Being COY

April 21, 2010

Polar bear cubs captured, inspected, and released by Hank Harlow's research team. Photo: John Whiteman

The Bears of Summer is back–that’s John Whiteman’s contribution to a collection of polar research dispatches called Ice Stories maintained by the San Francisco Exploratorium. Whiteman, a PhD student in the University of Wyoming’s Program in Ecology, has returned to Kaktovik on Alaska’s north coast for early spring fieldwork.  He’s part of Hank Harlow’s polar bear physiology study, an NSF-funded research project that aims to understand to what extent warmer summer temps–and attendant changes in sea-ice coverage–may impact polar bears who use the ice as a hunting platform. The Harlow team has been capturing, examining, tagging and releasing bears early and late in the growing season since 2008 to find out if they are successfully feeding during the summer, and if not, how they may be using their own body’s resources (mainly fat) for sustenance.

In his latest post, Whiteman writes about examining a gigantic male, the largest bear he’s ever handled. He also comments on the number of COYs he’s seeing–“COYs” being cubs born around January. The above three are taking a snooze on their bear mama while waiting for  a short-lasting dose of anesthesia to wear off.

So far, the team has had some success in recapturing bears tagged last year and in capturing new ones as well; this is particularly good news given that last fall’s capture and study period was hampered by poor ice conditions that prevented the researchers from safely reaching the bears.

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Polar Bear Encounters on Baffin Island

February 1, 2010

On the hunt for clues to past climate, he found polar bears—and they almost found him.

Before the threat of polar bears sent them into cabins, graduate students Kurt Refsnider and Chance Anderson camped out on Baffin Island in tents during summer field work. All photos: Kurt Refsnider

Research Adventures

When University of Colorado PhD student Kurt Refsnider headed north last summer to collect samples for Gifford Miller’s NSF-funded paleoclimate study, he knew what to expect. He’d already spent parts of two summers exploring the remote, wind-swept reaches of Baffin Island in Canada’s High Arctic, searching for evidence of ancient glacial movement.

He knew that a researcher’s best-laid plans were subject to out-of-nowhere storms or shuffling helicopter schedules.  So the first few weeks of the trip he made in 2009 along with graduate student Chance Anderson proceeded largely as expected (if not exactly as planned). Outfitted with tent-camping gear and their sampling equipment, they were transported to the field by helicopter.

“We flew into Pond Inlet on the northern end of Baffin Island,” Refsnider recalled in a recent email.  “We then were moved into the interior of the island by helicopter and spent several days in a particular area before being moved again to a new site.  Bad weather, which kept the helicopter from reaching us during the last two weeks, forced us to stay days longer than planned at two camps.”

Looking for ancient climate clues at the top of the world.

When the weather cleared, the team moved south by helicopter to the Qivitu region. As planned, locals from the community of Qiqiktarjuak helped with logistics.

“We hired two guides to take us by motorized canoe to the Qivitu Peninsula, and we brought one ATV with us to get around once on the peninsula,” Refsnider wrote.  When they reached their study sites, “We set up a camp there, including a trip-wire alarm system due to the presence of bears in the area.”

It beats walking. Getting a ride from a local in a motorized canoe.

Retracing Ancient Ice Sheet Movement for Clues to Past Climate

Miller’s team is analyzing glacial deposits (rock and sediment samples) for information about how ice sheets formed in ancient times, waxing and waning in response to climate change. A few glacial deposits in the area go back about two million years, a rare commodity in the Arctic. Back in their labs, scientists use a variety of high-tech measurements to extract information about the evolution of the ice sheet.  The information should help them better understand long-term patterns in glacial erosion, test a key hypothesis for the cause of a major shift in global climate cycles that occurred around a million years ago, and lead to improvements in ice sheet models.

In addition to these goals, the team was collecting samples of moss and lichen from beneath the edges of rapidly-disappearing ice caps on the interior of Baffin Island.  These ice caps formed in the past few thousand years in response to climatic cooling.   Due to the cold arctic climate, the ice was frozen to the landscape, leaving the old moss and lichen intact.  Radiocarbon dating of this organic material provides a record of precisely when these ice caps formed, allowing Miller’s team to evaluate both potential causes for and the rapidity of this cooling.

Wild Kingdom

Daily polar bear sightings like the one here drove the researchers into hard-walled cabins at night.

