More concerns about Arctic ship traffic

“A rapid increase in shipping in the formerly ice-choked waterways of the Arctic poses a significant increase in risk to the region’s marine mammals and the local communities that rely on them for food security and cultural identity.”  That’s the conclusion drawn by a group of Alaska native groups and the Wildlife Conservation Society following a workshop last week.

            Before the climate started warming, sea ice had been a major obstacle to large ships traveling in the high Arctic, but that is less and less of an issue for the ships, and more and more of an issue for marine life.

“The disappearance of summer sea ice from the region’s coastal areas is leading to major changes in this part of the world,” said Martin Robards, director of the Wildlife Conservation Society’s Beringia Program. “The presence of large ocean-going vessels is expected to increase as the region becomes more attractive to both international shipping and extractive industries seeking minerals, oil, and gas. The northern sea route is 30 percent shorter than the comparable route linking northern Europe to Asia via the Suez Canal, which only supports the conclusion that the Bering Strait is likely to get busier.”

While this workshop and its conclusions focus on the marine mammals in the Bering Sea and the waters around Alaska – a region that is far from the range of the narwhal – it is just as true for the eastern Canadian Arctic and the waters around Greenland where narwhals will be similarly affected.

One strategy suggested by the workshops participants for combatting the effects of increased shipping was to enforce a reduced speed for shipping through the Arctic region. The strategy has been successful in reducing ship collisions with the imperiled North Atlantic right whale along the U.S. East Coast, and it is worth trying in the North as well.  

But ship strikes are primarily an issue for larger whales like bowheads.  Narwhals are more likely to be affected by the low-frequency noises that the ships emit. The sea unicorn is skittish and the noise from increased shipping is certain to be a significant disturbance to their feeding, migration and communication.

“There is mounting evidence that human-generated sounds in the marine environment have negative effects on marine life,” said Howard Rosenbaum, director of The Wildlife Conservation Society’s Ocean Giants Program. “An increase in background noise from increased shipping, coupled with increases in underwater noise from industrial activities and other potential stressors, is of great concern for the Arctic’s marine species and their important habitats.”

An even greater threat comes from increased oil exploration and the likelihood of an oil spill in a region with little or no capacity to contain it.  As I wrote here last year, the U.S. Geological Survey believes that there may be as many as 50 billion barrels of oil off the coast of Greenland, a quantity similar to that of Libya, which could provide an economic boost that would transform the island and sever its financial dependence on Denmark.  The expense of drilling in the region, along with the short drilling season and the risks that oil rigs would get rammed by icebergs, had made oil drilling in the region unattractive.  But increasing oil prices, satellite tracking of icebergs, and warming temperatures have created a huge opportunity and growing interest among oil companies around the world.

“The lack of international response capability to a spill in these waters is a serious concern in light of the increased interest in oil and gas exploration, or the rise in transportation of petroleum products by tankers through the Arctic,” added Robards. “A comprehensive approach is clearly needed to prepare for a potential environmental disaster in a region where marine mammals transit both national and international waters.”

Hopefully the concerns raised at the Alaska workshop will be heard by U.S. policymakers and the Coast Guard and shared with their counterparts in Canada and Greenland.  Arctic marine life will have plenty to deal with from the warming climate without having to also defend themselves from a flotilla of noisy ships.

Retreating ice means orcas are increasing threat to narwhals

            The effect of the declining extent of sea ice in the Arctic continues to raise new questions among scientists and generate attention in the media.  The latest stories reveal concerns about killer whales and what impact they will have on prey species like narwhals as disappearing ice provides the orcas with greater access to the region.

            On my first visit to Arctic Canada in 2008, I watched as a pod of about 12 killer whales chased a group of perhaps 200 narwhals through Eclipse Sound in northern Baffin Island.  That’s when I first began to wonder how much of a threat the orcas are to the ice whale.  My guide that week, who has lived his whole life in the region, had never seen a killer whale, so I suspected that they must not be common in the area.  But like most questions about wildlife in the Arctic, answers aren’t easy to come by.

While killer whales are considered resident in the Canadian Archipelago when the water is ice free, their numbers are small and they are seldom observed because they are spread out over a wide area. Despite their small numbers, however, killer whales may be the top predator on narwhals – next to humans – according to many Arctic marine mammalogists, including one who referred to narwhals as “orca candy.”   

