Spencer Lake Ohio

A high number of fish at the Spencer Lake Wildlife Area are dead in what is called a “winterkill” and Ohio naturalists are worried few, if any, survived.

“We’ve had another long winter, we had heavy ice cover and on top of that, we had a heavy snow cover, ” said Phil Hillman, District Three fish management supervisor for the Ohio Department of Natural Resources. “As long as light can get in, there’s photosynthesis and oxygen, but light was at a bare minimum, especially by February.”

Hillman, whose office is based in Summit County, said there was a successful ice fishing season at the state park’s lake in early 2015, but it dropped off in late February. When no one was getting any bites on their lines, naturalists and anglers worried the oxygen levels might be too low to sustain the fish.

“The lake is opened up now, but unfortunately the damage has been done, ” Hillman said.

Dead fish could be seen floating in all corners of the lake this week.

Shallow, nutrient-rich lakes are more susceptible to winterkill events, Hillman said. Spencer Lake is between five and seven feet deep, but this is the first time the lake has been exposed to a major winterkill.

“We’ve had a lot of fish like bullhead and common carp found dead, and they’re tolerant of extremely low oxygen levels, so that makes us concerned it’s really bad, ” he said. “I’ve been with the division 34 years, and I can’t remember anything like this.”

Crews will head out later this spring to do a full assessment of the lake’s ecosystem.

If there was a total kill event, Hillman said there are few remedies.

“It would be nice if we could dredge out some deeper areas for the lake, ” he said. “We had the lake drained in 1986 and we carved out some areas, but we could certainly do more.”

If there are some fish that survived this year, Hillman said other actions might be considered to ensure a major kill doesn’t happen during the next severe winter freeze.

“If we still have some fish, another stop-gap measure is put some aerators in. We also could look at the dam structure and see if we can find better ways to manipulate the water level, ” he said.

There are a number of different ways a lake or pond can be aerated, such as using fountains and windmills to introduce oxygen into the water. Hillman said it was too early to consider what methods might be employed.