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The Lesser Snow Geese
visiting the Sanctuary are part of the Wrangel Island (Pacific
Flyway) nesting population. Wrangel Island lies in the Arctic
Ocean, north of Siberia, and belongs to Russia. A "population" is
the number of animals of the same type living in an area.
Birds nesting on Wrangel Island split into two separate wintering
sub-populations. One winters in California, and one winters
locally.
Lesser Snow Goose Facts:
Weight:
2.5 to 2.7 kg Wingspan: 38- 46 cm Lifespan:
10 to 20 years in the wild.
Distinguishing marks: White bodies, black wing-tips, a pink
bill with black markings and pink feet.
Best times to view them
at the Sanctuary: mid-Oct. to mid-Dec. and mid-March to mid-April.
January 2012 Mid-winter count (Fraser
River and Skagit River flocks)= 70,000 birds, an increase
over last year's 65,000 birds. |
Lesser Snow Geese generally mate for life, and raise an average
of three or four young each year. The young migrate with their parents.
During the summer, adult geese and the new young birds are all flightless.
Scientists from Canada, the United States and Russia all work together
to capture some of these birds during this flightless period to
mark them so that their migratory paths can be better understood.
These birds fly 5,000 km between Wrangel Island and the Sanctuary.
Their migration stops between nesting and wintering grounds include
the Russian mainland, St.Lawrence Island (Bering Sea), the Yukon-Kuskokwin
delta (western Alaska), Cooke Inlet (southern Alaska), and the
mouth of the Stikine River in northern BC. Some marked individuals
have made non-stop flights between Alaska and the Sanctuary (2500
km) in less than 36 hours.
Our Snow Geese start arriving at the Sanctuary by early October
and are often referred to as the "Fraser-Skagit" flock
or subpopulation, as they move back and forth between the estuaries
of the Fraser and Skagit Rivers. The Sanctuary is in the center
of the Fraser River estuary. The Skagit River estuary is just
south of the Canada/United States border in the State of Washington,
and it provides the birds with similar habitats to what they
find in the Fraser River estuary- flat farmland next to extensive
intertidal marshes. Each area has traditionally suppored approximately
50% of the flock in the fall, with nearly all of the flock
moving to the Skagit estuary from late December to
February. Birds return to the Fraser estuary in spring, and depart
in April for their northward migration to Wrangel Island. Nesting
pairs are on their nests and incubating eggs most of June, and
the resulting young are ready to fly by late August.
During their stay here, favourite natural foods for these birds
are the intertidal marsh plants of the estuary. Marsh plants such
as bulrush (Scirpus americanus) store starch reserves in their roots
and rhizomes. The geese dig up these food sources using their strong
bills. The soils in the Delta area are rich in iron compounds, and
stain the head feathers of the geese orange when they have been
digging in the marsh. In the spring, the green growth of pastures
and marsh plants such as sedge (Carex lyngbeyi) are popular foods.
Agricultural crops are also eaten, although most are harvested
by farmers before the snow geese arrive. Leftover potatoes often
remain in the fields, and the geese dig these up. Local farmers
all participate in a program called “Greenfields” which
coordinates the fall planting of green growing grass cover for
these geese, other wildlife and soil enrichment through the Delta
Farmland and Wildlife Trust.
The snow geese provide spectacular wildlife viewing for our visitors.
They travel together in very large dense flocks of up to
20,000 birds which feed, rest and fly over the Sanctuary, neighbouring
farmland and nearby Fraser marshes every day. They are restless
and constantly moving when Bald Eagles, people and dogs are nearby.
Within the flocks, visitors can often identify family groups. The
young born that year are fully grown before they migrate to this
area, but their first set of adult feathers is grey, not white.
Small groups containing two white birds and several darker birds
are likely family groups. The snow geese regularly sleep on the
water in large dense flocks, sometimes out in the marshes of the
estuary, and sometimes in the quiet river channels around the Sanctuary.
Visitors can be of assistance to the ongoing international research
projects by reporting any marked birds, as over 2,000 birds have
been individually marked with coloured neck collars or tracked after
the installation of radio-transmittors as part of migration and
population studies.
For more information within this site:
Snow goose
research and farm programs supported by BCWS
Comprehensive teacher
package on migration and specifically snow geese
For an annual population update and more complete
information on the status of this species, which is considered
an indicator species for the health of ecosystems in the Strait
of Georgia:
http://www.ecoinfo.ec.gc.ca/env_ind/region/snowgeese/snowgeese_e.cfm
For a comprehensive review of snow geese across North America: Hinterland
Who's Who
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