The Waved albatross (Phoebastria irrorata), also
known as Galapagos albatross, is the only member of the family Diomedeidae
located in the tropics. When they forage, they follow a straight path to a
single site off the coast of Peru, about 1,000 km (620 mi) to the east. During
the non-breeding season, these birds reside primarily on the Ecuadorian and
Peruvian coasts.
Geographic Range
Waved
albatrosses spend their time in the ocean between the west coasts of Peru and
Ecuador and the Galapagos Islands. They come to the small island of Isla
Espanola in the Galapagos to breed along the south/southeast coast. There have
been reports of waved albatrosses breeding at Isla de la Plata, an island about
20 kilometers off the coast of Ecuador, but these sightings are rare. The waved
albatross has been spotted in Panama and Columbia, however they are rarely seen
north of the equator. The breeding range has changed in the past few decades.
Two inland breeding colonies on Isla Espanola disappeared between 1971 and
1994. The central breeding colony is located in the middle of the south coast
and projects inward towards the center of the island. The majority of breeding
occurs along the southern coasts which includes the far west Punta Suarez, as
far south as South Point, and as far northeast as Punta Cevallos, with small
isolated colonies inland west from Punta Cevallos.
Waved
albatrosses are pelagic birds, spending their lives in the open ocean between
the western coasts of Ecuador and Peru and the Galapagos Islands. When
breeding, they nest in areas with limited plant life on hardened lava pools
surrounded by boulders on a single island, Isla Espanola. More recently, they
have been spotted nesting in thick brushwood, grasses, and shrubbery as the
habitat has changed due to the eradication of invasive feral goats (Capra
hircus). Breeding colonies are found from just above sea level to 215 meters.
Physical Description
These
birds are light to dark brown in color on the abdomen with grey in transition
spots as it changes to solid white at the head and neck. Their feet and legs
are a blue tint, their eyes are dark brown, and they have a mustard yellow
bill. Juvenile birds are similar to adults in color except that the head is
more white than yellow/grey. Immature chicks are covered in a uniform brown
plumage with a dark brown bill. The adults stand just shy of a meter in height
(80 to 90 cm). The waved part of its name comes from the wave like pattern on
the feathers of adult birds near the nape of the neck as the color transitions
to brown. They weigh approximately 2.5 to 4 kilograms with males being
considerably heavier than females. Because of their large size, they are clumsy
on land and flying is possible but difficult. They need a running start and
rely heavily on winds to launch them into the air. Once in the air, they have
been described as being extremely graceful. They have a wingspan between 220
and 250 cm in length with males being larger than females.
Waved
albatrosses are monogamous, mating for life. Male waved albatrosses arrive at
Isla Espanola around late March and wait for their mates. Their courtship
ritual is loud and boisterous. They face each other and do a series of honks,
bows, and beak touching and chattering. Every few minutes, they circle each
other and continue the dance. The dance may last several minutes. Newly coupled
birds and established couples that had failed reproduction in the last season
dance longer. After mating, the female lays a single egg. Waved albatrosses are
cooperative breeders. They temporarily help others raise chicks or incubate
eggs while biological parents are away.
This
species is classified as Critically Endangered because it has an
extremely small breeding range, essentially confined to one island, and
evidence suggests that it has experienced a substantial recent population
linked to bycatch mortality in artisanal fisheries in its principal foraging
grounds.
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