A number of KLA members have reported dead fish washing up on their shorelines over the last 1-2 weeks. We have been in close contact with officials at the NYS DEC.  They were on Keuka Lake on June 18 and were able to procure some freshly deceased fish which were taken to Cornell University for testing.  Studies showed the fish were infected with Saprolegnia parasitica, a water mold that is ubiquitous in freshwater bodies.  They are opportunists, meaning they generally do not harm healthy fish, but can infect and kill fish that are under significant physiological stress.

Keuka Lake fish are thought to be under considerable stress at this time. Triggers include:

• Temperature shocks. Rapid warming stresses fish and promotes mold spore release. On Keuka Lake, per our website, lake temperature was 55 degrees on June 2 and 68 degrees on June 14.

This is likely the major driver for the fish loss.

• Spawning events. Spawning depletes energy, compromises immunity, causes minor scale injuries and slime layer disruptions, and is associated with decreased food intake. This makes fish an easier target for mold attack.

Abundant rains this spring brought excessive sediments and nutrients into the lake. This creates a permissive environment for the water mold and can further stress the fish as they spawn in shallower, warmer, more turbid waters. Furthermore, both warmer water and turbidity can decrease dissolved O2 in the water, adding more stress. It is thought that this loss of fish will improve over the next few days/weeks as fish recover from spawning and accommodate to the warmer temperatures.  This is the pattern we noticed last year.

Recommendations for shoreline cleanup:

• Wear protection, such as gloves, masks, safety glasses
• Use a shovel to move the dead fish
• Dispose by bagging the fish in heavy-duty garbage bags and placing in household trash bins

Significant fish loss that lingers beyond later June should be reported back to the KLA. We will continue to monitor this situation and keep our membership posted.