Mayfly swarming on the Danube attracts visitors in Hungary

In early August the spectacular mayfly (dunavirág) swarming began along the Danube, with large mating clouds observed near Budapest bridges and at Dunakeszi. The protected insects, only a few centimeters long, rise briefly at dusk to release eggs, and special blue light barriers have been installed on several bridges to keep them above the water and aid their reproduction.

Photographer Ujvári Zsolt captured the phenomenon, and his images are featured in a festival in Szentendre. The event includes a photo exhibition, land‑art workshops, an evening rain‑dance, and a rescue operation organized by the Szigetmonostori Water Sports Association with WWF Hungary support. Ecologist Dr. Kriska György and WWF experts give talks on the species, its vulnerability to light pollution, and conservation measures.

The festival aims to raise public awareness of the Danube’s ecological value and to promote responsible observation of the mayflies, which are valued at 10,000 forints each under Hungarian protection law.