The search for the Arctic bumblebee

One hundred miles north of the Arctic Circle, by the side of a dusty road, two women in anti-mosquito head nets peer at a queen bumblebee buzzing furiously in a plastic tube. “I think it’s the biggest bumblebee I’ve caught in my life!” Kristal Watrous says. S Hollis Woodard looks at the prize and says, “It’s the biggest frigging bumblebee I’ve ever seen in my life!” Hollis, an assistant professor at the University of California, Riverside, USA; her lab manager, Kristal; and a small team of young academics have embarked on a bee-hunting road trip from Fairbanks to Prudhoe Bay and back, covering almost 1,000 miles.

Filling in the gapThey want to find out more about the bees of the Arctic, the planet’s advance experiment in climate change. Melting sea ice and a rising ocean affect its coasts. Longer, warmer summers are changing plant life in the interior, and are bound to affect the lives of insects. But even though bees are by far the most important pollinators for tundra plants, some of which, like berries, are traditionally prized by Alaska Natives, not enough is known about bee populations and behaviour even to spot change when it occurs. That’s what the team hopes to remedy.

I joined the group the night before, and we are now tramping over tundra and through low willows near a maintenance site for the nearby Trans-Alaska Pipeline. The site, called the Chandalar Shelf, lies in the shadow of mountain peaks as sharp as freshly made Stone Age axes — the beginning of the Brooks Range. It is the group’s third day in the field, and my first, and the site is buzzing with bees.

The bee stalkers run and pounce, swiping hand-held nets like the ones butterfly collectors use. They pop them into plastic tubes and bring them to Michelle Duennes, a postdoctoral researcher in Hollis’s lab, for identification. The trip is being financed by a university grant to encourage collaboration among young scientists.

Bumblebees are the only bees that live in the high Arctic. They have adapted to the darkness and cold of wintertime that dips to 60 below zero and then to the explosion of growth and pollination under summer’s midnight sun. And that’s why the bee hunter caravan is on the Dalton Highway. Some changes in the climate are already obvious. Willows are taking advantage of a milder climate to spread north to areas where only the low-lying plants and lichens of the tundra had lived before. Moose follow the march of the willows. Other changes will come. For instance, new species of bees may arrive to compete with species that adapted to the old conditions. 

Some bumblebee populations in more temperate regions are already suffering, partly because of climate change. In September, the United States Fish and Wildlife Service proposed listing the once common rusty patched bumblebee as endangered. And there are gaps in the knowledge of Arctic bees that need to be filled. The group on this expedition wants to help build up information on current populations and behaviour against which to measure change.

One bee dominates the hunts, and the conversation. It is Bombus polaris, the Arctic bumblebee. Other bumblebees live in the Arctic, but polaris survives closer to the North Pole than any other bee except a parasitic species that creates no nests and breeds no workers, laying its eggs in polaris nests. Polaris hasn’t been studied that much since Bernd Heinrich examined its physiology in the 1990s. For Hollis, Bombus polaris is the trophy bee.

It has adapted so well to the cold that by shivering its muscles it can raise its internal temperature to more than 95 degrees when it is 32 outside. It lives around the world, in the northern reaches of Ellesmere Island in the Canadian high Arctic, and in Greenland. It doesn’t just stay warm enough to fly. Bernd suggested in his research that a spring queen warms up her ovaries to jump-start the production of eggs to be fertilised with sperm stored in her body since the previous fall. But by the end of the day at the Chandalar Shelf, no one has yet found a bee they can identify as polaris.

That night, we camp at a gravel pit where pipes and other material for the pipeline are stored. Each captured bee is in a plastic tube, and Michelle first gases them with a can of compressed air from a grocery store. Compressed air, she explains, is not just air. This kind contains difluoroethane, which stuns the bees. She removes the guts to study later for bacteria and viruses they may harbouring, and places them in a solution that preserves them for genetic study. The bee bodies go into ethanol.

The next day, we arrive at an oasis of luxury, the Toolik Field Station, an Arctic research base run by the University of Alaska Fairbanks. The station is a remote scientific outpost. But with the luxury, the bees disappear. For two days, we try sites in and around the station. Here and there someone finds a bee, but they seem to have mostly disappeared. Other scientists at Toolik say that earlier in the year several large snowstorms, with warming spells in between, wiped out nesting attempts by migrating birds, drowning the nests and freezing chicks and eggs. Something similar may have happened to the bees.

But on July 4, I watch as Duennes identifies the first Bombus polaris. Once the trip is over, and the researchers do genetic testing at the University of California, Riverside, they will realise that they found more than 40 Bombus polaris bees along the way, but they don’t yet know that. The first Bombus polaris bee is a gift. 

A researcher who has been using fine mesh nets to capture birds has also caught a number of bees by accident. She gladly turns over two dozens or so. Bumblebees come in many colour combinations of yellow, brown, black and red, and only experts can tell one species from another. In some cases, only a microscopic examination of the male genitalia or DNA analysis can provide a definitive identification. 

But one restored bee has telltale dark colour in a yellow patch on its side. Michelle  and Kristal compared it to illustrations in a guidebook. They won’t say what they think until they bring Hollis in to examine the bee. Even though the long road to Prudhoe Bay is ahead, and a longer road back, when Hollis picks the right bee out of the lineup, Michelle is exultant. “I am almost certain that’s polaris!” After scrupulously considering every possible objection to the identification, everyone in the group raises a glass to Michelle ’s toast: “Extreme bees, extreme people.”