This is from an article written by Peter Edwards of the Southern England Kite Group.

Red Kites Overhead

We now have a thriving population in the Chilterns that is rapidly colonising the Home Counties without our help. All they need is our continuing protection from persecution and adequate food. Concerns were raised that feeding kites might slow down colonisation outside of the Chiltern area and that feeding inappropriate food may affect the health of birds, especially chicks. As a result there was a meeting of experts from Natural England, RSPB, London Zoological Society, Welsh Kite Trust, South of England Kite Group and the Chiltern Conservation Board and it was agreed that there was no evidence for this. In fact it was agreed that feeding the kites was clearly beneficial. As a precaution feeding guidelines were revised listing inappropriate foods like cooked meat that may be deficient in calcium that is needed for growing bones. Uncooked meat containing skin and bone is best. During 2007 there was a reduction in feeding by the public in response to publicity about these concerns. This coincided with the poorest year on record for red kites breeding in the Chilterns. Since the beginning of the release project Chiltern birds were the most productive, fledging on average 2 chicks/nest, more chicks fledging per nest each year than anywhere else in the country. Since 2007 the Chilterns was almost the lowest fledging on average 1.6 chicks/nest. This may represent the combination of the high density of kites breeding in Chilterns and competition for food. We have also observed that brood sizes remain higher on the edge of their range where densities are lower, but growing and the range extending. Feeding kites is likely to maintain their populations at higher densities and increase their rate of spread, but is probably no longer necessary for the successful establishment of the population in the UK. As a result the Southern England Red Kite Group neither encourages nor discourages the feeding of kites in the Chilterns. We would like to make it clear that responsible feeding means taking into consideration how your neighbours feel. It should also be remembered that these magnificent birds are opportunists and will quickly recognise new sources of food, especially in the summer when they have chicks to feed. So it is no great surprise that food made available once or twice on a school playing field, for instance, may be an invitation to come back for more and sometimes not always with the owner’s consent.