“My general feeling,” said University of Washington biologist Kristin Laidre, “is that the densities of killer whales in the Arctic are low.  Sightings of killer whales are, in general, pretty rare. We do know that they feed on narwhals and belugas, and some killer whale pods, it seems, have evolved to know precisely where narwhals are located in summer, especially in the southern part of their range like in Foxe Basin or Hudson Bay.  There they show up pretty regularly, as narwhals are a predictable prey resource that occur in high densities in ice-free shallow waters.” Killer whales are sighted only rarely along the coast of West Greenland, she added.

Laidre is one of very few biologists to have observed orcas feasting on narwhals.  In August 2005, while satellite tagging narwhals in Admiralty Inlet in northwestern Baffin Island, she and two colleagues watched as a pod of 12 to 15 killer whales attacked and killed at least four narwhals among a group of several hundred over a six-hour period.  From their observation point at Kakiak Point, they saw what they described as “vigorous surface and diving activity” by the orcas which resulted in a large oiled area on the water, presumably from whale oils released from the dead narwhals, and congregations of seabirds. It appeared that the orcas consumed the narwhals below the surface.  The biologists had tagged several narwhals a few days before the attack, so they were able to monitor the movements of the animals in response to the killer whale aggression.  According to Laidre, the narwhals in the area suddenly moved into shallow water as the killer whales approached, some forming tight groups and others lying still at the surface or moving slowly and quietly.  One narwhal even stranded itself on a beach and thrashed its tail violently for 30 seconds as if to warn its pod mates.  During the attack, most of the narwhals in the area moved as much as 50 miles south and spread out much more than usual.  The animals resumed their normal behaviors within an hour after the killer whales departed the area.
            In a surprising coincidence, given how seldom killer whale attacks on narwhals are observed, another biologist watched killer whales prey on narwhals on the exact same day in Repulse Bay, about 400 miles south of where Laidre made her observation.  Laidre surmised that if the predation level from these two attacks were representative of the daily activity of killer whales in the region, then 200 to 300 narwhals are likely killed on their summering grounds by orcas during the two months of open water in the area.  Coupled with the annual harvest by Inuit hunters and predicted reductions in sea ice, enabling killer whales to hunt narwhals over a longer period each year, this mortality rate raises questions about how these elements will affect the sustainability of narwhal populations.

Ice entrapments an increasing concern for Arctic whales

            The recent news about the beluga whales caught in an ice entrapment north of Russia reminded me of the last such event that made the news, one that entrapped 600 narwhals just off Baffin Island in northern Canada.  Given the changing ice conditions caused by global warming, our Arctic whales are likely to experience increasing numbers of ice entrapments in coming years.

Entrapped belugas await icebreaker in Russian Arctic

On that November day back in 2008, the ice near the village of Pond Inlet apparently closed suddenly, leaving the whales just a few small holes from which to breathe.  Those holes were closing, too, while the next nearest place to surface and breathe was believed to be about 30 miles away.  The animals were certain to die, so the Pond Inlet Hunters and Trappers Organization advised its members, with approval by federal officials from the Department of Fisheries and Oceans, to kill the narwhals rather than let them suffer and die.  As heartbreaking as the situation was, it was probably the right decision – the entrapment was a natural event, the whales were certain to die after what would surely have been a long and stressful experience, and their harvest by the hunters not only reduced the animals’ suffering but provided an unexpected bounty to the local Inuit communities.

Entrapments such as this are extremely rare.  David Angnetsiak, a 50-ish hunter in Pond Inlet, told me it was the only time in his life that he had seen narwhals inescapably trapped. He said that most of the entrapped narwhals were females and young, reflecting the Inuit belief that bull narwhals can hold their breath longer and were probably better able to reach open ocean. The last such entrapment that local hunters remember occurred in 1943.

While news reports indicated that federal officials said the harvest was the most humane way to deal with the entrapment, there was considerable public outcry that the government didn’t send in an icebreaker to open a passage for the trapped whales.  The Humane Society International/Canada called the government decision “unconscionable” and noted that the narwhal harvest was “inherently inhumane.”  Others from the South agreed, though Mike Richards, a special administrative officer for Pond Inlet, told the Globe and Mail of Toronto that “It’s just a misfortune of nature.”

