The food habits and distribution of Northern Gannets, Sula bassanus , off eastern Newfoundland and Labrador

• Published in: Canadian Journal of Zoology
• Main Authors: Kirkham, I. R., McLaren, P. L., Montevecchi, W. A.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1985
• Subjects: Animal Science and Zoology; Ecology, Evolution, Behavior and Systematics; Newfoundland; Funk Island; Labrador Sea; North Atlantic
• Online Access: http://dx.doi.org/10.1139/z85-027; http://www.nrcresearchpress.com/doi/pdf/10.1139/z85-027

The marine distribution of Northern Gannets in the southern Labrador Sea and western North Atlantic Ocean was studied by aerial surveys over a 7-month period in 1981. Gannets were seen on every biweekly aerial survey from mid-April to the end of October. Densities were highest within a 60 km radius of Funk Island, but few gannets were seen offshore outside this radius. Before July, most gannets were seen south of Labrador (52°N), but as the breeding season advanced, gannet densities increased in northern areas. Densities in most areas peaked during mid-July. From 1977 to 1982 we collected food samples from gannets in the colony on Funk Island, Newfoundland. A broad spectrum of prey are taken. Mackerel and herring, prey that are associated with warm water, appear to be preferred owing to their large sizes and high energy densities. Prey occurrence in gannet food samples was associated with the time of spawning (capelin) and migration near Funk Island (herring and mackerel). The northernmost region of warm and cold water mixing appears to be the main factor limiting the northern distribution of gannets in the western North Atlantic Ocean.