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crested cormorant nests (where the adults were sitting on eggs) and got into a Great Cormorant nest at the west end of the same ledge, approximately five feet from their own nest. Since the latter nest already held three young (approximately three weeks old), it now contained six young, while the central nest was empty. Although the three chicks from the central nest could see their parents standing at their vacant nest, they were unable to return to it because of

the aggressive behavior of the two Double—crested Cormorant pairs separating them. Within a week, the central pair of Great Cormorants began to nest again, despite the fact that their first clutch of young were only several feet away. The three young from the central nest were adopted into the west nest.Shortly after, there were only five young in the West nest, as one fell oﬂfthis very crowded section of the ledge. The remaining five were successfully raised and by July

15 all were flying. The central pair of Great Cormorants raised a second family of 2 chicks which were flying by September 24. The

two pairs of Double-crested Cormorants between the two Great Cormorant nests each successfully raised 3 young to flying age (50-56 days).

Although this storm resulted in many cormorant pairs losing nests, eggs, and chicks we must realize that this is merely one way in which nature ensures that animal populations do not become over abundant in their habitat. Overall nesting success of cormorants at Cape Tryon in 1976 was very good with most pairs raising from 1 to 5 chicks. Cormorants manage to survive despite annual losses by storms and predators. Wehn man intervenes with resulting habitat destruction, pollution, toxic chemicals and disturbance at breeding colonies, their survival may be jeOpardized.

Geoff Hogan

Department of Biology Brock University

St. Catherines, Ontario

Ed. Note: For those interested in reading more about cormorants, the Fall 1976 issue of the "Environeer" has an article on the general life history of our two cormorant species on Prince Edward Island.

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