The researchers spent a few nights camping, but daily sightings of polar bears—four or five sightings a day, in fact–convinced them to retreat to plan B: to use small cabins that dot the area owned by locals who use them during hunting trips.

The researchers broke camp and drove the ATV to the cabin, a rudimentary structure with boarded-up windows that nevertheless felt like a safer option than the tent camp.  That’s ironic given what came next.

“The first night there, at one or two in the morning we were awakened by a crash on the wall, which was followed by probably five minutes of clawing, scraping, and pounding on the far end of the weak little structure,” Refsnider wrote.  “We stomped and yelled, trying to scare the bear away, but we must have smelled pretty dang good.  The thought of shooting at the bear through the wall crossed my mind, but then there would be a hole for the bear’s claws to tear at, so I just waited, hoping the interior wall didn’t fail.  Eventually the bear gave up, left the mud room, dug briefly around the back of the cabin, and then apparently wandered off.”

The damage done: a polar bear-destroyed mudroom.

The next day, the team flagged down a passing motor canoe and returned to the safety of Qiqiktarjuak to regroup.

“A few days later,” Refsnider continued, “We spent one night at a guide’s cabin 50 km to the south.  As we approached it up the fiord in the guide’s boat, he noticed the front door had been smashed in.  While no one had been there, a bear had broken down the front door, torn up everything inside the mud room, and then left, again without getting into the main part of the cabin.  Our guide, who had been doing this for 50-plus years, was visibly shaken by this.”

Close Encounters of the Unusual Kind

Though polar bear sightings are common in the area, these close encounters with aggressive bears are not. Refsnider’s advisor, PI Gifford Miller, has spent many seasons working on Baffin Island in the company of polar bears, but none of his stories compare to the events of 2009. The reaction of the community to these events speaks volumes, as well:

“The residents in Qikiqtarjuak were amazed by what was happening.  The sea ice had melted/blown out of the area six-plus weeks earlier than normal, so the bears started coming back onto the land far earlier than normal,” Refsnider explained.  “That means they are much hungrier in late August than normal.  The day after we left, the town put two armed guards on patrol 24 hours a day because of the high number of bears in the area.  This had never been done before.”

The bear encounter wasn’t the only unusual experience the researchers had last summer. They also witnessed dramatic thunderstorms, which “are becoming increasingly common on Baffin Island,” Refsnider said. ”We had five days in a row early in the field season with convective thunderstorms blowing up over the central part of the island, most days with cloud-to-ground lightning!  Inuit are surprised by this, and 30 years ago they heard thunder so rarely that some believed that there was one thunder that slowly circled the globe.”

Back to Baffin

The team will return this summer to Baffin Island to finish the sampling, but with increased precautions to limit their exposure to polar bears.  They will base in Qikiqtarjuak, flying between the village and their sampling sites via helicopter, and returning at the end of the day to the safety of the small community. The helicopter will stay with them at the sampling sites. The research team will be accompanied by local guides who stand watch for bear as the team works.

Refsnider says he’s recently heard from his contacts in the village. In an unprecedented turn of events, the sea ice drifted away in December. This means that it is likely the polar bears will find little sea ice on which to stage their hunt for food again this spring and summer—which may increase the likelihood that they will again approach human settlements to find food.

“We’ll be much better prepared to deal with the potential bear risk with several additional armed guides, a helicopter, and more secure place to spend the nights, but I’d be lying if I said I wasn’t still a bit nervous,” Refsnider admitted.  — Kip Rithner


The Arctic Food Chain: Mercury and Polar Bears

January 26, 2010

A recent study found that polar bears predating 1950 that ate a phytoplankton-based diet have higher concentrations of mercury in their systems than bears that eat diets based from the ice algae food web. Photo: Jerzy Strzelecki

The looming threat of melting sea ice has raised awareness about climate change’s impact on polar bears, an endangered species. Also relevant—and less studied—is how changes to the earth—and melting sea ice—could affect the species’ diet. 

Which may be why a recent study in the December issue of the journal Polar Research that establishes two different primary food webs for polar bears and documents surprisingly higher mercury levels in bears that eat from one specific web garnered interest from both the scientific community and science journalists. 

Mercury concentrations can be poisonous to humans and other members of the food chain; currently scientists do not know what levels of mercury are dangerous to polar bears. 

(Note: mercury is not a greenhouse gas, nor is it associated directly with global warming. However, high concentrations of mercury in polar bears is significant to scientists for complex reasons outlined below.) 

