Geoscience Reference
In-Depth Information
Bottlenose dolphins belong to three principal populations that occupy coastal waters between Long Island and Florida.
DEEP-SEA CORALS
A SURPRISING
discovery of the last two decades has been extensive deep-sea coral beds off the North Atlantic
coast. Normally, coral is associated with warm, shallow tropical waters. Two-thirds of all known coral species,
however, live in deep, cold, dark waters. Almost thirty species of corals have been identified in Atlantic
Canada alone.
The highest diversity of corals is found along the edge of the continental shelf between the Gully and the
Laurentian Channel at the edge of the Scotian Shelf. One of these, discovered only in 1992, 150 kilometers (90
miles) offshore of Canso, Nova Scotia, is the reef-forming species Lophelia pertusa. Some Lophelia reefs may
be many thousands of years old, and the largest cover several square kilometers and rise 20 to 30 meters (65 to
100 feet) above the sea floor. Other deep-sea corals are either solitary or form tree-like structures with a main
stalk and branches. One of the latter is a gorgonian coral known as bubblegum coral for its gaudy pinkish col-
or. Growing less than 2.5 centimeters (1 inch) per year, these large bubblegum trees may be five hundred years
old. Ten species of these gorgonian corals are found in the deep waters of the Scotian Shelf, of which nine are
found in the area of the Gully. A large aggregation of gorgonian corals also lies in a deep channel between
Browns Bank and Georges Bank, 150 kilometers (90 miles) south of Nova Scotia.
