June 11,
2004
Snow-goose paradise
Researchers expect 600,000
greater snow geese in the High Arctic
JANE
GEORGE
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The
wetlands of Qarlikturvik Valley on the southwest of Blyot Island are an ideal
habitat for greater snow geese. Every year since 1988, researchers have headed
to Bylot to study these birds. (PHOTOS COURTESY OF GILLES GAUTHIER)
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Thousands of greater snow
geese will be laying eggs on Bylot Island tomorrow in an annual exercise that
attracts researchers tracking the phenomenal growth of this bird population.
Their project started in
1988 as a collaboration between the northern studies centre, Centre d'études
nordiques at Université Laval, and the Canadian Wildlife Service. Fifteen
years later, it's the most intensive scientific investigation ever conducted
on Bylot Island and one of the largest and longest ecological studies in Nunavut.
The effort to reduce the
numbers is also a conservation success story, says Gilles Gauthier from Université
Laval in Quebec City.
Gauthier spends part of
his summer, along with students and field assistants from Pond Inlet, in a base
camp located in a large glacial valley at the southwest end of Bylot Island.
The wetlands of the Qarlikturvik
valley are home to one of the world's largest breeding colonies of greater snow
geese.
Considered an important
site for many migratory birds, Bylot Island was declared a migratory bird sanctuary
in 1965. Established in 2001, Sirmilik National Park encompasses most of Bylot
Island, except for a few pockets that are Inuit-owned lands.
Austin Reed, a retired
biologist with the Canadian Wildlife Service who now sits on the Sirmilik National
Park Joint Management Board, first came to Bylot because the enormous growth
of the greater snow geese population was a "subject of considerable concern."
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About
55,000 greater snow geese return to Bylot Island every year to breed in the
wetlands of Qarlikturvik.
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Millions of lesser snow
geese, a related bird population, had already devastated many western Hudson
Bay areas.
At the beginning of the
1900s, greater snow geese nesting in the High Arctic numbered about 6,000, but,
by the 1990s, there were as many as 900,000, and the population was doubling
every eight or nine years.
The numbers of geese rose
when Canada limited hunting to the autumn, and the U.S. cut it out entirely
until 1975.
Between 1983 and 1993,
the numbers of geese on Bylot Island increased from 16,600 to 55,000 birds.
"With this increase
in the population, the vegetation on Bylot was more vulnerable," Reed says.
"We could be getting to a point where there would be serious damage to
the Arctic tundra because of the abundance of geese."
The numbers of greater
snow geese also increased because they found new feeding areas in the South.
"At about that time
they started running out of food in the marshes. In their search to find more
food, they moved into agriculture land. That's what has really triggered this
huge increase, because they were so well fed," Reed said.
In 1999, at the recommendation
of biologists, hunting seasons were expanded, so Canadian hunters would shoot
geese in the autumn and in the spring and the U.S. hunters would resume hunting
geese in the winter. This combined hunt has taken up to 250,000 a year, reducing
the population significantly.
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Thousands
of chicks hatch, but not all will survive the summer or the long migration south
in August.
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In some years, 1.3 million
birds return from the North.
Last year, the numbers
of greater snow geese stabilized at 600,000, a number Reed and other biologists
say Bylot Island can support.
Greater snow geese leave
the Arctic at the end of August and migrate south through central Quebec where
they stay from six to eight weeks in tidal marshes along the St. Lawrence River.
From there, a 900-km non-stop
flight south brings them to their wintering grounds in the U.S. mid-Atlantic
states. The birds depart from their wintering grounds in late March, arriving
in their breeding grounds by early June.
During the nesting period
in June and early July, the geese that breed on Bylot are concentrated a few
kilometres north of Dufour Point near the coast.
In this colony, the density
of nests is high, averaging over 400 nests per square kilometer.
After hatching, many families
spread out throughout the island, concentrating in the wetlands.
Every year, researchers
check the date at which birds start laying their eggs and the date that eggs
hatch, the density of nests and the number of eggs per nest, and finally their
nesting success. Nests are considered successful if at least one egg hatches.
Numbers
of greater snow geese in the High Arctic rose to 900,000 in the 1990s before
increased hunting reduced their numbers
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The follow-up continues
during the summer when birds move to the brood-rearing area. The most important
research activity during this period is the capture and banding of large numbers
of goose families in late summer in order to track their annual migrations.
To monitor the number and
distribution of geese on Bylot Island, the Laval team has been conducting aerial
surveys during the brood-rearing season at five-year intervals since 1983.
Every August since 1990,
the team has caught several thousands of birds in nets over a few days, marking
all birds with a small metal leg band and many adult females with plastic neck-collars,
to note where the birds travel.
Researchers are also studying
Arctic foxes, lemmings, snowy owls and vegetation.
Climate change may be also
be a factor in the increasing number of geese, particularly because the average
annual temperature has risen two degrees Celsius on Bylot Island over the past
27 years.
Gilles
Gauthier (left) and Austin Reed (right) catch several thousands of geese in
nets over a few days, marking all birds with a small metal leg band and many
adult females with plastic neck-collars, to note where the birds travel.
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To provide updates on the
growing amount of information from the Bylot Island project, there's now a Web
site on ecological studies and environmental monitoring on Bylot Island, at:
www.cen.ulaval.ca/bylot/.
This site is in English
and French, and by the end of the summer, will also have an Inuktitut version.
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