On June 1, Idaho Fish and Game staff at Hagerman State Fish Hatchery euthanized about 188,000 young rainbow trout after the fish contracted a viral disease called infectious hematopoietic necrosis (IHN). There are no treatments to cure fish with IHN, so euthanasia is the best way to stop an outbreak and prevent the virus from spreading throughout the hatchery.
The euthanized fish were about 2 inches long and slated to be stocked as 10-inch catchable-sized fish in the summer of 2023. The Hagerman State Hatchery is still expected to release the 1.8 million rainbow trout currently being reared at the facility, and the Hayspur Fish Hatchery is able to provide additional juvenile rainbow trout so the incident will not result in a net loss of production. These replacement fish are still expected to be released in 2023, about 6 to 8 weeks later than called for in the original stocking schedule.
Hagerman Hatchery is one of 20 fish hatcheries Fish and Games owns or manages across the state that produce and stock over 30 million fish in rivers, lakes and reservoirs every year.