Deutsche Welle: Jellyfish are taking over Europe’s favorite swimming spots in increasing numbers. Scientists blame climate change and overfishing for the proliferation of the stinging nuisance. While Mediterranean resort areas will be hardest hit by the jellyfish plague this summer, there will also be high concentrations in the Baltic and North Seas, according to scientists. They warn that the dramatic increase in jellyfish is a sign that ocean ecosystems are out of whack. “Jellyfish are …