Ice entrapments, called savssats by the Inuit, are an increasing concern and they probably happen much more often than records suggest, since the Arctic is so thinly populated and no one is around to observe or document entrapments in the vast majority of the region.  Nonetheless, narwhal biologist Kristin Laidre told me that four ice entrapments that resulted in the deaths of more than 700 narwhals occurred in 2008 and 2009 – the first one ever documented in East Greenland, as well as two in northwest Greenland and the very large one near Pond inlet.

Laidre is beginning to examine the distribution and timing of known ice entrapments and look at the trends in the breakup of sea ice on the narwhal’s summering grounds. She has found what she calls “strongly significant trends” that suggest that the ice is forming later and later.  “Over a 30 year period there is a three to four week difference in when the ice forms,” she said.  “If ice formation is a clue to the narwhals that it’s time to get out of their summering grounds, then the trigger is changing, the pattern is changing.”  Is that change in the formation of ice making narwhals more vulnerable to ice entrapments?  Laidre hypothesizes that it may be the case, though there is precious little data from which to draw conclusions just yet.  But the hints she has found so far are another indication of the dangerous implications of global warming.

Tracking migrating narwhals

Many news outlets have reported this month about a study in northern Canada aimed at tracking narwhal migrations by attaching satellite tracking devices to the whales and monitoring their movements.  It’s a great project that will hopefully shed new light on population dynamics, migratory corridors, and how declining sea ice is affecting the species.

Some news reports suggested that this project is new, but that’s not true.  The effort has been underway for about a decade, and I spent two weeks with the researchers in the summer of 2010 in the same location they worked this year in a challenging effort to capture narwhals for study.

Narwhal research camp in Tremblay Sound

Based in Tremblay Sound, a fjord in northern Baffin Island in the province of Nunavut, the 13-man research team started out by spending more than a day just setting up camp – which included 1,800 pounds of food, three gas grills, two zodiacs and outboard motors and drums of fuel, giants nets, high-tech scientific equipment, and a 25-foot tall radio antenna.  As we finished preparing camp, we all glanced up in unison as our first massive movement of narwhals swam by. 

Like a child’s bath, at first we just heard gentle splashing noises in the distance from the narwhals’ repeated surfacing for air and an occasional whooshing sound as they exhaled.  Then the whales came into view, swimming in groups of threes and fours and sixes, most appearing quite dark like they were not yet very old, some with pinkish gray calves that looked like tiny swimming sausages, and all porpoising at the same speed in the same direction with little concern for the crowd of onlookers standing on the shore less than 50 yards away.  As we watched, our mouths hung open and I could barely catch my breath, so pleased were we with their seeming tameness and abundance.  There must have been 200 of them, and they took more than 10 minutes to pass our camp.  If the scientists had worried about whether narwhals were going to be in the area, those worries quickly disappeared.  Little did we know then that what we believed were the same animals would swim by us repeatedly two or three times a day for the next several weeks.  Watch my video of the narwhals parading by.

Researchers capture a narwhal for tagging.

Unfortunately, we didn’t catch any narwhals while I was in camp.  Day after day, the whales approached the nets numerous times, and every time they must have detected the nets and swam under or around them.  After I left, however, the researchers acquired a different net that apparently was more difficult for the whales to detect, and just 30 minutes after the new net was deployed, they captured their first narwhal.  In the next four days they caught five more.

“You can count whales from the air, you can count them from land, you can see what the herd is doing, but you don’t really get an idea of what an individual does on a daily basis [without tagging them],” said Jack Orr, the chief scientist in charge of the project and a biologist with the Canada Department of Fisheries and Oceans.  “These tags provide us information on where they are geographically on the Earth, but we also get an idea of how they use the water column.  Tags will tell us how long a whale is at a certain depth, and then we can set up dive profiles…Coupling this with information on water depths and what animals use these depths – we know, for instance, that turbot (Greenland halibut) and crustaceans live on the bottom, we know that squid are pelagic so they’re in the water column – and working with other data on ice and other environmental parameters, we can determine what these animals are doing over the course of a year.  It gives us insights into not only its movements but also its behavior.”

