Lizards

Four lizard species can be found in The Netherlands. The photograph below shows a Common lizard (Zootoca vivipara), which is the prevailing species. Common lizards give birth to live young (hence the name vivipara), which is an advantage for reptiles that live under relatively cold conditions. Eggs hatching inside the mother renders the developing embryo's less dependent on the warmth of the sun, and makes them less dependent on the temperature in one particular place. Pregnant females are often seen basking in the sun. Important area's for lizards occurring in The Netherlands are moors rich in structural variation (with lots of heather), often alternating with bushes and forests as well as dunes along the coastline. Wall lizards (Podarcis muralis) are found in one place only in the South (Limburg).

The Slow-worm

The Slow-worm (Anguis fragilis) is a legless lizard. Internal and external features still are prove of these animals being typical lizards. Shoulder- and pelvic structures are for example still present.

The Sand lizard

This lizard (Lacerta agilis) is the most robust lizard species of The Netherlands. The species is usually found on sandy soil. In the dune area's along the coastline, as well as in the central, Eastern and Southern parts this lizard is found. Male Sand lizards develop a green coloration during the mating season (see photograph on the left). Females keep the usual brown and browngray colours throughout the year. The individual patterns of stripes and spots are dark brown to black. In this way discrimination between different individuals is possible.

Snakes in The Netherlands

Three species of snakes are present, all of them being quite shy and inconspicuous in their behavior. Usually these snakes disappear rapidly when spotted. The different species often hibernate in particular places together with other individuals. A number of herp-species may even hibernate together. In spring and fall many reptiles may therefore be found near such hibernating-places (known as 'hibernacula'). One species is seen mainly in swampy area's. This is the aquatic Ringed snake or Grass snake (Natrix natrix subspecies helvetica). This is the only snake-species in The Netherlands that lays eggs. When disturbed basking snakes disappear immediately. Occasionally the disturbed animals may play dead.

The Adder

The Common viper or Adder (Vipera berus) is the only poisonous snake in The Netherlands. The center of its distribution is limited to a number of nature reserves in the eastern parts of the country, the middle and in the South. In some nature reserves many victims of bikers are registered; the animals bask on the paths and are unable to move fast enough when bikers approach.

The Adder is a predator at the top of the food chain. Among other things mice are an important prey. The animals display an array of different colors. Males usually are creamy colored to a brownish beige. Females (photograph on the left) may reach a larger size, and are most of the time brown. Both sexes have the typical zigzag stripe pattern along their body. The Adder eye has a clearly distinguishable slit-shaped pupil that is positioned vertically.

The Smooth snake

This is the rarest species of snake in The Netherlands, sometimes found together with the Adder. Smooth snakes lead a somewhat hidden life, however pregnant females in particular, can be seen in the same spots regularl, since they do not seem to go very far from their hiding places. The female Smooth snake (Coronella austriaca) is most of the time dark colored, males are usually lighter with brownish patterns; both sexes show a pattern of spots and stripes.

Smooth snakes give birth to live young, like the Adder. Mortality however in juveniles is high during the first years. In August and September young Smooth snakes are usually born, and can be seen most of the time quite close to where their mother was seen basking before.