Well, the birds Magpie Geese (Anseranas semipalmata). The magpie comes from their black and white colour - almost anything in Australia that is black and white is called a 'Magpie' something. The Goose come from the way it looks! The semipalmata of the scientific name refers to the fact the these birds only have half webbed feet.
That feature, and a few others, mean that this species is a bit of a loner in the world of classification - there are no other birds in the genus Anseranas and in fact this is the only genus in its family as well. Which leads to the type of conclusion that I love, where the Magpie Goose is neither a Magpie nor a Goose! (And its not a big duck either!)
Anyway, this bird used to be widespread in SE Australia, but it now only really common in Northern Australia. The large knob on the head of some of these birds show that they are males.
The bird in the last image is a juvenile bird - and does not yet have the white neck of the adult.
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