Lesser Frigatebird

The lesser frigatebird, Fregata ariel, is the most diminutive member of the frigatebird family, with an average length of about 75 cm. It is a seabird with a slender build and predominantly brownish-black plumage. Its wings are long and narrow, and it sports a deeply forked tail, characteristic of its kind.

Identification Tips

Males can be identified by their striking red gular sac, which they inflate during courtship displays. They are mostly black with a white patch on the flank that extends onto the underwing as a spur, and a pale bar on the upper wing. Females are slightly larger, with a white breast and belly, and a black head and neck with a white collar. They also have a narrow red ring around the eye. Juveniles and immature birds have white spurs in their armpits, aiding in their identification.

Habitat

Lesser frigatebirds are pelagic, spending most of their life over tropical and subtropical waters. They are rarely seen on land except during breeding seasons when they nest in trees or on the ground on remote islands.

Distribution

This species is widespread across the Indian and Pacific Oceans and can also be found off the Atlantic coast of Brazil. They are known to breed on remote islands, including Christmas Island, and are often seen from the mainland before tropical cyclones.

Behaviour

These birds are masters of the air, with a light skeleton and long wings adapted for soaring. They rarely swim and are not adept at walking but can climb in vegetation. They are known for kleptoparasitism, harassing other birds for food, although this behavior is not their primary means of feeding.

Song & Calls

The courtship display of the lesser frigatebird includes a variety of calls, bill rattling, and wing spreading, particularly by males to attract mates.

Breeding

Breeding occurs from May to December in the Australian region. They nest in trees, with both sexes contributing to nest building, incubation, and feeding of the young. A single egg is laid, hatching after 6-7 weeks, with fledglings remaining in the nest for about 6 months.

Similar Species

The lesser frigatebird can be confused with other frigatebird species, but it is distinguishable by its smaller size and specific plumage characteristics, as described in the identification tips.

Diet and Feeding

Their diet mainly consists of fish and squid, which they skillfully snatch from the ocean's surface. They are also known to feed on flying fish.

Conservation Status

The lesser frigatebird is classified as Least Concern by the IUCN, with a large global population and extended range. However, certain subspecies, such as the F. a. trinitatis, are critically endangered and have a very restricted breeding range. Conservation efforts have been successful in some areas, with the removal of invasive species leading to the reestablishment of colonies.