By late November, all of the narwhals the team tagged the previous August were in the middle of Baffin Bay at the edge of the pack ice, exactly where it is known that most narwhals spend the winter.  But the scientists were intrigued to see that some of the tagged whales traveled together the entire route while others took widely varying routes to the same destination, including one who went all the way to West Greenland before returning to Baffin Bay.

It will be exciting to see what route this year’s tagged narwhals take to their wintering location, and if they return to Tremblay Sound next summer.

Shipping, oil exploration add to narwhal threats

News from the Journal of Commerce this week indicates that about 350 cargo containers slip from transport ships into the ocean every year, and that number nearly doubles to 675 if a ship loses multiple containers at once.  It’s a much smaller number than the 10,000 containers per year that had been circulated for years, but still a worrisome figure.  It’s just one source of the abundance of trash in the world’s oceans and a continuing source of concern for the health of marine life, especially whales.

Until recently, Arctic marine life hasn’t had to worry much about massive ships traveling through its habitat and affecting its behavior.  But the retreating sea ice and the expected opening of the Northwest Passage is soon going to change that, as will the increasing efforts to explore and drill for oil and other minerals that previously had been inaccessible due to the ice.

According to The Wall Street Journal, the U.S. Geological Survey believes that there may be as many as 50 billion barrels of oil off the coast of Greenland, a quantity similar to that of Libya, which could provide an economic boost that would transform the island and sever its financial dependence on Denmark.  The expense of drilling in the region, along with the short drilling season and the risks that oil rigs would get rammed by icebergs, had made oil drilling in the region unattractive.  But increasing oil prices, satellite tracking of icebergs, and warming temperatures have created a huge opportunity and growing interest among oil companies around the world.

The political wrangling over what country controls the rights to oil and gas and other minerals at the North Pole, including the bizarre effort by two Russian submersibles to stake aclaim to the area by placing that country’s flag on the seafloor at the pole, is a testament to the great potential wealth to be found there.  In 2010, a British company drilled the first exploratory oil wells off Greenland in more than a decade, and the same year the government awarded more than a dozen new exploration licenses to companies from several nations.

These developments are alarming to a number of groups, including those concerned about the health of narwhal populations.  Narwhals are skittish and the noise and increased shipping resulting from increased industrial activity is certain to be a significant disturbance to their feeding, migration and communication, to say nothing of the threat of oil spills, which could be devastating. 

Representatives of the fishing industry in Greenland have also publicly expressed their concerns about the effect that oil exploration will have on commercial fishing, though some narwhal biologists worry about the fishermen, too.  It is predicted that the loss of sea ice will open up additional areas for expanded fishing for halibut, the primary prey of narwhals and a species with snow-white meat that is high in fat and reportedly rich in flavor, making it popular for sushi, sashimi and smoking.  It’s a worrisome possibility, especially considering that when commercial interests compete against wildlife for a resource, the animals almost always lose.

Narwhals have a very restricted diet, with Greenland halibut being their predominant prey.  Halibut are widely distributed in the North Atlantic, and commercial fishermen traditionally harvested about 20,000 tons per year in the fjords of northwest Greenland using long-lines and gillnets.  An additional offshore fishery developed in the 1990s in Davis Strait that now captures more than 10,000 tons of halibut each year, and efforts are underway to open up additional fishing grounds in the deep waters of central Baffin Bay, where most narwhals do the majority of their feeding. The more the ice recedes, the more fishing is likely to take place, leaving fewer and fewer resources for the narwhals and adding to the increasing headaches the whales will face from the industrialization of Arctic waters.

Narwhals contributing to mounting climate change data

While the major heat wave last week may only hint at the long term climate changes taking place on Earth, the indisputable evidence from around the world – especially in the Arctic – continues to mount.  Even narwhals have been used to collect climate data.

