Saved by their stripes: Africa's vanishing herds

Jessica Aldred
guardian.co.uk, Sunday November 30 2008 00.01 GMT

As the rain begins to fall on Tanzania's Tarangire National Park, thousands of zebra, wildebeest and giraffe will begin one of the world's greatest migrations. But many of the herds trampling across the grass at the foot of the Rift Valley highlands are falling in number - and scientists do not know why.

To find out, they are using a new 'photo-fit' system that can recognise individual animals by their unique skin patterns, which are as distinct as a human fingerprint.