Snow Goose Population Threatens Arctic Tundra Habitat

Back to Map Page May, 1999 As spring returns to Canada, natural resource managers are bracing for the arrival of one species that has prospered extremely well in recent years: the lesser snow goose. Migrating from southern states by the thousand, these geese return to nest in the Canadian arctic every summer. Beautiful snow-white birds, or sometimes blue-grey, snow geese are becoming a problem because they are overpopulating their summer range. The delicate tundra vegetation is being over-grazed, and other species are losing nesting territory as the snow goose population grows. The greatest damage has been observed so far in the eastern arctic and the west coast of Hudson Bay. Flourishing populations of lesser snow geese threaten habitat of other birds Lesser snow geese are flourishing because they are very lucky in their winter habitat. They spend a long fall migration period and the winter in the southern United States, where rice has become a widespread crop in recent years. Flooded winter rice fields, still holding plenty of scattered rice grains and other vegetation, provide an ideal food source for the migratory snow geese. When spring comes the geese are fat and healthy, with fewer than normal winter fatalities. As a consequence, breeding populations in the spring of 1999 were over 5 million, three times the population just 30 years ago. There are three species of mostly-white geese. Lesser snow geese and Ross' geese are smaller and are the main source of tundra destruction, especially in Canada's central and eastern Arctic and sub-Arctic (see map). Greater snow geese look similar to lesser snow geese except for their size, and they tend to travel and nest along the coasts of North America. In addition to their growing numbers, lesser snow geese are considered the greatest risk to tundra habitat because they are more aggressive than other species in grubbing out the roots of plants, as well as grazing the shoots, as vegetation becomes scarce. Migratory route of the Lesser Snow Goose; the eastern and central populations are currently causing the most concern. In response to the growing numbers, wildlife managers have established unusually lenient hunting rules in many states where the geese winter, including such measures as eliminating bag limits, extending hunting seasons, and lengthening hunting hours. It remains to be seen how successful these steps will be, since snow geese are generally more wary and difficult to shoot than other species of waterfowl. For more information, see these related web sites: Images of degradation: vegetation destruction by grubbing snow geese, from the Hudson Bay Project Snow geese: information from the U.S. Fish and Wildlife Service Further information from the U.S. Fish and Wildlife Service Species and distribution information To read more, see Environmental Science, a Global Concern, Cunningham and Saigo, 5th ed. Population dynamics and carrying capacity: p. 121-124 Density-dependent factors in population regulation: p. 128-130 Tundra: p. 97 Environmental Science, Enger and Smith, 6th ed. Dundra: pl. 84-85 Latitude effects on biomes: p. 85-86 Population principles: p. 99 Carrying capacity: p. 99 Back to Map Page feedback form | permissions | international | locate your campus rep | request a review copy digital solutions | publish with us | customer service | mhhe home Copyright ©2001 The McGraw-Hill Companies. Any use is subject to the Terms of Use and Privacy Policy. McGraw-Hill Higher Education is one of the many fine businesses of the The McGraw-Hill Companies.