Diet Details 

 The study confirmed that polar bears got their food from two primary food webs: 

Phytoplankton-based, which begins with single-celled plants inhabiting the top layer of the ocean 

Ice algae-based, which begins with microscopic plants living within and below the sea ice 

The research went further, analyzing mercury concentrations in the bears’ fur. 

They found that polar bears chowing down on the phytoplankton-based food chain, which originates in the open ocean in the absence of sea ice, had greater concentrations of mercury in their bodies than bears whose diet traced back to the ice algae. 

Dr. Joel Blum, principal investigator, collects snow samples to test for mercury concentrations near Barrow, AK. Photo: Joel Blum

Mercury Investigations 

One of the study’s authors, Joel Blum, the John D MacArthur Professor of Geological Sciences, and Professor of Ecology at the University of Michigan, said the findings are significant as scientists strive to learn more about mercury, an inorganic element whose presence in the atmosphere has tripled since the industrial revolution. 

“Very little is known about how mercury moves around the globe,” said Blum. “But we know humans have increased the amount of mercury in the environment.” 

Mercury can stay in the atmosphere for up to a year and travel to far reaches of the globe, and scientists have documented a considerable amount of mercury deposited in the Arctic. Studying the bears provides important background data on earlier mercury levels, Blum said. 

Factory emissions are a major source of mercury pollution. Photo: courtesy Air Resources Laboratory, NOAA

Museum Bears 

Blum and his colleagues analyzed mercury concentrations in polar bears that predated 1950, before the major influx of mercury from coal-burning power plants and other industrial activities that send mercury into the atmosphere. 

Specifically, they analyzed the late-19th- and early-20th-century polar bear hair for the chemical signatures of nitrogen isotopes, carbon isotopes, and mercury concentrations, looking back in time to a period before man-caused mercury emissions escalated. 

“We know that due to human inputs mercury distribution in the Arctic is currently heterogeneous (multi-faceted and complex), so we decided to take a step back and understand the fundamental processes, pre-1950,” said Blum. 

Phytoplankton Diets = High Mercury Concentrations 

 The discovery that bears that eat on the phytoplankton food chain have significantly higher mercury concentrations suggests that as sea ice melts and bears eat more phytoplankton-based diets, their mercury concentrations could increase, said Blum. 

Moving Through The Food Web 

 And, he added, if concentrations of mercury are increasing in polar bears, which are at the top of the food chain, “this is an indication that they are also increasing lower in the arctic food chain.” 

That means human populations that rely on subsistence hunting could also be experiencing an increase of mercury exposure as well. 

How Mercury Becomes Poison 

 Relatively harmless in its inorganic state, mercury becomes extremely poisonous to humans when it is converted into methylmercury and passed up the food chain. 

Mercury in its methylated state is considered by many to be “public enemy number one,” said Blum. Its prevalence in the Arctic and potential to spread through the food chain is a very real concern and could be exacerbated by climate change. 

Recent discoveries about mercury’s biochemical properties have unlocked mysteries about the element and enabled scientists to probe deeper into the question of how a relatively inert element (mercury) can transform into a menacing poison. 

Scientists know that at times there can be extremely high concentrations of mercury in the Arctic snow pack and are working to understand where it is coming from and what unique chemical reactions take place in the Arctic that lead to rapid deposition of mercury from the atmosphere to the snowpack. 

Next Steps 

  

Sunrise on the flats near Barrow. Blum and his colleagues hope to better understand how mercury travels to and deposits in the Arctic. Photo: Joel Blum

Now that his team better understands the Arctic food web, pre-1950, the logical next step would be to examine mercury levels and nitrogen and carbon isotopes in bears from 1950 to present day, he said. 

In addition, much remains to be understood regarding mercury in the Arctic. Specifically, scientists want to better understand where it comes from, how it travels to northern latitudes, what mechanisms cause it to be deposited, and where it is converted to methylmercury. 

