A Chronic but Mostly Hidden Problem

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Texts for Individual Reading

RART III

XXVII. Final test

1. Describe the structure of an ecosystem.

2. List various physical factors and describe how they affect the distribution of living things

3. Describe a typical food chain

4. Explain how energy flows through an ecosystem

5. Explain how materials cycle in an ecosystem

Tundra plants can be, classified into five main groups. Lichens are primitive plants without stems, leaves, or roots. They are a combination of algae and fungi that grow on rocks and the ground. A second group of plants are the mosses, which are usually found in cracks in rocks. Arctic cotton grass is a kind of grass, the third group of alpine plants, which produces a ball of white fluff that helps the plant stay warm. The tundra's most delicate-looking plants—the small flowering plants—are often the toughest. For example, the Arctic poppy has thin petals that remain on the flower even when it is extremely windy. Finally, a typical shrub in the alpine tundra is the ground willow.

Birds in the tundra are either migratory or permanent. The snowy owl, the ptarmigan, and the raven are birds that live in the tundra all year long. They have learned to survive the cold and the darkness of the winter. Two of these birds, the snowy owl and the ptarmigan, turn white in the winter. They change color so that they match the snowy background, which will help protect them from predators. With the coming of spring, however, other birds migrate to the tundra. Some of these typical migratory birds include geese, ducks, and terns.

Mammals are also both migratory and permanent residents of the tundra. The permanent residents can be further classified into three types: mammals that roam the open tundra year-round, mammals that hibernate, or mammals that dig tunnels under the snow. A typical migratory animal is the caribou, which migrates from the taiga in the spring. The chief predator of the caribou is the wolf, and this animal roams the open tundra year-round. Two other animals that roam the open tundra year-round are the Arctic hare—or snowshoe hare—and the Arctic fox. The hare and the fox turn white in the winter, just like the snowy owl and the ptarmigan, to protect themselves from predators or to surprise their prey. Grizzly bears and ground squirrels are animals that hibernate, but bears will sometimes come out of their dens during the winter. Finally, lemmings, which are small furry herbivores that look like hamsters, dig tunnels under the snow and live their lives much as they do above the ground in the summer

Acid Precipitation in Québec

In the 1980s, a lot was said in the media about acid precipitation. The strong interest in the phenomenon stemmed from the fact that our lakes, rivers and forests were located on highly sensitive soils and received highly acidic depositions. This interest was all the more significant that acid precipitation had an immediate impact on sport fishing as it resulted in the disappearance of certain vulnerable fish species from our lakes, which proved acidic. Also, in our forests acidification contributed to sugar maple dieback. But the 1980s was also the decade where countermeasures were implemented. Lake monitoring and precipitation measurement networks were set up to better define the problem and its impact on the environment. National and international agreements aimed at reducing pollutant emissions worldwide were discussed, while legislative tools to help Québec meet the reduction goals set forth in the agreements were adopted. Since the end of the 1980s, Québec has managed to lower its SO2 emissions by more than 60% with respect to 1980 levels. While Ontario has reached a similar goal, the United States will have reduced its SO2 emissions by 40% (1980 reference year) by 2010. It would appear, however, that these achievements will not be sufficient to recover the resources affected by acidification. Québec is therefore committed to seek an agreement with the other Eastern Canadian provinces for an additional 50% reduction in SO2 emissions. The government of Québec has signed a similar agreement with the Eastern Canadian Provinces and New England States addressing the problems of acid precipitation and mercury specifically.

Chronic oil pollution coming from ships traveling off Canada's coasts causes the death of hundreds of thousands of seabirds every year. An estimated 300,000 birds are killed every year off of Newfoundland's coast, and at least equivalent numbers may be dying annually on the Pacific coast, because of this illegal pollution.

Marine waters off of Canada's coasts are some of the most important places for seabirds in the world. There are tens of millions of seabirds in Canada's marine waters at all times of the year. They are attracted there by the abundant food sources and ideal breeding conditions. About 15 species of seabirds are common on the east coast and about 11 species are common on the west coast.

All of the species present on both coasts are migratory species some of which travel great distances each year from the southern oceans or across the northern oceans. As well there are occasional visitors which are rare species from other oceans of the world.

Most of the seabirds off the east coast live in waters that are criss-crossed by the busiest shipping lanes in North America largely due to the ship traffic with Europe, as well as fishing vessels at work in Canada's abundant fishing grounds. Unfortunately the owners, captains and crews of some of these ships knowingly allow the dumping of oily ship wastes into the ocean where they harm the seabirds and other marine animals.

Oil does not mix with water, but it is readily absorbed into birds' feathers. When that happens it decreases the birds' insulation from the cold, as well as their waterproofing and buoyancy. This inevitably leads to their death by hypothermia or starvation. Just one spot of oil can do this, and therefore an oiled bird becomes a dead bird.

On the east coast, and particularly in Newfoundland, a small percentage of the dying or dead oiled birds wash ashore. Therefore people have been aware of the problem there for many years. On the west coast this is still a hidden and practically unknown problem. Because of the wind, tide and ocean currents, most birds that become oiled from the vessels' wastes sink at sea long before they can wash ashore.

What the Government of Canada is Doing About the Problem

For years two Government of Canada departments have been enforcing federal legislation to charge and fine offenders for polluting our coastal marine environment.

Environment Canada uses provisions of the Migratory Birds Convention Act, the Canadian Environmental Protection Act, and the Fisheries Act. Transport Canada uses provisions of the Canada Shipping Act. In addition the Canadian Coast Guard supports the government departments in responding to marine pollution incidents.

Working closely with Justice Canada, these departments have successfully prosecuted ships, ships' owners, captains and crews that have illegally dumped oil in Canada's waters.

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