Gareth Huw Davies

Conservation / Environment Blog

The princes’ falcon, hunting free above an English town

One of the Aylesbury pergrines, on its nest above the town, May 2012

There is a deadly hunter roaming free in a normally peaceful market town in southern England.  It’s as if a tiger had taken up residence in an Indian town, albeit one that didn’t threaten people.

I heard it recently, giving a harsh, high, demonic call, then saw it above my head, on a busy Saturday morning, the one alien presence among so many familiar features.

This is a creature supreme in its habitat, at the top of its food chain. There’s nothing between it and a healthy population apart from man and his poisons. But now that that humans are cooperating, there’s no reason why the peregrine falcon shouldn’t become a permanent feature above Aylesbury in Bucks.

The peregrine, large and powerful, with long, broad, pointed wings and a relatively short tail is a bird back from the brink. In medieval times the European nobility that used Peregrines for hunting, (according to the Wikipedia entry) associated the bird with princes in formal hierarchies of birds of prey, just below the gyrfalcon, associated with kings.

That counted for nothing The British population was almost wiped out in the 1950s and 1960s, due to the accumulation of persistent agricultural chemicals such as DDT in its prey (which led to a fatal thinning  in the the shells of the eggs it laid). Once that poison and other pesticides were withdrawn, and a more general persecution ended, the bird’s numbers gradually picked up. Today there are about  1400 pairs in Britain.

This, in general, is a bird of rocky seacoasts, cliffs and hills. The strongholds of the breeding birds in the UK are the uplands of the north and west. And that’s where they are recovering, with little intervention from man, nesting on cliff-ledges, quarry faces and crags. But they have another, less expected, nesting site preference, in as busy a location as you can imagine, in the centre of towns and cities.

One place where peregrines choose to nest is high up on the complicated tracery of cathedrals – they are in Chichester and Norwich and Derby; or on sopme lofty perch on old civic buildings, such as Manchester Town Hall. Some of the 14 or so pairs now in built-up of London nest in the stacks of the old power station on the  South Bank, now the Tate Modern.

In the small town of Aylesbury, they’ve chosen the top of the widely derided, as an architectural feature, 13 storey County (Hall) Tower, built in the 1960s.  Staff from Buckinghamshire County Council have helped them out, in partnership with Aylesbury Vale District Council (AVDC), Bucks Bird Club and local volunteers, by positioning a wooden platform as a nest site at the top of the building, projecting outwards towards the town’s central Market Square, no more than 150 m away.

Last year a pair showed keen interest. The female laid an infertile egg. Encouraged by that promising start, staff in the leisure department of AVDC prepared the nest site once again and, with the help of an anonymous donation, installed cameras close to it. Regularly refreshed images are broadcast on a dedicated page on the council’s website. Viewers can see the bird in great detail. It is blue-grey above, with a blackish top of the head and a black ‘moustache’ that contrasts with its white face. Its breast is finely spotted.

This year, so far, all is going well at the nest site. The female laid three eggs at the end of March, and two hatched at the beginning of May. The third, failed, egg has been removed for analysis.

At the time of writing the nestlings, now fitted with identification rings on their legs by intrepid conservationists from the Bucks Bird Group, are thriving. The camera images show them surveying the rather pathetic remains of several quite large birds, usually eaten down to their heads and legs.

By a supreme irony one of the species this rarest birds of prey has brought back, probably from the countryside several miles from the County Tower, to feed its chicks is a cuckoo, already rare in this part of Bucks, and becoming rarer in recent years. I live nine miles from Aylesbury. I used to hear the cuckoo every day through May. This year I’ve heard it only three times.

Other birds brought to the nest include Arctic tern. The peregrines have spread out some of their catches in a ‘larder’ on a flat space next the the nest. Feral pigeons are favourite prey for peregrines generally, though a wide range of birds are taken, ranging in size from goldcrest to grey heron, according to the RSPB website.

The council’s conservation officers report that these birds, along with others currently being surveyed in Derby, Norwich and elsewhere, are showing behaviour that ornithologists knew little about, such as the birds’ feeding behaviour at night. They fix, from below, on night-migrating species (such as dunnock) illuminated by streetlights, then spear upwards at a deadly speed.

We are familiar with the bird’s famous ‘stoop’, where it spots the prey at distance and, once positioned correctly, falls like a stone on its hapless prey at speeds of up to 180 kph. The swift and agile peregrine must catch its prey on the wing to avoid injuring itself on impact.

Local people are already familiar with red kites, reintroduced into the nearby Chilterns about 20 years ago, soaring languidly over the town. They are mainly carion gatherers, rather than active hunters. Buzzards, too, have moved back into the surrounding countryside within the past 10 or so years. It has taken more active human help for peregrines to re-establish themselves in this and other towns and cities, and the council deserves credit for the work it has done. (One day in May, 2012, AVDC  staged a peregrine day in Aylesbury’s Market Square, erecting information stands and giving passers-by a chance to glimpse  the magnificent falcons through high-powered telescopes, while experienced birdwatchers  stood incongruously in line, scanning the skies.)

There’s been the predictable skirmish in the local press, with some citizens objected to the cost of the operation – tiny, compared with repairing the pavement for filling a pothole. Others cited exaggerated estimates of the number of songbirds taken, even in people’s back gardens, which is dangerous and unliky territory for these fast and hard-hitting falcons. The peregrine must catch its prey on the wing to avoid injuring itself on impact.

In truth cats do far more damage, while the pergrines look for pigeons in the town’s more open spaces, or hunt in the abundant countryside all around the town.  If only they could be persuaded to lay off the cuckoos.


More images and details –