- Potential oxygen deficiency leading to mass fish fatalities in the Arend Sea.
Seems like we're talking about a fish crisis in Arendsee, Altmarkkreis Salzwedel. Experts believe that the high water temperatures and lack of oxygen could be behind this recent fish mortality. Upon examination of the deceased fish, authorities discovered an intense infestation of parasites and a bacterial infection. Fortunately, no signs of notifiable animal diseases were found, reducing the initial risk to human health.
The rampant parasite infestation might have been aided by the high water temperatures and the stress or compromised immunity in the affected animals. Information from the Leibniz Institute for Freshwater Ecology's monitoring station revealed that a hypoxic zone had already emerged in June, situated between 10 and 12 meters below the surface.
Fish deaths in water bodies like ponds and lakes in Saxony-Anhalt are not uncommon. Arendsee, with its over 50-meter depth, is Saxony-Anhalt's deepest natural lake and one of the largest deep lakes in Northern Germany. The district stated that a summer standstill typically occurs during the summer, resulting in the formation of three layers with varying temperatures and oxygen levels.
The district anticipates the fish crisis to come to an end in the fall when these different water layers mix again. The deceased fish are being consistently gathered and disposed of. The majority of the deceased fish are young pike, a preferred food source in the Arendsee region.
In the past five years, Saxony-Anhalt has witnessed over 70 instances of fish deaths. Low water levels in ponds and lakes, as well as oxygen deficiency, have often been the culprits behind these events.
The high water temperatures and oxygen deficiency could exacerbate the fish's vulnerability to parasites, contributing to the lack of oxygen-related fish mortality. The hypoxic zone, detected in June, might have affected the oxygen levels needed for the fish to survive, leading to their demise.
