shows hatchery salmon’s adaptation to their environment can lead to potentially adaptive genetic differences between hatchery and wild salmon populations in only a few generations. The collaborative research was conducted by scientists from the Alaska Fisheries Science Center, Alaska Department of Fish and Game, and Texas Christian University. It’s some of the strongest and most fine-scale evidence to date of these differences.
Pacific salmon hatcheries are used to increase harvest opportunities and supplement declining wild populations. Many hatcheries generally aim to minimize the genetic and ecological impacts of hatchery techniques during the collection, mating, and rearing of fish. These practices aim to preserve the original genetic composition of the wild population in captivity.
However, evidence suggests that hatchery rearing can inadvertently select for traits that may be disadvantageous in the wild. This could have downstream implications for native stocks, if these fish breed with wild fish when they are released. One of the goals of this study was to identify the genetic signatures of hatchery-induced adaptation, known as domestication selection. The information could aid in the development of management approaches that reduce unwanted change in hatchery-reared fish.