CAZENOVIA — Last week, the New York State Department of Environmental Conservation (DEC) received several reports of deceased fish in the north end of Cazenovia Lake.

Upon inspection, Dave Miller, president of the Cazenovia Lake Association, determined that there were approximately a hundred dead fish, most of which appeared to be small bluegill and other sunfish/panfish.

According to Kerry McElroy, public participation specialist in the DEC Office of Communication Services, observations from DEC’s fisheries experts aligned with reports that the fish were in varying states of decay, the rate of which is typically slowed by cold water temperatures.

The DEC determined that the fish likely died due to a winterkill event, “a common occurrence during spring ice melt, which can be observed in waterbodies across the state.”

Winterkill is a fish mortality event generally caused by a depletion of dissolved oxygen (DO).

According to Thad Yorks, program director of biology and environmental biology at Cazenovia College, low DO levels can result from extended ice coverage, which “short-circuits” the diffusion of O2 from the air into the water, and snow accumulation on top of the ice, which slows in-lake photosynthesis, thereby slowing the production of DO beneath the ice.

If new, freshly dead or dying fish appear, contact DEC’s regional fisheries office at [email protected] or 607-753-3095.