Geoscience Reference
In-Depth Information
Land, bird, and sea come together dramatically on Bonaventure Island, the largest gannetry in the North Atlantic.
Gannets are ungainly on land because of their short legs and large webbed feet. In the air, however, they are
supremely graceful, using their magnificent wingspan to glide over the wave tops, sometimes for hours, with
only the occasional beating of their wings. This tactic, called “wavehopping,” employs the natural updraft off
each wave crest. It is in their diving and fishing behavior, though, that gannets truly excel. Folding its wings
and diving almost vertically, a gannet seems to drop from the sky like a lead plumb bob. Upon impact, spray
sometimes spouts 3 meters (9 feet) into the air. The gannet is particularly well adapted for this daredevil beha-
vior. Unlike most birds, it has binocular vision (the eyes are positioned so that both see forward simultan-
eously), allowing it to estimate how far below the surface the prey lies. It has no nostrils, and its upper and
lower bill fit tightly together to prevent ingestion of water on impact. Upon diving, the gannet inflates air cells
located between the skin and shoulders and the muscles beneath. These cells act as shock absorbers to cushion
its body from the tremendous force of impact. The dive drives the bird below its prey; it then swims up with its
wings and webbed feet to capture the fish. The great gannet colony on Bonaventure Island is sustained by
mackerel, which migrate into the gulf to spawn at the same time that the young are hatching and the colony's
nutritional needs are greatest.
Sea Meadows, Lagoons, and Dunes
Once around the Gaspé, you enter the Magdalen Shallows, an underwater plateau some 150 kilometers (93
miles) wide, cut here and there by several deeper troughs. Generally, the waters are, as the name would sug-
gest, shallow—some 80 meters (260 feet) deep, though, of course, much shallower near the shore. The Gaspé
Current conveys freshwater from the St. Lawrence estuary, which, combined with the shallow depth, results in
the warmest waters in Eastern Canada. These shallow waters are also the most productive in the gulf region.
