These birds (Diomedea exulans) vie with condors as the largest flying birds in the world. For most of the year they glide in solitude over the vast southern oceans, covering up to 480km a day, and staying aloft on thin, low-drag wings that lock into position to save energy. They need the wind to allow them to take off and, once airborne, can glide for hours at speeds of up to 70kph, resting only occasionally at night. In the breeding season they come together on sub-Antarctic islands, perform their bobbing, groaning courtship display and build perfectly round nests of mud on the high, windswept cliffs.
These open ocean hunters feed mainly on squid and carrion. They sometimes pluck prey from the water while in flight. Sadly, they also plunge-dive to take the bait on longline fishing tackle, particularly the sort used to catch tuna, and get snagged on the hooks and drowned. Many thousands die in this way each year.