European Adder (Vipera berus)
Usually by mid April, male V. berus have shed their dull winter skins and are eager to mate. During warm humid days there is often much frenzied behaviour, with the males looking for females and occasionally duelling with other suitors. During this time the males writhe around each other often covering the ground at great speed. It is an impressive site if you are fortunate to witness it and one that is unlikely to be forgotten. The two males pictures above were photographed in West Sussex on the 17th April.