Foto: Konrad Kulawik

Grass snake (Natrix Natrix)

The grass snake is easily recognizable by two yellow spots on the back of the head. Its coloration is variable: brown, gray, olive, and even black. The body of approx. 100 cm in length is covered with small, rough scales. During the year the grass snake sheds its old moult several times. It feeds mainly on frogs which it catches in the wide-open mouth and swallows whole. It swims and dives perfectly, thus it is sometimes called a water snake. It is encountered on river banks, lakes or ponds with dense vegetation. Sometimes it occurs in home gardens. We do not need to be afraid of it because it is completely harmless. When threatened it shows its “acting skills”. It can feign an attack by hissing shrilly and raising its head like a cobra. Alternatively it tries to scare the enemy away by suddenly vomiting food or secreting a foul-smelling substance from its anal glands. When all these methods fail it pretends to be dead. Its eggs are soft and spherical. The female lays them at damp spots, rich in remains of plants (compost, animal manure, piles of rotting leaves). It uses the rotting process of plants in which heat is generated to keep the eggs warm. Grass snakes are threatened by pesticides, especially herbicides used in their habitat, as well as by the pollution of water bodies and forests.