Fish kills are a recurring phenomenon in lakes suffering from oxygen depletion.
Fish kills are a recurring phenomenon in lakes suffering from oxygen depletion. Often the kills are triggered by factors like an algae bloom, but now a new study reports on a new, climate-related cause of fish kills.
A grave example is reported from a lake in Denmark. In 2018, Denmark was hit by extreme summer drought and temperatures in May, June and July were 3 degrees higher than the average for the previous 30 years. At the same time, an average of only 27 mm of rain fell compared to normally 56 mm.
The lake, called Lake Filsø, received no rainfall until a thunderstorm with heavy rain blew across the lake on July 28, delivering 22 mm in only a few hours.
Resets an entire ecosystem
‘Huge amounts of water flowed from the catchment into the lake and brought with it huge amounts of organic material. This cocktail led to massive fish kills in the lake. Events like this are dramatic and can completely reset an entire ecosystem,’ explains biologist and Associate Professor Theis Kragh from the University of Southern Denmark.
Read more at University Of Southern Denmark
Photo Credit: Theis Kragh