#ThreatenedSpecies of the Week: Thalassarche cauta cauta — Shy Albatross

Photo Source: Atlas of Living Australia.
Photo Source: Atlas of Living Australia.

The Shy Albatross is listed as Vulnerable under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) and as Specially Protected Fauna under the Wildlife Conservation Act 1950.

Although numbers of Shy Albatross have been increasing through the 20th century, the species is still vulnerable to deaths associated with commercial fishing. Trawl fisheries throughout the species range also pose a threat to Shy Albatrosses, which drown if they get trapped in the nets or trawl gear or are killed by collisions with cables. Commercial overexploitation of squid or fish reserves in Bass Strait could pose a threat to Shy Albatrosses in the future by direct competition for food.

The Shy Albatross is the largest of the black-backed albatrosses, with a wingspan of 2.12 – 2.56 m. They have a distinctive underwing pattern; mostly white, with very narrow black margins and a diagnostic black notch at the top of the wing, just next to the body. The forehead and crown are white, forming a pronounced white cap sharply bordered by a narrow greyish-black brow and light greywash across the sides of the head (including nape, ear-coverts, cheeks and sides of throat in most individuals). The lower mantle and back are blackish with a pronounced silvery bloom that contrasts with the darker, uniform blackish scapulars and upperwings. The rump and upper tail-coverts are white, while the tail is a light grey, turning darker brown with wear. The bill is a uniform greyish-horn colour, merging to straw-yellow by the mid-section, with a yellow tip. The iris is dark brown, and the legs and feet are bluish-flesh.

Shy Albatrosses appear to occur over all Australian coastal waters below 25° S. It is most commonly observed over the shelf waters around Tasmania and southeastern Australia. It appears to be less pelagic than many other albatrosses, ranging well inshore over the continental shelf, even entering bays and harbours .

Most adult Shy Albatrosses remain in the waters off southeast Australia all year round, and seldom venture more than 600km from the breeding colony. Breeding occurs on Albatross Island, Bass Strait, and Mewstone and Pedra Branca, off southern Tasmania. However, juvenile, immature and some Shy Albatrosses cover much greater distances. These birds can be found in most sub-Antarctic to subtropical waters. They may also enter the tropics off South America, and have even been recorded in the Northern Hemisphere; west USA and north Red Sea.

The Shy Albatross nests on level or gently sloping ledges, summits, slopes and caves of rocky islets and stacks, usually in broken terrain with little soil and vegetation. Shy Albatrosses have an annual breeding cycle lasting about eight months, from September until April. The birds breed in colonies of six to 500 nests, usually in association with the Australasian Gannet Sula serrator. Mean nest densities are 1-2 nests per m², with some nests being only 30cm apart.

The nest is a conical mound of mud, guano, rock fragments, feathers, plant material, fish and bird bones, lined with fine material. The nest structure varies from a solid column on flat sites to a small lip on sloping rocks. The nests are re-used annually and layers of dead chicks from previous seasons are sometimes visible.  Most eggs are laid in September or early October. Breeding is asynchronous among colonies, with the mean egg-laying date at Pedra Branca (and probably the Mewstone) being about one to two weeks later than on Albatross Island. The egg is incubated for about ten weeks. The chick hatches in December and is brooded for a further three weeks. The incubation of a single egg is carried out by both sexes in alternate shifts, with a single shift averaging four days.

The main foods of the Shy Albatross are fish, cephalopods (squid), crustaceans and tunicates.

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

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