An interesting photo of this bird's plumage. It isn't a cormorant it is an Australasian Darter Anhinga novaehollandiae, sometimes referred to as a snake bird because of their long neck. I've looked down from a breakwall on these birds feeding and they do use their wings to manouvre /fly underwater. I remember reading something about their feathers not being oiled like some waterbirds, hence the need for regular dry outs.
