BAR HARBOR, Maine — For years, whale researchers have known that endangered North Atlantic right whales tend to spend their summers feeding in the Bay of Fundy, and that pregnant female right whales travel in the winter to the waters off the coasts of Florida and Georgia to give birth.
But researchers have been unable to determine where most other right whales gather in the winter. Where do whales mate? Where do adult males, nonpregnant females and juveniles gather when air temperatures drop and daylight hours grow short?
On Dec. 18, several whale researchers headed out into the Gulf of Maine on a local whale watch boat to a place that they think might provide answers to those questions. Using the Friendship V, a catamaran owned and operated by Bar Harbor Whale Watch Co., researchers made their third boat trip since mid-November out to-ward Jordan Basin, more than 50 miles south of Mount Desert Island, to conduct a survey of the area to see if large groups of right whales might be present.
Moira Brown, research scientist with the New England Aquarium in Boston, said last week that winter congregations of whales in the area of Jordan Basin first were documented by scientists in 2004. Two years ago, in December 2008, two aerial surveys conducted by the federal National Oceanic and Atmospheric Administra-tion each revealed more than 40 whales gathered together in the basin.
According to whale researchers, only about 450 right whales are believed to remain in the North Atlantic today.
Most right whale calves are born in January or February, Brown said, and the gestation period is between 12 and 13 months. December, she said, is when these animals are believed to mate, and finding out where they do so is an important factor in protecting right whales so they don’t go extinct.
“That’s why we’re so interested in [finding whales at] this time of year,” Brown said.
If scientists establish that there is a winter mating ground in the Gulf of Maine, she said, it could lead to mandated protections such as requirements for ships to avoid the area or to slow their speeds when they travel through it.
About a dozen people, including volunteers and researchers with the aquarium and with the Canadian Whale Institute, saw 11 right whales during a Nov. 16 boat survey and seven right whales on Nov. 30, according to Brown.
On Dec. 18, survey participants saw only five right whales as the catamaran was transecting the southwest corner of Jordan Basin and an area west of it. Brown said that approximately 30 to 40 miles farther west, however, in the vicinity of Cashes Ledge, a simultaneous NOAA aerial survey detected 28 right whales, 15 of which were involved in a social active group. A social active group, or SAG, is a sort of multiwhale scrum at the surface that researchers believe is part of the whales’ courtship and mating process.
The low number of right whales seen during the Dec. 18 boat survey, and the fact that 28 whales were seen dozens of miles away, is not a sign that the theory that Jordan Basin is a mating ground is incorrect, Brown said.
“It think this [mating] area might have been quite a bit larger than we had suspected,” Brown said.
One significant factor that is believed to help determine where whales congregate is food.
Tony LaCasse, media relations director for the New England Aquarium, said last week that the number of whales found this past summer in the Bay of Fundy was unusually low — most likely because higher-than-normal water temperatures were affecting the abundance of plankton in the water.
It was the lowest plankton level in 30 years, LaCasse said.
According to Brown, the number of individual whales documented in the Bay of Fundy this past summer was 55, “well below” the number of individual right whales documented in the bay in 2009.
“The animals just seem scattered,” she said.
LaCasse said that if plankton counts are low off Maine and eastern Canada, it could affect the entire marine food chain in the region. Nutrients bloom most often where cold water mixes with warmer water, particularly over shallow plateaus, he said. The Gulf of Maine, where warmer waters from the south mingle with cooler waters from the Arctic as they wash over and around Georges Bank, usually has high nutrient levels that help attract marine life, he said.
LaCasse said researchers also are interested in finding out if Jordan Basin may be a frequent winter feeding area for right whales. Observing such behavior in the winter can be difficult, however, because plankton often is lower in the water column in the colder months. Frequent bad weather and shorter daylight hours also make winter boat and aerial surveys more difficult, he said.
That hasn’t been observed yet, LaCasse said of feeding behavior in Jordan Basin.
According to Zach Klyver, a naturalist with Bar Harbor Whale Watch Co., the recent boat surveys provide biologists with useful data despite the relative lack of right whale sightings. People on the Dec. 18 outing also saw 13 finback whales, five minke whales, and an estimated 500 white-sided dolphins, he said. Many seabirds also were observed and documented during the 12-hour journey.
Klyver said that the whale watch company, owned by international resort firm Ocean Properties Ltd., wants to help researchers and the general public learn more about right whales. Knowing where whales congregate would be useful to fishermen who want to help make sure whales don’t get tangled in their gear.
In 2009, federal regulators mandated that lobster fishermen who set traps outside a boundary line roughly 3 miles from shore had to use sinking, and more expensive, lines on their traps to help reduce whale entanglements.
“The fact that they’re here in the winter right off the coast of Maine is amazing,” Klyver said of the whales. “My hoping is that having more info will help fishermen, too.”
Brown said that researchers hope to make a fourth trip out toward Jordan Basin sometime between Jan. 3 and 20, weather permitting. The trips have been funded by the U.S. Marine Mammal Commission, Canadian Wildlife Federation and TD Bank, with additional donations from Ocean Properties, she said.
Whether the research program continues next winter, she said, depends on if researchers can secure additional grants and donors.
“I’m writing [funding] proposals,” Brown said.