Focus On Planet Earth - SOUTH AMERICA ECOSYSTEMS MARINE AND COASTAL ENVIRONMENTS.

SOUTH AMERICA ECOSYSTEMS MARINE AND COASTAL ENVIRONMENTS

By the year 2000, more than three quarters of the U.S. population is expected to reside in coastal communities, with concomitant effects on land use (PCSD, 1996). The figure is much lower in Canada, about 25 per cent. Canada has the longest coastline in the world, fronting on three oceans (Government of Canada, 1996). Not surprisingly, the sustainable use of marine ecosystems is thus crucial to the future of both nations. (See Figure 2.21.)

The populations of some estuarine, inshore, and offshore fisheries have been reduced to drastically low levels in North America by overfishing, loss of habitat, and land-based pollution. From 1980 to 1989, reports from more than 3,650 events with disastrous impacts on fish populations cited the loss of 407 million fish in coastal and near-coastal locations in the United States (EOP, 1993; EPA, 1996a). In eastern Canada, acid rain is responsible for habitat degradation and the loss of fish in thousands of lakes and rivers, including a number of former salmon streams (EPA, 1996a). Pollution has also caused the disappearance of some formerly fished species and the decline of some others in the Great Lakes-St. Lawrence River system (EPA, 1996a).

Approximately 1,000 species of fish live in Canadian waters; fewer than 200 live in fresh water, the others live in salt water along the Atlantic, Arctic, and Pacific coasts. Four stocks or species are thought to be extinct, two are no longer found in Canadian waters, and 49 are listed as endangered, threatened, or vulnerable. Declining fish stocks have resulted in the collapse of the East Coast fisheries, with a devastating impact in eastern Canada (Environment Canada, 1996c).

United Nations Environment Programme