Habitat
Cliff-nesters, although may be some local variations in nest sites.
Geographical spread
The most widespread bird species in the world, breeding in every
continent other than Antarctica. More than 25% of the European Union's peregrine population
breeds in the British Isles.
Current population
RSPB annual monitoring state 800,1,000 breeding pairs in the British Isles
(BBC Wildlife, October 1987). In 1991 the population had increased to 1,100 breeding pairs
(BBC Wildlife, January 1996). There are an extra 99 pairs in N. Ireland and 265 in the Southern
Ireland (figures from the British Trust for Ornithology).
Status
Undergoing great recovery.
Size
Length 15-19inches; females are larger than males.
Weight
Females aprooximately 1100g, males approximately 680g.
Average life expectancy
10 years.
Normal diet
Carnivorous. Other birds including starlings, collared doves, oystercatchers and
pigeons. Peregrines dive onto the prey from above at speeds reaching 150mph.
Normal lifestyle
Solitary and aggressive outside of the breeding season. Adult birds normally
pair for life and may use traditional nest ledges that have been occupied for hundreds of years.
Peregrines return to their breeding sites in late winter and paired birds hunt together. Peregrine
pairs occupy a breeding territory with a radius of less than 1km, but will attack intruders over
a radius of a further 2km. the male begins feeding his mate and will take over the main role of
food provider. The nest is a rudimentary scrape in the ground. Females incubate 3-4 eggs but
begin hunting again once the chicks are 3 weeks old. At 6 weeks the chicks start flying and
learn to hunt by watching their parents and by coaching. The parents often lead the young in
mock chases and drop food from above for the young to catch. The young will leave their
parents before the next autumn and face a dangerous few months own their own for the first
time.
Previous geographical spread
In Britain Peregrines which were once widespread in England,
Wales and Scotland had been all but exterminated in most places by the 1960s.
Reasons for decline
Combination of persecution and DDT.
During the war in 1940 the Secretary of State for Air issued an order for the destruction of
Peregrines and their eggs, because the Royal Air Force saw them as a threat to carrier pigeons
whose leg-borne messages were often vital. Although the order was only issued for a few
counties there was widespread killing and about 100 were killed each year until the expiry of
the order in 1946.
In the 1950s and 1960s the use of DDT and other organochlorine chemicals contaminated their
food supply and led to a large number of Peregrine deaths (as well as many other animal
species) and caused eggs to become so thin that they broke when a parent sat down to warm
them.
Peregrines have also been killed for sporting interests and the collection of eggs and young by
falconers. In 1963 the Peregrine population in Britain reached an all time low of 280 breeding
pairs (BBC Wildlife, Jan 1996).
Since the late 1960s however, the numbers of Peregrines has been steadily increasing and by
the 1980s were nearly as numerous in many parts of Britain as they were before their
persecution and poisoning began.
Conservation projects
In Bristol in 1990 a Peregrine pair were found breeding in the
woodland quarry beneath Clifton Suspension Bridge. Volunteers from the Bristol Ornithological
Club (BOC), The Hawk and Owl Trust, the RSPB and the Avon Wildlife Trust mounted a round-
the-clock guard. BBC Wildlife sponsored a portable phone system and the eyrie was protected
from raiders. Since then the programme has continued to monitor the birds.
These birds are no longer particularly threatened and numbers are back up to those before
DDT.
File last modified Thursday, October 3, 1996