Posts by Rachel Kaplan

Putting Your Best Tusk Forward: Narwhals and Climate Research

Posted by on Jun 20, 2017 in All Posts, Featured Posts, Science | 0 comments

Putting Your Best Tusk Forward: Narwhals and Climate Research

Spread the News:ShareIn 1576, Queen Elizabeth I paid the equivalent of half a million dollars for a unicorn horn, which she believed could neutralize poison. Of course, it wasn’t a unicorn horn at all, but a narwhal tusk, remarkable in its own right. Today, over 440 years later, narwhals continue to surprise and attract attention. A recent paper in Biology Letters by Kristin Laidre et al. examined narwhal visits to glacial fronts in West Greenland. “We don’t fully understand the relation between narwhals and glaciers,” professor Mads Heide-Jørgensen of the Greenland Institute of Natural Resources told GlacierHub. Laidre added, “Narwhals in places like the Canadian Arctic, for example, have limited access to glacial habitat. However, in Greenland, most narwhals are close to glaciers in summer because Greenland is so glaciated, and there are glaciers along the entire coastline.” It has long been observed that narwhals visit glacial fronts in the summer and autumn, but it is unknown why they seek out this habitat. “Glaciers are productive regions,” commented Laidre. “They attract prey, there’s upwelling and nutrient cycling, and sometimes even osmotic shock to small invertebrates which attracts fish… We hope future studies will help us understand this, but we don’t know exactly why they go there.” Belugas, the “sister species” to the narwhal, also favor freshwater habitat in the summer, seeking out shallow water estuaries. To begin answering this question, Laidre took a novel approach, forming an international, cross-disciplinary team that included scientists from the U.S., Denmark, and the U.K. “The idea was to get biologists and glaciologists to collaborate and share data in an interdisciplinary way,” Laidre said. The team evaluated which glacial characteristics draw narwhals by collecting data from 15 satellite-tagged whales and following their movements through the fjords of Melville Bay in West Greenland. The narwhals demonstrated three preferences: they spent more time at glaciers that discharge a fresher, rather than siltier melt; they preferred slower-flowing glaciers, which are more stable and calve less; and they favored thicker glacial fronts, perhaps because they maximize access to freshwater. Sea ice also provides important habitat for narwhals. “All narwhal populations winter, and some even summer, in dense sea ice concentrations,” said Heide-Jørgensen. In summer, narwhals spend time in the high Arctic where ice has receded, and in fall, the ocean freezes solid, pushing the narwhals away from shore, Laidre explained. “They swim away from the forming ice and move offshore, where they overwinter in dense ice cover with cracks so they can breathe. Narwhals are highly associated with sea ice, perhaps the most of all whales,” he said. Heide-Jørgensen indicated that narwhals will seek out the sea ice when it decreases in coverage rather than wintering in open water. “Reduction of sea ice therefore implies a reduction in habitat, and this will again introduce a reduction in prey base or carrying capacity. In short, less sea ice means less narwhal habitat and eventually less narwhals,” he said. Laidre agreed that “changes in sea ice and the marine ecosystem will likely be the most important factor” to the future of narwhals as climate changes. Since 1979, sea ice freeze-up has occurred almost a month later in Baffin Bay and Melville Bay, where this study took place, and glaciers, of course, are retreating. But far from being simple victims of global warming, narwhals can aid in the collection of data that can help mitigate climate change. In 2005 and 2007, Laidre took advantage of narwhals’ capacity for deep dives and tendency to winter in sea ice, outfitting narwhals with temperature and depth sensors. Narwhals regularly dive over 1,700 meters to...

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Roundup: A Shrinking Lake, a Deepening Lake, and Ice below Sea Level

Posted by on Jun 19, 2017 in All Posts, Featured Posts, News, Roundup, Science | 0 comments

