Bird-Watching

... er, bird-watching at a very basic level.

In the Grand Tradition of beachcombing, L and I have been roaming over a variety of wide southern beaches, picking up dead stuff and making it into Art. yes, really. We found a really cool bird skull on the beach near Waiwera. Other photos here. The battery (for scale) is an AAA. When we found it, that crest still had a pinkish tinge of blood within: but the skull itself had been picked very clean. Any ideas as to what species (or even genus) of bird this might once have been part of?