Black Woodpacker feces were collected, for analysis, from winter to spring in the Tomakomai Experiment Forest of Hokkaido University.
(1) Eight animal and one plant species of prey were identified.
(2) The most important food item for both sexes was the carpenter ant Camponotus obscripes during winter (it occupied 80-100% of total numbers of prey). Black woodpeckers foraged on ants at the lower or basal parts of trees. Other ant species and coleoptera were also taken but were of less importance.
(3) The food preferences changed from winter to spring, with many small ants Lasius niger being taken from early spring onwards.