Conservation Alert: Increasing competition between wild and hatchery salmon in the North Pacific.
A recent study published in the journal Marine and Coastal Fisheries found that pink, chum and sockeye salmon are at historically high levels in the North Pacific Ocean, but the ocean is getting overcrowded with salmon. The trends indicate that competition between wild and hatchery salmon will increase due to increasing hatchery releases combined with periodic shifts in ocean productivity?
The release of juvenile hatchery salmon has skyrocketed to about 5 billion fish per year, and the study found that more than one in five — originate in hatcheries. For populations in some regions, the percentage is significantly higher. In Asia, 76 per cent of all adult chum salmon from 1990 to 2005 came from salmon hatcheries. Studies on ecological interactions between hatchery and wild fish, the focus of last spring’s State of the Salmon’s conference, have shown that hatchery-bred salmon can compete with endangered wild runs for limited food resources, potentially hampering their recovery.
The study recommended that North Pacific managers should engage in serious discussions on how best to share common food resources in the ocean. Otherwise as future areas of ocean habitat shrink from climate change, hatchery fish may dominate the ocean and contribute to a perfect storm for wild salmon — putting them up against higher competition, additional overfishing pressures, and lower genetic diversity of wild salmon populations.
A full copy of the report is currently available online at American Fisheries Society Journals.