Ship Speed Limit May Help Rare Whales Survive Strikes

The whales feed off a type of plankton found in the Bay of Fundy, Cape Cod Bay, the Gulf of Maine and other waters of the North Atlantic. But warmer water boosts the viability of the calves, and so the pregnant females migrate south past the ports of Boston, New York, Philadelphia, Baltimore, Norfolk, Charleston, Savannah and Jacksonville.

The whales call to one another and can locate objects with their sonar, but they are effectively blinded to the approach of ships by the disorienting racket of ship engines. The sea is filled with noise -- what researchers call ensonification. The underwater cacophony may provoke whales to surface, putting them at greater risk of a ship strike.

"The ocean is no longer a pristine place, and where these animals particularly congregate is more or less like being on the streets of New York City," said Philip Hamilton, a research scientist with the New England Aquarium.

Hamilton has put together the North Atlantic Right Whale Catalog, a searchable online database that helps researchers track the movements of individual whales. Each one has distinct markings, particularly callosities, extremely rough patches of skin on the whale's head and lips. These "urban whales" also have plenty of scars from propellers and entanglements with fishing lines.

No one knows precisely how long a right whale can live, but it may be more than 100 years. The related bowhead whale can reach 200 years. The oldest documented right whale, which never received a name but is listed in the catalog as No. 1045, was first seen and photographed in 1935 with a calf off the coast of Florida. Fishermen harpooned the calf and then shot both the calf and the mother.

For eight hours the mother stayed with her injured calf. It finally died, and the mother swam away.

In the 1990s, researchers came across a news clipping of the 1935 incident and realized that the whale matched a female photographed in 1959, 1985 and 1992. She was believed to be at least 70 years old when, in 1995, she received a severe wound from a propeller. She was never seen again.