Pesticides could be to blame for a glut of deformed birds handed in at an Oxfordshire sanctuary.

Now the owner is building up a dossier on similar findings and trying to come up with an answer. Penny Little of Great Haseley runs the Little Foxes sanctuary. Over the last few weeks she has had deformed creatures brought to her, including a sparrow with only frills for wings, a baby wood pigeon less than half the size it should have been, and two collared dove chicks only a fraction of their normal size, one of which died yesterday.

Mrs Little said: "This influx of deformed birds has me worried. I don't have any real statistics, but I am very concerned. These are all seed-eaters, so I feel they could be the victims of some sort of pesticide pollution. Garden as well as farm pesticides could be responsible. I am well used to feeding tiny birds and seeing them survive, but I've never seen anything quite like this. I just desperately hope it is not a trend."

She now wants other sanctuaries and animal hospitals to log any cases of malformed creatures to see any pattern. The Royal Society for the Protection of Birds said pollution by heavy metals or pesticides could lead to severe abnormalities.