Friday, 26 Sep 2003

TUSCON, Ariz.

This is my final entry of the week, my fifth essay on various entomological and conservation-oriented topics. Sherry Bosse at Grist had contacted me after reading the “Small Matters” article by William Stolzenburg in the Spring 2003 issue of The Nature Conservancy Magazine about the lack of attention given the not-so-charismatic microfauna, the invertebrates. I imagine that Sherry was intrigued, or perhaps amused, by recounted tales of my driving a Toyota pickup truck around the back roads of Tucson, Ariz., conducting “impact collecting” of bees and other pollinators that stuck to my radiator. Well, actually, it was a bit more quantitative and scientific than that. I used Varroa mite-detection sticky boards to catch my hapless prey items. I assume that those were the reasons she invited me to contribute a week’s worth of diary entries to Grist Magazine.

The cactus bee (Diadasia rinconis).

Photo: Elaine Hodges, Smithsonian Institution.

It’s not a big secret that most cars, trucks, and motorcycles are excellent filter feeders as they cruise their way through what amounts to a rich veritable aerial plankton of insect life — just think of those bug splats on your windshields. There is even a wonderful, cheeky insect field guide called That Gunk on Your Car by Mark Hostetler. It has plenty of serious information about the natural history of many common North American insects. I’ve been collecting data on the impact (pun intended) of our nations’ hundreds of thousands of miles of roadways, literally killing lanes for pollinators and other insects. It’s a topic that I’ll soon be addressing in upcoming scientific articles.

Whatever Sherry’s reasons, I’m delighted and honored to have been asked to contribute to this lively online info-place exchange medium that is Grist Magazine. This magazine gives a unique glimpse into the daily lives, perspectives, and thinking of biologists, policy makers, activists, conservation biologists, and others. Thank you, Grist, for all you do.

When I took a break to write this final essay, it wasn’t from pulling insect carcasses off my vehicular sticky boards, although eyestrain was involved. I’d just spent more than an hour peering into my stereo binocular microscope trying to identify a medium-sized native bee that I collected earlier this year from another type of insect trap used in my research. It seems that bees, some flies, and wasps are attracted in amazing numbers and diversity to yellow, white, and blue Solo brand plastic picnic bowls filled with water and a few drops of dishwashing detergent, when set out on the ground. Little does the company know that they’ve created one of the most effective insect traps yet devised! I’m one of a group of a dozen or so scientists in the U.S. presently fine-tuning this collecting technique so that it can be used as a standardized sampling protocol for biodiversity assessment of our native bee fauna.

I twisted the micromanipulator resting on the stage of my microscope. It held the bee specimen so that it could be moved into any desired position. The wing venation on the dried and pinned specimen (sometimes I like to think of them as “shish-ka-bees”) came into focus. I knew I had a male bee since it had 13 antennal flagellomeres and no scopal pollen transport apparatus on its hind legs. Its long antennae told me it was likely a male eucerine, one member of a bewilderingly diverse group of bees, sometimes known informally as “digger bees.” These bees were formerly placed in the family Anthophoridae, but recently moved by the King Bee himself, Charles Michener of the University of Kansas, the world’s authority on bees, to the family Apidae. Finally, couplet after couplet, I slogged my way through the dichotomous key, thankfully a nicely illustrated one. It seems that my unknown bee belonged to the huge genus Melissodes, and not a related genus like Synhalonia or Tetralonia, others in the tribe Eucerini. It will take even more hours at my microscope keying it down to subgenus, then species. I longed for the days when the real expert, in this case the true eucerine master, Wally LaBerge, would have made these species identifications for me.

A fast-flying desert bee, Centris pallida.

Photo: Paul Mirocha.

We have a problem. It’s not easy to get bees, or any insects — except perhaps butterflies and large silk moths — identified to genus or species. Some scientists have rightly called this the global taxonomic impediment. How can we preserve the earth’s biota when we haven’t even given most of its creatures a scientific name! There are 4,000 species of native bee species in the United States alone. This always comes as quite a shock to audiences when I’ve mentioned this in public lectures. When queried, they usually can think of only 4 kinds of bees: honey bees, bumblebees, carpenter bees, and sweat bees, leaving plenty more literally flying under the radar of the general public. Sadly, there are probably fewer than 20 U.S. scientists who can identify almost any commonly encountered bee to genus and species. There is no equivalent to birding; there is no Peterson’s guide for bees.

All of these species perform essential yet unaccounted for ecosystem services including pollination, bioturbation, and nutrient cycling. There are nearly 20,000 described species of bees worldwide. In my own research I’ve discovered plenty of species new to science, without much effort. There may be as many as 30,000 bee species alive today. Some of them are already disappearing forever under the plow, swaths of invasive African grasses, or asphalt parking lots before they’re given a formal scientific description.

Although there are no field guides to bees of the United States, other than arcane taxonomic monographs, there are some pioneers exploring other ways to get the job done. Dr. John Pickering of the University of Georgia has pioneered an interactive computerized key utilizing illustrations and photos for use by naturalists, students, and scientists. Recently, his Discover Life project published a key to the bumblebees of the United States. A semi-automated approach is being taken by an Arizona and U.K. company called Morpho, Inc., which produces pattern recognition software (DAISY) for this task. In this system, the right forewing of an unknown insect is digitized and submitted to the program, which then performs the i.d. task. Thus, there is hope, even with a dwindling population of professional taxonomists, that the rest of us may soon have powerful tools enabling us to recognize our amazingly diverse guilds of native bee pollinators. Such tools should help ease the workload on museum taxonomists, freeing them from routine and boring i.d.’s of common insects, allowing them to get on with the heady task of describing new species, and revising genera.