Your lunch is in the freezer

Thomas D Mangelsen travels the world for seven months a year photographing wildlife. Every November, he returns to Hudson Bay, in Canada, to photograph polar bears. 'They congregate along the shore of Hudson Bay to wait for the bay to freeze. Once it does, they move out onto the ice to hunt seals, their primary food. Arctic foxes are often with the bears, scavenging the leftovers.' The above photograph, taken on his last visit, won him the top prize in the 1994 British Gas Wildlife Photographer of the Year competition.

This attracted 12,100 entries from 50 countries, and the best of them - over 100 photographs - are on show at the Natural History Museum from today until 26 February. Among the runners-up, in the 'Urban and Garden Wildlife' category, is another photograph (right) by Mangelsen, who lives in Jackson Hole, Wyoming. It shows a bald eagle eating prey while perched on a sign in the shape of a salmon, which advertises a fish market near Kachemak Bay in Alaska.

The exhibition is open 10am-5.50pm Monday-Saturday, 11am-5.50pm on Sunday.

Admission is pounds 5 (adults), pounds 2.50 children (aged 5-17) and concessions, pounds 13.50 family ticket (two adults and four children)