A statement released on July 1 said lab results from University of Arizona identified a pathogen (Lactococcus garvieae) that has been linked to mortalities that hatchery staff observed since early June. The pathogen is said to be a naturally occurring bacterium that had not been found in the state before.
“Fish that are infected with L. garvieae can show symptoms like bulging eyes, lethargic or erratic swimming and increased mortality, or be asymptomatic and show no signs of infection depending on several factors, including water temperature and stress,” the statement said.
The Arizona department is working to determine the source, but warns more than two bodies of water in Arizona may have been stocked in May and June with fish carrying the bacteria.
“The current status of the department’s response to this outbreak is fluid and depends on the results of samples taken this week as well as how fish respond to treatment we are proposing to prescribe,” said Aquatic Wildlife Branch Chief Julie Carter.
The Page Springs Hatchery, about two hours north of Phoenix, Ariz., produces about 750,000 fish per year to stock Arizona’s lakes, ponds and streams, which is about 57 per cent of the stock trout in Arizona.