As you'd imagine, the relaxed and pretty chilled out boat atmosphere changed straight away and I for one was shouting out the usual offensive expletives as I straight away locked onto it. It surfed the slick for a good few minutes, probably 10 or so in total on and off, and the 1st-summer Long-tailed Skua that was present had to step over to the sideshow of course.
The last shot shows the upperparts warm brown, despite the harsh light. This individual hasn't got the most complete breast band for a BBSP, but from the extensive area of dark on the lower belly it obviously extends up towards the dark chest demarcation, culminating before it with perhaps a hint of dark feathers extending towards the breast. Interestingly Flood and Fisher state that populations on some New Zealand sub-Antarctic islands show broken/incomplete belly lines and some birds show an absence of the mid belly line too. Some nice reading here and some pics on variation here. Also, foot projection in the first link states that White-bellieds show no or little foot projection while Black-bellieds show an obvious foot projection beyond the tail. However, this seems to be conflicting with what Steve Howell notes in Dutch Birding, and says essentially there is a lot of overlap in tail projection so this isn't necessarily a useful feature.
This is the fourth fregatta in the WP, and the third Black-bellied SP following previous records from Madeira in August 2011 and Lanzarote in September 2011 (as well as the Severn Beach fregatta in November 2009). So I imagine this won't be the last given the recent upsurge.
You also get nice views of other petrels too: -
|White-faced Storm-petrel - pretty much guaranteed at the Banco de la Concepcion|
|Wilson's Storm-petrel - nice fresh birds seen with newly moulted primaries|
|Madeiran Storm-petrel - the commonest storm-petrel of the trip. This is an adult warm season breeder due to the worn primaries that will be replaced shortly. Many birds were in active primary moult as you'd expect.|
|Bulwer's Petrel - common, though not too bothered about coming into chum slicks and generally seen just cruising about the boat|