Common frog (Rana temporaria) is the second species in the group of brown frogs (subgenus Rana), found in the Notranjska Regional Park area. The common frog is medium-sized, somewhat chunkier frog with a broad, rounded head and a short, blunt snout. The trunk of an adult animal measures from 4 to 11 cm, males are smaller than their better halves. Its hind legs are relatively short, which is especially noticeable in comparison with the long-legged newt. The tympanum, a round depression behind the eye, is smaller than the eye in the common frog. It is also characteristic of it a marbled pattern of darker blotches and specks on a milky or dirty white, sometimes yellowish or even orange belly. On the back and hips it is usually reddish to gray-brown and often sprinkled with darker spots. Like other brown frogs, the common frog also has a distinctly dark brown mask drawn over the eyes.
In Slovenia the common frog is widespread. It prefers cooler, mountainous areas, so here we find it up to 1700 m above sea level, and it avoids Slovenian Istria and Primorje. Its habitat are shady, moist forests and forest edges, but it also does well in dense vegetation on swampy meadows and marshes. In dry and warm days it hides under leaves, rotten wood or stones, among the roots of trees and shrubs or in dense vegetation; at dusk and on moist days it goes out to hunt for slugs, spiders, insects and other invertebrates.
To breeding sites, which usually consist of shallow standing or slowly flowing bodies of water in sunny places, the common frog migrates in large numbers during the first warm period after winter. At the breeding sites they stay from February to April. During this time, males with the stretched-out rroar-rroar-rroar-rroar-rroar croak to attract females. The spawn masses, which in diameter measure from 10 to 30 cm, are often laid in groups, so that individual spawn masses cannot be distinguished from one another.
Common frogs overwinter on land individually; there are also known group hibernation sites at the bottom of water bodies, where as many as several thousand can gather! One such hibernation site is also located at the edge of Lake Cerknica.
The common frog is protected in Slovenia and, as a vulnerable (V) species, is also listed on the Red List!
