Offshore from Nova Scotia, New Brunswick, Maine, New Hampshire, and Massachusetts is "New England's own ocean," the Gulf of Maine. Shallow underwater banks of sand and gravel, primarily Georges Bank and Brown Bank, form its eastern rim and separate the Gulf from the rest of the Atlantic Ocean.
In the spring, rivers carry melting snow to the Gulf of Maine. This makes it colder, less salty, and more fertile than the deeper Atlantic Ocean. The rivers carry food, minerals and decaying plants to the many microscopic plants and animals of the Gulf plankton. Huge tides, as much as 40 feet high, help to mix the waters of the Gulf. A gyre, a circular current, fueled by the spring snowmelt of rivers flowing into the sea, moves nutrients, plankton, fish, and pollution in a counterclockwise direction around the Gulf. In addition, as colder, dense surface water sinks in spring, it displaces and pushes up the bottom water that is rich in nutrients that have sunk to the bottom of the Gulf. This process is called upwelling.
These nutrients, from rivers, runoff and upwelling, nourish vast quantities of life from microscopic plankton to the whales that visit the Gulf of Maine each summer. Like other tourists, humpbacks, fin whales, and minke whales enjoy the cool waters and the abundant food. In the winter, they migrate to the tropics where the mothers give birth.
Plankton is the food that nourishes all life in the Gulf, directly or indirectly. The term plankton means "wanderer," and these organisms swim only feebly or are moved passively by the wind, waves, and currents. Phytoplankton, plant plankton, are the basic producers in the sea, as green plants are on land. They use the energy of the sun to produce oxygen and starches and sugars. Phytoplankton reportedly produce 80% of the oxygen we breathe.
Many animals, including tiny floating zooplankton, feed directly on plant plankton. Zooplankton increase dramatically when phytoplankton bloom, responding rapidly to the increase in food supply.
Most zoo plankton are microscopic, but some larger animals like jellyfish, amphipods, and arrowworms, are also considered zooplankton. Many other marine animals, including lobsters, fish, crabs, barnacles, and oysters, begin their lives as zooplankton. In their larval stage, they look little like their adult forms. Other zooplankton, copepods, for example, spend their entire lives as plankton.
Many bottom-dwelling animals, such as mussels, ocean quahogs and scallops feed on plankton. They, in turn, are eaten by the fish that live on or near the bottom, such as, cod, haddock, hake, and flounder. These are known as groundfish.
Groundfish and herring (young ones are called sardines) usually swim in large schools. Schooling helps to protect fishes from their ocean predators, but it's this characteristic that makes them harvestable by commercial fishermen.
Fishermen have been harvesting the Gulf of Maine since before the Pilgrims landed at Plymouth Rock. In recent years overfishing of our traditional species has taken its toll. Now, with fewer and fewer groundfish, the most populous species in the Gulf of Maine are dogfish shark and squid. Most of these are sold overseas. Overfishing and coastal pollution that has drifted up to 200 miles from shore now threaten the fish stocks of Georges Bank, once one of the richest fishing areas in the world.
Georges Bank is a relatively shallow area within the Gulf of Maine. It extends northeast off Cape Cod, Massachusetts to about 100 miles southwest of Nova Scotia.
So many foreign fleets literally vacuumed up the fish that the US and Canada finally responded by passing their respective 200-Mile Limit Laws in the mid-1970's. These laws gave the US and Canada jurisdiction over fishery resources between 3 miles (the end of states' jurisdiction) and 200 miles from shore. This law (in the US, it's known as the Magnuson Fishery Conservation and Management Act of 1976) did help keep foreign fishermen out. But now US and Canadian fishermen, who had fished side by side for hundreds of years, jockeyed for exclusive jurisdiction over "their" economic zones. Unfortunately, the United States and Canada made overlapping claims to some of the same ocean areas, including the fertile Georges Bank.
Under their respective 200-mile limit laws the United States claimed 100% of Georges Bank and Canada claimed 35%. How did they resolve the dispute? They went to court. They agreed to international mediation. In 1985, The World Court in The Hague, Netherlands, divided the rich fishing grounds of Georges Bank almost equally between the US and Canada. Now US fishermen must stay on their side of the boundary, and Canadian fishermen are not allowed to cross into the US zone.
The Gulf of Maine is also noted for its frigid water temperatures where the average sea temperature ranges between 38F and 62F. Therefore it is critical to locate and rescue any survivor of an accident at sea before that person succumbs to the cold temperatures. One of the greatest dangers to fishermen or downed pilots in the Gulf of Maine is hypothermia, the lowering of the body's core temperature to a level where the body is unable to warm itself again. (below about 95F).
Hundreds of sailors and pilots have been saved world-wide by emergency beacons on aircraft and ships that automatically signal their locations to orbiting satellites in the event of a disaster. Airplanes have Emergency Locator Transmitters (ELT's), normally triggered by the impact of a crash. Ships carry Emergency Position-Indicating Radio Beacons (EPIRB's), which can be activated manually or by immersion in water. The emergency signal is transmitted to a search & rescue satellite which relays the signal to a ground receiving station. It informs a rescue coordination center, usually manned by the Air Force or the Coast Guard, of the vessel's location. The rescue center sends out planes, helicopters, ships, or ground search crews.