Catnav to track murderous pets

Researchers plan to use GPS devices to follow domestic cats. Photograph: Jane Burton/Guardian

They may be favoured household pets, but a study by the University of Reading found that Britain's domestic cats are responsible for the deaths of millions of small wild animals each year.

Researchers plan to use GPS tracking devices to determine the area over which each cat roams, to find out how many birds and small creatures it kills and thus what wildlife is at risk in its local area.

The idea of a catna