News

Monday, 26 May 2008

Peregrines on Canterbury Cathedral - another update

Background to the recent history of peregrines at the cathedral - A pair of peregrines took up residence at Canterbury Cathedral in 2007, roosting on its cliff-like masonry and making inroads on the feral pigeon population. Peregrines do not normally breed until their second or third year, so it was a little disappointing but not really surprising when they failed to breed in 2007. However, following discussions with the cathedral authorities the RSPB was able to set up a nesting ledge and webcam, which will enable the cathedral's one million visitors to watch live transmissions of activity at any future nest. Similar schemes have already been very successfully organised in recent years at Exeter, Derby, Salisbury and Chichester Cathedrals. Canterbury residents would be very proud to see their cathedral added to this expanding list of prestigious nest sites.

Hopes were moderately high that the peregrines would nest in 2008. However, observations through the winter of 2007-8 indicated that the male bird was alone, and, for the second year, plans for an Aren't Birds Brilliant! project have had to be postponed. A further complication is that heavy winter rain had revealed serious leaks at the west end of the cathedral roof, and emergency repairs are planned for this summer. Unfortunately, this means that there will be a greatly increased level of activity in the area where the nestbox was placed, so the success of any breeding attempt would have been compromised anyway. The nestbox, which in any case was not being used for roosting, has now been removed to discourage birds from taking any interest in this part of the roof and will be re-erected in an area that is going to be free from disturbance for the next few years.

However, in May 2008, a female was seen consorting with the male, but it was felt that it was now too late in the season for the birds to be nesting. But soon afterwards cathedral staff disturbed a bird from a clutch of two eggs that had been laid inside a pinnacle on top of Bell Harry Tower (the high tower near the centre of the cathedral). Previously, all interest had centred on one of the western towers, so this discovery came completely out of the blue. It is not known when the eggs were laid, but observations suggest that the female may not be incubating regularly, and that this nesting attempt may well fail. Birds of prey are long-lived, and may not breed successfully until they are several years old: as it was assumed that this pair would be young birds, failure in 2008 is not particularly surprising, but the chances of success in 2009 are much higher. The RSPB is still investigating the possibility of establishing a limited viewing opportunity for visitors this summer, probably confined to live CCTV pictures of activity at the nest. The rest will be down to the peregrines themselves.

A pair has bred on Dover cliffs since 1989, and numbers have increased painfully slowly since then, with nest sites ranging from traditional cliffs to man-made structures such as pylons and quarries. About 15 pairs are now thought to be nesting annually in Kent.

Peregrines in Kent were systematically persecuted during the Second World War as it was feared that birds nesting on the chalk cliffs were killing carrier pigeons flying back from the battlefronts with secret messages. Then in the late 1950s and 1960s they were very hard-hit by the use of toxic, persistent, agricultural pesticides, and the species became extinct in the county. Recovery has been extremely slow, not helped by the antipathy of some pigeon-racers, who have been known to destroy nests and kill adults, and we must now wait with bated breath to see if the birds currently terrorising Canterbury's pigeons are going to settle down and nest.