Jenna Ladd |June 8, 2017
A fish kill has been reported at Casey Lake in Tama County. More than 1,000 black crappies were reported dead at the Hickory Hills Park Lake yesterday. Crappies are a North American freshwater sunfish that are indigenous to Iowa. Fish kills can be caused a number of factors including pesticide contamination, high temperatures, algal blooms and more.
“When we get calls about one species of dead fish during the spawning season, it is usually caused by spawning stress,” said Dan Kirby, fisheries management biologist for the Iowa Department of Natural Resources (DNR). Like many freshwater fish, crappies move closer to the shoreline to spawn in the late spring and early summer. Spawning activities require fish to expend a lot of energy, leaving them susceptible to infections and illness. It is common for spawning fish to sustain abrasions from jagged rocks and debris at the water’s edge. These cuts and scrapes are vulnerable to infection that can cause death. Typically, spawning stress fish kills occur slowly over the course of weeks. It is unclear how long the fish at Casey Lake were piling up near shore.
“Fish surveys conducted this week on Casey Lake showed that largemouth bass and bluegills are doing well, and black crappies are abundant,” Kirby added.
Iowa DNR encourages residents to call their 24-hour phone line at 515-725-8694 if they notice dead fish accumulating in lakes or rivers.