Abstract
Dryocopus m. martius occurs all over Hokkaido, but little has been known of its nest. Nest was found at Moeribetsu near Teshikaga town, May 18, 1950. Young had already hatched. The nest was 10 meters from the ground in a dead tree, Ulmus Davidiana planch. It was in a hollow 70cm deep, the nest entrance was 12cm in diameter and the inside diameter of the nest chamber was 27cm. They were four, one male, and three females. Upon fledging the female measurements were as follow: wing 180mm to 210mm, bill 43 to 50, tail 50 to 95.
