Bannerman's Shearwater

Bannerman's Shearwater (Puffinus bannermani) is a small black-and-white shearwater with dark upperparts, white underparts and a compact, narrow-winged silhouette. Body shape, bill structure, plumage pattern and voice provide the strongest field characters. Age, sex and season may alter its appearance, so identification should combine several features and careful direct field comparisons with similar species in the same habitat (Wikipedia, general species account).

It is associated with the Ogasawara Islands and nearby seas, where it takes small marine prey and uses rocky ground and cavities for nesting; much of its ecology remains poorly documented. Its movements and social behaviour vary through the year, with breeding birds generally more dispersed and non-breeding birds gathering where food is concentrated. Japanese records place it within the country's documented avifauna as a resident, migrant or visitor (Wikipedia, general species account; Wildlife of Japan occurrence records).