Researchers hope 'Bombus polaris' can shed light on climate change

DALTON HIGHWAY, Alaska — 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 looked at the prize and says, "It’s the biggest frigging bumblebee I’ve ever seen in my life!"

Woodard, an assistant professor at the University of California-Riverside; her lab manager, Watrous; and a small team of young academics have embarked on a bee-hunting road trip from Fairbanks to Prudhoe Bay and back, almost 1,000 miles all told, more than 800 on the Dalton Highway.

They 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, such as berries, are traditionally prized by Alaska Natives, not enough is known about bee populations and behavior even to spot change when it occurs.

The group now is 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 although the site is actually buzzing with bees, it seems that no matter where you go and when you get there, someone always says, "You should have been here yesterday." Or the day before that.

Two days ago at the Arctic Circle, Jessica Purcell, an assistant professor in the entomology department at Riverside, and her husband, Alan Brelsford, both newbies to the bee business, caught 40 each.

"We had to let some go," said Brelsford, an assistant biology professor at Riverside.

Here, the bees aren’t quite that numerous, and the hunters are every bit as intense as siblings on an Easter egg hunt.

The bee stalkers run and pounce, swiping hand-held nets like the ones butterfly collectors use, calling out, "Bee!" or "Got one!" when they are successful. They pop them into plastic tubes and bring them to Michelle Duennes, a postdoctoral researcher in Woodard’s lab, for identification.

The trip is being financed by a university grant to encourage collaboration among young scientists.

They hadn’t been in the field together before, but given the available grants, "We said, well what’s the craziest thing we could think of doing?" The answer: going north to Alaska to scout the condition of bumblebees in the Arctic, where climate change is occurring at a rapid rate.

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 to the climate already are 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 might arrive to compete with species that adapted to the old conditions.

Some bumblebee populations in more temperate regions already are 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 behavior 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. The polaris hasn’t been studied that much since Bernd Heinrich examined its physiology in the 1990s. For Woodard, 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. Heinrich suggested in his research that a spring queen warms up her ovaries to jump-start the production of eggs to be fertilized 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, the group camps at a gravel pit where pipes and other material for the pipeline are stored. Each captured bee is in a plastic tube, and Duennes 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 might harbor, and places them in a solution that preserves them for genetic study. The bee bodies go into ethanol.

On July 4 at the Toolik Field Station, an Arctic research base run by the University of Alaska-Fairbanks, 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 realize that they found more than 40 Bombus polaris bees along the way.