Falcon facts

Peregrine falcon facts

The Peregrine is the largest falcon breeding in the UK.
Numbers in the UK have recovered to about 1,500 breeding pairs, from the low point of the 1960s when their numbers plummeted due to the use of the pesticide DDT or its degenerate DDE (Dichloro-diphenyl-trichloroethane). This chemical was picked up by the birds which ate prey that had fed on treated grain and caused them to lay thin-shelled eggs that would fail to hatch or break during incubation.
Since the use of DDT was banned peregrine numbers have increased to pre-DDT levels but are now under threat from egg collectors, thieves taking chicks to sell on to falconers and from those wanting to prevent falcons taking their racing pigeons.
The recent colonisation of city centres and urban areas has happened due to the fact that tall buildings mimick their natural crag or cliff environment. Cities also have an almost inexhaustible food supply due to large populations of feral pigeons.
Tall city centre buildings provide the birds with safe nesting sites and the young produced on these sites will allow the re-colonisation of other areas of the East Midlands.
Birds return to the same nest site each year, the longest continuously used site is on Lundy Island in the Bristol Channel that has been occupied since 1245.
Their clutch normally consists of three or four eggs (rarely two or five eggs) and the young are in the nest for about six weeks. Fed by both parents, the chicks grow quickly and by the time they leave the nest weigh over ten times heavier than when they hatched.
The female peregrine is called a falcon and weighs almost twice the weight (up to 950 grams) of the male or tiercel (up to 550 grams).
Peregrines are the fastest animals on earth, reaching over 200 miles an hour while swooping on prey.
A wide range of prey items are taken, mostly in flight. These range from small song birds and pigeons to gulls and ducks.
Birds disperse from the areas where they were bred and often move south. A first year bird ringed in northern Scotland was picked up alive on the Nottinghamshire/ Derbyshire border during its first winter.
Peregrine falcon on the Newton building - photo by Sean Browne
Peregrine falcons on the Newton building - photo by Sean Browne