Monday, May 30, 2011

Recalling my amazing narwhal adventures

I almost wish that I had started research on my narwhal book a year later.  Because that would mean that I might have had an opportunity to join a team of Oceans North Canada scientists in the first research expedition to follow narwhals as they migrate from the coast of Greenland to the fjords of Canada’s Nunavut province.  They depart this week and will survey the numbers of narwhals, belugas, bowheads and other whales they see, monitor migrating whale sounds, survey seabirds and trawl for plankton as part of a polar bear food-chain study. Sounds like a great trip.
            But I can’t complain too much.  I’ve had plenty of pretty spectacular narwhal adventures of my own.  The midnight jousting session 50 feet from my campsite on a beach in Koluktoo Bay, the first time I had a clear look at a narwhal tusk, may be the most mesmerizing moment of my life, and thinking back on it now more than two years later still gives me a jolt of excitement that I pray never diminishes.  I’m still not sure whether it was the quiet, slow-motion activities of the whales, the spectacular rocky hillsides and iceberg-filled waters, or the unexpectedness of the experience after having already gone to bed that makes that observation rise to the top in my mind.  But it does. 
          And yet there were plenty of other moments that I won’t soon forget either. The parade of narwhals traveling back and forth day after day in Tremblay Sound, skillfully avoiding the researchers’ nets and providing a daily dose of frustration while impressing us at the same time with their remarkable navigational abilities. The more determined parade of narwhals streaking close by our boat in Eclipse Sound, caring not a whit for the threat we posed, for they were far more concerned about escaping from the pod of hungry killer whales that was chasing them.  The honks and moos and twitters and whistles and creaky doors and other bizarre sounds the whales made as I listened in on their conversations with a hydrophone in the middle of Kolukotoo Bay.  The first time I touched a narwhal – still warm after having been killed just minutes earlier – its skin soft and leathery and firm all at once, and my first taste of its blubber and its meat soon afterwards, something I’ll never say was tasty but which I’m pleased to have shared with the proud hunters.
            I have had weeks of adventures that make me more enamored of the narwhal than when I started writing my book about them.  How it can thrive in its icy world and find food in the dark depths will always amaze me.  And yet despite their great skill and flexibility and physiological adaptations that enable them to undertake their entire life cycle in conditions that few creatures can withstand, and despite what I’ve learned about their somewhat stable populations from the world’s experts, I still worry about them. 
            Today, though, I’m just enjoying those amazing memories.  If you want to keep track of the Oceans North Canada expedition as it follows the narwhal migration, check out

Wednesday, May 25, 2011

No soup for you - Banning shark finning

When I arrived at the Inuit hunting camp to observe a subsistence narwhal hunt not far from Qaanaaq, Greenland, the northernmost municipality on Earth, there were no narwhals to be seen.  But sitting on the beach decomposing were two Greenland sharks.  The hunters told me that the sharks had been scavenging the narwhals that the hunters had harpooned before they were able to haul the whales to shore. So they killed the sharks.
            As disturbing as it was to see, even more disturbing is the practice of “finning” sharks – capturing them, slicing off their dorsal fins, and tossing the rest of the carcass into the water to die – and selling the fins to Asian markets for shark fin soup, a delicacy in China where it is consumed at weddings and other celebrations.  It’s not practiced in the Arctic, but it takes place in all of the other oceans of the world.
Fishermen can sell the fins for more than $40 dollars per pound, with some large fins from basking sharks going for as much as $50,000. (A market in California was selling the fins for up to $699 per pound this year.) Finning, banned in U.S. waters, is responsible for the death of tens of millions of sharks every year, which is causing great declines in shark numbers around the globe. And when the numbers of top predators decline drastically, it has a cascading affect on the entire ecosystem.
            Thankfully, public outcry about finning is beginning to show results.  Hawaii became the first state in the nation to ban the import and sale of shark fins this year, and Washington state soon followed suit.  This week a bill to ban shark fin soup in California, introduced by a Chinese-American legislator, passed the Assembly and is headed to the Senate.  Similar bills have been introduced in other states, including Oregon, where it has passed the House, though final passage is uncertain.
            Whit Sheard of the marine conservation group Oceana said that winning a ban in West Coast states is part of a campaign to build international support for protecting the sharks killed each year for soup. “It’s fantastic that in times like we are in now, something like this can get such enormous bipartisan support,” he told the Associated Press.
            But the battle is far from won. Even if it is banned across the U.S., the practice of finning sharks is still legal in most of the world’s oceans, and high demand for shark fin soup is keeping prices high, which provides an economic incentive for fisherman to continue the practice.  However, high profile Asian chefs, celebrities, and even basketball star Yao Ming have come out in opposition to shark fin soup, so momentum is building.
            Sharks reproduce slowly so it will take a long time to rebuild their populations, but these first steps look promising. And while sharks are responsible for the deaths of many marine mammals every year, including narwhals, they play a vital role in maintaining a healthy marine ecosystem.

