How the red kite came back from the brink
Well let’s look skyward for one very visible example of reintroduction successfully in action, which is the tale of the red kite. Harry Lewis spoke to Will Dixon, who did his PhD as part of the team involved in returning red kites to British skies in the 1990s, and he told him how to spot one…
Will - It's a very characteristic bird. It's one of the largest birds you'll find in the UK. It's got a wingspan of over a meter and it's got a very distinctive forked tail. The red kites fly by catching the wind and so they're constantly twisting and adjusting their wings and their tail, which keeps them airborne with very little effort, which makes them very efficient at flying large distances, looking for their food.
Harry - And obviously we're talking about reintroductions and this one's quite special, isn't it?
Will - It is. It's one of the first successful reintroductions in the UK and, at the time, it was considered quite risky. I mean, these were birds that were globally endangered. The project involved bringing birds from an area in the wild where they were thriving, but there were still concerns about that conservation and releasing them to an area where they hadn't lived for over a hundred years. And the worry was, has the environment changed too much? Are the reasons they went extinct still there? Is it a waste of resources? And would we be better off focusing attention on conserving the birds where they already live? The reason it went extinct was persecution. So the bird was shot. So, by the middle of the 19th century, the birds were extinct in England, extinct in Scotland, and were only found in a small population in Wales, which in the 1930s was believed to only include possibly a dozen individual red kites in the whole of the UK.
Harry - Bring us up to speed then, Will. When was the reintroduction program introduced?
Will - So, in 1989, a number of sites were identified, first of all. And the really important thing was to make sure the birds would thrive where they were introduced. So a lot of work was done with local landowners and people who lived in the area to make sure the birds would be welcome. And two sites were found. One in Scotland, in the Black Isle, and one in the Chilterns, and the Chilterns was the project I was involved in. And originally birds were introduced from Sweden and then later on, birds were introduced from Spain. In both Scotland and in England, 93 birds were introduced over a five year period from 1989 to 1994.
Harry - And at what point, as a conservationist, do you start to say this - being the first attempt to reintroduce a species in the UK - when do you say it is a success? You know, are there points along that five year period where you start to get worried that you've chosen the wrong location or that this just isn't gonna work?
Will - I guess the definition of success is the population is self-sustaining. So the population will have enough offspring that you don't need to introduce any more birds. And so you are not taking birds away from other parts of the world. And that was pretty clear fairly early on in the Chilterns population that the birds were successfully breeding. And also that the offspring were fledging and were themselves making new nests.
Harry - There was a hiccup along the way though, wasn't there? Because I know that the Swedish population had different ideas in mind to what the conservationists had.
Will - Yes the red kites are fascinating species found over a huge area and some of the birds are migratory. So, some of the birds in Sweden will naturally migrate to Spain in the winter and then fly back to Sweden for the breeding season. And in the early years of the Chilterns population, some of the birds left after being introduced and didn't come back and it's not entirely clear why. It might be that they were genetically programmed to migrate as their parents had been, or it might even be that the red kites are very social birds. They tend to go to areas where there's a large population. And so in the following years, a large number were introduced together.
Harry - And today, as we've been saying, it has been a success. It's not just been a success, it's a roaring success really!
Will - It's difficult to estimate the numbers now. In the early part of the 21st century, we reached the point where it just wasn't physically possible to visit all the nests, because the program was being so successful. So a conservative estimate would be there's a thousand breeding pairs in the Chilterns now. It's actually such a success that we're now at the point where breeding birds from the Chilterns have been introduced to other areas, including some taken back to Spain, which makes the whole story go full circle.
Harry - I've come down from Cambridge to see you. And we are sat in your garden in London, looking into the skies. Now, apart from a few airplanes, you're not gonna see any red kites here are you? And it's the same in Cambridge, I would've said. So when you mention that before red kites used to be present across the whole of the UK, are there still areas that they're not making it to, or why aren't we seeing them I guess here?
Will - We certainly should see them in East Anglia. And there are some breeding pairs in Suffolk and you do occasionally see the birds in Hertfordshire. So there's no reason why they shouldn't be here. Buzzards are very successful in Cambridgeshire. Again, it is that social nature. There's a fantastic word, which is 'philopatry'. The birds tend to nest near where they're born and there is that local effect still. And the hope is they will spread. Red kites have gone from being globally threatened and extinct in England to a situation where the Chilterns now have more than 10% of the world's population, which is phenomenal. So the fact that the UK can take part in conservation of internationally threatened species is significant, but I think more interestingly is the effect that the species have on the environment. So red kites, as a carrion feeder, will compete with buzzards, with crows, with magpies, and there is talk of Crow numbers and magpie numbers being too high. And if the introduction of red kites can help to balance out those numbers, it changes the environment. So red kites are a model in terms of what's possible with reintroductions. We can learn lessons particularly about the importance of paving the way locally to make sure that the species will be welcome, but also learning more about how species that were historically part of our natural world can enhance it by coming back in.