Thanks Brendan
To be honest, it looked nothing like the bird in your video. Your bird is feeding - mine was trying to fly as fast as possible, in fact it was shearing over the waves like a shearwater.
I only saw it very briefly through binoculars, the rest of the time I was trying to get good photos because I realised immediately it was something unusual. Through binoculars it looked like a small all-dark shearwater or petrel. Afterwards, I could only look at the photos in the camera viewfinder as I don't have a computer on Po Toi at present, and what I could see was too small to really identify it. I realised the shape was wrong for a shearwater or Bulwer's Petrel and I thought some of the photos looked like those of the Brown Noddy in 2006. It was only when I got home today I could really see the photos and see what the bird was.