The magnificent frigatebird can be easily
recognized in flight, even from a distance,
thanks to its large head, long, pointed, narrow
wings, and forked tail. If there is any doubt
about the bird's identity, a view that includes
the bright red gular sac and white bill (of the
male) will confirm that it is a magnificent
Frigatebirds are the only
seabirds to have obvious, significant differences
in plumage between the sexes. Male magnificent
frigatebirds are entirely black except for brown
inner secondaries on the upper wing, faint purple
gloss on the head, green on the neck, scapulars,
and upper wing, and a red inflatable throat pouch
(gular sac). Their legs and feet appear black or
grayish. Females are also entirely black, but
have a white chest and white and tan markings on
the wings. Their legs and feet are flesh-colored
or pink, and they lack a gular sac. Immature
magnificent frigatebirds have a white head and
chest while the rest of the body is black. Their
legs, feet, and bill are light-bluish gray.
Magnificent frigatebirds measure 35-45 inches
in length, have a wingspan of 85-96 inches, and
weigh 2.4-3.5 pounds. Females are, in general,
15% larger than males.
Their wings are so large that flying is nearly
effortless. They take advantage of updrafts and
can glide for long distances without beating
their wings. They use their long, forked tails
for maneuvering. They are one of the only birds
with the ability to ride out a hurricane's strong
winds. Their short legs and small feet make them
awkward on land, however. Moreover, the plumage
lacks a waterproof coating, so the bird becomes
waterlogged and cannot fly if it sits on the
water for more than a minute or two.
The breeding range of the magnificent
frigatebird includes islands throughout the
Caribbean, tropical areas along the Pacific and
Atlantic coasts of Middle and South America, and
the Galapagos Islands. Outside the breeding
season, this species' range is even more
expansive, with individuals regularly found along
the Pacific coast from central California, south
to northern Peru, and along the Atlantic coast
from North Carolina, south to northern Argentina.
During storms, magnificent frigatebird
individuals may be blown exceptionally long
distances off course, and have been spotted as
far north as Alaska and Canada, and as far east
as the west coast of Africa, and even Great
Britain, the Netherlands, and Denmark.
This species breeds in stands of mangroves on
coral reefs, and amongst deciduous trees and
bushes on dry islands and along coasts. During
breeding, foraging may take place over shallow
water within lagoons and coral reefs, or over
deep ocean. Outside the breeding season, it can
usually be found over warm coastal and offshore
waters, and roosts in trees on tropical and
subtropical coasts and islands.
Magnificent frigatebirds feed primarily on
fish, squid, jellyfish, and crustaceans, but the
diet can vary greatly depending on availability
and preferred hunting technique. The three main
hunting techniques are dipping, kleptoparasitism,
and opportunistic feeding.
When dipping, the bird glides just above the
water and skims the surface with its beak to
catch fish. It can only dip about 6 inches deep,
however, since it cannot allow its feathers to
get too wet. Kleptoparasitism, the stealing of
another animal's food, has earned this species
the nickname "Man-'o-War," a reference
to the type of ship used by pirates. The
frigatebirds will chase another bird (usually a
gulls gannet, tern, or booby) until the
"victim" is forced to disgorge its
food, which is caught in mid-air by the
frigatebird. It may also catch the other bird by
the tail feathers and shake it until it releases
its food. Opportunistic feeding involves eating
garbage, young turtles at hatching, and otherwise
taking advantage of all available food sources.
Magnificent frigatebirds eat fish scraps
discarded by boats, offal (discarded parts of
animals unfit for consumption) from
slaughterhouses, and other garbage, and have even
been knwon to steal food from the hands of
During the breeding season, which runs from
August to October, male magnificent frigatebirds
congregate at display sites. They inflate their
gular sacs, which, while inflated, can get so
large that they obscure the bird's head, rapidly
vibrate their wings, and sit back on their tails.
Females then inspect the males. Magnificent
frigatebirds form monogamous pairs each breeding
season once females have selected mates, but
rarely maintain the same partner from season to
Once paired, the male gathers twigs and other
nest-building materials while the female remains
at the display site and builds the nest there.
Nests are usually constructed at ground level,
but are sometimes built in a low shrub or tree.
The nest itself is flat or slightly hollow with a
diameter of 9-14 inches.
After mating, a single egg is laid, which is
incubated for 53-61 days by both parent birds.
The chick, which takes around 22 weeks to fledge,
is brooded and fed by both sexes for the first
7-12 weeks, after which time the male leaves and
the female assumes full responsibility for
raising the chick, providing food until fully
fledged, and then for a further 4-9 months.
Because female parent involvement continues for
much longer than male parental involvement,
females only mate every other year, while males
mate every year.
genus & species Fregata magnificens
Animal Diversity Web http://animaldiversity.org/accounts/Fregata_magnificens/
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