Taiga Bean Goose at Sarobetsu, Japan 41
©Wildfowl & Wetlands Trust
Wildfowl
(2013) 63: 40–55
the world population of
c
.70–80,000
individuals (Delany & Scott 2006;
Syroechkovskiy 2006),
c
. 9,000 winter in
Honshu, Japan (Syroechkovskiy 2006;
Ikeuchi 2010). The Sarobetsu area in
northern-most Hokkaido is considered to
be one of the key staging sites for Taiga
Bean Goose along the East Asian flyway
(Miyabayashi & Mundkur 1999), yet little
information has been available on the
numbers and distribution of geese using the
area (Japanese Association for Wild Geese
Protection 2002).
In 2002, after preliminary observations in
1998–2001, regular counts were initiated to
clarify the abundance and distribution of
Taiga Bean Geese in the Sarobetsu area and
to understand their staging behaviour. The
spring and autumn surveys aimed to
describe the birds’ migration phenology, for
informing conservation measures for the
species. This paper presents information on
the number of staging birds counted at
Sarobetsu in autumn and spring, and on
their spatial distribution within the area.
Likely numbers and staging periods of Taiga
Bean Geese migrating through Sarobetsu
and the conservation implications for this
near-threatened population are discussed.
Study Area and Methods
The Sarobetsu Plain (45°05’N, 141°42’E)
covers 216 km
2
in the Soya region of
northernmost Hokkaido, Japan (Fig. 1).
Habitat on the plain is predominantly of
moorland and fresh water lakes, with the
main lakes of Kabuto (1.46 km
2
), Penke
(1.3 km
2
) and Panke (3.47 km
2
) being
surrounded by farms given mostly to
pasture. The study area, which is located
within the plain, is
c
. 31 km from north to
south (from Lake Kabuto to the Teshio
River basin), and extends
c
. 7 km from east
to west (Fig. 2). Lake Penke, in the middle of
the study area, was designated a Ramsar site
in 2005 partly because of its importance as a
key staging site for the Taiga Bean Goose
and Bewick’s Swan
Cygnus columbianus
bewickii
along the East Asian flyway
(Wetlands International 2005). Greater
White-fronted Geese
A. albifrons frontalis
and
Tundra Bean Geese
A. f. serrirostris
also
occur in smaller numbers in the Sarobetsu
area in autumn, and nationally important
numbers of Lesser White-fronted Goose
A.
erythropus
are also observed annually (Ikawa
& Ikawa 2009). In spring, oxbow lakes and
pastures on the lower reaches of the Teshio
River are the first to be used by various
species of waterbirds, mainly by Taiga Bean
Geese and Greater White-fronted Geese,
with large numbers of Whooper Swans
Cygnus cygnus
and Bewick’s Swans also
occurring in the area. As the ice melts,
waterbirds occur at other sites within the
Sarobetsu staging area as well.
The study area was divided into five
zones from north to south, based on the
main roost sites used by Taiga Bean Geese:
A) Kabutonuma and Asaru districts in
Toyotomi Town (main roost = Lake
Kabuto); B) Ochiai and Hotoku districts in
Toyotomi Town (main roosts = Lake
Kabuto and Lake Penke); C) Nishitoyotomi
and Shinsei districts in Toyotomi Town and
Shimonuma district in Horonobe Town
(main roost = Lake Penke); D) Akebono
and Oiwake districts in Horonobe Town
and Furaoi district in Teshio Town (main
roost = Furaoi Oxbow Lake); and E)
