The characteristic features of albatrosses’ life history include delayed age of maturity and low reproductive rate. Albatrosses are long-lived seabirds. The oldest known was a female northern royal albatross that was over 60 years old when she ceased returning to her nest at Taiaroa Head. The smaller albatrosses, or mollymawks, also have long lives, with a female Buller’s albatross breeding at the Snares Islands when over 50 years old.
Breeding
Most albatrosses breed in colonies on remote islands free from mammalian predators. Some build substantial nests that are used for many seasons, and pairs often remain together for many years. An unusual feature of the breeding system is that the great albatrosses (wanderers and royals), the grey-headed albatross and the two sooty albatrosses breed every two years, but the others usually breed every year. For the great albatrosses at least, biennial breeding is related to the fact that these birds take too long from egg-laying to fledging to breed every year.
Breaking eggs
A northern royal albatross egg weighs half a kilogram, and is incubated for 79 days. From when the chick makes the first hole in the shell, it can take several days to hatch completely.
Hatching
At each breeding, a single white egg is laid and both parents share in its incubation, which takes 60 to 79 days, depending on the species. Once the egg hatches the chick is brooded or guarded by a parent while the other gathers food for it. After about 21 days, or longer for larger species, the chick is capable of defending itself at the nest and can maintain its body temperature, which means that both parents are free to go to sea to gather food. The parents feed the chick by regurgitating the food directly into its open beak, which is placed crosswise as a funnel inside the beak of the parent.
Fledging
When hatched, the chicks are covered in loose down. As they grow, this is replaced by feathers, and they are fully feathered before they make their first flight. Once they fly, fledglings must learn to feed and fend for themselves without any parental assistance. Chicks fledge at four to five months for mollymawks, and eight or nine months for great albatrosses. Once they make their first flight, fledgling albatrosses disperse widely over the sea and may remain continuously at sea for several years. Subsequently, most return to their original colony to prospect for a nest site and to find a partner. This process may take several years, and so some albatrosses do not begin breeding until they are over 10 years old.