Tristan albatross

Source: Wikipedia, the free encyclopedia.

Tristan albatross

Critically Endangered  (IUCN 3.1)[1]
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Procellariiformes
Family: Diomedeidae
Genus: Diomedea
Species:
D. dabbenena
Binomial name
Diomedea dabbenena
Synonyms

Diomedea exulans dabbenena Mathews, 1929[2]

The Tristan albatross (Diomedea dabbenena) is a large seabird from the albatross family. One of the great albatrosses of the genus Diomedea, it was only widely recognised as a full species in 1998.[3]

Taxonomy

Albatrosses belong to the family

triglycerides that is stored in the proventriculus. This is used against predators as well as an energy rich food source for chicks and for the adults during their long flights.[4]

While not all scientists believe it is a full species with some retaining it as a

species complex[5] supported the split. Other studies have shown it to be the most genetically distinct member of the wandering albatross species complex.[6] This may be due to it diverging from their common ancestor before all its relatives, or because it underwent particularly strong genetic drift. Among the major experts, BirdLife International has split this species,[7]

Etymology

Diomedea refers to

epitheton dabbenena refers to Roberto Dabbene
, Italian-Argentine ornithologist.

Description

The Tristan albatross is practically indistinguishable from the snowy albatross at sea but is smaller and has a slightly darker back. It is 110 cm (43 in) from beak to tail[9] and has a wingspan of up to 3.05 m (10.0 ft).[10] The Tristan albatross also never attains the full white plumage of the snowy albatross, and its bill is about 25 mm (0.98 in) shorter.[7]

Distribution and habitat

Due to the difficulty in distinguishing them from snowy albatrosses, their distribution at sea is still not fully known, but the use of satellite tracking has shown that they forage widely in the South

Atlantic, with males foraging west of the breeding islands towards South America and females to the east towards Africa. There have been sightings near Brazil and also off the coast of Australia.[7]

Tristan albatrosses are

endemic to the islands of the Tristan da Cunha group and more specifically Gough Island. The majority of the world's population nest on Gough Island, around 1500 pairs. On some years a pair breeds on Inaccessible Island
.

Behavior

The Tristan albatross feeds on fish and

cephalopods
.

They breed biennially and will nest in wet heath from 400 to 700 m (1,300–2,300 ft) in elevation.

monogamous, and do not start breeding until they are about 10 years old.[4]

Conservation

They were formerly threatened by

long-line fishing and these mice. Recent counts suggest that the population on Gough has decreased by 28% over 46 years, whereas population modelling predicts annual decline rates of 2.9–5.3%. More recent modelling, conducted over three generations since 1980, suggests a decline equivalent to a >96% reduction in population size over three generations, since declines began. The rate of decline is therefore placed here in the band of 80–100% over three generations (86 years).[7]

Formerly classified as an

IUCN,[12] it was suspected to be more threatened than generally assumed and undergoing a marked decline. Following the evaluation of its status, this was found to be correct, and the Tristan albatross was consequently uplisted to Critically Endangered status in 2008.[1] They have an occurrence range of 14,000,000 km2 (5,400,000 sq mi) and a breeding range of 80 km2 (31 sq mi).[7]

References

  1. ^ . Retrieved 19 November 2021.
  2. ^ a b BirdLife International (2008b)
  3. ^ Robertson, C. J. R. & Nunn, G. B. (1998)
  4. ^ a b Double, M. C. (2003)
  5. ^ Burg & Croxall (2004)
  6. ^ Brooke, M. (2004)
  7. ^ a b c d e f BirdLife International (2008a)
  8. ^ Gotch, A. F. (1995)
  9. ^ "Tristan albatross - Diomedea dabbenena: Species Information - ARKive". Archived from the original on 2008-09-05. Retrieved 2008-09-19.?
  10. ^ "Diomedea dabbenena — Tristan Albatross". Species Profile and Threats Database. Australian Government - Department of Climate Change, Energy, the Environment and Water. Retrieved 10 October 2023.
  11. ^ Wanless, R. M. et al., (7 June 2007)
  12. ^ Lee, J. (2008)

Sources

External links