TUBE passengers are being urged to help London's bird population by entering a photographic contest.

Entrants are asked to snap pictures of wild birds within a five-minute walk of a London Underground station for a chance to win a prize.

In the past five years, 42 bird species have been spotted on London Underground property, including Walthamstow Central, Blackhorse Road, Leytonstone and Leyton stations.

The competition is being launched by London Underground and charity the Royal Society for the Protection of Birds (RSPB).

Tim Webb, from RSPB London, said: "We all rush around in our daily lives, rarely taking time to pause and admire what's going on in the wider world.

"Here's the ideal excuse to lift your eyes and discover the wildlife that lives alongside us."

The competition is open from today (Thursday) until Sunday, May 31 and the pictures will be judged on relevance and originality.

The judging panel includes birdwatcher David Lindo and the winners will be announced in July.

Prizes include an annual pass to RSPB reserves and a family pass to the London Transport Museum in Covent Garden, as well as bird feeders and books.

Entrants can upload their photos at www.flickr.com/groups/LU-RSPB_MindtheBird stating where the picture was taken.

There are separate categories for adults (18 and over) and children (under 18).