The migration course of geese wintering at Lake Izunuma (2)

Abstract

The authors have been endevouring to survey the migration course in spring of the geese wintering at Lake Izunuma in Miyagi Prefecture, Northern Japan.1. Late in April 1975, we found flocks of wild geese on the Ishikari Plain in Hokkaido. The flocks consisted of approximately four thousand of White-fronted Geese (Anser albifrons frontaris Baird) and two Aleutian Canada Geese (Branta canadensis leucopareia (Brandt)).They roost at night on Ishikari Bay on Japan Sea coast, about thirty kilometer west of Ishikari Plain. On clear days, they feed on paddy fields of Ishikari Plain in the early morning and late afternoon, and return in the midday to Ishikari Bay. On cloudy or rainy days, however, the geese remain on fields longer, sometimes all day long.2. Judging from data, it seems that the flocks geese observed on Ishikari Plain are those which have migrated from Hachirogata in Akita Prefecture. The following table shows the number of geese on Hachirogata and Ishikari Plain and the relevant dates.a. Number, species and date.(Total number of geese at Hachirogata includes that of Bean Geese.)b. Aleutian Canada Goose.The Aleutian Canada Goose is a rare bird in Japan and only two have been found in 1975. The two Aleutian Canada Geese disappeared from Hachirogata with other geese in the middle April and reapeared on Ishikari Plain in the same season. They are considered to be identical.3. We may conclude that in spring the geese which have wintered at Lake Izunuma, may first migrate to the paddy fields of Hachirogata on their way to north and then arrive on Ishikari Plain for resting and feeding. They stay here till early May.