Going back to our subspecies of Natrix Natrix Natrix, she finds herself in Germany (East of the Rhine), Eastern Switzerland, Central Europe, Eastern Europe, Scandinavia, Finland and the Crimea. The populations present in Belgium were introduced.
The Natrix Natrix Natrix has a uniform color can vary from gray to brown, it has very few drawings and when present, they are limited to a few scattered yellow dots. It is quite svelte and slender, males are on average 70cm while some females may exceed 120cm.
It has a yellow collar around the neck, which whitened with age finally often entirely white.
Juveniles are carbon copies of adults but with slightly lighter colors and a well-yellow collar.
You should know that the Natrix Natrix, and therefore the Natrix Natrix Natrix, spend more time on land than Natrix maura and tesselatta.
Reproduction is annual and begins after a winter rest (usually from October to March, sometimes a little less in warmer areas) when temperatures rise above 10 ° C. It is in spring that have places couplings and clutches (on average about twenty eggs but spectacular clutches of 70 eggs have been observed) unfold from late June to early August. Like some other fish-eating species, such as Thamnophis some prenuptial gatherings can consist of groups of a few dozen individuals.
Young individus are the prey of many predators including the Montpellier snake (Malpolon monspessulanus) and the smooth snake (Coronella austriaca).
The Natrix Natrix Natrix feeds mainly on small vertebrates, fish and amphibians. Observations with cases of predation on the spotted salamander have been observed. Adult, it can also feed on small mammals, but this is quite rare. It usually hunt actively and it is rarely seen on the lookout.
Drought of water bodies and the decline in amphibian populations in parts of France (Loire-Atlantique for example) directly affects populations of Natrix Natrix Natrix. artificial spawning sites are in place for several years in France, Belgium and Switzerland.