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Text-only version for easy printing Encounters with Leviathan "Save the Whales" is more than a slogan for David Potter '74 In early June, Right Whale #1102 had a very bad day. While trolling the ocean surface for a zooplankton snack, mouth agape, 1102 snagged a fishing buoy line. The 50-foot 60-ton animal spun and thrashed, trying to break free. The line tightened around his snout, cutting into his hide, slicing through his blubber, and cinching the feathery threads of his baleen. A whale-rescue crew from the Center for Coastal Studies of Provincetown, Mass., motored out to the whale in a small inflatable boat to try to cut the line. Overhead, inside a National Marine Fisheries Service (NMFS) plane, David Potter '74 tracked the efforts below. His office, the Protected Species Branch of the NMFS, commissions the rescue crew to help tangled whales. Most of the five or six calls a summer end in success. Eleven-02 wasn't so lucky. The media named him Churchill. For weeks he was a fixture in the local and national news as rescuers struggled to remove the line set deep in his jaw. His health deteriorated as an infection turned his sleek black skin a pale white, which began to slough off in chunks. Over the next few weeks, as the crew launched repeated missions to untangle 1102, including a first-ever attempt at sedating so large an animal, Potter hoped for some sign that the animal might survive. Churchill swam north to Canada and rescuers followed, battling choppy seas and rigging massive tranquilizer guns. People talked about Churchill at office watercoolers. Others prayed, psychics weighed in, and a homeopathic doctor suggested giving Churchill massive doses of valerian root. Despite all efforts, 1102 probably won't make it. The open wound caused by the fishing line created a systemic infection that he may not survive. Right whales that die eventually wash up somewhere on the North Atlantic coast. That's when Potter rolls up his sleeves. He'll study Churchill's necropsy looking for clues to help him save the most endangered large whale left on the planet. The North Atlantic right whale, eubalaena glacialis,, is the rarest of the large whales in the world. Current estimates hold that no more than 350 survive. "Given this small number, our knowledge about them is pathetic," says Potter, a scientist with the Protected Species Branch of the National Oceanic and Atmospheric Administration (NOAA) in Woods Hole, Massachusetts. "We may find that they are already doomed to extinction. They may be too close genetically already. Too many cousins marrying cousins," he says wistfully. During a pilot study of the right whale last year, Potter, Capt. Wayne Perryman, and two assistants photographed more than 100 right whales from a research aircraft. They tracked the animals from their summer feeding grounds off the coasts of Maine and Nova Scotia to their winter waters off the coasts of Florida and Georgia--an active shipping area. "We recorded 30 recent births," says Potter, a positive sign. "But we had no idea where the other 200 North Atlantic right whales were. No idea at all." Until recently, there was little money in the NOAA budget for whale studies. In 1998, Potter's branch formed a large-whale research program and started to identify some of the threats. Congress then earmarked funds for Potter's three-year study of the right whale beginning in August of this year. With the aid of advanced technical equipment, he will systematically catalog the population, learn about the animals' behavior and seek ways to protect them. Right whales frequently spend time lying on the surface and thus are vulnerable to collisions with ships. "We estimate that at least 60 percent of the human-induced mortalities in right whales are caused by ship strikes," says Potter. More than half the animals viewed in Potter's pilot study show some evidence of having been either struck (some have visible propeller scars on their backs) or entangled in nets. In a separate study, Potter has begun working with Dr. James Miller from the University of Rhode Island to modify sonar used by the Navy to block out biological noise under the ocean surface in its search for enemy submarines. Those are the very sounds Miller and Potter were seeking. Using a phased array of sonar devices, they engineered a system that enables them to "see" (through the systematic deflection of sound waves) large objects in the water. The sonar records the whales as blips on a computer screen, and can detect an animal up to a kilometer away. Once the sonar has been thoroughly tested and tweaked, it can be easily mounted on any ship. The benefits are two-fold. "With the sonar, we can study whales' behavior. We can see how long they stay on the surface, how deep they dive, their patterns of movement--all without