Frigatebirds |

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Scientific classification |
Kingdom: |
Animalia
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Phylum: |
Chordata
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Class: |
Aves
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Order: |
Pelecaniformes
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Family: |
Fregatidae
Degland & Gerbe, 1867 |
Genus: |
Fregata
Lacépčde, 1799 |
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Species |
Fregata magnificens
Fregata aquila
Fregata andrewsi
Fregata minor
Fregata ariel
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There are five
species in the family Fregatidae, the
frigatebirds. They are very closely related, and are all
in the single
genus Fregata. Frigatebirds attack other
sea birds, hence the name. They are also sometimes called
Man of War birds or Pirate birds. Since they are related to
the pelicans, the term "frigate pelican" is also a name
applied to them.
Frigatebirds are large, with iridescent black feathers
(the females have a white underbelly), with long wings (male
wingspan can reach 2.3 metres) and deeply-forked tails. The
males have inflatable red-coloured throat pouches, which
they inflate to attract females during the mating season.
Frigatebirds are found over tropical oceans and ride warm
updrafts. Therefore, they can often be spotted riding
weather fronts and can signal changing weather patterns.
These birds do not swim and cannot walk well, and cannot
take off from a flat surface. Having the largest wingspan to
body weight ratio of any bird, they are essentially aerial,
able to stay aloft for more than a week, landing only to
roost or breed on trees or cliffs.
They lay one or two white eggs. Both parents take turns
feeding for the first three months but then only by the
mother for another eight months. It takes so long to rear a
chick that frigatebirds cannot breed every year. It is
typical to see juveniles as big as their parents waiting to
be fed. When they sit waiting for endless hours in the hot
sun, they assume an energy-efficient posture in which their
head hangs down, and they sit so still that they seem dead.
But when the parent returns, they will wake up, bob their
head, and scream until the parent opens its mouth. The
starving juvenile plunges its head down the parent's throat
and feeds at last.
As members of
pelecaniformes, frigatebirds have the key characteristics of
all four toes being connected by the web, a gular sac (also
called gular skin), and a furcula that is fused to the breastbone. Although there
is definitely a web on the frigatebird foot, the webbing is
reduced and part of each toe is free. Frigatebirds produce
very little oil and therefore do not land in the ocean. The
gular sac is used as part of a courtship display and is,
perhaps, the most striking frigatebird feature.
Frigatebirds obtain most of their food by
snatching it from the ocean surface. In this
case an immature Great Frigatebird is snatching
a Sooty Tern chick dropped by another
frigatebird
Their feeding habits are
pelagic. Frigatebirds often rob other seabirds of their
catch, using their speed and manoeuvrability to outrun their
victims. However, they are perfectly capable of catching
fish, baby turtles and similar prey, snatching them up from
flight.
Distribution and identifying characteristics differ among
frigatebird species, and thus are addressed in
species-specific articles.
Species
- Genus Fregata
- Magnificent Frigatebird or Man O'War, Fregata
magnificens.
Ascension Frigatebird, Fregata aquila.
Christmas Island Frigatebird, Fregata andrewsi.
Great Frigatebird, Fregata minor.
Lesser Frigatebird, Fregata ariel.
External links