Roundup: A Shrinking Lake, a Deepening Lake, and Ice below Sea Level

Spread the News:ShareGlacial Retreat Shrinks Yukon’s Largest Lake From CBC News: “Kluane MLA Wade Istchenko says receding water levels on Kluane Lake are posing a problem for his constituents — and he wants the government to respond. The lake level first dropped last year, after the Kaskawulsh Glacier retreated so much that its meltwater abruptly switched direction, away from Kluane Lake. Researchers have blamed climate change for the geologic phenomenon referred to as ‘river piracy’.” You can read more about how Istchenko proposes the legislature respond here.   Spillway Lake in Nepal Deepens From Water: “Since the 1950s, many debris-covered glaciers in the Nepalese Himalaya have developed large terminal moraine-dammed supraglacial lakes, which grow through expansion and deepening on the surface of a glacier. As temperatures continue to rise and lakes continue to grow in area and volume, they pose a flooding risk to the Sherpa villages down-valley.” Learn more about how the Ngozumpa Glacier’s terminal lake is growing here.   Melting an Ice Sheet from Below From Nature: “Because the East Antarctic Ice Sheet seems so cold and isolated, researchers thought that it had been stable in the past and was unlikely to change in the future — a stark contrast to the much smaller West Antarctic Ice Sheet, which has raised alarms because many of its glaciers are rapidly retreating. In the past few years, however, “almost everything we thought we knew about East Antarctica has turned out to be wrong”, says Tas van Ommen, a glaciologist at the Australian Antarctic Division in Kingston, near Hobart. By flying across the continent on planes with instruments that probe beneath the ice, his team found that a large fraction of East Antarctica is well below sea level, which makes it more vulnerable to the warming ocean than previously thought. The researchers also uncovered clues that the massive Totten glacier, which holds about as much ice as West Antarctica, has repeatedly shrunk and grown in the past — another sign that it could retreat in the future.” Read more about uncertainty in the East Antarctic here.     Spread the...

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Abuzz with Opportunity: Drone Research in the Antarctic

Posted by on Jun 15, 2017 in All Posts, Featured Posts, Science | 0 comments

Abuzz with Opportunity: Drone Research in the Antarctic

Spread the News:ShareSummer in the Western Antarctic Peninsula brings long days, short nights, and a burst of life and activity. Penguins attend to the drama of colony life, seals alternate between hunting and sunning on ice flows, and humpback whales swim by, admired by tourists from the decks of cruise ships. The warmth of the summer sun causes glaciers to calve, creating new icebergs. Now, there’s a new kid on the block— hovering above the glacial landscapes and wildlife, you can sometimes spot an unmanned aerial vehicle (UAV), or drone, helping researchers study animals in new ways. A recent Cambridge University Press publication by David Leary assessed the regulatory response to UAVs by the Antarctic scientific and tourism communities. The Antarctic is new territory for drone researchers and forbidden ground for tourists. In 2014, as both recreation and scientific drone usage in the United States were ramping up, the National Science Foundation prohibited research drones until the agency could address environmental and safety concerns and establish a set of best practices for deployment in Antarctica. The International Association of Antarctic Tour Operators (IAATO) banned drones for the same reasons during the 2015/16 and 2016/17 seasons. Nations outside the U.S. have been leading the charge on Antarctic drone research, and the initial results have been promising. A 2014 project by the Japanese National Institute of Polar Research used UAVs to take aerial photos and magnetic data of Deception and Livingston Islands, collecting data on glacial recession with much lower risk than comes with traditional, manned aircraft. A study by the Warsaw University of Technology and Norwegian National Center for Research and Development outfitted drones with remote sensing technology to gather baseline data on glacial retreat, flora distribution, and whale and seal populations. Professor David Johnston of the Duke University Marine Lab is at the forefront of U.S.-based Antarctic drone research. After receiving a small facility grant from NSF about two years ago, Johnston used the funds to renovate an old building, purchase aircraft and computing infrastructure, and start dreaming up new research questions involving drones. The technology is “changing faster than anything I’ve ever seen,” marveled Johnston. “In the last couple of years, our aircraft can now fly twice as long, the resolution is almost double, and the cost has come way down.” Johnston’s team was first able to fly their aircraft around the Western Antarctic Peninsula on a research cruise in January and February 2017, and they hit the skies running. The team collected footage that allowed them to efficiently count seals and penguins, used photogrammetry techniques to measure humpback whale size, and photographed the process of “bubble netting,” a foraging technique in which the whales work together to concentrate prey into high-density aggregations. “That was one of the more epic things we were able to capture on the trip,” said Johnston. “We can study the timing of bubble burst, the width of the nets, and translate beautiful images into deeply quantitative data.” Johnston is working to demonstrate the value of this technology to research partners in the Palmer Long-Term Ecological Research Station. He anticipates a future of on-demand aerial surveys and remote sensing, and a huge range of applications that include looking at vegetation growth and using a thermal camera to study glacial ground flow. Though there has been concern about UAVs disturbing animals, Johnston believes they are actually among the best practices for wildlife research. “Whales, seals, and sea turtles don’t know drones are there— We can do our measurements in ways that are less risky and noisy. It’s better than sending people through penguin colonies, approaching...

