Aviation
Wrong Turn for Right Whales
For 300 years the northern right whale has been staving off extinction. Now, using airborne observation and high-tech tools, scientists are keeping close tabs on nature’s rarest whale.
By Sydney Horton

Northern Right Whale
(Eubalaena glacialis)
Endangered throughout its range

By the 18th century, after being hunted for 800 years, the right whales of the North Atlantic were near extinction. The current population estimate for the North Atlantic right whale is a mere 300 to 350 individuals in the northern hemisphere—making them the world’s rarest whale species and the most endangered. Today scientists are pursuing these enigmatic leviathans with no less passion than hunters once did, observing and recording the health, habitat, mating, calving, life, and death of each individual.

Since 2002 researchers from the Stellwagen Bank National Marine Sanctuary have manned the Fuijifilm Blimp in order to obtain high-tech, high-performance digital images of right whales as the animals browse their late-spring feeding grounds off the coast of Cape Cod. More routine surveys—once or twice a week year-round, depending on the weather—are conducted via another kind of airborne observation post: inside a DeHavilland Twin Otter fix-winged aircraft during four- to six-hour flight covering the Atlantic from Maine to south of Long Island New York—a vast swath of coastal waters encompassing the population’s entire spring feeding grounds. Using a laptop computer tied into a GPS, and custom-made software, scientists can fix the exact location of the cetaceans, record environmental conditions, and note current fishing and commercial shipping activity. Though right whales have but one predator—killer whales—collisions with ships and entanglements in fishing gear are chief among causes of mortalities for these slow-moving 50-foot-long, 70-ton cetaceans. Lobster and crab pots in particular can be lethal. As many as 40 traps at a time, lashed together by polypropylene rope, can sit on the ocean floor, where they make perfect snares for a feeding baleen whales. (Right whales, like all baleens, have no teeth and are filter feeders, so they swim with open jaws.) When rope from the traps enters their mouth, panic and struggle immediately ensues. All too frequently, even one of the most powerful animals on earth is unable to sever the rope and is drowned.

Courtesy of NOAA Fisheries

Tim Cole, a research fisheries biologist based at the Northeast Fisheries Science Center in Woods Hole, Massachusetts, has worked with right whales since 1992, leading a team of five whose sole objectiveis to locate and document right whales. “When we see one, we break away from our survey line and fly directly over the top to mark their exact position. Then we bank sharply and a photographer leans out of a window in the back, shooting straight down over the whale as it surfaces. When the image appears on our laptop we can see if we need to take another pass over. Individuals can be identified by the white pattern on their heads—‘callosities,’ rough patches of raised skin unique to an animal—like a fingerprint.” Every three months photographs from Cole’s aerial surveys are bundled off to the New England Aquarium in Boston, home of the North Atlantic Right Whale Catalog, which contains 200,000 images of the species, some dating to 1935.

Amy Knowlton, a research scientist with the aquarium who also studies right whales in their summer feeding and mating habitat in the Bay of Fundy, says that during the 1980s and early 1990s the North Atlantic population seemed to be faring pretty well. Then, in the late ’90s, calving rates crashed three years in a row. “Their condition was not good,” says Knowlton. “They had gray peeling skin, and you could tell by a lot of the images they were thinner than usual, and many had skin lesions. Now the situation seems to be improving—the average number of calves per year was about 11, but in recent years there have been 15 to 30 a year.” Still, that’s not enough to overcome the declines of the 1990s. Females over the age of nine calve every three to six years between December through March in the shallows off northern Florida and Georgia.

Each right whale in the catalog is assigned a four-digit number. “The beauty of it is that it’s a long-term project,” Knowlton says, and thus the majority of the North Atlantic population is recorded, and many have thorough life histories. Even the genetic diversity of these whales has been studied to determine whether or not the low numbers are leading to inbreeding. Fortunately it’s become clear to many in scientific research that low genetic diversity is not likely to be a cause of the species’ extinction. But sadly, as Knowlton acknowledges, the catalog includes pictures of mortalities, Since 1986, 56 North Atlantic right whales have died—nearly half were struck by ships, while eight died in fishing gear. During this same period 61 right whales in the population were found to be carrying fishing gear. Although the natural lifespan of the right whales is unknown, it is thought to be at least 30 to 50 years, and is likely much longer. “We have one record of an animal who was at least 75 years old, but she was stuck and killed by a vessel in 1995,” Knowlton says, adding that the team is making a strong effort to locate and tow ashore mortalities for necropsy in order to determine the cause of death.

Mark Baumgartner, a biological oceanographer based at the Woods Hole Oceanographic Institution, takes a different tack with his research. He heads out to sea in a 60-foot vessel equipped with a 15-foot rigid hull inflatable, which he uses to attach tiny transmitters to whales. Since right whales lack a convenient dorsal fin, Baumgartner came up with the idea of attaching a tiny time-depth recorder to the whales by using a suction cup on the end of a long telescoping aluminum pole. He says it’s as simple as driving up to the whale and sticking the suction cup on their backs. “Sometimes they see us approach, but we prefer to catch them unaware. The time-depth recorder is not a complicated device; it gives off a ping and, like a dog whistle, we can’t hear it, and neither, it seems, can the whales. We have buoys with receivers listening for the ping, and if we get a couple of pings, we can compute the position of the whale in real time, even though they dive completely out of view. It lets us get very close to the whales to track their behavior in real time and find out what’s going on in the environment.” When a tagged whale surfaces, Baumgartner approaches with the research vessel and drops instruments overboard that will measure the distribution of the right whales’ prey, copepods—zooplankton called Calanus finmarchicus, which are the size of a rice grain—as well as ocean conditions. When the tags fall off in an hour or two they float and are retrieved, The data tell Baumgartner how the dive of the whales relates to the depth, location, and abundance of their prey. “It’s imperative to understand where the whales go and what they do,” he says. “It’s critical to right whale conservation.”

Courtesy of NOAA Fisheries

All of these studies and many others are paying off in the form of new efforts to protect the North Atlantic right whale from ships and gear and aid in the species’ recovery. Richard Merrick, chief of protected species at the Northeast Fisheries Science Center at Woods Hole, and scientists at the Stellwagen Banks National Marine Sanctuary have identified large areas of the Northeast where the whales congregate, using more than 10,000 right whale sightings between 1960 and 2003. They propose that by making slight modifications to shipping lanes on the approach to Boston Harbor, the risk of collisions between ships and whales could be halved. Though the right whales of the North Atlantic have failed to rebound from centuries of slaughter, Merrick remains hopeful. “Over the long haul we’re generally optimistic about the recovery of these whales,” he says. “Removing threats can only improve their chances of recovery.”

Scott Kraus, a scientist with the New England Aquarium’s right whale project, notes that last year the administration and Congress cut funding for right whale recovery efforts in half. “With that sort of approach to conservation, right whales do not have a good chance. Thus far National Marine Fisheries Service has been unable to dent the number of whale kills,” he cautions, adding that without some significant changes, current population projects have this species going extinct in less than 200 years.

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