A bird census in the Imperial Palace for 1971

Abstract

This is the 7th annual report of monthly (except August for this year) census in the Imperial Palace from April, 1971 to March, 1972. The same route of 4.1km. was censused usually from 9.40 to 11.30 a.m. The results are tallied by two areas, one including moats of winter duck resort (chiefly Anas poecilorhyncha and Aix gelericulata) and heron (egrets) colony. The monthly species records in total area ranged 20-29 (av. 23.4) and the number of individuals 256-609 (av. 383.2). Only two species, Acrocephalus arundinaceus and Bubulcus ibis were added to the list, making a total of 49 species for 1971 and 81 species so far recorded. General avifauna was rather stable annually but egrets and ducks are decreasing, perhaps reflecting the effect of pesticides used in the field (dead egrets were found in the area), and the heron colony is attacked by Corvus macrorhynchos. Tables of feeding observation, dead birds, flock components of Parus major and Phasianus versicolor are presented.