Country diary: adders find their place in the Scottish sun

Aigas, Highlands: Emerging from hibernation, these snakes seek out a warming rock to get energised for the hunt ahead

Warmth is what it takes, that's all. Every spring that first burst of sun in clear skies brings our adders back to life. In common with most other reptiles the world over, Vipera berus has to warm up. They are cold-blooded and have been hibernating underground for more than six months. Their metabolism will have all but closed down. They need to fire it up again.

Related: Why we must make the adder count | John Baker