Wild Side: Sometimes no-kill insect studies don’t work

A properly curated insect collection may be valuable for decades, or centuries.


A lifelong lover of wildlife of all kinds, I avoid killing anything. I brake for turkeys and squirrels; spiders, and stinkbugs, and crickets that turn up inside our house get reintroduced to the great outdoors. Even ticks and mosquitoes generally get a pass unless they’re actively trying to bite me.

So for many years of otherwise serious insect study, I resisted embarking on the standard scientific method of collecting: capturing, killing, and preserving specimens for study. Partly, I was daunted by the logistics of maintaining an insect collection. But more fundamentally, I just didn’t like the idea of killing the things I was trying to learn about.

Starting 12 years ago on a study of Vineyard grasshoppers, crickets, and katydids, I decided early on that I’d rely on nonlethal methods — directly observing subjects, photographing them in the field, recording their calls — to learn about and document what occurs here. I simply couldn’t imagine killing and pinning these fascinating and oddly beautiful creatures.

It worked pretty well. Relatively large insects in a group with relatively little diversity, Orthoptera proved challenging but workable to study in those ways. But I’m finding that this was a special case: The main objects of my attention these days, bees and flies, can be fiendishly difficult to ID even when you have a specimen under a microscope. Trying to ID them without a specimen in hand is often utterly hopeless.

So, reluctantly, I’ve begun learning the skills needed to assemble, curate, and use an insect collection. I still cringe a bit every time I kill a specimen. But in spite of that, I’m finding the process of collecting insects to be surprisingly rewarding and even — dare I say it? — fun. A bee’s anatomy, viewed at 30 times’ magnification, becomes a stunning landscape of color and texture. And there is something enormously satisfying in knowing with certainty what species a difficult bee or fly belongs to.

Inseparable from the idea of collecting is the responsibility for preserving what you’ve caught. Insect specimens need to be kept in a relatively dry environment, preferable with constant, moderate temperature, to prevent deterioration or the growth of mold. And they need to be protected from hazards like carpet beetles, which feed on detritus of all kinds, are astonishingly deft at making it into even allegedly sealed boxes, and can rapidly turn a collection into a pile of exoskeleton flakes and random legs.

But properly kept, insect specimens can last for decades or even centuries, furnishing future generations of scientists with a body of information that simply can’t be preserved any other way. So I’ve committed to checking specimens periodically, refreshing the moth flakes I use as a fumigant, and housing my collection indefinitely in a dehumidified setting.

Equally important is maintaining information. Starting at the moment you capture an insect in the field, certain data — date and place of capture, identity of the collector, and ecological information such as what flower a bee was visiting when collected — need to be rigorously associated with each specimen. I typically collect bees using plastic vials, writing the critical information on the outside of the vial with a Sharpie. As soon as possible, each specimen is assigned a unique catalog number, and its associated data are logged in a spreadsheet.

Later, when each specimen is cleaned, if necessary, and pinned, tiny labels printed on archival paper with collection and ecological information are stacked on the pin under each insect. A so-called “determination label” can be added once a specimen is identified, giving the genus and species, the authority who defined that species, and the name of the person making the identification. If all goes well, a biologist a century from now will know to the day and within a few meters when and where each of my specimens was collected.

Handling specimens in the lab is, for me, the fun part. Pollen-caked bees can literally be coiffed, sloshed around in dish detergent and then blow-dried; a properly washed specimen shows all its colors and body parts clearly, and features well-fluffed body hair. They become objects of great beauty.

Pinning can be a challenge: Bees tend to curl up tightly when they die, so you need to carefully straighten them out, and for a bee only a few millimeters long, getting a pin through the right part of the body requires patience and dexterity. But working with specimens is an incredibly effective way to learn your insects, and time spent in the lab often translates into an ability to ID insects even in the field.

Collecting insects is not something to be undertaken casually. Careless handling, poor data management, or haphazard storage quickly reduce specimens to meaningless debris. When I take the life even of an insect, I feel a responsibility to make sure that life wasn’t wasted. But in spite of my initial reluctance, that responsibility feels rewarding rather than burdensome.