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Photo Friday: A look at the 2017 Denali Mountaineering Season

Posted by on Jun 9, 2017 in All Posts, Featured Posts, Images, Sports | 0 comments

Photo Friday: A look at the 2017 Denali Mountaineering Season

Spread the News:ShareIt’s summer in Alaska, and for some intrepid adventurers, that means it’s mountaineering season on Denali, the iconic peak whose name means “The High One” in the Koyukon Athabascan language. According to the Denali National Park Service mountaineering blog, Denali Dispatches, there are currently 520 climbers attempting the highest peak in North America. 142 climbers have already reached the summit this season, a 34 percent success rate. This week held some excitement for the Park Service, which on June 5th responded to two simultaneous medical incidents on the Kahiltna Glacier. One climber, suffering from “acute abdominal illness,” was assessed and helped by park personnel to Kahiltna Glacier Base Camp. More dramatically, another climber was un-roped when he fell forty feet into a crevasse on the West Buttress route, and became wedged in the ice. Rangers arrived at the accident site at 4 a.m., and after nearly twelve hours of chipping away ice with power tools, they were finally able to extract the injured and hypothermic climber, who was hastily evacuated to the hospital in Fairbanks.             Spread the...

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Cruise Ships Cause Murrelets to Demur: Management and Tourism in Glacier Bay

Posted by on Jun 8, 2017 in All Posts, Featured Posts, Policy and Economics, Science | 1 comment

Cruise Ships Cause Murrelets to Demur: Management and Tourism in Glacier Bay

Spread the News:ShareWhen the U.S. National Park Service was established by the Organic Act of 1916, just over 100 years ago, it was given two mandates: to protect the natural resources in its parks, while also allowing for enjoyment of those resources. Sometimes, these mandates conflict. In a May 2017 paper in PLOS One, Timothy Marcella and his co-authors describe one such case. The paper shows that cruise ship traffic in Alaska’s Glacier Bay National Park and Preserve disturbs two rare seabird species, Kittlitz’s and marbled murrelets. Glacier Bay National Park and Preserve, a 3.3 million acre region of water and land in Southeast Alaska’s Inside Passage, is characterized by vast tidewater glaciers and the landscape created as they recede, a succession from bare rock to mature spruce and hemlock forests. The Park provides crucial habitat for Kittlitz’s murrelets, which nest on the ground in deglaciated terrain, drawn to tidewater glaciers and the marine invertebrates and fish that live in glacial outflow. Up to 37 percent of the global population of Kittlitz’s murrelets visits Glacier Bay in the spring and summer, and as much as 95 percent breeds in Alaska, as the authors indicate. Closely related to Kittlitz’s murrelets, marbled murrelets nest in old-growth forests, crucial habitat preserved by the Park. Wildlife observers poised on the bows of cruise ships found that, in areas of the cruise track dominated by Kittlitz’s murrelets, 61 percent of all murrelets approached within 850 meters by a cruise ship showed signs of disturbance. For a seabird, this means changing from a “loafing” behavior like sleeping, preening or swimming, to either taking flight or diving. In areas of the park where marbled murrelets were more prevalent, the effect was even greater— 71 percent of birds dove or flew away. However, Scott Gende, project lead and co-author of the PLOS One paper, believes these diving and flushing behaviors aren’t necessarily harmful. Speaking from Juneau, where he and his team prepared for a cruise to study disturbance in harbor seal pups, Gende pointed out that long-term monitoring of both species suggests that their populations within Glacier Bay are stable. “If the murrelets are living on the energetic margin (having only sufficient resources for survival, and no more), one more dive could make a difference— disturbance events could equate to a population effect. If we assume that the stable numbers of murrelets over the years is reflective of their ability to forage and breed successfully in Glacier Bay, it’s not likely that the disturbance events are so egregious that it’s causing the murrelets to have lower reproductive success or survival rates,” Gende told GlacierHub. If the murrelets’ populations are healthy, is disturbing them inherently a problem? Gende doesn’t think so. “Parks are for people,” he quipped, and noted it is far easier to measure impact to a natural resource, like seabirds, than to measure the positive effect of people on the ship experiencing that resource. “People are moved by Glacier Bay, seeing wildlife— bears on the beach, whales, the scenic wilderness. That can have a profound impact on their experience of national parks,” he said. Positive experiences in national parks are important not just to individuals, but to the protection and longevity of the national park system itself, which relies on public and congressional support. “Over the years I’ve been doing this research,” Gende reflected, “I’ve talked to hundreds of people, and I’m convinced the experience they have pays dividends to recognizing values of having national parks and these protected areas in general.” In addition, the cruise ship presence in Glacier Bay directly creates an opportunity for...

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