Right Whales' Wintering Ground Found in Gulf of Maine

The center's aerial survey team saw 44 individual right whales on December 3 in the Jordan Basin area, located about 70 miles south of Bar Harbor, Maine.

After centuries of whaling from the 1700s, North Atlantic right whales are nearly extinct. A worldwide total ban on right whaling was agreed upon in 1937. Only about 325 animals survive today in the western North Atlantic Ocean.

Weather permitting, the team regularly surveys the waters from Maine to Long Island and offshore 150 miles to the U.S.-Canadian border, an area of about 25,000 nautical square miles. The aerial surveys, conducted year-round, began in the 1990s.

"We're excited because seeing 44 right whales together in the Gulf of Maine is a record for the winter months, when daily observations of three or five animals are much more common," said Tim Cole, who heads the team.

Four North Atlantic right whales can be seen in this photo taken from the NOAA aerial survey plane.

"Right whales are baleen whales, and in the winter spend a lot of time diving for food deep in the water column," Cole said. "Seeing so many of them at the surface when we are flying over an area is a bit of luck."

On December 6, the team observed only three right whales on Cashes Ledge, about 80 miles east of Gloucester, Massachusetts. Cole says the whales are known to be in the region, but actually seeing any of them on any given aerial survey is unpredictable.

On December 14, the team saw 41 right whales just west of Jordan Basin.

Many female North Atlantic right whales head south in winter to give birth in the waters off Florida and Georgia, the only known calving ground for this population.

Little is known about where other right whales go in winter. Bad weather, the challenges of finding whales in such a large area, and the resources required to assess their distribution make winter sightings difficult.

"Sometimes we will see a whale we haven't seen in years, while other individuals are sighted fairly often," team member Pete Duley said, noting the existing library of photographs of individual right whales that observers have come to know by name based on the patterns of callosities, like barnacles, on the animal's heads.

"Because only about 100 right whales, mostly females and their calves, are sighted each year in aerial surveys off the southeast coast, we know the remainder of the population must be somewhere else," said Duley. "We don't know much about where these other whales spend the winter or breed, but we have recently started to look in the Gulf of Maine in winter."

With a population estimated to be about 325 whales, knowing where the whales are at any time is critical to protect them. Sighting whales can trigger a management action affording protection, such as slowing ship speeds in the vicinity of the whales.

On December 9, new federal speed rules for large ships went into effect to reduce ship strikes of whales, a leading cause of North Atlantic right whale mortality.

The aerial survey team is part of the NEFSC's Protected Species Branch based at the Center's Woods Hole Laboratory, which conducts research needed to manage protected species off the northeast coast of the United States from Maine to North Carolina.

The Southeast Fisheries Science Center in Florida, which also deploys aerial survey teams, has similar responsibilities for the southeastern region, which includes the Gulf of Mexico.

"The whales appear to follow the circulation system of the Gulf of Maine and Georges Bank and pursue their food," said Cole, who has been flying surveys for more than 15 years.

"In the winter many of the right whales seem to be in the middle of the Gulf of Maine and off Portsmouth, New Hampshire, and by early spring move into Cape Cod Bay, then the Great South Channel and then eastward toward Georges Basin," said Cole. "By mid-summer they head north into the Bay of Fundy."

The survey team has used a variety of aircraft through the years, from helicopters to seaplanes to the current Twin Otter based at the nearby U.S. Coast Guard Air Station Cape Cod. A removable window in the back of the plane allows them to take clear photographs of any right whales they see.

Other species of whales and marine mammals sighted are recorded into the data logging system but are not individually photographed.

Coast Guard Air Station Cape Cod supports the mission, providing their air field and hangar space as needed for the NOAA plane.

"This is a very resource intensive operation," Cole said. "The Coast Guard provides not only financial support but access to their facilities when we are on the Air Station. Like us, they have a responsibility to protect marine resources, so we share this mission with them."

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