Bumblebee

Bumble bee clings to fireweed flower 





The final time I saw bumblebees this year they were barely moving, none of them in flight.

Some crawled slowly around the tops or sides of wildflowers on that cool, late-August afternoon. Others remained still, their fuzzy black-and-yellow forms clinging to the flowers and barely budging even if nudged by a fingertip. A leg was extended and waved in slow motion, as if to protest the intrusion.

It seemed likely the end was near for these and other bumblebees that reside in the Anchorage Bowl and Chugach Front Range. But what, exactly, did that mean? I recognized again how little I know about these likeable neighbors. I promised myself I would learn more about them, and that I’ve done.

Bumblebees have long been one of my favorite Alaska insects. I welcome their buzzing reappearance each spring, one of the sure and early signs that our northern landscape and many of its inhabitants have begun their emergence from winter’s dormancy. This always seems something of a miracle after many months of subfreezing cold and snow and ice. I then enjoy the summer-long presence of these big and boldly colored insects as they loudly whirr from flower to flower, feeding and pollinating their way through subalpine and tundra meadows.

One of the things that initially attracted me to bumblebees—and bees generally—is that they’re not aggressive toward humans in the way that yellowjackets and other wasps can be. I’ve found online descriptions of them ranging from “peaceful” to “docile” and though I don’t perceive bumblebees to be passive creatures, they certainly seem accepting of us humans while they go about their daily routines. Or maybe they simply don’t pay much attention to us.

Still, bumblebees can and will sting when sufficiently provoked or threatened. One way to do this is to disturb a bumblebee nest. Which leads to one of the facts that I’ve recently learned about bumblebees: like honeybees, they are “social” insects that reside in hives. For some reason, I had long assumed that bumblebees were solitary creatures, perhaps because I have never stumbled into (or otherwise encountered) a hive, whereas I’ve found plenty of wasp nests in the wild.

It turns out there are several types of native Alaska bees that do lead solitary lives, but not bumblebees. My research informed me that they build nests in the ground, often in the abandoned burrows of small mammals or under downed trees or other debris.

Why I have never encountered a bumblebee nest during my rambles through their homelands remains something of a mystery to me, though perhaps it’s a good thing I haven’t done so.

More on bumblebee stings: only females have a stinger. And unlike honeybees, the stingers do not have barbs; thus bumblebees can sting multiple times. The venom introduced during a sting normally leads to only local swelling, but people allergic to bee stings can have more severe reactions.

But enough about stings. Bumblebees are among the most important pollinating insects to inhabit the north and are considered generalists because they pollinate a wide variety of plants. Many have evolved what’s called a “pollen basket” on their hind legs to haul the powdery fertilizing material around.

Researchers have so far found nearly two dozen species of bumblebees in Alaska (and about 100 species of native, wild bees in all). They range from the Panhandle to the Arctic and comprise close to half of the 50 or so species so far identified in North America. Among them are four species found nowhere else in the United States.

Though researchers say most of Alaska’s bumblebees appear to be doing well, and even thriving, the Alaska Center for Conservation Science reports that one species, Bombus occidentalist, has declined across its range and a petition has been submitted for its listing under the Endangered Species Act.

Perhaps the reason that bumblebees have fared well in Alaska is that they’re well-adapted to harsh conditions. One Alaskan entomologist, Derek Sikes, has commented that “They’re pushing the envelope of what is possible for an insect” in northern climates.

Which leads to the question: why do bumblebees do so well in the far north?

For one thing, they’ve evolved large (at least by insect standards) and rounded bodies that are covered in thick, insulating hair. For another, they can rapidly vibrate their flight muscles not only to fly but also to generate warmth. As reported by “Atlas Obscura” editor and writer Gemma Tarlach, bumblebee queens can transfer the warmth generated by those flight muscles into the abdomen, to warm their eggs.

To again quote Sikes, bumblebees “thermoregulate quite amazingly.” He further notes that bumblebees are in fact warm-blooded creatures: “They generate heat, it’s just not constant the way mammals do. But it is internal, not just from basking in the sun.”

And how amazing is that?

It turns out that the social organization of bumblebees is also more remarkable than a person (at least this nature writer) would imagine.

To begin, only queen bees born that summer enter winter hibernation, spending the long frigid season in an underground burrow of some kind. All other members of a hive die (including the “old” queen that gave birth to the new one).

When she emerges from her subterranean shelter in the spring, the queen will find a new nest site and lay some of her eggs. Those initial eggs will produce female worker bees, while ones that hatch later will yield potential new queens and males to mate with them.

How all this works is beyond me and the scope of this particular column. For those who wish a more comprehensive discussion, I’d recommend two online sources for starters. First, there’s Gemma Tarlach’s article, “What’s Up with Alaska’s Wild, Wondrous, ‘Warm-Blooded’ Bumblebees?” later reposted online by High Country News as “Alaska’s bumblebees are thriving.” And also Anne Sutton’s “The Brief, Busy Life of the Arctic Bumblebee,” an Alaska Fish & Wildlife News publication.

I imagine I’ll return to bumblebees in a future City Wilds column. But for now I’ll end with this. Some readers may recall that I wrote a column about this summer’s unusually prolific flowering of monkshood in local meadows. Well, on reading Anne Sutton’s piece about bumblebees, I learned that they are “partial to monkshood.” The wildflower “can’t thrive without the bumblebees, its flower having evolved into the animal’s very size and shape.”

I like that, a lot. And it suggests to me that this past summer was a very good one for local bumblebees, for monkshood to be so extraordinarily abundant. It also pleases me that two life forms I’ve long admired have such an intimate relationship. That alone was worth the effort of learning more about the bumblebee.

Anchorage nature writer and wildlands/wildlife advocate Bill Sherwonit is a widely published essayist and the author of more than a dozen books, including “Living with Wildness: An Alaskan Odyssey” and “Animal Stories: Encounters with Alaska’s Wildlife.” Readers wishing to send comments or questions directly to Bill may do so at akgriz@hotmail.com

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