#18 Red Kite by Doug Simpson
Meet Doug Simpson MBE, Project Officer for Red Kite reintroduction in Yorkshire!
Doug has been interested in wild bird protection and more general nature conservation since the late 1970s, for which he was awarded an MBE in 2007. This interest began with the monitoring of Peregrine Falcons in the Yorkshire Dales, where they were making a comeback from the disastrous effects or organo-chlorine pesticides introduced into their food-chain through their widespread use in agriculture. One of the highlights of this monitoring was the discovery that a pair of Peregrines had settled to breed at Malham Cove – a site which is now the base for a very successful viewing facility each year - organised by the Yorkshire Dales National Park and the RSPB. Doug still takes part in Peregrine monitoring at 2 locations, but since 1999 has been involved with another spectacular species, most notably as Project Officer for the reintroduction of Red Kites into Yorkshire.
Doug’s chosen species is the Red Kite Milvus milvus. Red Kites are large birds of prey with a wing-span of approximately 1.5m and a length of around 60cm. They are instantly recognisable from their long forked tail which distinguishes them from Common Buzzards, the only other birds of prey around this size with which they might be confused. Red Kites became extinct in England and Scotland more than 150 years ago due to human persecution. Their numbers have, however, recovered dramatically following several reintroduction projects. Meanwhile, a residual population in Wales is also well on the road to recovery, under its own steam, having benefitted significantly from nest protection efforts to guard against egg-collectors. You can find out more about the Red Kite on the NBN Atlas.
Yorkshire was the fifth region in the UK to host a Red Kite reintroduction programme. The Project consisted of a partnership involving English Nature (as it then was), the RSPB, Harewood Estate, and Yorkshire Water – the latter having been the catalyst for the project through making available a significant sum of money, sourced from Landfill Tax Credit. A further financial contribution was made by an East Yorkshire waste management company – a highly appropriate source given the scavenging habit of kites and the title of ‘nature’s bin-men’ which they are sometimes given. Harewood Estate provided a safe location for the release-pens and a handy base for the project.
Red Kite (c) Doug Simpson
A total of 69 birds were released over the period 1999 to 2003. They were sourced as chicks from wild nests in the Chilterns at an age of roughly four weeks, a population which itself had been the product of a reintroduction programme. It had been so successful that it was able to provide Yorkshire with sufficient young birds to establish a population here without risking any significant effect on its own progress. Young birds were only taken from nests which contained three or more chicks. Usually the smallest bird – maybe the one least likely to survive if there was a shortage of food – was taken though, unwittingly, this produced a significant imbalance of sexes. Males are slightly smaller than females and the testing of blood samples from the first 20 birds released in 1999 subsequently revealed them to be 14 males and only 6 females.
The young kites were kept in large pens (20’x8’x8’) until they were ready to be released at the age of around 8 weeks. During this period, they were fitted with wing-tags and radio-transmitters and underwent detailed medical checks. An official release event was fixed for a date in early July 1999. However, several of the birds were ready to go before this and were secretly released. In the event, the presence of some of them flying above the gathered dignitaries at the official launch really made the day!
“Radio-tracking showed that several of the birds released in 1999 had made their way eastwards to the southern end of the Yorkshire Wolds...so forming the nucleus of an apparently healthy and totally unplanned East Yorkshire population!”
The fitting of numbered wing-tags and radio-transmitters enabled the birds to be identified and tracked. There is a UK colour-coding system whereby the colour of the tag on the left wing indicates the area of release/origin. The colour of the tag on the right wing denotes the year of tagging - Yorkshire was allocated orange as its area identifier. The year colour for 1999 was black, so our first Yorkshire releases had an orange/black wing-tag colour combination. The tags are most easily read when the birds are perched, this being relatively straightforward using a tripod-mounted scope.
The radio-transmitters were mounted on the bird’s back using a harness made of Teflon ribbon. Each one operated on a separate frequency, enabling them to be tracked individually. This facility provided much valuable information about their locations and enabled dead ones to be located as quickly as possible – vital in establishing the cause of death. The transmitters gave off a different signal pulse rate according to whether the bird was vertical, as when perched, or horizontal as when flying or on the ground. The signal strength also varied according to the bird’s movements – a totally uniform signal strength from a bird giving off a horizontal indicator signal would be a strong indication that it was dead on the ground. In such a case signals would be checked from 2 or 3 locations and their precise compass bearings traced onto an OS map. Where the lines crossed was the likely location of the bird.
Red Kite showing its tags (c) Doug Simpson
The tracking devices consisted of a receiver and hand-held directional Yagi aerial. Doug soon worked out which were the best places to scan from, high points which provided a good chance of picking up signals, especially from birds which had moved away from the release area. The effective range of the tracking facility varied considerably according to the nature of the terrain and the location of the bird. Radio-tracking showed that several of the birds released in 1999 had made their way eastwards to the southern end of the Yorkshire Wolds. This was an unexpected development – the more so because some of them settled to breed, so forming the nucleus of an apparently healthy and totally unplanned East Yorkshire population!
‘We always sought to avoid duplication of radio frequencies known to be in use on kites from other areas. However, it was impossible to avoid those in use on other species – fitted by other agencies. On one occasion I was confident that I had located two missing kites up Wensleydale, though the closer I got the more puzzled I became as to how I could be picking up signals suggesting that they were perched whereas there were no trees in the locality. It transpired that I had been tracking Red Grouse which had been fitted with transmitters by the Game Conservancy!’
An unfortunate downside to the reintroduction process has been the deaths of birds through illegal activities such as shooting and poisoning. It is almost impossible to establish who has been responsible for deliberately targeting the birds with firearms or placing poisoned baits out in the open countryside on which they have fed, with fatal consequences. At least 32 are known to have been poisoned and 15 have died after being shot, 2 of the latter having apparently been shot whilst sitting on their nests. A significant proportion of the casualties have occurred in North Yorkshire, and these known figures are undoubtedly just the tip of the proverbial iceberg. Rat poisons also pose another threat to Red Kites, which find and consume rats which have died in the open after being poisoned. This poison builds up in the bird until it reaches a fatal level. Eighteen kites are known to have died in this way, whilst many more will have gone undetected.
Monitoring
On a more positive note, it would appear that the reintroduction process has been a resounding success – so much so that it is no longer possible to keep up with their numbers. They are big birds and easily seen. They are readily identifiable and have prompted many people to develop an increased interest in wildlife in the countryside. This was nicely summed up in a couple of comments we received that their presence had added an extra dimension to walks in the countryside and that the sight of one from the 36 bus into Leeds on a Monday morning got the week off to a good start! More information can be found on the Yorkshire Red Kites website.
Further information and acknowledgements
NEYEDC would like to thank Doug for his time and expertise in helping to create this blog. If you’d be interested in contributing a piece for the series, contact Lucy at lucy.baldwin@neyedc.co.uk. To find out more about biological recording, see the Naturalists page on our website.