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Seven subspecies of Canada geese visit the Ridgefield National Wildlife Refuge. 
Canada geese are the most common and best-known geese. Both male and female Canada geese have similar coloration and are identified by a black head and long black neck, broad white cheek patches, and characteristic honking. Their webbed feet help them swim and dive. Dusky Canada geese are one of seven subspecies of Canada geese found on the refuge. Each subspecies varies in size and color, but most have similar habits. A chocolate brown breast is one feature that sets dusky Canada geese apart from other geese subspecies. Like all waterfowl, dusky Canada geese migrate. Dusky Canada geese migrate from their summer nesting grounds in Alaska to their wintering grounds in the Pacific Northwest, using the migratory route known as the Pacific Flyway. top of page Canada geese, such as the dusky, are very social, except when they are nesting.
Canada geese forage in in large flocks, grazing in open fields as they feed on grasses and other vegetation. Like most waterfowl, geese are flightless for about a month during mid-summer when they grow new wing feathers. Predators of Canada geese and their eggs include foxes, coyotes, wolves, bears, wolverines, gulls, eagles, and ravens. top of page The Ridgefield National Wildlife Refuge was established in 1965 to protect dusky Canada geese.
The only place the dusky Canada goose spends its winters is along the lower Columbia River and in the Willamette River Valley of Oregon. The only place it spends its summers and nests is along the Copper River Delta in Alaska. In 1964, a violent earthquake in Alaska lifted the duskys' nesting grounds on the Copper River delta about 6 feet, altering their nesting habitat, and resulting in a declining population. To ensure that the geese had secure wintering areas, the Ridgefield National Wildlife Refuge was established in 1965, along with three other refuges in the Willamette Valley. Although the earthquake caused a drop in the population, Dusky Canada geese are slowly climbing back to a healthy population. top of page Like most waterfowl, geese usually fly in a "V" formation. 
Scientists have often wondered why waterfowl, such as geese, fly in a "V" formation. One theory suggests that a bird gets better lift and, therefore, expends less energy when flying behind another bird. This allows flocks to fly much farther than a lone migrating goose. Another hypothesis
is that the "V" formation allows birds to have visual
contact and to communicate, so that they avoid running into one
another while flying. Try these classroom and field trip activities to learn more about Dusky Canada geese.
Bird Matching Game: Can you match the bird's song to its picture? (requires
Flash) top of page Learn more about dusky Canada geese! Alaska Natural Heritage Program Alaska Department of Fish and Game U.S. Forest Service, Cordova Ranger District: Dusky Canada Goose Nesting Grounds US
Geological Survey: Wintering Canada Geese in the Willamette Valley Visit the other learning stations in the Birds of the Refuge field trip. |
Canada
geese pair for life, and first breed at about two to three
years of age. Pairs generally establish a nesting territory, producing
four to five eggs per nest. Canada geese raise their young as a
family, often, combining to form “creches” guarded by
several parents.
One
of the primary goals for creating the Ridgefield National Wildlife
Refuge was to provide a wintering area for waterfowl, with a special
emphasis on dusky Canada geese. 