Return of the Peregrine

by: Myrtle Bateman
September 1982

The peregrine falcon has been the favourite of falconers for over 3000 years because of its speed, strength, and agility on the wing. During the Middle Ages when falconry was at its height, peregrines were the birds of princes while goshawks and kestrels were flown by lesser mortals. Peregrines in Europe maintained healthy populations despite the depredations of falconers (who took young from the nest), egg collecting and killing by pigeon fanciers. Serious declines in populations did not begin until widespread use of organochlorine pesticides following World War II.

That decline has been almost worldwide. As early as the 1950's, the reduction in the number of active nests was considered serious in Great Britain; by 1965 population declines were reported from most of Europe and North America south of the tree line. Today the peregrine falcon has world recognition as an endangered species.

Work over the past decade has clearly shown that organochlorine pesticides, primarily DDT and the dieldrin group, picked up through the birds' food, caused the decline in the number of successful peregrine nests. A ban on the use of those pesticides in the early 1970's has resulted in relatively low levels of chemicals in the peregrines' food species throughout most of Canada.

In 1970, the Canadian Wildlife Service (CWS) began a program to breed peregrines in captivity. CWS has two objectives; first, to re-establish the species in areas where it no longer nested; and second, to increase native populations in areas where severe reductions have occurred. Before re-introductions take place, it must be established that pesticide levels in the prey are low enough to allow survival and successful breeding, and that food and suitable nesting habitat are available. Peregrines have now been released at Selected sites from Alberta to Quebec. In 1981, CWS released 102 birds across Canada.

Since 1955, when the last active nest was observed in Nova Scotia, all peregrines recorded here were probably transients from the Arctic breeding population, a different subspecies. Peregrines were never abundant in the province. Only five nest sites had been recorded, all on the cliffs around Minas Basin, Minas Channel, or in the Upper Bay of Fundy. So a cliff site near Advocate, Cumberland County was selected for a release during the summer of 1982. On July 7, three nestlings - two males and one female - arrived from the breeding facility at Wainwright, Alberta. This facility, jointly funded by CWS and the province of Alberta, raises all the nestlings for release across Canada from adult birds kept in Wainwright. Nova Scotia's three birds were 32 days old when they arrived and still had a lot of down feathers.

The secret of successfully releasing birds to the wild is to ensure that young birds are isolated from humans - especially so they do not recognize humans as the source of their food. For this reason Wainwright birds are raised under the supervision of television cameras. They are transported in an enclosed box and at the release site they are kept in a "hack-box" at the top of the cliff. This hack-box has a grill on the front that allows the birds to see their new territory. After 12 days in the box, the peregrines were capable of strong flight at which time the front of the box was opened. AT feeding time, dead chickens and cotournix quail were dropped through a pipe from behind the box to prevent the birds from seeing the sources of the food.

Until they can hunt for themselves the young peregrines will remain in the area of the release, and return to the box to feed on quail and chicken put out for them. To keep them wary of humans they must be scared away before the food is left. It is expected that the peregrines will migrate in September and hopefully return to Nova Scotia in the spring of 1983.

Mortality of peregrines less than one year old is very high, about 70 percent. Predators like great horned owls and large raptorial birds will take peregrines. Many more die from accidents suffered while learning to catch their food. to establish a breeding population, it is necessary to release many birds in an area. Therefore releases in Nova Scotia are scheduled for at least the next four years. Across the Bay of Fundy at Fundy National Park, New Brunswick releases are also taking place.

Peregrines released near Advocate in July 1982 have a standard monel metal band on their left leg and a red one on their right leg. The location of any sightings of these birds should be sent to Myrtle C. Bateman, Wildlife Biologist, Canadian Wildlife Service, P.O. Box 6227, Sackville, New Brunswick, E4L 1G6.

IMAGE:  The "hack box" gives the young peregrines an opportunity to become familiar with their new home.

IMAGE:  Hopefully female peregrine falcons will become summer residents in Nova Scotia.