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The breeding of the Chatham Albatross is restricted to 'Pyrimad Rock' in the Chatham Islands. Chatham Albatrosses build their nests on rocky ledges and steep slopes on Chatham Island. Around 1,200 to 1,500 Chatham Albatross chicks fledge every year. The breeding population of the Chatham Albatross is estmated at 3,200 to 4,200 pairs. This was taken by an aerial survey in the 1970s. The land based counts however counted 5,333 occupied nests. Because it only has one breeding and a small population, it is listed as Critically Endangered.The general population number is quite different because it has the addition of non-breeding birds, so the total population of the Chatham Albatross could be up to 18,000 to 20,000 pairs.
The Chatham Albatross reaches sexual maturity after about 5 years, which is quite slow, but even then they wait 2 to 3 years before breeding. Young albatrosses who cannot breed yet will attend a colony before beginning to breed, spending quite a few years learning and practicing the complicated breeding rituals (or 'dances') the Albatross family is famous for. This behaviour includes performances of actions such as preening, pointing, calling, bill clacking, and combinations of these actions.
When the Chatham Albatross is ready to breed it will dance with several partners, but after a few years they will dance with less and less partners until eventually a single partner is chosen and they become a breeding pair. That pair will usually last for life. The 'divorce' of a breeding pair is rare. It usually only happens after years of breeding with no success. Then they begin an individual language which, when finished, will be unique to the pair. However almost all of that dance will never be used again.
(A Chatham Albatross in flight over water.)
The Chatham Albatross only lays a single egg once every 2 years from August to April if the chick they breed is raised successfully. If the eggs or chicks that do not survive they re-nest the following season. Only 69% of fledglings survive to 5 years old.
The Chatham Albatross and other southern albatrosses create quite big nests for their egg. The nests are like a 'shallow cup' made of soil, rock chips, and vegetation.
Both Albatrosses of the breeding pair incubate the egg, taking it in turns to incubate for periods of time between 1 day and 3 weeks. It takes around 70 to 80 days for the egg to hatch. That is the longest incubation period for any bird. The process is tiring, the albatross could lose 83g of body weight a day.
Once the egg has hatched, the chick is guarded by the parents until it can defend itself, which takes about 3 weeks. Again,the parents each take turns protecting the chick. During this time period the adult Albatrosses feed the chick small portions of food. Once the brooding period is over, the chick is fed regularly by the parents.
Chatham Albatross