Every visitor should experience night-time on Skokholm. Over half the world's population of manx shearwaters nest here and on a neighbouring island, so you're guaranteed a close encounter. Dave Millboro the warden shows Mike Dilger the best spot - at 1.15 in the morning. An image intensifier camera is needed to see some of the action. A manx shearwater hits Dave in the back of the head. Storm petrels' burrows are in the back of the walls. They are tiny birds, about the size of a swallow. A torch with a red filter lets you see the birds without drawing too much attention to them. They are really clumsy on land, since their legs are at the back of the body, but are brilliant swimmers and fliers.