Snow Geese
To those who have seen it, cottongrass means beauty and perhaps a dried flower
arrangement. But to a snow goose, the plant means fat, energy, and survival. To get it,
thousands of these birds fly hundreds of miles to dine at a very special table - the Arctic National
Wildlife Refuge.
The geese come from their nesting grounds in Canada. They gather on the Refuge and the
Canadian coastal plain for only a few weeks in late August and September.
Having just raised their young, the adult geese are low on energy. The young geese are still
growing. All of the birds need to put on fat quickly. Why? Winter storms will soon drive them
south along Canada's Mackenzie River to California and Mexico. When the geese leave, they'll
fly nonstop more than 1,200 miles before they rest and feed again. The fat will supply the energy
they need.
The geese get much of it by eating the underground stem bases of cottongrass, a highly
nutritious and digestible plant food. They look for areas of wet tundra where there are few other
plants growing.
The birds feed like crazy - up to 16 hours a day. They eat as much as a third of their weight
every day, increasing their body fat by 400% in only two to three weeks - the same as a 150
pound person gaining 30 pounds of fat.
The geese gather in different places each fall. In some years, many of the birds feed on the
Refuge coastal plain, often between the Okpilak and Aichilik rivers. In other years, a majority
stay on the coastal plain in Canada. Numbers seen on the Refuge range from 13,000 to more
than 300,000 birds.
Good cottongrass feeding sites are small, patchy, and widely dispersed; there's never much
food at one place. The sites make up only about three percent of the Refuge coastal plain. Snow
geese, especially young birds, need access to large, undisturbed areas so they can find these sites
and get enough food - and fat - to survive migration.
The patchwork of gold and crimson tundra, the cool, crisp air, the waves of snow-white birds
against a cobalt blue sky -together this is what makes fall on the coastal plain such a magical
time, and the Arctic Refuge such a wonderful and important place.
Information about snow geese on the Arctic Refuge is available in:
Brackney, A. W. 1990. Distribution, abundance, and productivity of fall
staging snow geese on the coastal plain of the Arctic NWR, 1989. Pages 11-13
in T. R. McCabe, editor. Annual Wildlife Inventories: 1002 Area - Arctic NWR
Annual Progress Report 1989. U.S. Fish and Wildlife Service, Anchorage, Alaska.
Brackney, A. W., and J. W. Hupp. 1993. Fall diet of Snow Geese staging in
northeastern Alaska. Journal of Wildlife Management. 57:55-61.
Hupp, J. W., and D. G. Robertson. 1992. Potential impacts of petroleum
development on Lesser Snow Geese staging on the Arctic Coastal Plain. Pages 207-230
in T. R. McCabe, B. Griffith, N. E. Walsh, and D. D. Young, editors. Terrestrial
Research: 1002 Area - Arctic NWR Interim Report 1988 - 1990. U.S. Fish Wildlife
Service, Anchorage, Alaska. 432 pp.
Hupp, J. W., and D. G. Robertson. 1998. Forage site selection by lesser snow
geese during autumn staging on the Arctic National Wildlife Refuge, Alaska. Wildlife
Monograph No. 138. 40 pp.
September 12, 2008
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