ON GANNETS

GANNET WATCH 1981 by Geoff Hogan

From late summer throughout the fall, a common sight off the shores of Prince Edward Island is large white birds (goose—sized) with black wing ends.

At first glance they may be mistaken for large gulls although, on closer inspection, it can be seen that they have a distinctive 'pointed at both ends' look. These are Gannets (Morus bassanus).

If observed at close renge the adult Gannet has a yellowish tinge covering the neck and head, and pale blue eyes. The sharp—pointed bill, adapted for grasping fish, is somewhat longer than the head, and the tail is long and tapered. First year birds are completely dark brown with small white spots, while the two to three year old individuals are intermediate in colour, often with an interesting piebald appearance.

Gannets are the largest seabirds regularly found in the North Atlantic. Their North American breeding distribution is confined to the Gulf of St. Lawrence and eastern Newfoundland. They also nest in the British Isles, Norway and Iceland. Gannets are strictly marine birds whose breeding colonies are located on the rocky cliffs or flat tops of isolated islands or, more rarely, on a mainland cliff. There are six breeding colonies in Atlantic Canada. The most famous of these, an important tourist attraction, is on the towering 400 foot cliffs of Bonaventure Island, Gaspé Peninsula, where 17,281 pairs nested in 1973 (Brown et_al.,l975). Another colony, on Bird Rock in the Magdalen Islands, was once the largest colony in the world with an estimated 110,000 pairs in 1834 (Cramp, 1977). Heavy persecution of this colony by man in the nineteenth century drastically reduced its size and in 1973 there were 4,527 pairs nesting there (Brown et_al,, 1975).

Although Gannets historically have never nested on Prince Edward Island they are common transients off our shores during the spring and fall. Single individuals or small groups can be observed as they search for fish such as mackeral and herring. In spring the Gannets migrate north to the breeding colonies and in the fall they disperse to warmer waters off the southern United States. Unlike their relatives the cormorants, Gannets are famous for their spectacular dives for fish. Sometimes diving from heights of 120 feet, they send up sprays of water as they plunge beneath the surface. This is especially exciting to watch if many birds are diving tigether on the same school of fish.

In order for members of the Natural History Society to View the migrating Gannets, a field trip will be held Saturday, October 10 on the Wood Islands, P.E.I. to Caribou, N.S. ferry crossing. Cars will be left at the Wbod Islands dock during the crossing. Details of the time of departure can be found in the 'News and Notes' section of this issue. Anyone interested in taking the Borden, P.E.I. to Cape Tormentine, N.B. ferry crossing on the same day is encouraged to do so as the count results can then be compared. In addition to Gannets other sightings may include: migrating passerines, sea ducks, gulls, cormorants, loons,seals and porpoises., The trip is scheduled regardless of weather so dress accordingly. Binoculars are highly recommended. For more information contact: Geoff Hogan, Biology Dept., U.P.E.I., 892-4121 (ext. 170).,

References: Brown, R.G.B.; D.N.Nettleship; P.Germaine;C.E.Tull; and T.Davis. 1975. Atlas of eastern Canadian seabirds. CWS cat. no. cw66-44/1975, Ottawa 220p.

Cramp, S. 1977. Handbook of the birds of Europe, the Middle East and North Africa. The Birds of the Western Palearctic. vol.l. Oxford Univ. Press. London 722p.

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