“We want to better understand what’s going on in the arctic mercury cycle, to see if we can help mitigate the problem,” said Blum.  —Rachel Walker


In The News

January 8, 2010

Sea Ice Loss Impacts Polar Bear Habitat

Data from a long-term study finds more polar bears in open water or on land, likely as a result of diminishing sea ice. Photo: National Snow and Ice Data Center

Science Daily reports that a long-term study from 1979 to 2005 shows that polar bears today are found more frequently on land and open water than on ice in the fall, increasing the opportunity for human/bear interactions. Published in the December issue of Arctic, the journal of the Arctic Institute of North America, the study documents significant polar bear habitat changes in response to differing ice conditions. Between 1979 and 1987, 12 percent of bear sightings were associated with no ice, according to the study. Between 1997 and 2005, 90 percent of bear sightings were associated with no ice. The number of bears sighted also increased during the study’s duration from 138 bears in the period of 1979 to 1987, 271 bears between 1988 and 1996, and finally to 468 bears between 1997 and 2005. NSF-funded and CPS-supported scientists like University of Wyoming’s Hank Harlow among others, are conducting polar bear research in part to better understand climate change’s impact on the creatures. Scientists studying sea ice extent have identified a decline in fall freeze since the late 1970s, a trend they suggest is related to climate change.

Spies Like Us

A satellite image of the East Siberian Sea from 1999-2008. This image has been degraded to hide the satellite’s true capabilities. Photo: New York Times.

The New York Times reports that the Central Intelligence Agency (CIA) is sharing data with climate science after resuming a collaboration that had been cancelled by the Bush administration. The two disparate groups seek to “assess the hidden complexities of environmental change … and insights from natural phenomena like clouds and glaciers, deserts and tropical forests,” according to the article. Last year the collaborators studied reconnaissance satellite images of Arctic sea ice to identify summer melts from climate trends. In addition, the CIA has declassified images of the ice pack to speed the scientific analysis.

Filmmaker To Stop at Seattle Boat Show

The 57-foot Nordhavn Bagan will be on display at the Seattle Boat Show. Filmmaker Sprague Theobald piloted this vessel through the Northwest Passage last year during the making of a documentary. Photo: Northwest Passage Film

If, like us, you have been waiting to get a glimpse of more detailed footage from Emmy Award winning filmmaker Sprague Theobald’s 2009, five-month journey through the Northwest Passage, look no further than the 2010 Seattle Boat Show January 29-February 6, 2010. Theobald will show unreleased footage and give tours of his 57′ Nordhavn Bagan, which transported him and a small crew stocked with family members from Rhode Island to Washington State, via the Arctic.

In Out of The Cold

While much of the northern hemisphere is experiencing unusually bitter cold temperatures, climes in the far north are much warmer than usual. According to a report from the National Snow and Ice Data Center (NSIDC), the December average air temperatures over the Arctic Ocean region, eastern Siberia and northwestern North America ranged between 2 to 7 degrees Celsius. According to the report, Arctic Oscillation (AO) is likely causing the temperature disparities. Scientists refer to the current trend as a “negative phase” of AO, defined by high pressure systems in the Arctic and lower-than-normal pressures in middle latitudes.

The image below shows air temperature anomalies for December 2009, at the 925 millibar level (roughly 1,000 meters [3,000 feet] above the surface) for the region north of 30 degrees N.  Warmer-than-usual temperatures over the Arctic Ocean and cooler-than-normal temperatures over central Eurasia, the United States and southwestern Canada are documented here. Areas in orange and red correspond to strong positive (warm) anomalies. Areas in blue and purple correspond to negative (cool) anomalies.

Source: National Snow and Ice Data Center, courtesy NOAA/ESRL Physical Sciences Division

Arctic Studies Pioneer Dies

Arctic studies pioneer and philanthropist Evelyn Steffannson Nef died on Dec. 9, 2009, at 96. Founder of Dartmouth College's arctic studies program, Nef also published two books on the Arctic. Photo: Courtesy news.uchicago.edu

Evelyn Stefansson Nef died Dec. 9, 2009 in her Washington D.C. home at the age of 96. Nef was an author and philanthropist, and along with her husband, she helped found the first arctic studies program at Dartmouth College. Nef’s first two books, published in 1943 and 1946 respectively, were about Alaska and the Arctic. The University of Alaska granted Nef an honorary doctorate in 1998 for her foundational role in the early days of the field of arctic studies. Read more about Nef’s life here.

—Rachel Walker


In the Media

October 27, 2009
Anchorage350

A group in Anchorage, Alaska, participates in the Climate Action day last weekend. Carl Johnson Photography, courtesy http://www.350.org

Last Saturday (October 24) was the International Day of Climate Action. Over 180 countries participated in more than 5000 activities around the globe to raise awareness of advances in climate science and to stimulate action regarding climate change. Organizers hope grassroots movements like this will encourage world leaders to develop a new climate treaty when they meet in Copenhagen this December. The day was organized by 350.org.

