Grey Nightjar

Grey Nightjar (Caprimulgus jotaka) is an East Asian nightjar patterned grey, brown and black, with white wing and tail marks most evident in males. 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 feeds nocturnally on moths, beetles and other flying insects in forest clearings and early-successional habitats. 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).