This stunningly colored bird goes by the rather dull name of the Purple Swamphen (Porphyrio porphyrio).
I spotted a group of six while taking a side track home (which passes through Gould’s Lagoon).
For you birders, the Swamphen and it’s less brightly plumed cousin the Tasmanian Native Hen, are Gallinules, which are members of the Rail family.