Photo credit: Zoe Tyson
An obsession with bees offers unexpected pleasures. I stand, motionless but ready, by a clump of flowers. Then, the quick swoosh of the net, the moment of uncertainty while the results are still unknown, and finally, the belly leap of joy at a successful catch. Bee hunting has been a surprising side benefit of my quest to learn about native bees.
Five years ago I never would have thought that I would find bee hunting a delight or that I would fall in love with a battery of insects, and yet I have, all thanks to the discovery of one small fact: honey bees can’t pollinate tomatoes. That piece of information shook my world. I’ve gardened my entire adult life, had a garden design and coaching business, taught gardening classes, and yet, somehow I had never learned that when it comes to tomato pollination, native bumble bees are the masters and Euro-import honey bees don’t even have the know-how to be apprentices. How had I missed that fact? Was I just dim?
So I started asking around and discovered that most people knew almost nothing about bees. Few knew that honey bees aren’t North American natives, and no one knew that honey bees can’t pollinate tomatoes or that North America has 4,000 species of native bees, some of which are fine tomato pollinators.
I set out to learn more about these native bees and became just a little bit obsessed. I thought that everyone should know about our bees, and so with the zeal of the recently converted, I plotted. Articles would be written, classes taught, it would be great. Only, no matter how I tried to stuff bee ID facts into my head, they just slipped out. I decided that I needed a class and found one down in the Carmel Valley of California, where I heard a story that transformed my view about bees.
The story was about Franklin’s bumble bee (Bombus franklini
) and was told by Dr. Robbin Thorp, the world expert on Franklin’s bumble bee. Robbin hasn’t seen a Franklin’s bumble bee since 2006; neither has anyone else. The bee is probably extinct, and Robbin’s hypothesis on why is a tale of greenhouse tomatoes, big business, bigger government, and good intentions gone awry.
The Franklin’s story begins, unexpectedly, with the northern spotted owl. In 1990 the owl was listed as a threatened species under the Endangered Species Act and huge tracts of forest were closed to logging in Oregon and Washington. Uproar resulted, lasting for years. Within the range of the spotted owl lies that of Franklin’s bumble bee — another candidate for the Endangered Species list due to its tiny range. Every Franklin’s bumble bee has historically lived within a 200- by 70-mile oval, elongated to the north and south and centered around Ashland, Oregon, right on the California border. The US Forest Service runs a lot of the land in that part of the world, and in 1998 they contacted Robbin to perform a survey of Franklin’s bumble bee, thinking, according to Robbin, that another endangered species in the area would take some of the heat off the northern spotted owl.
So, for the past 19 summers, Robbin has tramped the hills of southern Oregon and northern California looking for Franklin's bumble bee.
Robbin Thorp hunting for Franklin’s bumble bee on Mount Ashland in Southern Oregon. (c) Paige Embry
The bee Robbin seeks is fat and fuzzy, a teddy bear of a bee. Bumble bees are big, showy bees that often sport colorful stripes and patches, but as bumble bees go, the Franklin’s tends to be on the dowdy side. The bright yellow patch that extends across a Franklin’s back is offset by a somber black abdomen. The US and Canada have 46 species of bumble bees, and any particular area will have multiple species flitting among the flowers. For most of us, to try to determine if a bee is a Franklin’s bumble bee we’d have to catch the bee, put it in a collection jar, pop the jar in a cooler to slow the maddened bee down, and then haul it out and try to identify the relevant markings. Robbin can just glance at a bee, often somewhere off in the distance and tell.
The Franklin’s bumble bee, possibly the first US bumble bee to go extinct, is now only seen pinned in museums. (c) Clay Bolt
When he first started hunting for Franklin’s, Robbin found plenty — 94 that first year, which put them in the middle of the pack for bumble bees in the area, but their numbers plummeted after that. None have been seen in over a decade.
Why? Quite possibly because of tomatoes.
Bumble bees are the preeminent pollinators of tomatoes because they, unlike honey bees, are capable of buzz pollination. Now, pollination is just plant sex — moving the sperm equivalent (pollen) to the female parts (the flower’s stigma). On most flowers the pollen is out in the open, ready for the taking. However, some flowers, including tomatoes, hide their pollen inside
the anthers so it has to be shaken out. A bumble bee does this by grabbing the flower with its mouth and vibrating its wing muscles, which shakes the pollen out just like shaking salt from a shaker. This activity makes a buzzing noise, and so, “buzz” pollination.
Growing tomatoes out-of-season in greenhouses has long been a lucrative business, but because there is no wind or natural pollinators in a greenhouse to shake out the pollen, people would hand-pollinate the tomatoes with a stick, or shake the plants by hand or on a shake table or with a little vibrator — all to get those high-value, out-of-season tomatoes. Then in the 1980s, a Belgian vet started a business that woke bumble bees up when they’d usually be sleeping and put them to work in those greenhouses. No doubt the growers were overjoyed; certainly the business model took off, because by 2004 close to a million colonies of bumble bees pollinated nearly 100,000 acres of greenhouse tomatoes worldwide.
A bumble bee visiting a greenhouse tomato. (c) Clay Bolt
The businesses providing these bees were based out of Europe, and although some of those bumble bees were reared in North America, for a few years, bumble bees were woken in European facilities and the young colonies were shipped back to the US to go to work. With those bees, according to Robbin’s hypothesis, came a European disease (or multiple diseases) that escaped into the wild. It wasn’t only the Franklin’s bumble bee that saw precipitous declines at this time — several other closely-related bees did as well, and all were from the same sub-genus as the European bee being raised for commercial purposes in Europe.
I sat in that classroom in California listening to Robbin and realized that bees aren’t just fascinating alien “others.” They have stories, and their stories are intimately intertwined with ours. So I went hunting for more stories and found them: tales of pestilence and plague, of loss of home and death raining from the skies, and stories of small, everyday actions that might just make a difference. I have fallen in love with bees, and my hope is that by telling their stories I can make others fall in love with them too. I have a grand vision of people out in their yards, bee nets in hand, hooting with pleasure over a successful catch while the voice of a TV announcer wafts out a window saying, “Scientists beginning to suspect linkage between decline in pesticide sales and local stores running out of bee nets.” These are the dreams of a bee lover.
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has a BS in geology from Duke University and an MS in geology from the University of Montana. She has worked as an
environmental consultant, taught horticulture and geology classes, and run a garden design and coaching business. She has written articles for Horticulture
, The American Gardener
, and other magazines. Visit her at paigeembry.com. Our Native Bees
is her first book.