- The Pennsylvania Fish and Boat Commission notified the Pennsylvania Department of Environmental Protection (DEP) July 24 of a fish kill on a local lake.
Lake Ariel, located in Lake Township, had at least 10,000 fish die that morning.
According to published reports, Fish and Boat Commission press secretary Eric Levis said in an statement that "there was a fish kill of approximately 9,000 minnows and other small fish and about 1,000 game fish such as bass, yellow perch and bluegill." Levis added that the commission is "still investigating the cause of the kill."
DEP Regional Spokesperson Colleen Connolly said Monday that DEP is "just assisting the Fish and Boat Commission" with the ongoing investigation to determine what could have caused the fish kill.
Walt Buckman, conservation officer for the Pennsylvania Fish and Boat Commission, said that the fish kill event is currently "under investigation." No updates were available as to the progress of the investigation as of press time.
What causes a fish kill?
While the cause of the fish kill in Lake Ariel has yet to be determined, fish kills are not an uncommon event during the summer months.
Northeast Pennsylvania recently experienced a week-long heat wave with high consistently around or above 90 degrees.
According to the United States Geological Survey (USGS), "many, but not all, fish kills in the summer result from low concentrations of dissolved oxygen," in the water.
Fish get their dissolved oxygen from oxygen gas dissolved in the water, which is why home aquariums have an aeration device.
During the summer months, warm water "holds less dissolved oxygen" than cold water, which can cause fish to have a difficult time getting enough oxygen. While other organisms, such as plant life like algae, produce oxygen during the day, the night time production of oxygen ceases.
This stop in oxygen production can cause the dissolved oxygen concentration can drop low enough for a fish die-off too occur. It can be caused by completely natural events or by human activity that disrupts the ecosystem.
Fish kills can also occur as a result "of toxic compounds released into a body of water." For this to occur, the compound "must be fairly highly concentrated."