Rainbow trout infected with whirling disease exhibit characteristic black tail and skeletal deformities. Courtesy/UC Davis

NMGF News:

SANTA ROSA — During regular annual fish-health testing, whirling disease was unexpectedly detected in rainbow trout at Rock Lake State Fish Hatchery, a Department of Game and Fish-owned facility located two miles south of Santa Rosa.

The infection was detected at a very low level; however, out of an abundance of caution, approximately 70,000 trout in the affected portions of the hatchery will be euthanized to mitigate any risk to other fisheries in the state. This will cause a temporary reduction to stocking in many locations.

The department will continue to investigate the source of this infection and will continue to perform routine fish-health testing at state-owned fish hatcheries across the state. Whirling disease has not been detected in a New Mexico hatchery since 2007. The disease, caused by the parasite Myxobolus cerebralis, affects trout but is not known to infect other species, including humans. It has become widespread in wild trout populations across the western United States over the past 25 years and sometimes causes initial declines in trout populations. However, most populations eventually return to pre-infection levels.

For the latest stocking information, see the department’s Fishing and Stocking Report (updated weekly) or call the Information Center at 888.248.6866.