Clouds of mating mayflies.
As the day came to an end so did the life of these aquatic insects. Once changed into their final, winged forms, they emerge from the water and have only a very short window to mate before they perish. Doing it all at the same time greatly improves their chances against predation, and provides an unforgettable show to the observer.
The wilderness of the Danube Delta is abut much more than just birds.
Andy Raynor Dover NH