introdUction to the world’s seabirds | 9beach, especially when showing off their brightly- coloured feet of which
they seem unreasonably proud. Gannets and boobies commonly plunge
from a height into the sea to feed.
The three tropicbird species are all birds which plunge to catch their
prey. They are exclusively (and predictably) tropical and have mainly
white plumage, adorned by a pair of spectacularly-long central tail
feathers, white in two species and red in the third.
Also tropical are the five frigatebird species which are predominantly
black. By way of sexual ornamentation, mature males have red throat
pouches that can be inflated to attract females. Since their legs are tiny,
frigatebirds are virtually unable to walk, but the reduced undercarriage
and the large angular wings mean that their wing loading, the weight of
bird supported by each square centimetre of wing surface, is the lowest
of all birds. This gives them extreme agility, well displayed when they
are chasing other seabirds, forcing them to regurgitate, and then catch-
ing the vomited spoils in mid- air before they splat into the sea.
There are about 35 species of cormorant or shag. Because various dif-
ferent species with vernacular names of cormorant and shag are placed
The bare- skinned red throat of a male Magnificent
Frigatebird is inflated to attract a mate.