Friday, May 20, 2011

The Narwhal Tusk Debate

            Numerous theories have been presented over the centuries to explain the function or purpose of the narwhal tusk, the strangest tooth in nature: as a spear for hunting or a tool for digging, as a weapon of defense or aggression, an instrument for breaking ice or sound propagation, or even as a swimming rudder or an organ for breathing.
Photo by Paul Nicklen

If you search the Internet for an answer, most of the results will be somewhat misleading. The answer you will no doubt find there is that the tusk is a sensory organ that the whale uses to somehow sense something about its environment.  That’s the conclusion of a Connecticut dentist, Martin Nweeia, who has done a great deal of study of the tusk.  But almost all of the narwhal biologists on the planet disagree.  Vehemently.  Yet the media picked up on Nweeia’s announcement of his findings and it raced around the Internet, much to the chagrin of the biologists. The sensory organ conclusion has found its way into natural history museum exhibits, award winning books, and respected publications around the world, yet even Nweeia would agree that he hasn’t amassed the scientific proof of his hypothesis.
The biologists, on the other hand, all stake their reputations on their belief that the narwhal tusk – the male whale’s left tooth, which spirals out to a length of up to eight feet -- is a “secondary sexual characteristic,” like the antlers on a deer, the tail of a peacock, and the mane of a lion.  It’s a physical adornment designed to attract a mate and demonstrate dominance over other males, they say. If it were important for sensing their environment, females would have one, too. (A tiny percentage of females do.) The scientists point to Charles Darwin, who argued in 1871 that “when the males are provided with weapons which the females do not possess, there can hardly be a doubt that they…have been acquired through sexual selection.” Half a century before Darwin, Arctic explorer William Scoresby concluded similarly: “It cannot be essential for procuring their food, or none of them would be without it: nor is it, perhaps, necessary for their defense, else the females and young would be subjected to the power of enemies without the means of resistance, while the male would be in possession of an admirable weapon for its protection.”
I’ve interviewed all of the parties involved, and all are passionate about their position.  Perhaps the harshest critic of the sensory organ theory is biologist James Finley, who wrote to me in an email, “The romance of the narwhal makes people want to fantasize all sorts of bizarre function.  Nweeia is dreaming. It continues to amaze me that practically every account of the narwhal, even some by biologists, has to end with the assertion that we still don’t know the function of the mysterious narwhal tusk. It’s no more mysterious than a moose’s antlers, yet we are loath to let the legend die.”
Nweeia’s conclusion is based on his finding that the tusk has millions of tiny tubules extending from the inner core of the tooth to the outer edge, unlike in any other mammalian tooth, enabling seawater to penetrate to the nerve endings in the tusk. From that finding, he drew his hypothesis about it being a sensory organ, and he has been working to prove it ever since by administering water of varying salinity levels to the tusk of live narwhals and observing their physiological reactions. It has taken five or six years of effort to get results from half a dozen animals, and he is convinced he is right. But he hasn’t published his results, so none of the biologists have been able to review his claim.
So the debate goes on. Though to call it a debate is overstating the situation, because – unlike most scientific debates – those on either side of the question have never communicated with each other.  It’s a stand-off with no end in sight. 

Friday, May 6, 2011

Pollutants in narwhal tissues raise concerns

I’ve paid close attention to the news this week noting that mercury levels are rising in Arctic marine mammals and that diabetes among Arctic natives is on the increase due to the pollutants in the whale meat they eat.  It got me thinking about what that means for narwhals.
Biologist Rune Dietz of Denmark’s National Environmental Research Institute has been investigating the contaminants in the marine environment that find their way into the animals’ vital organs, blubber, and other tissues -- even their tusks -- via the food chain.  While no studies have yet been conducted that have evaluated the health effects of contaminants like heavy metals and industrial chemicals on narwhals, Dietz found elevated levels of cadmium, selenium and mercury, as well as man-made organochlorines like PCBs and DDT, in tissue samples collected from 150 narwhals in Greenland.
These contaminants travel on prevailing winds in the atmosphere and are deposited in the Arctic in the rain and snow.  While concentrations of many contaminants in the environment are slowly decreasing over time, mercury – perhaps the most dangerous one because of the known deleterious effects it has on the brain and reproductive system – is increasing.  About 200 tons of mercury finds its way into the Arctic region each year, about 10 percent of the world’s emissions of mercury.  And the decline of multi-year sea ice due to global warming means that mercury that may have settled on the ice and was having little effect on wildlife is now finding its way into the marine environment where it is accumulating in the tissues of whales and other creatures.
Photo courtesy of Glenn Williams
Dietz is in the midst of several additional studies of mercury contamination in Arctic marine mammals. He has found that polar bears generally have low levels of mercury in their brains because they can rid their system of a substantial amount of mercury through their fur, a process whales cannot partake in since they have no fur. He is also analyzing mercury in the growth rings of narwhal tusks, which, like hair, teeth and feathers, can be a storehouse of pollutants.  “I can go out and get a two meter tusk and get the last 50 year history of that animal’s mercury contamination,” Dietz said. 
Dietz isn’t the only scientist examining narwhal tissue samples to better understand the health of the population. University of Manitoba scientist Gary Stern has collected samples of narwhal livers, kidneys, muscle and blubber to assess contaminants in the whales, and his results somewhat mirror those of Dietz.  He said that climate change may be exacerbating the problem because the accumulation of contaminants in narwhal tissues is dependent on the whales getting access to those contaminants.  As sea ice retreats, he said that more contaminated fish will be available for the whales to feed upon, making those contaminants “bioavailable.”
While Stern agrees with Dietz that little is known about the health impacts of these pollutants, he worries most about what he calls the “synergistic effects” from a wide range of challenges the animals are facing. 
“It’s hard to tell what affects the contaminants are having on their health, but they are one additional stressor they have to deal with,” he said.  “We still have no information that says directly that it’s affecting reproduction or having neurological effects; it’s hard to tell with an animal in the wild.  But these animals are under stress for a number of reasons – changing habitat, noise pollution – and contaminants are just another thing that acts synergistically to possibly making their immune systems not work as well.”