Sargasso, << sahr GAS oh, >> Sea is an irregular oval-shaped area of the North Atlantic Ocean. Its center is about 2,000 miles (3,200 kilometers) west of the Canary Islands. It lies roughly between the 20th and 40th parallels of north latitude and between the 35th and 75th meridians west of Greenwich. No land boundaries mark off this body of water from the rest of the open ocean. It is set apart only by the presence of seaweeds that float on its surface. It is also a region of slow ocean currents surrounded by a boundary of rapidly moving currents, such as the Gulf Stream and the North Equatorial Current. The Sargasso Sea derives its name from sargaco, a Portuguese word for seaweed. Christopher Columbus is given credit for the first reliable report on this region. He took tests in 1492 to make sure that no rocks lay beneath the sea’s weeds.
The legends of the sea
The early navigators who sailed their small ships to North America saw the Sargasso Sea as patches of gulfweed that seemed to form wide-spreading meadows. Soon there were legends and myths about the region that told of large islands of thickly matted seaweed inhabited by huge monsters of the deep. Poets and novelists used their imaginations in describing the sea. They pictured a blanket of netted seaweed from which no ship could escape once it became tangled in the weeds. They described many of the ghost ships of the past as huddled together in a weaving, rotting mass. Shapeless hulks of ancient galleons, covered with weeds and barnacles, were pictured lying beneath the waters of this mysterious sea. The passing years contributed skeletons of slave ships, then of pirate ships, and later of the gallant ships of Revolutionary War days. Wrecks of clipper ships and the latest doomed ships completed the legendary collection.
The facts about the sea
Scientists have changed the picture of the Sargasso Sea. They have shown that its area is about 2 million square miles (5.2 million square kilometers), and they have opened up fascinating research problems.
Origin of the seaweed.
Scientists believe that the seaweed first came from the shores of the West Indies, after it had been torn loose by wind and waves. Parts of it adapted to living and growing in the open sea. The weeds developed a method of reproduction that enables them to multiply and grow without producing seeds. Waves break off sections of the mature weeds. These fragments then grow into full-size seaweeds in the same way that a cutting from a grape plant grows into a large grapevine. The weeds are supported by air sacks which resemble tiny grapes and grow as a part of the weeds. Sargassum weeds grow in many ocean regions. One variety is used as food in Japan.
Many small marine animals have adapted themselves to growing on and among the weeds. These animals include tiny crabs, shrimps, and barnacles. Sargassum fish are difficult to distinguish from sargassum weeds, because the fish have taken on the colors and patterns of the weeds.
Two kinds of eels known as the American eel and the European eel begin their lives in the Sargasso Sea. The young eels migrate to fresh water. But each fall, large numbers of mature eels return to the Sargasso Sea to breed.
The greatest quantity of seaweed is found in the central part of the Sargasso Sea. It occurs in scattered masses, some 100 feet (30 meters) in diameter. Wind action forms long strips of the weed, which follow the general direction of the wind. Patches of the weed may cover more than 1 acre (0.4 hectare). Nowhere is the region so thickly covered that the weeds can interfere with the movements of a ship. Sometimes, unusually strong winds or currents cause some of the weeds to drift into the Gulf Stream, and eventually to New England or even Ireland and Norway.
Waters of the sea.
The waters of the Sargasso Sea have many distinctive features. The water has an unusually deep blue color; a high salt content (3.7 percent); a high temperature (up to 83 °F, or 28 °C); and extreme clearness (light can penetrate to a depth of as much as 3,300 feet [1 kilometer]). These features result chiefly from the location of the sea and its great depth, averaging over 3 miles (4.8 kilometers). However, because water largely circulates within the sea, oil and solid-waste pollution sometimes collect there.