Photo by Paul Nicklen

University of Washington biologist Kristin Laidre has found a new and unusual use for what may be the narwhal’s greatest behavioral claim to fame – their incredible ability to dive to great depths.  In 2006 and 2007, Laidre successfully attached satellite transmitters to14 narwhals in Melville Bay on the west coast of Greenland, and in addition to collecting data on the animals’ geographic positioning, the tags also recorded the temperature of the water as they dived to the bottom.  While Laidre knew that temperature data would be somewhat insightful to her narwhal research, she also guessed that oceanographers and climatologists might find the data useful as well.  It is difficult to use traditional oceanographic measuring devices to monitor water temperatures at great depths, especially in the winter when the water is frozen over for many months.  As a result, researchers have little data from the middle of Baffin Bay to feed into their climate models.  Instead, they have used temperature readings from coastal locations or estimates calculated from historic data, which clearly provide only a hint of the true picture.

“The gliders that oceanographers occasionally use to collect this data sort of look like a streamlined narwhal, with a long pointy antenna, but they’re not as smart as narwhals because sometimes they can’t find the surface and get caught under the ice,” Laidre said. When the narwhal-collected temperature data was published in a scientific journal in 2010, it generated considerable media attention, not only for what oceanographers learned about water temperatures but also for the unusual way the data were collected.  Thanks to the narwhals, water temperatures were determined to be about 1.8 degrees F warmer than what the climate models predicted, and the surface isothermal layer – a layer of water that is at a constant temperature – was 160-260 feet thinner than previously believed.

“I’m not an oceanographer, but for me the excitement was the proof of concept -- that it worked and we collected useful data and the scientific community seemed to be interested in it,” Laidre added. “[The data] suggested that Baffin Bay has continued its warming trend, though I don’t know that it was terribly surprising to the oceanographers.”

Similar data is being collected by narwhals along the East Greenland coast this year.

The marine world's champion deep divers

            The extreme hot weather that has taken over most of the U.S. in the last week or more has most of us wishing for an opportunity to dive into the ocean.  And yet here at the beaches of New England, the water is too cold for most people to spend much time in without a wetsuit.  That’s not a problem for narwhals, of course, as they are among the champion deep divers of the marine world and are well suited to doing so in the coldest of waters.
          With a layer of blubber three or four inches thick, narwhals have no difficulties surviving in the extreme cold.  At great depths, where it is often even colder but where they must dive to feed, they are faced with pressures greater than 2,200 pounds per square inch, which they withstand with a flexible and compressible rib cage that can be squeezed without harming them as pressure increases. To carry along enough oxygen to sustain them on deep dives of up to 25 minutes, they have evolved several nifty solutions, including an enormous concentration of oxygen-binding myoglobin in their muscles, more than twice that of most seals and eight times as much as land animals, enabling them to swim under water at speeds of one meter per second for 20 minutes without taking another breath.  With muscles better suited for endurance than for speed, narwhals can save even more oxygen by turning off the blood flow to non-critical organs and other body parts.

When they are diving to feed on the bottom, they often do so repeatedly to depths in excess of 1,500 meters.  The transit from the surface to the bottom is typically a 30 minute round trip, mostly spent swimming straight down and straight back up.  During most of the year, they make that round trip 10-20 times a day every day all day long. 

But Jack Orr, a biologist with the Canada Department of Fisheries and Oceans, told me that narwhals may also use several other diving strategies.  When they are living in dense ice, they may often use a V dive for feeding and a U dive for finding their next breathing hole.  During a V dive, the animals dive straight down to feed at a certain location where they know they can find food, and then they swim straight back up to the surface to a different known breathing hole.

          “Whereas with a U dive,” Orr said, “they’re going down and then going horizontal for a while and then they’ll start their dive up toward the surface again.  What we presume is that they’re getting to a certain depth and then using their echolocation to find their next breathing hole. If you’re 400 meters below the surface and you start looking for a hole and you find one 400 meters away versus 50 meters away, then you can decide whether you have enough breath to go forward to the next hole or, no, I don’t have the air so I have to go back to my original hole.  These animals are living in such dense ice over the winter months that they’re coming up in breathing holes that aren’t really even a hole that you would see at the surface.  That’s a behavior that they’ve adapted to navigate in dense pack ice.”

Whatever they do down there and however they capture their prey, their extreme diving behavior certainly makes them unique among the world’s cetaceans, and gives me another reason to be in awe of their remarkable lifestyle.