Smooth Snake

• Males live markedly longer than females — up to 25 years against 15.
• It catches lizards and other vertebrates by constriction.
• It is often mistaken for the adder despite being entirely harmless.
• It is not venomous: it kills by constriction, something uncommon among European snakes. It holds its prey with its teeth and coils its body around it.
• It eats mainly small lizards and other reptiles, including the young of other snakes.
• It is constantly confused with the viper, and that confusion costs many individuals their lives. It can be told apart by its round pupil — the viper's is vertical — and by its smooth rather than keeled dorsal scales.
• It is ovoviviparous: the eggs develop inside the female and the young are born fully formed, wrapped in a membrane they break through straight away.
• It is among the hardest European snakes to see despite being widely distributed, and in the United Kingdom it is one of the most strictly protected reptile species.

Skeleton type

Vertebrate - internal bony skeleton (reptile)

Habitat and environment

Heath, sunny rocky slopes and woodland edges across much of Europe as far as the Caucasus

Birth weight

Exact weight at birth not found as a precise figure

Size at birth

Precocial, born live and fully formed

Sexual maturity

4 years

Gestation / incubation

Internal gestation; the young born live (ovoviviparity) towards the end of summer

Litter / clutch size

4 to 15 young per litter

Life expectancy in captivity

Documented record of up to 15-20 years in captivity

Sources consulted: British Herpetological Society (longevity study); A-Z Animals; ResearchGate (reproduction probabilities study); Animalia.bio; Britannica; PMC (age-dependent shelter use study)