Danube Virtual Museum

Amphibians

Marsh Frog (Pelophylax ridibundus - Rana ridibunda)

The photograph shows a juvenile specimen of a large marsh frog, one of Europe's largest frogs. Females usually reach a length up to 14 cm while males up to 12 cm. Their dorsal side of the body is olive-brown, grey-brown or dark green with several large dark brown spots irregularly rounded. The belly side is whitish, grey or black.

Males have blackish sound bubbles and their croaking is heard as "bre-ke-ke-ke. This species inhabits ponds, marshes, fishponds, streams and rivers. In areas with other types of marsh frogs, it usually chooses to be closer to bigger aquatic habitats - rivers and lakes. It mainly inhabits plains or low lands, although it can be found at an altitude of over 2,000 metres. The diet of the marsh frog consists of various invertebrates and vertebrates of small size such as fish, waterfowls, and amphibians. Examples of cannibalism have been recorded. The species is widespread in Serbia.

Agile Frog (Rana dalmatina)

The Agile frog belongs to the group of Brown frogs. The maximum body length of this frog is 9 cm. One of the main characteristics of these frogs is very well developed and elongated hind legs.

Males do not have sound bubbles but they produce quiet, quick sounds like "rog, rog, rog". The Agile frog is bound to the water only in the breeding season. Females remain in water until they lay eggs, unlike the males, who stay in the water for several weeks and can mate several times during that period.

Terrestrial invertebrates dominate in the diet of the Agile frog. It mainly searches for food at night, but also during the day when humidity is very high. It can be seen in the Danube areas, in the woods and shrubs around the river.

Litеrаture

Paunović, A., Bjelić-Čabrilo, O., Šimić, S. (2010): The Diet of Water Frogs (Pleohylax esculentus “complex”) from the Petrovaradinski rit Marsh (Serbia). Arch. Biol. Sci., Belgrade, 62 (3), 797-804.

(Text: Natural History Museum in Belgrade)