The
Northern Gannet is one of the largest seabirds of the north Atlantic Ocean,
where great nesting colonies can be found on select cliff sites on the
Canadian coastline in summer. At other times of the year, they are scattered
over a wide area across the Atlantic, from as far north as Cape Cod in
Massachusetts, southward to the tropics. Groups of foraging Northern
Gannets are often found where upwelling cold currents concentrate their
favorite fish species. There, Northern Gannets can be seen performing
spectacular plunge dives into the ocean, with high-speed vertical dives
followed by underwater pursuit of their prey. Northern Gannets are
closely related to Booby species, with the Masked Booby and Red-footed Bobby
somewhat similar in overall appearance.
Habitat: During the summer breeding season, they
nest on cliffs. In migration and in winter, they are pelagic, being
found anywhere from near-shore areas to offshore sites far from land.
Diet: Feeds mostly on fish, but will also
sometimes eat squid.
Behavior: Northern Gannets typically feed by
plunge-diving into the water, and swimming underwater to capture fish.
They will also sometimes swim on the ocean's surface, tipping down and
swimming underwater when prey is spotted.
Nesting: Nests in colonies, using rocky cliffs.
The nest is typically on a cliff ledge, and consists of a mound of grasses,
feathers, and seawood, bound together by the birds' own droppings.
Both the male and female will help to incubate the eggs, and both parents
feed and tend to the young. Nesting pairs may stay together for many
years, and often use the same nest site multiple years in a row.
Song: They are most often heard on their breeding
grounds, where birds on breeding colonies give harsh gurgling calls.
At other seasons, they are mostly silent.
Migration: In North America, Northern Gannets
breed in and around the Atlantic coast of southeastern Canada.
Strongly migratory, in winter, North American birds are found along the
Atlantic Coast from Cape Cod southward, and the Gulf Coast.
Similar Species:
Masked Booby and
Red-footed Booby are most similar in overal plumage, but
juveniles especially could also be mistaken for
Blue-footed Booby or
Brown
Booby juveniles.
Conservation Status: Populations of Northern
Gannet plummeted in the 1800s. Birds were shot for food, and eggs were
also collected from nesting colonies. Populations began to recover in
the 1900s and are likely still increasing today, but it's likely populations
are still well below the historical norm. With the population recovery
however, the
IUCN
lists the Northern Gannet as a species of "Least Concern".
Photo Information: Photo taken on February 13th,
2008 - Bon Secour National Wildlife Refuge, coastal Alabama - Terry Sohl