350

Greenland's Disko Bay, recipient of the speeded-up outflow of some of Greenland's fastest-moving glaciers. Click on the picture to find out what '350' refers to.

The Interior Department’s proposal last week to designate some 200,000 square miles of northern coastal Alaska and US territorial waters for polar bears met with criticism from both sides. Alaskan agencies indicated they would challenge the proposal, seeing it as an obstacle to the state’s oil and gas interests; conservation agencies, on the other hand, said it did not go far enough to protect polar bear habitat, which is shrinking due to melting sea ice.

Meanwhile, Andy Revkin reports in The New York Times that the Fish and Wildlife Service concluded that Pacific walruses, suffering as a result of habitat loss, should be considered for protection under the Endangered Species Act. Walruses use sea ice as a “floating nursery,” Revkin says, while they hunt for clams on the coastal seafloor; shrinking ice has meant that increasing numbers of walrus come ashore. Recently, walrus stampedes have killed scores of these animals.

On his Dot Earth blog, Andy Revkin includes a dispatch from David Rothenberg, who is sailing on a Dutch schooner with other artists on The Arctic Circle cruise. They wish to explore the “nexus where art intersects science, architecture, and activism,” according to The Arctic Circle project’s Web site. Rothenberg’s description of a few of his colleague’s projects suggest they DO experience the Arctic differently than do average tourists, as Rothenberg asserts (toast, anyone?). The writing calls up bold images, such as this description of bears feasting on a whale carcass: ”Their bloody faces smile as they chew on rancid whale meat.”


Tapestry waving in the wind

October 19, 2009

While trying to catch up on everything we missed last week, we just noticed that John Whiteman posted another in his series, “Polar Bears of Summer,” for Exploratorium’s NSF-funded outreach project, Ice Stories.  As ever, Whiteman delivers the goods from the USCGC Polar Sea, where the Hank Harlow-led team of University of Wyoming researchers are tracking and re-examining a set of bears they collared last spring.

US Coast Guard Cutter Polar Sea navigates pancake ice in the Arctic Ocean.

US Coast Guard Cutter Polar Sea navigates pancake ice in the Arctic Ocean.

The ship ran into some heavy seas, leading to all personnel being restricted from going on deck. Whiteman writes that the sea ice responding to the swells was “like watching an enormous tapestry waving in the wind.” If you haven’t checked out Whiteman’s dispatches, you’re missing the boat (and the bears).

Coasties and Helos and Bears, Oh My!

October 5, 2009
Coasties prepare a helicopter for flight operations supporting the Harlow polar bear study. Courtesy PA office, USCGC Polar Sea.

Coasties prepare for flight operations supporting a group of polar bear researchers, including a team led by Hank Harlow (U Wyoming). Courtesy USCGC Polar Sea.

The USCGC Polar Sea is out on the Beaufort Sea region of the Arctic Ocean looking for polar bears right now–and you can go too, via three different blog-style reports:

John Whiteman has an ongoing series of posts for the San Francisco Exploratorium’s on-line exhibit, Ice Stories, an NSF-funded project. The museum’s staff train and equip scientists for actual in-the-field reporting.  Whiteman, a PhD candidate at U Wyoming, obviously is equipped to offer technical details, and he uses plain language (and great pictures) to explain the science.  Last week he reported that lack of sea ice was hampering the study, as thin ice conditions were preventing the helicopter from setting down near bears the research team had located via the radio collars with which they had outfitted the bears during spring efforts. They have since been able to land and have collected some data from the study bears.

We know this from Christina Galvan’s PolarTREC blog. Galvan is a teacher sailing with the polar bear team courtesy of ARCUS’ PolarTREC program (also funded by NSF). In addition to reflecting on the science projects underway, Galvan faithfully answers her students’ excellent questions and tells about life on the ship.

The USCGC Polar Sea’s Public Affairs Officer’s report. This is a weekly news posting aimed at family and friends of the Coast Guard. This is the place where we read about ship operations, for example a snarl in the steering gear that required “steering by vice-grip” for a day or so  The PA also updates a photo page routinely.

The ship leaves a wake of broken ice. Photo courtesy USCGC Polar Sea.

The ship leaves a wake of broken ice. Photo courtesy USCGC Polar Sea.

In addition to these sources, National Geographic and Polar Bears International also have media teams on the cruise.  We’ll keep an eye out for their material as well.