Fish winterkill may be a common occurrence in Ohio lakes and ponds this spring.
Ohio experienced a very harsh, cold, and long winter in 2014-15. Thankfully, the thaw has finally begun in the Buckeye State, but fish winterkill is likely to be common this spring. The Ohio Department of Natural Resources (ODNR) is warning anglers and pond owners of this increased likelihood of fish winterkill.
According to the ODNR,
Winterkills are caused when persistent ice forms a surface barrier between water and air that prevents circulation of oxygen and blocks sunlight. If these conditions continue long enough, the oxygen fish need to survive may be depleted and result in some or all of them suffocating.
The Fish Winterkill Process
This phenomenon is most common in shallow and small ponds. A fish winterkill is easily identified when dead fish are found floating along the shoreline once all the ice has melted. This is generally more likely to happen in the northern reaches of the state, but this past winter was severe enough to potentially affect ponds across the state.
Reducing vegetation found in a pond is the best way to help avoid a fish winterkill. There are several strategies that you can use to achieve this goal. The bank of any pond should be dug at a 3:1 ratio. This means that for every three feet of distance, the pond should drop by one foot. A pond should also have a depth of 10-12 feet in at least 25 percent of the total area.
Keeping grass clippings from falling into the pond and avoiding the use of fertilizers within 50 feet of the bank will also help to reduce the possibility of a fish winterkill.
Perhaps the best way to avoid a fish winterkill happening in your pond is to add an aeration system to the water. There are many different options available to fit any budget. A simple bubbler will help prevent ice from forming on the pond in the first place.
Farm ponds are an important part of the ecosystem and proper watershed management is important. To learn more about avoiding a fish winterkill and other pond management techniques, click here.