摘要:We identified 97 Rangifer tarandus and 17 Ovibos moschatus populations in Canada. In July 1991, the Canadian populations totalled 1.9 to 2.6 million caribou, 13 600 reindeer and 108 600 muskoxen. Seven barren-ground caribou populations contributed about 75% to Canada's total number of caribou. Most population trends of these barren-ground caribou had shiftet from increasing in the early 1980s to stable or decreasing in the late 1980s. The George River herd of Quebec and Labrador has been decreasing since 1987, but remains the largest Canadian caribou population. The ecological factors driving barren-ground caribou population dynamics are not well understood. Arctic islands caribou are about 17% of all Canadian caribou. Over 60% of Arctic islands caribou occurred on Baffin Island. Most Arctic islands populations were decreasing with the exceptions of Southampton, Bathurst, Victoria and Baffin islands. Movements within and between islands are not well understood, and probably limit the usefulness of small surveys for indicating long-term trends of Arctic islands caribou populations. Woodland caribou form about 7% of all Canadian caribou, with about 40% of these occurring on the island of Newfoundland. Most Canadian woodland caribou have not been well studied or censused. In many areas, they were faced with an increasing rate of habitat loss. Exceptions included: some eastern Yukon populations and most Newfoundland populations which were increasing. Over 70% of the Canadian muskox population occurred on Banks and Victoria islands. Almost all muskox populations were increasing, especially those on Banks, Victoria, Melville and Bathurst islands. Muskoxen on the mainland Northwest Territories are re-colonizing southern portions of their historical distribution.