Foto: Łukasz Siudziński

Moor frog (Rana arvalis)

The moor frog belongs to brown frogs whose back and sides are shades of brown with dark spots. On the hind legs, joint by a membrane, there are transverse stripes. The skin is thin, moist and smooth. This tiny amphibian grows up to 8 cm. It lives in forests, wet meadows and bogs. The life cycle comprises three stages: the hibernation, mating and the active period. The hibernation lasts for 6 months, during this period the frog hides under piles of branches, leaves, or in a hole. The mating season begins in April. Then the males changes its coloration into the blue hue so characteristic of this species. In search of females they swim actively on the body of water that looks like a deep blue meadow. The female lays spawn in the form of spherical packets. The fertilization is external. From eggs develop brown tadpoles that within three months undergo transformation into the adult form. The moor frog is extremely timid. For breeding it chooses quiet water bodies located in forests or separated from the shore by a wide belt of rushes. Rushes create a thermal and protective barrier against predators. After the end of the mating period the active period begins. The moor frog leads a largely terrestrial life, it hunts for invertebrates or basks in the sun.