Northern Gannet
Northern Gannet
Morus bassanus
At a Glance
One of the largest seabirds of the North Atlantic, the gannet is spectacular as it plunges into the sea in pursuit of fish. With a spear-like bill and spiky tail, it looks 'pointed at both ends.' Nesting colonies are on northern sea cliffs; one at Bonaventure Island, Quebec, has become a famous tourist destination. In winter off southern coastlines, the gleaming white adults may be outnumbered by brown and patchy immatures; it takes four years for gannets to attain full adult plumage.
All bird guide text and rangemaps adapted from by Kenn Kaufman漏 1996, used by permission of Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Category
Boobies and Gannets, Gull-like Birds
IUCN Status
Least Concern
Habitat
Coasts and Shorelines, Lakes, Ponds, and Rivers, Open Ocean
Region
Eastern Canada, Florida, Mid Atlantic, New England, Southeast, Texas
Behavior
Direct Flight, Flap/Glide, Soaring
Population
720.000
Range & Identification
Migration & Range Maps
Migrates offshore southward along Atlantic Coast, some going around southern end of Florida and along Gulf Coast to Texas. Immatures tend to winter farther south than adults. Many (especially adults) are present in winter far offshore as far north as New England. Immatures and nonbreeders may remain south of breeding grounds in summer.
Description
35-40" (89-102 cm). Huge size, long pointed wings, spearlike bill, pointed tail. Adult is white with black wingtips. Juvenile all gray-brown with white speckles at first, gradually changing to adult plumage over three or four years.
Size
About the size of a Heron
Color
Black, Brown, Gray, White, Yellow
Wing Shape
Long, Pointed, Swept, Tapered
Tail Shape
Pointed, Wedge-shaped
Songs and Calls
Guttural croak or grunt, heard only on breeding islands.
Call Pattern
Flat, Undulating
Call Type
Chatter, Raucous
Habitat
Oceanic; often well offshore. Breeds colonially on sea cliffs. Forages at sea, from fairly close inshore to out of sight of land, but mostly over waters of continental shelf. In cold-water areas in summer, but winters to edge of tropics. Nests on cliffs and ledges of islands, sometimes on steep protected cliffs of mainland.
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Behavior
Eggs
One. Pale blue to white, becoming nest-stained. Incubation is by both sexes, 42-46 days.
Young
Both parents feed young, by regurgitation. Age at first flight 84-97 days. Only one young raised per year.
Feeding Behavior
Forages by plunging headfirst into water, sometimes from more than 100' above surface. Also forages while swimming, submerging head to peer below surface and then diving and swimming underwater. May take food at surface, or may steal food from other birds.
Diet
Mainly fish. Feeds mostly on small fish (1-12" in length) of types that live in dense schools, including herring, sand lance, cod, pollack, menhaden. Also may eat some squid. Sometimes scavenges for scraps and offal around fishing boats.
Nesting
Usually first breeds at age of 5-6 years, and may mate for life. Breeds in tightly packed colonies, with much competition for prime nest sites. Male claims nest territory and displays to attract mate, with exaggerated sideways shaking of head. Mated pairs greet each other by standing face to face, wings out, knocking bills together and bowing. Nest: Site is on ledge or flat ground, often within 2-3 feet of other nesting gannets. Nest (built mostly by male) is pile of grass, seaweed, dirt, feathers, compacted and held together by droppings, used by same pair for years and gradually building up to tall mound.
Climate Vulnerability
Conservation Status
Population declined drastically during 19th century owing to taking of eggs and slaughter of adults; this occurred over much of range, but especially off eastern Canada. With protection, populations began to recover early in 20th century, with increase apparently continuing to present day.
Climate Threats Facing the Northern Gannet
Choose a temperature scenario below to see which threats will affect this species as warming increases. The same climate change-driven threats that put birds at risk will affect other wildlife and people, too.