A bird census in the Imperial Palace for 1973

Abstract

This is the 9th annual report of monthly census in the Imperial Palace in Tokyo from April, 1973 to March 1974. The same route of 4.1km was censused from about 9.40-11.30 a.m. as in the previous years. The results are tabulated in the same order of bird species only to add at the end additional species newly recorded for the year.
Tallies were made in two basic tables, one for wooded area with small ponds, the other with big moats used as duck resort in winter and heron colony in summer.
The number of species and number of individuals recorded per one census day ranged 15-32 (av. 23.9) species and 275-789 (av. 496.1) birds, which were slightly higher than in the previous year but reflecting a stable status of common birds. The total number of species recorded for 1973 was 53, which is 59.5% of the species so far recorded (89 species) during recent years, thus quite many species on the recorded list are lacking for 1973, as in each previous year.
Four species, Eophona migratoria, Motacilla grandis, Otus scops and Falco columbarius, were added to the bird list of the Imperial Palace. The kingfisher Alcedo atthis reoccurred in 1973-74 winter after its disappearance since 1963. Some observations and records on the flocking, feeding and breeding (nest boxes for Great tit and Mandarin Duck) of birds, especially of the Great tit and Green Pheasant, are tabulated, with also some records of insects, etc.