After the case of parasites – “sweltering” heat: are other lakes threatened with closure?

Long awaited on hot days like this: jumping into the cool water. Only in the natural swimming lake Wechselland in Pinggau is the “Köpfler” currently not possible – because there is a swimming ban due to the risk of rash! Due to the high water temperature, the bone larvae responsible, the so-called cercariae, multiplied very quickly (we reported).

Swimming lakes already offer ideal conditions for parasites
“Worm eggs, which infect waterfowl, are excreted, and in turn infect water snails. From about 24 degrees in the lake, the cercaria are released en masse,” explains hygienist Franz Reinthaler. Temperatures that most Styrian lakes have already exceeded.

So is it likely that there will be more sea defenses in the near future? “If larvae are already inside, the heat makes it more likely,” Reinthaler says. Many lakes are already affected, as are most birds: “In recent decades, this has been increasing.” Warm summers also make it easier for the larvae to hibernate.

More and more effort for operators of swimming ponds
That is why the Bad Weihermühle, which is currently 26 degrees, is left outside every year and attempts are made to keep birds away, for example with motion detectors. “We also put new gravel and whitewash on the lake,” says operator Elias Theiner, “the snails don’t like that.” Germs, also confirmed by the dental hygienist. Constantly checked and samples taken.

Lakes also “tilt” easier
Heat also causes lakes to “overturn”: warm water has less oxygen, plants die – a bad smell. Heavy rain helps little here: dry soil absorbs little water, nutrients are washed away in water bodies, causing more algae to grow, which in turn removes oxygen.