Sunday, 26 February 2012

Peregrine Travels

Article from Ed Drewitt blog -

Young Peregrine travels from Avon Gorge to the West Midlands

I've been colour-ringing peregrine chicks since 2007 with the help of fellow BTO ringer Ade George, and volunteer climbers from the British Mountaineering Council. In each year I have been building up the number of nest sites we visit to maximise how many chicks we ring. With bird ringing (or banding) it is a numbers game - the more birds you ring, the more likely someone will spot one of 'your' birds and report it. With colour-ringed birds this likelihood increases hugely - while only perhaps 2% of birds with just metal ID rings may be resighted, up to 98% of birds colour-ringed may be recovered.

BX - one of five chicks ringed in the Avon Gorge in 2010. Photo by Ed Drewitt.
With my peregrine work the results can be a little delayed. In the first first few years a peregrine's life is very nomadic as it travels around getting to know the region and no doubt look for a mate. So it's not until a peregrine begins to settle at a nest site at two or three years old that it may be seen and identified by birders.

Of my peregrines that have been re-sighted so far, most have been quite close to Bath and Bristol, near where we ringed them. For example, one was seen with a female partner 15km south of Bristol from where it was ringed two years later; another is now the breeding male at a nest in Bath where it hatched; and a third individual was re-seen later in the autumn at the site where it was ringed and had fledged earlier that year.

Our furthest travelled bird however goes to the following individual. One of the young peregrines we ringed in the Avon Gorge in 2010 was also filmed for the BBC's Springwatch.
He was given a blue colour-ring with black letters, BT (his sibling BX is in the photo above)

He was spotted and photographed by Michael Colquhoun in the Malvern Hills, Worcestershire back in April 2011. This was exciting news and it was great to know one of the chicks had ventured so far. 

BT in April, 2011 - now is partial adult plumage in the Malvern Hills. Photo by Michael Colquhoun
BT's colour ring clearly visible. Photo by Michael Colquhoun.
However, I then had sad news in October 2011 that a peregrine with one of my colour-rings had been found dead by a dog walker not far from KIdderminster in the West Midlands. After exchanging e-mails with local birder Jason Kernohan who met the dog walker and recovered the dead bird, I discovered it was the same colour-ringed individual, BT. 

He had been dead for four days before being found (as indicated by the development of moaggots). He was taken to a vet by the police for an x-ray to confirm he hadn't been shot. He had been found below power lines and seems likely he had died from some interaction with these. 

BT's colour ring. Photo by Jason Kernohan
BT's metal BTO ring. Photo by Jason Kernohan.

Despite this young bird's death I'm pleased we know his final outcome and where he travelled. It helps build up a bigger picture of what peregrines do when they fledge. It's interesting that we've not heard from the other four chicks that were in that same family. Yet we have heard from this individual twice! Hopefully as the other four (assuming they are all alive) begin breeding they will be spotted and identified by myself or someone else watching them. 

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