Commuting Kites - conservation success or urban pest?

Almost half of UK households regularly feed wild birds, but would you invite a raptor to dine in your garden?

In Elizabethan times, the distinctive silhouette of the majestic Red Kite (Milvus milvus) was a common sight across the UK. However, following centuries of persecution by gamekeepers and farmers, Red Kites were extirpated from England and Scotland by the late nineteenth century, leaving just a few surviving pairs in Wales by the 1930s^4,5.

Now, thanks to a hugely successful reintroduction programme Red Kite populations have made an incredible recovery. Using birds from Swedish populations, reintroduction started in the Chiltern Hills in 1989. Over the past 25 years Red Kite numbers have grown to an estimated 2,700 pairs nationwide².

As part of their impressive comeback, Red Kites have become regular visitors to the urban conurbation of Reading in Berkshire, around 20km from the original release site³. According to a recently published study from the University of Reading, as many as 300 Red Kites have been seen visiting the town each day. It was originally assumed that the Kites were attracted by waste food and roadkill³, but surveys predicted that the quantity of food available from these sources would only support 13-29 Kites per day³. The real attraction for such a remarkable number of raptors lies with a large proportion of the residents...

The study found that almost one in 20 households in the area regularly leave out food for Red Kites. This amounts to more than 4,300 households - creating a major incentive for Kites to ‘commute' into town from the surrounding countryside for their meals^3,4. Given that there are only three confirmed breeding sites and no substantial roost sites in Reading or its direct surrounding area, they must be travelling a fair distance to do so. In total these households were estimated to provide enough food for up to 320 Kites (a considerable proportion of the 140-440 that are estimated to visit the town each day)³.

Clearly such supplementary feeding is playing a significant role in the Red Kite's recovery, but not all residents are quite so happy to have them around. As with any animal in an urban environment, particularly predatory ones, conflict is not uncommon. Concerns range from the minor to the arguably sensationalist. Some, quite fairly, lament the soiling of their cars and washing with the birds' droppings, whereas others worry that raw meat dropped by Kites will attract rats. On a more amusing note, one particularly opportunistic Kite was reported to have swiped some sausages from a barbeque. The biggest fears, however, are that Kites will take small pets from gardens, with one woman claiming a Kite "stalked" her and her small Pomeranian dog, even attempting to grab the tiny pooch whilst they were out walking in the park. A member of the RSPB (Royal Society for the Protection of Birds) spoke out against such claims, arguing that there have been no reported cases of a Kite taking pets such as rabbits or guinea pigs, let alone small dogs, and that these animals would be too large for a Kite to carry off anyway¹. Nonetheless, there has been a backlash against feeding and encouraging these birds to visit gardens.

The complaints don't just come from residents either; conservationists are also expressing concerns about the consequences of this supplementary feeding. The original purpose of reintroducing the birds to the Chilterns was to create a secure environment where numbers could accumulate before spreading to other areas of the UK. Garden feeding, however, could result in an unsustainably high population which is reliant on humans for food, preventing them from dispersing elsewhere. Causing them to cluster in urban areas could also lead to sensationalist stories which will promote a negative view of Red Kites, harming their reintroduction elsewhere. The study authors suggest that long term supplementary feeding could have both ecological and evolutionary influences, ranging from "the potential release of poor-quality individuals from selective pressures [...] to the potential for Red Kites to become overabundant ‘native invaders'" with knock-on effects on other species³.

Concerns have also been raised over the quality of the food the Red Kites are being given. In the wild their diet would contain bones and skin, both of which provide vital nutrients, in particular calcium - a deficit of which has been linked to growth and bone disorders in some juvenile Kites. Cooked foods and processed meats also have lower nutritional value than natural food and contain potentially harmful additives such as increased salt³. An amateur website (www.redkites.net) gives some good advice on feeding, such as avoiding cooked processed foods, only giving small amounts, infrequently, feeding late in the afternoon to encourage the Kites to forage for themselves in the mornings, and avoiding wild carcasses that may have been poisoned (i.e show no signs of injury).

One of the study authors, Professor Mark Fellowes has also suggested that feeding may have helped increased the Red Kites' chances of survival during cold or wet winter periods, which make finding food in the wild difficult, so supplementary feeding in heavy snow for example, could give the birds a helping hand⁵. On a wider scale, with the Red Kite showing declines over much of its core European range, the renewed UK population could even act as a lifeboat for the species' survival on the continent.

Despite these concerns, and a number of disgruntled neighbours, the fact that so many people have taken an interest and found joy in seeing these incredible birds is at least a positive step for conservation and human-predator relations. Arcing across the sky with their distinguishing forked tail, handsome copper plumage and a wingspan of almost 6ft, they really are a sight to behold. It's a strange, but not unprecedented turn of events, for us to fight so hard to reintroduce a species we hunted almost to extinction locally. Hopefully the pattern will not repeat itself, and cases like this show that we are willing to learn to coexist with the few wild predators we have left on our small island.

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