Focus On Planet Earth - NORTH AMERICA BIODIVERSITY.

NORTH AMERICA ECOSYSTEMS BIODIVERSITY

Canada s wildlife heritage is estimated to encompass 138,000 species, including 4,000 vascular plants, 1,800 vertebrates, and more than 44,000 invertebrates (Environment Canada, 1996b). As of 1996, 254 species, subspecies, or populations in Canada were considered endangered, threatened, or vulnerable; another 21 species were already nationally or globally extinct (Government of Canada, 1996b). (See Figure 2.20.) Pressures on native wildlife are also reflected in the presence of toxic contaminants in tissues of living organisms and in the ongoing invasions of non-native species, such as the purple loosestrife and the zebra mussel. Encouraging signs include an increase in populations of ducks and some species of geese; progress in efforts to restore endangered species such as the peregrine falcon, swift fox, and whooping crane; and declining levels of toxins in tissues of living organisms (Government of Canada, 1996).

There are about 2,800 protected areas in Canada, excluding private lands and cultural heritage sites. Nearly two thirds of their total area is strictly protected, but most sites are smaller than 10 square kilometres. Of the 217 terrestrial eco-regions in Canada, 71 have no protected sites (Government of Canada, 1996). Preliminary modelling has suggested that 7 per cent of Canada is at high risk of biodiversity loss, and only 25 per cent is at low risk (Environment Canada, 1996a). In an effort to protect biodiversity, Canada continues to add to its networks of parks and other protected areas, as well as to legislation (Government of Canada, 1996).

The United States has also made strides in the protection of its natural resources. By 1994, for example, 5.7 million hectares across the country were protected through land trusts. Private and voluntary efforts have resulted in a 49-percent increase in the area under conservation since 1990. While public lands play an important role in this respect, private lands are also critical because they account for 64 per cent of the continental United States. Moreover, of the 728 species listed as endangered or threatened (under the Endangered Species Act), about half are found on a combination of public and private lands. To date, existing laws and regulations have not been entirely adequate to safeguard the nation s biological diversity (PCSD, 1996).

United Nations Environment Programme