Approximately 1 million young Chinook salmon have died at the Washington Department of Fish and Wildlife’s Samish Hatchery near Burlington after a mechanical failure at 1 a.m. on Monday morning, April 29.
The salmon fry were in a pond holding 2 million young hatchery Chinook—an estimated half of which or more survived—being raised to support prey availability for Southern Resident killer whales as well as tribal and recreational salmon fisheries in the North Puget Sound Region. This Samish Hatchery program is co-managed with the Lummi Nation and Nooksack Indian Tribe and rears approximately 6 million fall Chinook.
While the loss of these Chinook is very unfortunate, and steps will be taken to prevent further incidents, WDFW says, the agency does not expect there will be significant negative impacts to orcas, Puget Sound salmon fisheries, or future hatchery operations from this loss of fry as the Samish Hatchery has seen surplus returns of Chinook in recent years.
The fish kill occurred in the early morning hours Monday due to leaves and other floating debris transported by heavy rains Sunday night clogging a rotating intake screen, resulting in low water and decreased water quality in the outdoor pond holding Chinook fry.
An alarm that should have alerted WDFW staff to respond and clean the clogged screen failed to trigger due to an issue with the electrical breaker. WDFW staff are investigating the electrical issue to prevent future failures.
The young Chinook were staged in the holding pond for mass marking, or clipping their adipose fins, before being released into the Samish River in the coming weeks. The surviving fry will be clipped and released along with the young Chinook salmon held in other ponds at the Samish Hatchery that were not affected by Monday’s incident.
More information on salmon hatcheries including production plans is available at: https://wdfw.wa.gov/fishing/management/hatcheries