On the status of the fire-bellied toad, Bombina bombina, in Lobau (Vienna, Donau-Auen National Park)

We investigated the population ecology of fire-bellied toads, Bombina bombina, at three study areas in Lobau, a part of the National Park Donau-Auen in Vienna, Austria. In 2008, we estimated population sizes using call surveys and recapture analysis of individually registered toads, with best estimates ranging from 115 to 650 individuals per study area. High proportions of subadult toads indicated recent successful reproduction at two of the three study sites. Yearlings gained on average 1.1 mm in snout-vent length and 0.3 g in body mass every ten days from April to August. Assessment of conservation status is hampered by the absence of data on migration and dispersal, which could allow delimitation of conservation units. We discuss implications of our results for surveillance and habitat management, stressing the importance of temporary water bodies for reproduction and recommending to focus surveys on metamorphic success.