The Northstone Materials Division set up a database some three years ago to assist in recording the wildlife found at our quarry locations for biodiversity purposes.
Since its inception, peregrine falcons have featured on it. They have been recorded at our quarry locations at Carrickmore, Croaghan, Ballymena, North Down, Carmean and Mountfield. Nesting and breeding success has been recorded at Ballymena, North Down, Carrickmore and most recently in June this year at Carmean (a limestone quarry), where two downy chicks were spotted in an abandoned raven’s nest on the quarry face.
The peregrine falcon (Falco peregrinus) is an impressive bird with a slate grey back, white front with black barring, and a dark head with white cheeks and black moustachial stripes. The female is bigger than the male. It has a wingspan of around one metre.
The peregrine is a bird of prey and it takes a wide range of other birds in the open, often after a spectacular closed-wing drive from way above the target bird. Estimates of the speed of a stoop vary from 150 mph (British Trust for Ornithology) to 240 mph (various other web sources). Whatever the speed, it is fast. If on target, the blow delivered is usually sufficient to kill the prey outright in mid-air. They will usually predate medium sized birds such as pigeons, jackdaws, duck and game birds.
From near extinction in the 1960s due to a combination of persecution and cumulative poisoning associated with the then large-scale use of insecticides, peregrine numbers have recovered to around 1400 breeding pairs resident in the United Kingdom. The current peregrine population in Northern Ireland is estimated to be seventy breeding pairs.
Its natural haunts are uplands and rocky coasts with cliffs for nesting. Its recovery has been greatly helped by its taking to man-made cliff-like nesting sites as diverse as window sills on high rise buildings and ledges on quarry faces. Up to 40% of nest sites in the Province are in quarries.
On the day they were identified at Carmean, the peregrines’ mewing calls were heard first; the female then flew over with around twenty mobbing jackdaws trailing in her wake. The male gave away the nest position by calling from his perch just above it. The young were large and appeared to be well-fed, no doubt from dining on some of the scores of jackdaws that nest in the numerous cracks and crannies of the very same quarry face. Such feeding should stand these young peregrines in good stead as around half of all birds of prey die within their first year of life.
Peregrines are still persecuted in the Province. The Northern Ireland Raptor Study Group (NIRSG) reported in November 2010 that seven peregrines were known to have been killed by poisoning or shooting that year. The peregrine is protected under The Wildlife (Northern Ireland) Order 1985. It is a Schedule 1 bird protected by special penalties at all times.
NIRSG monitoring results have shown a 20% decline in the number of breeding pairs of peregrine in Northern Ireland in less than 20 years and the number of young successfully fledging has declined by 35%.
Our quarry managers closely monitor nesting peregrines during the breeding season to avoid any disturbance to the birds. Over time, the birds become habituated to the regular activities of an operating quarry and take the presence of the excavator, dumper and quarry personnel in their stride.
It is against this background that the Materials Division is especially pleased that our quarries have for many years provided safe nesting havens for such splendid birds.
