Just how important is supplementary food to the success of the Red Kite reintroduction?

Arron Watson

Red kites are predominantly opportunists and scavengers but those two activities can mean having a totally different diet depending on where they live. A red kite which lives in the isolated highlands of Scotland may only be able to scavenger on dead rabbits, pheasants and opportunities of stealing the offspring of birds, such as magpies and crows. Whereas, a red kite that lives in the Chilterns (Berkshire) will have access to urban areas of High Wycombe and Reading, which may offer a different menu than what would be on offer in areas where there is less human waste.

Human waste allows a scavenger and opportunist to develop skills that could change the future of its survival and this has already been seen within the European Red Fox. Red foxes have adapted to live amongst humans, living in their gardens where they have been known to raise their young. This adaption has allowed them to move away from relying on wild food (like rabbits and small mammals) and be able to understand where and when there may be food within urban areas instead.

This opportunity of regular food in bins for foxes has an even more unusual twist to how red kites access a large majority of human food waste. The opportunity of being fed on people’s drives and gardens on a regular basis has meant that other red kites have noticed this opportunity and adapted to this way of life. Now, in some areas of the country like Reading, up to 30 red kites can be seen at once circling regular feeding sites.

Could the future of the red kite see the same adaption of red foxes, nesting more in urban areas and not relying on wild food, and what would this mean in terms of the survival as a species? If looking at the survival of the red fox and choices of change of lifestyle, there are mixed opinions of the pros and cons to this. Reports of people leaving food in their garden for foxes’ because people enjoy seeing them. While other reports have suggested that they are a menace, one report described a fox climbing in a person’s window and attacking a young child because of their close proximity within urban areas.

The boundaries of opportunity when feeding wildlife is one of the biggest issues that could change a species future. How does the animal know when, where, and what not to do when being fed by a person? Animals know how to survive, which means they know how to find food, reproduce and, in times of stress, will resort to using any skills they have to ensure a future for themselves and their offspring. Considering the increasing population of red kites feeding in urban areas and becoming more reliant on people feeding them – what happens when specific areas stop feeding? Or the amount of food that has been persistent for a period of time reduces?

The figure below expresses what could happen with two different scenarios of food availability while red kites survive and reproduce. Scenario a) shows as the amount of wild food availability increases the percentage of food available for red kite populations increases. As some of their predominant food source includes carrion of small mammals and invertebrates, this means the summer period dictates the increase in abundance in excess from reproduction of these species (the line goes up). Whereas in the winter months when specific species hibernate and the cold weather dictates the abundance of many species which would be eaten is based on anything available (the line goes down).

Scenario b) shows the dramatic increase of food available in people’s gardens and other areas where food may become available in urban areas (the line goes up and down randomly). In this scenario because there is no fixed routine of where and when food may be available as the food available increases it can decrease very rapidly because of the random amount and time of food. When matched against the breeding season of the red kites it shows an unstable increase and decrease in food, however this scenario is hypothetical to prove the point of how a specific animal could be impacted by relying on food from an unstable source. If an animal decides to have offspring it needs insurance of regular food, so by matching against other food species life cycles as shown in a) the survival of its offspring is insured.

Does this mean that it is bad to feed red kites? It is catch 22 in a way. The red kite populations have increased in urban areas because of this activity but at the same time more red kites will have to eat in a specific area, and – if they originally survived and had offspring because of supplementary feeding – this in theory should have to persist to support all red kites in that area. Or, the other way to look at it would be that they may increase in population sizes because of urban feeding and disperse further in to the countryside and survive in the wild like they did a century ago.

This episode was meant to help people understand how humans can impact wild species without intentionally meaning to change the future of a species, there is no easy answer to if feeding red kites is okay but being more aware of how they could be impacted is very important to the general public.