Christmas Shearwater

The Christmas shearwater is a slender-bodied shearwater, about 36 cm long, with a wingspan of around 75 cm, and weighs around 350 g. It has dark plumage all over, generally blackish-grey with a rusty-brown tinge, slightly paler on the underside of the bird, and with some small edging of white under the chin and pale fringes to the upperwing coverts. It has brown-grey feet and a dark bill and eyes. Both sexes are alike, as are the young after fledging. Nestlings are covered in dark grey down feathers. The species closely resembles the sooty (Puffinus griseus) and short-tailed shearwaters (P. tenuirostris), but has dark brown underwings and is smaller. The short tail of the Christmas shearwater does not appear blunt except when spread, but in flight usually tapers to a point, enhanced by the feet which protrude beyond the tail-tip. It often flies in a leisurely way like the related Procellariidae, and thus can be mistaken for a petrel. In particular, it can appear similar to the extremely rare Fiji petrel (Pseudobulweria macgillivrayi), a gadfly petrel-like relative of the shearwaters. The two species share a similar morphology and colouration, but the bulbous head and rather thin long bill – typical for shearwaters – distinguish P. nativitatis from the slim-headed thick-billed Fiji petrel.