A Winter’s Tale: The story of one man, a metal detector, and the mighty Peregrine Falcon
It all started at Craig Cerrig Gleisiad in the Brecon Beacons on the 3rd of March 1997. As a bird ringer and a keen nest recorder, finding and monitoring nests for BTO’s Nest Record Scheme, I was pleased to find the winter was on its knees, and the long-awaited spring promising some action once again. I was searching for a Raven's nest by scanning the cliffs above the towering ancient glacier of this formidable mountain monument, and soon spotted the mass of sticks and heavy green stains where the nest was situated. It was quite a steep climb to the nest which was tucked under a small overhang and still in the process of being built. Whilst up there I noticed that this ledge was a favoured winter roost site of Peregrine Falcons, and at some time in its very long history had been used for nesting by Peregrines as well.
I looked down to the grass bank beneath and the usual sight of Peregrine activity greeted me -feathers of previous kills, bleached bones of birds long past, and quite a few pellets (Peregrines, like other birds of prey and owls, regurgitate bones and other indigestible material in pellets). I climbed back down and started squeezing through the pellets, thinking that I might be lucky enough to find a bird ring inside, and was quite amazed when a British ring popped out. Fantastic, I thought. I squeezed some more, and, incredibly enough, out popped a Danish ring! It gets better, believe me…
I visited another Peregrine site the following day and found a Dutch ring. Then, a thought hit me, what if I searched at these sites with a metal detector? It was getting close to the Peregrine nesting season, so I had to leave it until the following autumn/winter, when they had finished breeding, before I searched again, this time armed with a cheap metal detector.
It was a long time before I found my next ring but thereafter the results were outstanding and quite phenomenal. A few other friends joined me in this pursuit and it has now grown into a continuing and on-going study, resulting in a number of scientific papers, chiefly on the racing pigeon/Peregrine interaction. I was involved in or found just under half of the ring recoveries listed below:
BTO rings: Peregrine Falcon, Blackbird (2), Dunlin, Jay, Starling (2), Greenfinch (2), Great Tit (3), Chaffinch (2), Dipper (6) – relatively high numbers of Dippers wear rings, Reed Bunting, Blue Tit (2), Sand Martin, Song Thrush, Stock Dove and even one of my own ringed Whinchats.
Rings from abroad: Starlings from Denmark, Latvia, Lithuania (5), Russia, Estonia, the Netherlands and Sweden. Redwings from Belgium (4), France, Sweden and the Netherlands (2); A Dutch Song Thrush; Blackbirds from Germany, and the Netherlands (2); Fieldfares from Norway and Finland; a Black Headed Gull from Lithuania; Common Terns from the Netherlands and West Africa; a Chaffinch from the Netherlands; a Sandwich Tern from Sweden; and Chaffinch, Woodcock and Sand Martin from France.
This may make you think that it’s an easy way of finding rings, but the amount of time, work and effort that went into the collection of this information was incredible. Many Peregrine sites were visited over the winters in South and Central Wales, most sites yielding no recoveries apart from racing pigeon rings, so it was one hell of a moment when I finally found a ring from a wild bird. Imagine it; you’re on a windswept moorland crag, a wall of rock stretches out before you and you’re looking for a tiny ring that's lost amongst the stones and crevices of heather and nettle laden ledges. You’re looking for the smallest of metal objects in a vast, seemingly impossible environment. Every time you hear that beep, you’re hoping for that shine of silver metal, but not today…then out of the blue you find one…what a moment it is! It’s the ultimate result of so much hard work and I now wear the rings that I have found on my binocular strap; Real trophies, national treasures - every one of them giving me the greatest of pleasures at the time.
Apart from a quantity of rings that were unidentified (probably from exotic escaped birds like parrots), the recoveries of racing pigeon rings were very impressive. Our earliest ring was from1906 with many from the 1910s to the 1950s. They tailed off quite dramatically in the 1960's due to the impact of DDT on Peregrines , but then it picked up again in the mid 1970's. We found rings from all four nations of the UK, Rollers (show doves), rings from France, Belgium, the Netherlands, Spain, Germany and Poland. We even found a few of the Queen’s birds (if you didn't know, she too keeps pigeons) which have ER on the ring.
It may not be every-one’s cup of tea, but being a bird ringer I know that every ring recovery is important for the work we do. I always check any dead birds I see on the side of the road and, if there's a chance of a recovery at a bird of prey nest site, then I think it's well worth putting in the time and effort to find the information (always outside of the breeding season of course). Only a small proportion of birds that are ringed are ever recovered, so every recovery is vital to our knowledge of bird survival and movements.
I still get out with the detector each winter in Devon, although not as intensely as I did in Wales. It keeps me sharp for the season ahead. Unfortunately most of the coastal Peregrine nests in Devon are on steep sea cliffs, so it’s very difficult to get below them. I am still finding rings, though - my latest addition was a Great Spotted Woodpecker recovery in February 2011 from a site on Dartmoor. A great moment… the saga continues. They are out there, you’ve just got to go out and find them. I’ve got a few more planned this winter, and, hopefully, a new recovery will be found there somewhere. And if I do find one, the best thrill will be that I won't have a clue what the bird is until I receive the information back…well worth the wait!
The best recovery for me? I was up at a site in the Welsh mountain valleys tapping pellets on the base of the detector when I heard that familiar signal. I squeezed out the pellet and found a ring numbered L101310 – it turned out to be a Common Tern nestling ringed on 24th June 1998 at Zwolle, De marslandens, the Netherlands and recovered in Abertillery, South Wales - 637km from where it was ringed 92 days previously. I was very excited and wrote to the ringer, enclosing some photos of the site where I found the ring. He wrote back with some photos of where he ringed the bird, nest, eggs and chicks on a pebble-dashed factory roof in Holland.
If you want to keep fit this winter, put a metal detector on your Christmas wish list, stretch those legs and find those recoveries that lie undiscovered and which can add yet more knowledge to our understanding of the birds we ring. It's a great winter sport, and I can guarantee, you won't be disappointed.
Migration blog (3rd – 9th September)
With the first days of Autumn upon us and the breeding season over for many species, the focus is now on preparing for the coming winter months.