#ThreatenedSpecies of the Week: Thalassarche melanophris (Black-browed Albatross)

Image source: Birds in Backyards www.birdsinbackyards.net

Thalassarche melanophris (Black-browed Albatross) is listed as Vulnerable under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act).

The Black-browed Albatross is a medium-sized albatross, which has a length of 80-95 cm, a wingspan of 210-250 cm and a weight of 3-5 kg. The species has a white head and neck, a bright yellow-orange bill and a dark brown iris. It is characterised by a black eyebrow, which gives it a frowning look (Marchant and Higgins 1990). The upperwings and saddle are dark grey and the underwing is mostly white with broad, irregular black margins. The rump and underparts are white in colour and the tail is grey, becoming darker with age.

Males and females are alike and there are no seasonal changes in the species’ appearance. However, juveniles differ in appearance from adults in a number of ways. Juveniles have a slightly paler and narrower eyebrow than adults and a pronounced grey-brown collar on the neck. In addition, the juvenile underwing is dark grey, with a diffuse greyish-white stripe down the centre of the inner wing, and the bill is dark olive-brown with a black tip.

Black-browed Albatrosses are long-lived birds, living 30 years or more. They start breeding when they are 6-13 years old and have an estimated generation length of 21.5 years. Black-browed Albatrosses breed in colonies, laying a single egg each year. They generally have the same breeding partner each season and have a strong bond to their colony of birth. The timing of breeding varies with location, but generally the breeding season extends from September to April each year.

Black-browed Albatrosses are found over Antarctic, subantarctic and sub-tropical waters. In the summer, they breed on a number of subantarctic and Antarctic islands. Nests are established on tussock-covered ledges and terraces of cliffs, slopes and hills overlooking seas or valleys. During the breeding season, they forage around the breeding island and on adjacent submarine banks. Over winter, Black-browed Albatrosses migrate northwards to forage, around continental shelf waters off Australia New Zealand, South Africa and South America. They forage in the coastal waters of continents, over up-wellings or boundaries of currents and are often found sheltering in harbours, bays or channels. The species is usually associated with mixed flocks of other seabirds, including other albatrosses and giant petrels.

Black-browed Albatrosses fly fairly low and take food from the sea surface or just below. They eat mostly krill and fish, with some salps, jellyfish and cephalopods. Black-browed Albatrosses are also enthusiastic scavengers. The species will also accompany fishing boats, where birds scavenge offal, waste and bait.

 

Information Source: Government of Australia, Department of Environment and Department of Parks and Wildlife Western Australia

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