harassing them. For the most part, they won't even know we're there," explains Potter. But the sonar also enables a ship to "see" a whale ahead, and alter course to prevent collision. "We don't kid ourselves. Shipping companies aren't going to buy $40,000 sonar systems to help us save the whales," Potter says, "but they will use it to prevent hitting other floating objects." The ocean is littered with empty containers that have fallen off ships, he explains. "They float just under the surface, making them a real nuisance. When a ship hits one, it causes hundreds of thousands of dollars worth of damage. With our sonar, ships can avoid collisions of all kinds, including ones with right whales," says Potter. The objective of Potter's three-year study is cataloging the entire North Atlantic right whale population. Unique to the right whale are callosities--horny growths on and around their heads, blowhole, rostrum, eyes and jaw. These act like fingerprints helping researchers identify each animal individually. Potter's photogrammetry study will be the first consistent census of the species. Again using surplus military equipment, this time from the Air Force, Potter and scientists have modified a reconnaissance camera to photograph whales from the sky. They've outfitted a De Havilland Twin Otter airplane (formerly a Canadian bush plane) with bubble windows for observation. A hole in its belly holds the camera. Using a radar altimeter, the crew can calculate an animal's measurements from above to within a centimeter. "Having a baseline set of measurements allows us to see how the whales change over time, for instance how nursing affects a mother's size and weight. We should be able to tell a healthy calf from a sickly one, simply given an average growth rate," he says. For a month this past August, Potter and researchers made 15 flights out of Bar Harbor, Maine, to photograph the whales. Potter will spend the fall and winter reading the films. He uses special light tables with microscopes connected to booms to review every animal in every frame of a five-inch film format. He will record length, fluke width, and girth for every animal as well as information on baby whales' growth rates. Next summer, the team will renew its air and sea observations. Meanwhile, Potter will be studying the whales' behavior in the water using the sonar. Hopefully answers will turn up along the way. "We might find, for instance, that the whales --like Churchill-- are only snagging on the top line of fishing buoys. Perhaps there's a way to modify the lines in the heavily trafficked feeding grounds to prevent snags. At this point, we know so little, it's hard to guess what clues we might find." It's precisely this kind of mystery and problem-solving that has kept Potter enchanted by ocean studies for 27 years with the National Marine Fisheries Service (NMFS) at NOAA. "He was a long-haired hippie, with hip-hugging bell-bottoms," remembers David Potter's wife, Christina "Tina" Hoene '74, about the moment she first met her future husband. He was hitchhiking south on I-93 in New Hampshire, and her mother pulled over to give him a lift. Both were students at Plymouth State College in the mid-'70s, and both transferred to UNH, Tina for nursing, Potter for science. After Tina graduated, they married and moved to Woods Hole. "My high school career was less than stellar," admits Potter. "But at PSC, I discovered science: biology, zoology, botany. ... I could sit through an invertebrate zoology lecture and listen, while taking very few notes, and retain everything." He ran out of science courses at PSC and headed for Durham where he connected with professor Larry Harris, a lifelong friend and mentor. As an undergraduate, Potter became a SCUBA diver and collected benthic samples (ocean-bottom-dwelling invertebrates--worms, clams, and the like) for Harris' various research projects. After graduation, Potter worked for several months in Portsmouth, N.H., for Normandeau Associates, but his sights were set on Woods Hole. The community houses four scientific institutions--the National Marine Fisheries Service, the Marine Biological Laboratory, the Woods Hole Oceanographic Institute and the U.S. Geological Survey--making it the epicenter of marine science in America and the world. "He rode down there on his Yamaha motorcycle and started knocking on doors until they hired him," Tina says. Since 1974, Potter has been a marine scientist with the NMFS. The federal government passed legislation in 1972 called the Marine Mammal Protection Act designed to protect and manage marine mammals and their products. NMFS was given the responsibility of enforcement. Potter's branch at the NMFS determines the population size of every species of whale, dolphin, porpoise and seal from Hatteras, N.C., to the Canadian border out to the 200-mile limit. Their