Hot Creek Hatchery in the Eastern Sierras has been able to resume the stocking of trout for recreational angling opportunities.

The hatchery was recently placed under a temporary quarantine because of the discovery of a single fish infected with Lactococcus garvieae, the bacterial strain that led to closures of three other Southern California hatcheries last year. The fish carrying the bacteria was not diseased. Following the discovery, CDFW pathologists tested over 780 fish in the hatchery raceways and did not find any other fish carrying the bacteria. This pathogen can result in significant losses of fish within a hatchery. CDFW officials, who announced the resumption of trout stocking, also said they were pleased that it wasn’t found in any other fish.

Since last year, CDFW has gained much additional information about this new pathogen and developed strategies partnering with the UC Davis Aquatic Animal Health lab to contain its spread. That work included using two new vaccines to protect fish from contracting this pathogen. Since the pathogen was discovered in just a single fish at Hot Creek Hatchery, CDFW was able to effectively monitor and contain its prevalence at the hatchery. Hot Creek Hatchery annually stocks around 600,000 trout per year across eight different waters in Inyo and Mono counties.

Additional background information on this fish pathogen can be found online at wildlife.ca.gov/Science-Institute/News/state-fisheries-biologists-continue-efforts-to-eradicate-deadly-fish-bacteria2