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Grand Banks Beneath the cold, choppy waters off the coast of the Canadian province of Newfoundland and Labrador, the North American continental shelf plunges deep into the floor of the Atlantic Ocean. Here, where the arctic Labrador Current meets the warm Gulf Stream, Newfoundland's Grand Banks provide some the richest fishing grounds on earth and some of the most treacherous shipping routes in history. Geography The Grand Banks make up only a part of North America's broad continental shelf. Formed by the movement of the earth's tectonic plates and the wrenching apart of one continent from another, the shelves surround every continent. They mimic the deep valleys and vast plateaus of land's visible contours. Scientists believe that about ten thousand years ago, at the end of the last ice age, the added water from melting glaciers caused the Atlantic Ocean to rise, claiming the coastline of what are now Canada and the eastern United States. When water levels stabilized, the North American coast was sunk only 25 meters (82 feet) below the surface of the Atlantic in some areas, and more than 700 meters (2,300feet) below the surface in others. The submerged land off the Canadian coast is broader that anywhere else on the North American seaboard. It is also one of the widest stretches of continental shelf in the world, stretching out 480 kilometers (300 miles) from the shore. Along the southern coast of Newfoundland, the ground rises up below the water to form a vast series of banks 730 kilometers (450 miles) long and covering some 280,000 square kilometers (174,000 square miles) in total. Underwater Life Between underwater banks high enough to let sunlight through to the ocean's floor, deep trenches plunge miles under the water's surface, creating upwells of cold ocean bottom water. This submerged landscape creates a unique environment for marine life. The presence of sunlight at the ocean's floor allows for aquatic plants that depend on photosynthesis, the conversion of energy from sunlight into oxygen and usable sugars. The result is a lush underwater environment where an incredible assortment of fish and other marine life spawn, birth, and feed. Atlantic cod, herring, halibut, lobster, and scallops, among others, flourish in the waters of the Grand Banks. With fish and shellfish come seabirds. Endangered harlequin ducks, rare shearwaters, petrels, and kittiwakes feed on the plentiful takings from the sea. Marine mammals, including several types of seals, swim among porpoises, dolphins, and at least eight different species of whale. By Amy Witherbee Source: Canada's Heritage: Grand Banks, 2005, p1, 1p