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Dispatch 4, George VI Sound
May 1, 2002 / George VI Sound -- With several days spent in sea ice this week, rumbling, crunching and banging became the new music of the icebreaking Nathaniel B. Palmer. In the northern end of George VI sound -- the corridor that separates Alexander Island from the Western Antarctic Peninsula -- the Palmer powered through thick, year-old pack ice, covered with pristine new snow. The horizon disappeared as the clouds, ice, and snowy mountains of Alexander Island blurred together into whiteness. With the boat steadied and the ocean masked, the voyagers might have believed they were on land. But the creviced landscape sometimes rippled as a large swell rolled beneath. And the Palmer often tilted sideways for a long pause as she climbed the ice to crush it with her weight. "It's like the tilt you get when you're on a snowboard," ship's mate Rachelle Pagtalunan explained it. The days are getting shorter, and the night was black as the Palmer made her second rendezvous with the Laurence M. Gould last night. The lonely lights of the two approaching ships illuminated a strip of colliding ice floes; ship's mate John Higdon remarked this was what it must look like to be on top of a giant marshmallow that's starting to crack from heat. The ships got close enough to trade snowballs, supplies, and, briefly, passengers. Seabirds as a biological barometerLeaving Marguerite Bay early this morning, the Palmer steamed through a vast wasteland of new lumpy, slushy "shuga" ice that was dotted with broken ice floes and cakes -- the snow-covered leftovers of last year's ice. "You can see lines in the snow where penguins slid on their bellies and big depressions where seals have been," noted seabird researcher Erik Chapman of the University of Wisconsin. Just as he said this, an ice floe carrying two crabeater seals floated by the port bow. Rolling playfully, the seals seemed undisturbed by the giant Palmer. While the ice tested other scientists' gear and patience, bird surveyors Chapman and Matthew Becker welcomed it. Adelié penguins, one of their focus animals, are chiefly found near ice. Ice brings food up to the surface, "nurses" baby prey that will grow into hardy penguin meals, and gives the penguins a surface to haul out on, Chapman said. Chapman and Becker are mapping the distribution of flying birds and penguins along transects of the Palmer's survey grid. Because birds congregate where food is, they point scientists to biological hotspots. This is especially useful in the winter, when sea life is sparse and hidden. "Sea birds have an extremely well-developed ability to perceive the ocean in ways we can't," Chapman said. "If your goal is to understand the biology of a large area of ocean, you have to use clues like that." The presence of certain species also flags events down the water column. Cape petrels and southern fulmars feed on tiny copepods right on the surface; Antarctic petrels plunge into the water and catch fish below the surface; Penguins dive much deeper, scrounging for krill or fish. During daylight, Chapman and Becker identify and tally all the birds in a precise visual sector -- 300 meters (984 feet) out and 90 degrees wide -- as the ship is moving along its transect. One of the difficulties of counting birds is that the ship picks up followers, birds that are attracted to the boat and circle it for miles. Keeping track of these tagalongs to avoid double counting can be a nuisance. "But it's not as if we started in the Drake Passage and we've just brought along all the birds from Chile, and we've got several thousand of them," Becker said. Unlike in places that allow dumping -- where giant swarms of birds feast on jettisoned trash and fish guts -- the birds eventually drop off, he said. The view from the "bird box"Chapman and Becker observe from the "bird box," a specially designed wooden box securely tied to the wraparound ledge outside the bridge. Big enough to accommodate two or three people, it's open on top for overhead viewing, but blocks the wind below one's shoulders. Apparently, the bird box is often a topic of conversation and good-natured ribbing among SO GLOBEC scientists. "It's taken on a life of its own," Chapman said. Because of its slightly awkward appearance on the pristine bridge, the Palmer crew was reluctant to tie it on last year. Since then, it's actually become a popular spot to take in the views and the sounds of the ocean, but it's still regarded with a dash of levity. Chapman and Becker enjoy the lighthearted banter at the end of the day, but when it comes to their science, they're all business. They believe that their work is an essential complement to traditional oceanographic approaches. "The real strength and power of our work is that it ties everything else together," Chapman said. "It's taken some time for whale and sea-bird and seal biologists to gain acceptance in the oceanographic research world, however," Chapman said. "I think in some places, the impression is: the science is going on down there, and we're just bird watching," Becker added. But, Chapman said, their approach is gaining momentum as oceanographers recognize the clear-cut relationships between sea birds and physical and oceanographic variables. "It's amazing, even just in the course of these [SO GLOBEC] cruises, how far people have come in their thinking and their ability to see the big picture." Certainly, Chapman and Becker have the best vantage point for seeing the big picture. They also have a chance to develop genuine awe for their subject matter. "It's just continually amazing to see how these birds have adapted to such a harsh environment yet diversified as well," Becker said. "It's not like they're all cookie-cutter birds." The birds range from the wandering albatross, which has wings spans of up to 9-feet to the tiny Wilson storm petrel, which is the size of a swallow and patters on the water. "They're incredibly beautiful as well, as unscientific as that sounds," Becker said. Studying - and living - life atop the food chainIn contrast to the Palmer, predator work dominates on the Laurence M. Gould. Brett Pickering and Chris Denker of the Polar Oceans Research Group just returned from an 11-day camping trip on Avian Island, a tiny island south of Adelaide Island, where they were tagging Adelié penguins and collecting diet samples. They'll follow the tagged penguins remotely for several months to learn where they travel and how deep they dive. Pickering and Denker camped in Scott tents and made use of a Chilean refuge, a dilapidated wooden hut, to cook and get out of the wind. Twelve hours from the Gould and at risk of being trapped in ice, Pickering and Denker brought two back-up tents, a man-hauling sled, a Zodiac inflatable boat, generators, and plenty of safety equipment. "It wasn't a normal camping trip," Pickering said. "We probably had close to 1000 pounds worth of stuff." They also had to bring computers, as the satellite tags have to be programmed at the last minute to conserve battery life. To keep the computers from freezing, they stored them in a cooler with hot water bottles and heat packs. There were more than 1000 fur seals, as well as some elephant and weddell seals, covering the tiny island when they first landed. "The first few days the seals didn't know what to think of us. They were a little testy," Pickering said. Pickering and Denker successfully tagged 14 penguins and coaxed several penguins into giving them diet samples. " That means we pump their stomachs full of salt water and turn them upside down, gently," Pickering said. Adeliés mainly eat krill and fish, which Pickering and Denker sorted and counted in the biology lab back on the Gould. "We stink up the lab; everyone hates us in our lab," Pickering joked. The first birds they caught were full of krill, nearly 300 grams (10.5 ounces), Pickering said. "It's like a plateful, it really is. More than I'd want to eat of krill." Pickering, along with the other voyagers on the Gould, did eat krill when the Gould's cooks offered krill cakes (like crab cakes) one night. "They weren't bad," said seal scientist Jen Burns of the University of Alaska, Anchorage. "The krill frittata last year was pretty bad, however." Back on the Palmer, not missing the krill feast at all, Chapman and Becker were enjoying another peaceful day in the bird box. "On a good ice day, this is the best place in the house," Becker said. See also: Sidebar - Listening for Echoes from Krill
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