Although Australian in origin, the Crested Grebe has established itself at home in the South Island of New Zealand. A cosmopolitan species has close cousins in Africa and the Palaearctic, as well as Australia of course. It can be found in many of the clear, shallow subapline lakes east of the Southern Alps, and also in Westland. During a particularly cold winter, when these lakes freeze over, the grebes take flight and migrate closer to the coast.
The species are almost entirely aquatic, and rarely, if ever, come onto dry land (although they do occasionally scramble onto mud banks, as seen here). Indeed, although they are strong fliers, they are rarely seen in flight and it is thought that they move between lakes at night. To take to the air, they require water for lift off, and take off much like swans - with a running start. Their feet are positioned very far back, almost under their tail, which makes walking difficult and also means that if they misinterpret their landing spot and land in a shallow puddle instead of on the lake, they will fall on their face. The latin name Podiceps is derived from podex meaning "rump" and pedis meaning "Foot" - so literally = "rump foot". These feet however make them swift swimmers and expert divers. They make deep dives in pursuit of live prey - crustaceans, insect larvae and fish and can stay down for several seconds - the longest recorded dive was 53 seconds.
Courtship involves an elaborate dance, and is most beautiful to behold. In early spring the pairs begin to form and the male performs for the female, splaying his neck ruff and arching his head crest. Then both birds rise in the water, facing each other and shake their heads, crests erect, whilst uttering low, moaning cries. It is a beautiful, syncronised ballet, and I hope one day to witness it.
Nests are built of sticks, rushes and waterweed, collected together to form a large, untidy island of a mound. Usually this is anchored to some sort of plant formation at the verge of the lake. The hen lays up to six eggs over a period of as many days and incubation starts immediately. Chicks therefore hatch at intervals, and sometimes older siblings will take off with one parent whilst the other hatches out the remaining eggs. Chicks ride on their parents back, usually in pairs until they become too big to do so. Some still make an attempt, however.
Never particularly populous, one pair of grebes tends to inhabit one lake, and thus they are quite difficult to see in the wild. One lake on the West Coast, Ianthe, is reported to hold higher numbers of these regal birds, and I recently visited there and was lucky enough (on the return visit) to find a single Crested Grebe, cruising the lake. I believe I may also have observed them at Lake Alexandrina in my youth, but as an avid birdwatcher, do wonder now if that was just fanciful, wishful thinking as I never saw them close-up. The grainy photo taken at maximum zoom is without any shade of a doubt, however, a Crested Grebe:
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