Tristan Albatross (Diomedea dabbenena)
Slightly smaller than Wandering Albatross, with a shorter bill. Plumage takes longer to whiten and does not attain entirely white plumage of old male Wandering Albatrosses. Therefore, birds at sea probably need to be identifiable with certainty. Typical ad. males have mostly dark upper wings with a pale patch on the elbow, but some have more extensive white upper wings; older birds seem to have less black in the tail tip relative to the extent of black in the upper wing than similar-plumaged Wandering Albatrosses, but more data is needed to confirm this trait. Most ad. females retain brown feathers on the crown, back, breast and flanks, resembling immature Wandering Albatross, but old females resemble ad. males. Juv. Like juv. Wandering Albatross.
Occasionally gives grunts and whinnies at sea, inseparable from calls of Wandering Albatross.
Status and biology
CRITICALLY ENDANGERED due to accidental mortality on fishing gear and high chick mortality due to introduced mice at the colony on Gough Island. It mainly remains in oceanic waters of s Atlantic, typically north of 35°S, but some venture across the Indian Ocean to Australia. Ringing and tracking data confirm occurrence off the west coast of s Africa, but abundance is unknown—global population <20 000 birds.
Tristan Albatross Diomedea dabbenena
Slightly smaller than the Wandering Albatross, with a shorter bill, plumage takes longer to whiten, never attaining the entirely white plumage of old male Wandering Albatrosses. Birds at sea are probably not identifiable with certainty. typical ad
males have mostly dark upper wings with pale patches on the elbow, but some have more extensive white upper wings.
Relative to Wandering Albatrosses at a similar stage, they tend to have less black in the tail tip. Most ad females retain brown feathers on the crown, back, breast and flanks, but old females resemble ad males. Voice: Similar to that of Wandering Albatross. In full display, he spreads his wings and throws his head back. Status and biology:
CRITICALLY ENDANGERED. L, 200 pairs breed annually, almost all on Gough Island; only 1 or 2 pairs breed on an Inaccessible slat in the Tristan da Cunha group yearly. It remains mainly in the South Atlantic, but some non-br birds disperse into the Indian Ocean, reaching Australia. The abundance of Southern Africa is poorly known due to the difficulty of identifying birds at sea. Breeding adults forage in a broad area from 28-489S, between 50°W and 10°E. Many non-br ads forage in oceanic waters SW of Africa, with a secondary ‘hotspot’ off n Namibia. Favours fairly warm water (15-20°C), >1,000m deep. Breeding biology is similar to the Wandering Albatross’s but suffers high chick mortality due to mouse predation at Gough Island. Eats mainly squid and carrion.
In many ways, these birds are the masters of our blue planet. They can fly enormous distances each year in search of food, with satellite tracking devices now demonstrating just how extensive their movements are. It is also noteworthy that young birds, males and females follow different routes and forage in different parts of the oceans. This unparalleled mobility is due to their incredibly long wings, with the larger species reaching wingspans of 3.5 m – the biggest of any bird.
They glide seemingly effortlessly and with minimal flapping by exploiting wind speed differences through dynamic soaring and slope soaring. This enables them to travel almost 1,000 km/ day without their heartbeat elevating greatly.
When they drift on the water, you can see how massive they are, dwarfing other seabirds except for the giant petrels. That being said, they are divided into two groups (spanning four genera): the white-backed ‘great albatrosses’ are the true giants, but the dark-backed
‘Mollymawks’ are considerably smaller. Some of the smaller species may dive underwater, but albatrosses feed primarily by seizing fish, squid, krill, and fishery discards from the surface.
They breed on remote oceanic islands where they form lifelong pair bonds (with occasional indiscretions) that are established through dancing. Sexual maturity is only reached around age five, and breeding is further postponed for several years while pair bonds are formed. Coupled with the longest incubation period of any bird and the fact that young may only fledge after 280 days, albatrosses have a disastrously slow reproductive rate.
Furthermore, pairs often take a year’s sabbatical between breeding attempts.
This means that any birds lost to accidental sea fisheries bycatch, plastic ingestion, or other threats have a major impact on their overall population, and albatrosses are the most threatened bird family worldwide. Fortunately, these threats have largely been mitigated by ongoing conservation efforts. A current priority is eradicating predatory alien mice from their breeding islands.
In support of the Mouse Free Marion project in conjunction with Birdlife South Africa and the Department of
Forestry, Fisheries and the Environment
Text care of Firefinch Bird App and Proff. Peter Ryan (Guide to Seabirds)