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Phoebetria

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Template:Taxobox begin Template:Taxobox begin placement Template:Taxobox regnum entry Template:Taxobox phylum entry Template:Taxobox classis entry Template:Taxobox ordo entry Template:Taxobox familia entry Template:Taxobox genus entry
Reichenbach, 1853 Template:Taxobox end placement Template:Taxobox section subdivision P. fusca (Hilsenberg, 1822)
P. palpebrata (Forster, 1785) Template:Taxobox end The sooty albatrosses or sooties are small albatrosses from the genus Phoebetria. There are two species, the Dark-mantled Sooty Albatross ( or Sooty Albatross, P. fusca) and the Light-mantled Sooty Albatross (P. palpebrata). The sooties have long been considered distinct from the rest of the other albatrosses, and have retained their generic status through the many revisions of the family over the last 150 years. They have tradditionally thought of as primitive, sharing some morphological features with the other petrel families. However molecular work examining the mitochondrial DNA has show that the taxon is related to the mollymawks (genus Thalassarche), and that the two taxa are distimct from the great albatrosses and the North Pacific albatrosses.

Both of the sooties have distinctive black plumage over the head, wings and bellies. The Dark-mantled Sooty has a dark back and mantle as well, where as the Light-mantled Sooty has a ashy-grey mantle, back and rump. The two species can also be told apart by the narrow yellow line on the Dark-mantled's bill. Despite the differences between the two species they can be hard to tell apart at sea, especially in poor light. Both species have a white incomplete eye-ring, dark bills and grey feet. They are the smallest albatrosses, with wingspans of 200cm and are very narrow as well. Unique amongst the albatrosses they have long stiff wedge shaped tails, the purpose of which is unclear but seems to be related to their ability to dive for food.

The sooties, like most seabirds, are colonial, although sooties are less colonial than the other species of albatross. In fact, on some breeding islands (like Tristan da Cunha) sooties nest in very small groups or clusters of two to five nests, and the Light-mantled Sooties will even nest singly. This is in part due to the influence of humans, and in part due to their tendency to nest on cliffs, unlike the flatter ground prefered by other albatrosses. Sooties build cone shaped nests and lay a single egg. Eggs are incubated for 70 days, by both parents, the male taking the first stint after laying (lasting 11 days) therafter both parents taking it in turns of 7 days. After hatching the chick is brooded for 20 days until it is able to thermoregulate on its own, after which both parenst undertake the task of feeding it, on avarage bringing food to the chick every three days. The chick is fed for about 160 days, until it is able to fledge. There is no parental care after fledging. Sooties are able to complete a breeding cycle in under a year, but do not breed in consecuitive years, instead taking a year off and returning to breed every two years. Around 22% of Dark-mantled Sooties survive until adulthood (there are no figures for Light-mantled), both species return to the breeding colony after 7-10 years of fledging, and begin to breed a few years later.


References

  • Brooke, M. (2004). Albatrosses And Petrels Across The World: Procellariidae. Oxford University Press, Oxford, UK ISBN 0-19-850125-0
  • Tickell, W.L.N. (2000). Albatrosses Sussex:Pica press, ISBN 1-873403-94-1