DISSEMINATION
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DISSEMINATION |
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| Kingdom | Animalia | 
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| Phylum | Chordata | |
| Class | Reptilia | |
| Order | Squamata | |
| Family | Colubridae | |
| Genus | Natrix | |
| Species | natrix | |
| Classification | Linnaeus, 1758 | |
| Common name | grass snake | |
| Size | 90 - 150 centimeters |
| Geographic Range | it is found almost everywhere in Europe, with the exception of Ireland, the Baleraric Islands, Crete, Malta. It is found in north-western Africa and eastern Asia. |
| Physical Characteristics | the colour of the body is usually olive-green, brown, grey, whereas the pattern changes from region to region: in northern Italy the individuals have dark spots and dark stripes along their flanks. It has a characteristic orange, yellow or white collar around the neck. It has a rounded head; in the adults the back part of the head is larger; it has a rounded pupil. |
| Behaviour | it hibernates from October to March in ground holes or under leaves. It is mainly diurnal. It is harmless for humans, but if it is disturbed it can give out a shrill whistle and try to hit the stranger with its closed mouth. It seldom bites. When it gets caught its anal gland sends forth a disgusting smell. It sometimes pretends to be dead in order to distract its enemy: it lies on its back with its mouth half open and its tongue hanging down. It is a good swimmer, it may hold its breath for even thirty minutes. It plunges in the water to hunt its prey (fishes, frogs, amphibians). The grass snake locates its prey feeling vibrations on the ground, then catches it with its mouth and swallows it while the prey is still alive. The grass snake has no mandible joint and that allows it to swallow prey even bigger than its head. Once the grass snake has swallowed its prey, it can digest it thanks to powerful gastric juices. |
| Habitat | it prefers environments associated to water where it can feed on amphibians and fishes. |
| Food habits | molluscs, insects, tadpoles, frogs, newts, salamanders, fish, toads, small rodents, lizards, nestlings. |
| Reproduction | it may lay from ten to forty eggs in June-July in a nest built with grass and humus: the heat developed by decomposition helps eggs incubation. Eggs hatch around September. More than one female can often share the same nest. |
| Status in the lagoon | it is found mainly in the areas associated to soft or little brackish water, most of all in the areas closer to mainland or in the fishfarms ( Dogà, Grassabò, Fosse, Cavallino, Lio Maggiore, Liona, Olivara, Paleazza, Perini, Serraglia, Averto, Cornio Alto, Figheri, Pierimpié, Ghebo Storto, Morosina, Millecampi), Bosco Nordio, Cassa di Colmata "A" and "D/E" (“A” e “D/ E” reclaimed areas), Teneri lakes and nearby saltmarshes. |
| Sources | |
| References | Batraciens et Reptiles du Monde Web Museo dell'Ittiofauna Europea Le Aree Umide della Toscana Settentrionale Guida alla natura nella Laguna di Venezia - di Giampaolo Rallo - Franco Muzzio editore |
| Web References | http://perso.wanadoo.fr/batraciens/ http://www.ittiofauna.org http://www.zoneumidetoscane.it/ http://reteambiente.it |
| Source of the photo | http://www.lincstrust.co.uk/species/amphibia/grass-snake.html |
| Source of the video | http://www.offwell.free-online.co.uk/ |
Natrix
natrix
