Field Notes from the Arthropod Hunters

The 'Arthropod Hunters,' Drs. Matt Bertone and Nancy Brill.

My co-worker, Dr. Matt Bertone, is an insect ID expert on-board the project. We begin the day by packing up our collecting supplies and driving to homes, mostly located in suburban neighborhoods, within a 30-mile radius of Raleigh. When we show up at the homeowner’s front door, they smile and seem so genuinely excited to see us. And maybe a bit apprehensive, too.

“I’m anxious to see what you find…or do I really want to know?” the homeowner asks with a nervous laugh.

“You can be as involved as you want,” we say, as we gear up for a 3 to 4 hour collecting experience and explain what we’re about to do.

And we’re serious about collecting. We collect insects that may have been dead for years because we’re hunting in places the average person may never see or bother to clean — where even during a bright sunny day with all the lights on in the home, I still need a flashlight to comb the floor and walls. I don’t want to leave behind a single specimen, many of which look just like a speck in ‘Whoville’ to the untrained eye. We crawl on our hands and knees, wearing construction-type knee pads and spelunking-type headlamps being careful not to knock anything over, as if all the owner’s belongings were Lladro figurines. We attempt to maneuver our way around and underneath unsteady end tables and other furniture with the coordinated stealth of James Bond.

Then suddenly, while I’m collecting in the upstairs bedroom, I hear Matt burst with excitement from the first floor at the discovery of a dead, 4 millimeter long inconspicuous fly found in a windowsill:

“Oh, this is great – a new species we haven’t found yet!  That makes 12 so far.”

As I approach with curiosity to take a look, the homeowner asks a bit puzzled, “Are you just as excited as him?”

Yes, I am.  Up to 12 species of flies found on just the first floor – that’s AMAZING!

These discoveries sometimes lead to understanding human behavior or the natural history associated with our findings.  Lace bugs, minute pirate bugs (Anthocoridae), Neotephritis fruit flies, and aphid exuviae found on a shelf or windowsill probably meant there were cut-flowers in the home at one point. Curiously, the variegated mud-loving beetle (Heteroceridae) we found inside the light of a dining room chandelier tends to be more associated with muddy banks and streams than homes.

“There’s a ditch close to my backyard,” the homeowner said, offering a likely possibility for the source of the beetle.

And once in a great while we perform entomological diagnostics.  One owner, whose house was situated far back into the woods, pointed to his legs:

“I’ve been getting these bites lately on the lower half of my legs whenever I go outside…what do you think it is?”

Unfortunately, our training does not include medical dermatology, but many times our discipline crosses over into other areas of science.

“Are they small, red bumps?  And do you only get them when you go outside?” Matt asked.  The man nodded.“It could be seed ticks,” Matt said and suggested an over-the-counter preventative spray.

The stay-at-home moms and dads are excited for us to show their kids what we do and what we find.

One mom enticed her boys away from video games: “Listen to what the scientists are saying.”  Ants, flies and cellar spiders held their attention for a few minutes before they returned to their games.

I crushed an odorous house ant (Tapinoma sessile) to demonstrate the smell to an excited five-year old, who then proceeded to squish every insect he found, including a live lightening bug from outside.  “Oh no!” I said, “Let’s not crush all the bugs.”

Left: An odorous house ant (Tapinoma sessile) is a common invader of our homes, often looking for water and food scraps. Right: Variegated mud-loving beetles are usually at home in burrows that they create in muddy stream banks; they are attracted to lights, however, and sometimes become trapped in homes. Photo credits: Matt Bertone

A four-year old helped me collect flies off the windowsill and carried a flash light around the house the rest of the afternoon assisting our search.  One mom left for a few minutes to pick up her second-grader at school so he could learn about what we were doing.  When they returned, there was a silverfish out of my reach in a closet so I handed him the forceps.

“I got it!” he said, proud that he could help me. Eventually his mom said she had to take him back to school.  “But I don’t want to leave,” he said. I helped him spell the word “Diptera” on a piece of paper so he could show his teacher that he learned the order of flies.

In one house we had an unusual discovery.  “Nancy, check this out!” Matt exclaimed, pointing to a jumping bristletail (Microcoryphia) inside the glass bulb that covered a light in the middle of the kitchen ceiling. How does an insect without wings, normally found outdoors, get into a light in the middle of the ceiling? We guessed it could’ve crawled into the house, up the walls, and through the electrical opening that led to the light. We’ll never know for sure what led to this insect’s death in the light dome covering, but it’s also a find we never expected.

Left: A "wild" jumping bristletail (Microcoryphia) in a Raleigh forest. Right: Venturing into a kitchen light leads to the unfortunate death of a jumping bristletail - how did a normally ground-dwelling insect even get up there? Photo credits: Matt Bertone

After 3-4 hours of collecting we’re thirsty and our foreheads glisten with sweat, something I’m slightly embarrassed about because we’re collecting in air-conditioned homes and I’m used to working in the heat outside. I never anticipated that home-collecting could be physically exerting. But, like I said, we’re serious about collecting. The homeowner offers us tall glasses of ice water and we drink, bottoms up in two minutes.

We line up the small vials of arthropods in alcohol when we’re finished.

“Ok, ready to know about what we found?” we ask the homeowner. Usually, they look at the vials witheyebrows raised, unsure how much we find is good or bad.

These vials of silverfish, carpet beetles and cobwebbed-trapped flies that are tangled together in the alcohol are what our investigation of arthropod diversity in homes is all about – discovering the unknown right under our noses, in the places where we spend our daily lives. We, the arthropod hunters, and citizens of science, learn something new every time we collect.

“Thank you,” the homeowner says, as we prepare to leave. Grateful that we didn’t find bed bugs or German cockroaches, the people who volunteer their homes for arthropod collecting seem relieved after we show them what we found.  “I can live with all that,” they say.  And they do, literally.

Dr. Nancy Brill’s primary research focus in Entomology has been in sustainable agricultural pest management. Nancy’s experience with agricultural production comes not only from her research, but also from working at a local farm in her hometown in New Jersey for many years prior to graduate school. She also owned her own business selling plants and vegetables at local farmers markets. Nancy has two daughters and is an advocate of career women (and moms!) in science and agriculture. When Nancy is not on a tractor or busy with her kids, she enjoys freelance writing, baking, and reading.