Fluttering Shearwater

A medium to small-sized shearwater with dark-brown-and-white colour in body. The upper parts, including neck, wings and tail are uniformly dark brown. Grey-brown colour in face and neck gradually fading into white below the eye. Under body, from chin to the under-tail, is white except for a dark thigh patch that can be seen in flight. Bottom wing commonly white while axillary area is covered in grey-brown fur. Under light conditions, the appearance can changed. Fluttering shearwater has pinkish-brown legs and feet with bark webs, feet extend beyond the tail in flight. The bill is long and thin with dark colour. The tail is fan-shaped and short in flight and it has mixed colour －dark brown and white. Moult start from late January and the dark upper surfaces fade to mid-brown quickly. The colour of birds near the stage of moult (February to April) is pale rusty brown and they appear ragged at this stage. Their voice is unusual and disjointed: ka-hek-ka-hek-ka-hek and usually made in flight. It has also been noted that their flight pattern is somewhat determined, low and fast. Rapid spurts of wing-beating interspersed by gliding. The average body mass of females is 302g while males is 243g. Their eggs are pure white and oval. The young birds have the same colour as adult from the nest, but with lighter color in the margin of wing-coverts. Nestlings have very thick slate-coloured soft feathers on the upper and white down on the under.