findings help guide resource management. "I have done everything from driving research submarines on the bottom of the ocean to flying aircraft in search of whales. ... Tina actually calls this my 'Peter Pan' job because I never had to grow up and get a 'real' job," he says. Potter has been involved in a variety of studies over the years. His first project was developing a sub-sea habitat to study herring eggs on the ocean floor. Such a habitat was necessary because eggs and larvae are very delicate and not easily moved. Also, on the ocean floor, the eggs are under three atmospheres of pressure, which is hard to duplicate in an onshore lab. Since the herring were so endangered, the scientists needed to observe them in their natural environment to study the role of predators, currents and weather in their survival. Potter has cataloged the aftermath of over-fishing ("I've seen spots on the ocean floor off George's Bank that look like a well-graded gravel parking lot"), and he's spent weeks at a time on a research vessel at sea researching cod and haddock populations. Once, when surveying whales from a helicopter in the Great South Channel, the pilot had to perform an emergency rescue, pulling a fisherman to safety from a burning boat. He's led seal "rodeos" to round up, count and radio-tag the animals. He's "shot" dolphins ("I used to give a slide-show presentation called 'The Man Who Shot Dolphins' about how we'd take a plug of the animal with a special crossbow then perform a biopsy for study"). Chances are, if it swims, crawls, floats or breaches in the North Atlantic Ocean, Potter can tell you all about it. One of his greatest successes came during his tenure as acting director of the Protected Species Branch of NOAA during the mid-1990s. At the time, fishermen were accidentally netting 2,000 harbor porpoise a year, a significant blow to a population of just 56,000 animals. Through cooperative efforts with the industry, Potter and his team came up with a pinging device to hook on fishing nets that used the animal's own instincts to deter it from danger. Now fewer than 400 porpoise get caught a year, well under a sustainable number for the species. His curiosity about the natural world around him extends to his home and family. The Potter household in Falmouth, just north of Woods Hole, includes plenty of wildlife, including four teenagers, a parakeet, five horses (one wild mustang rescued through the Bureau of Land Management), dogs, cats, and a 70-gallon saltwater fish tank with live coral. Both at work and at home Potter respects an animal's right not to be needlessly harassed by humans even in the name of doing good. This is the delicate balance that informs his work every day. Potter and his colleagues jokingly refer to whales as "charismatic megafauna" for their ability to arouse affection in humans. "Cetaceans are loved the world over," explains Potter. "Even I'm not immune. I've been watching these creatures for 27 years. If a pod of dolphins or a sea turtle comes into view, I'll keep on working. But a whale? I always stop to see it." One sighting stands out above all the others. Potter tells of following a pod of killer whales off the coast of Alaska a few years ago. "They're the apex predator on the planet. It is fascinating to watch them work as a group." The research ship cruised along, and white-sided dolphins came by to frolic in the bow wake. At the first sight of the dolphins, the killer whales dove in complete synchronicity, disappearing under the boat. "Then a female came out of the water like a Poseidon missile," remembers Potter, "with a dolphin in her mouth. She smacked it on the water and let the stunned animal swim away, making it easy prey for two juvenile whales in the pod. She was teaching them how to hunt." Potter's small office looks out over what is actually Woods Hole: a small channel between islands leading into the harbor. Sailboats glide by, ferries bring passengers to and from Martha's Vineyard, and sea roses are a riot of pink at water's edge. A stuffed whale mobile bobs in the breeze. He talks on the phone with the Provincetown crew about the welfare of Churchill. Canadian officials are working with them to organize another attempt at sedating the animal and removing the imbedded fishing line. "Every right whale we lose is a huge blow," says Potter. "In many ways our time is running out." Potter is sympathetic to Churchill's plight, but he knows that to prevent more deaths, he must focus on the right whale population as a whole. He may not be able to save 1102, but he can utilize advanced technology to study the whales and look for answers. And with a little luck, he can find a way to save the North Atlantic right whale from extinction. ~ Carol Connare '88 is senior associate editor at Yankee magazine. Return to photo version See also: Right Whale Tale |