Laysan Albatross

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Image:Laysan albatross.JPG

Common Name: Laysan Albatross
Scientific Name: Phoebastria immutabilis

Size: 32 inches (81 cm); 195–203 cm wingspan

Habitat: Pacific Ocean; wide range across the North Pacific. Its main breeding colonies are in the Hawaiian Islands, particularly the islands of Midway and Laysan. It also nests in the Bonin Islands near Japan, the French Frigate Shoals, and has begun to colonize islands off Mexico, such as Guadalupe Island and others in the Revillagigedo Archipelago.

When away from the breeding areas they range widely from Japan to the Bering Sea and south to 15°N.

Status: Near Threatened. Global Population: 1,180,000 mature individuals. Historically, populations were greatly reduced by feather and egg collecting in the late 1800s and early 1900s, and by high seas drift nets used for squid and salmon that were active between 1978 and 1992. Prior to its closure, the high seas driftnet fishery killed over 17,500 Laysan Albatrosses in 1990 alone. Current key threats are being caught as bycatch in pelagic and demersal longline fisheries in the North Pacific as well as in illegal high seas driftnet operations.

Analyses in 2001 estimated that pelagic longliners in the North Pacific may kill 5,000-18,000 Laysan Albatross per year, with 8,000 thought the most likely figure, while demersal longline operations in the Bering Sea and Gulf of Alaska groundfish fisheries were estimated to kill 715 birds per year. However, more recent estimates indicate a drastic reduction in bycatch from previous years (with an estimated 83 birds taken in 2005). This is very likely attributable to the use of effective seabird avoidance measures. The bycatch rates in Japanese and Taiwanese pelagic longline fisheries in the North Pacific are still largely unknown.

Other threats include organochlorine contamination, invasive species, plastic ingestion, lead poisoning, human disturbance and conflicts with aircraft. Up to 10,000 chicks per year are potentially affected by lead poisoning from paint on buildings at Midway Atoll. Avian pox virus affects chicks on Midway and the Main Hawaiian Islands where introduced mosquitoes are present, but studies on O'ahu colonies show that fledging success was not reduced. Dogs kill adults and chicks on inhabited islands in Hawaii. Verbesina encelioides is an aggressive weed that degrades nesting habitat in the Northwestern Hawaiian Islands and introduced predators (notably the Polynesian Rat Rattus exulans) are an issue for colonies in Mexico and on the Main Hawaiian Islands.

Conservation measures underway… All of the major Hawaiian breeding localities are part of the US National Wildlife Refuge system or State of Hawaii Seabird Sanctuaries and, in 2006, the Papahânaumokuâkea Marine National Monument was established, encompassing all of the Northwestern Hawaiian Islands. Three breeding sites, supporting over 90% of the breeding population, are either counted directly or sampled at regular intervals. In 1991, a 50 Nautical Mile Protected Species Zone was established around the Northwestern Hawaiian Islands (primarily to protect monk seals). No longline fishing is allowed in this zone. Awareness programs and mitigation trials have been started in several major longline fleets operating within the foraging range of this species. The Hawaiian longline fishing fleet is required to use measures to reduce bycatch of seabirds. In 2006, the Western and Central Pacific Fisheries Commission adopted a measure to require large longline vessels to use at least two seabird bycatch mitigation measures when fishing north of 23 degrees North. Predator control programs are conducted at colonies in Mexico and the Main Hawaiian Islands.

Diet: Squid, but it also eats crustaceans, fish eggs and fish. It is a surface feeder. It scoops up its prey from just under the surface of the water. It does most of its feeding at night.

Breeding: Small two-tone, gull-like albatross. Upper wings, mantle, back, upper rump and tail blackish-grey. Head, lower rump and under parts white. Blackish smudge around eye. Bill pinkish with darker tip. Black-and-white under wing pattern varies between individuals having narrow black margins and variable amounts of black in the underwing coverts. Juveniles are very similar but have a greyer bill and wholly dark upper rump.

The Laysan Albatross is colonial, nesting on scattered small islands and atolls, often in huge numbers. It builds different styles of nests depending on the surroundings, these range from simple scoops in the sand to nests using vegetation. Laysan Albatrosses have a protracted breeding cycle, and breed annually, although some birds skip years. Juvenile birds return to the colony three years after fledging, but do not mate for the first time until seven or eight years old. During these four or five years they form pair bonds with a mate that they will keep for life. Courtship entails especially elaborate 'dances' that have up to 25 ritualized movements. Occasionally the birds form homosexual pairs consisting of two females. This has been observed in the colony on the Hawaiian island Oahu, where the sex-ratio of male to female is 2 to 3. Unpaired females pair up among themselves and successfully breed. Eggs are often fathered by paired males, who "cheat" on their spouse.

The single egg is buff-white, and it may have spots. Both birds incubate the egg; the male does so first. Incubation takes about 65 days, and is followed by several weeks of brooding, after which both parents are out at sea to provide for the growing chick. The chick takes about 160 days to fledge. This time investment by the parents may explain the long courtship; both parents want to be sure the other is serious. The chicks are fed a stomach oil which is regurgitated by the parents.

Cool Facts: The Laysan Albatross is normally a silent bird, but on occasion they may be observed emitting long "moo"-ing sounds, descending whinnies, or rattles. Female Laysan albatrosses bond for life, so they can cooperatively raise their young.

A female Laysan Albatross known as "Wisdom" is the oldest known wild bird in the United States or the Northern Hemisphere. "Wisdom" was banded by a U.S. Geological Survey researcher in 1956 and in March 2011 was seen rearing a new chick on Midway Atoll. As of 2011 "Wisdom" is estimated to be at least 60 years old.


Found in Songbird ReMix Seabirds Volume 2

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