A birdwatching friend, Herschel Raney, was also getting into bugs, dragonflies and butterflies especially. In fact, he was leading the charge on butterflies, doing the research, contacting authorities, searching species lists in old railroad surveys, and creating an online state list of butterflies with maps of occurrence and going out in the field and finding all kinds of species no one knew were in Arkansas. His house in Conway, in the Arkansas River Valley, was amazingly well located in a nexus between the Ouachitas, the Ozarks, and the Delta. Bell Slough WMA on Lake Conway, along with the adjacent Camp Robinson, together a large area mostly developed for wildlife, and containing every imaginable kind of habitat, was his center of operations. He invited us down to Bell Slough one day to show us Diana Fritillaries, a species we had thought an almost impossible rarity, but which at Bell, he told us, was fairly common.
So he found us several Dianas, plus Cobweb Skippers and Dusted Skippers and a host of other species we had never seen before. As he was showing off his territory he was walking along and reflexively flicking a finger at everything he saw and naming it. And at one point he said "bumble bee," and I opened my mouth for the first time that day and said, "No, it's a robber fly."
Which stopped us both in our tracks. We walked back a few steps and looked at this thing closely. It was a big hairy black and yellow insect that had all the marks of a bumble bee, but on closer examination it wasn't right. Instead of biting mouth parts it had an enormous beak sticking out in front. It was one of the bumble bee-mimicking robber flies, but how did I know that? I don't know myself, but since the time I was a kid growing up in Berkeley, California, I had known what robber flies were. How did I know? Who told me? Where did I read it? I have a clear memory of when I was, oh, ten years old, sitting in the backyard, doing one of my favorite stunts to gross people out: A mosquito was on my hand and I was watching it fill up, watching its abdomen balloon out and turn pink. And then I became aware of a small robber fly (I knew at the time that's what it was) sitting on my elbow and watching the mosquito. I held my breath. The robber fly made a high curving flight, a mortar-shell trajectory, and grabbed that mosquito and flew off with it. I was thrilled.
This time Herschel and I were both thrilled to look at this large fierce hairy fly, and I think we decided right that moment to begin studying robber flies. Herschel, in his usual systematic and fearless way got on the internet and immediately contacted all the top robber fly authorities in the world, immediately getting friendly replies and offers of help and masses of material that would be the absolutely necessary basis to help us get started. Among others, he contacted Jeff Barnes, the head of the arthropod museum at the University of Arkansas in Fayetteville, who by miracle turned out to be a robber-fly specialist, and that ended up being the greatest help of all. Throughout the summer we followed our various pursuits, but it was in our minds to begin in earnest next summer. For now at least we began noticing robber flies, ones that caught their prey then hung by one arm under a bush while they fed on it, or others that sat at the end of a twig, then sallied out after prey just like flycatchers, immediately returning to their posts. And of course, the bumble bee mimics, that seemed to come in several sizes indicating that they were different species. On November 30th of that year, a time when most insect life had come to a stop, Cheryl and I were walking down a trail in Craighead Forest Park when a smallish rather skinny black fly landed on her backpack. We studied it. It was a robber fly. It was a bit beat-up looking, no doubt because it had survived so late into the year. There was certainly nothing bumble bee looking about it, but the worn and thinning black hairs on its thorax had a sheen of yellow on them. It must have been one of the bumble bee mimics, we decided, perhaps a diminutive male of the species. Wow, it had almost lived into December.
For the next few years we got very serious about robber flies, and after much collecting, studying of specimens under the microscope, reading the various literature, and using our bird-watching skills, Herschel and I got so we could find and identify by sight just about every robber species in the state, and this came to a climax with our paper in the Entomological News, "Robber Flies (Diptera: Asilidae) of Arkansas, U.S.A.: Notes and a Checklist," by Jeffrey K. Barnes, Norman Lavers, and Herschel Raney. When we started, there had been some forty species recorded for the state. We brought that list up over a hundred. Along the way we caught several species of bumble bee-mimicking robbers flies, all of which came out in the spring and summer. But there was one species we didn't find in those early years, Laphria affinis, which we knew came out in the fall and early winter, and which I knew must have been that skinny fly we saw November 30th.
In fact, at the end of our first year of study, on November 30th, Cheryl and I had gone back to that very spot, and sure enough there was a yellow-and-black robber fly there, this time a big one, a fat female, and in my excitement I made a wild sweep with my net, and missed, and it disappeared for ever.
A few more years went by without seeing a single Laphria affinis, and then we learned of their addiction to fallen and rotten pine trees, how if the males want to mate, they have to wait on these logs for the females to come by to lay their eggs, and how the females have no choice but to come to the logs to lay their eggs. So now we find them easily, and we have learned that they are one of the commonest of the bumble bee mimics. And since in the past I twice found them November 30th, I have been attempting to find one just one day later, to get the only December record in the state for a robber fly. Each year when it got into late November I would watch the weather, hoping it would stay mild for just a bit longer, and each year when it hit December, killing frosts and storms came in making the month wipe-out.
This year I tried yet one more time. Late November had a few days where it got below freezing overnight, but not desperately low. And there were no terrible storms. On the other hand, there were heavy overcasts every day. What I needed was a temperature at least in the high 60s, better low 70s, and clear sunny skies. Well, December came in with dense clouds, but at least not bitter cold. December 1st and 2nd were no good, but the forecast for the 3rd suggested some clearing in the afternoon, and perhaps low 70s, and from then on cold and storms. This was it, that one chance on the 3rd.
We got up that morning and it looked very dark and miserable. It lightened up a bit by mid-morning with temps into the low 60s. I told Cheryl we would pack a lunch and go to Crowley's Ridge SP to a pine tree blow-down where we had seen two Laphria affinis a month earlier, about the beginning of November. We got there and walked up the trail to the area where we had seen them and quite magically the sky cleared, the sun instantly raising the temperature several degrees. We picked our way through the tangle of fallen trunks, and there was a male guarding his territory. He was very shy, but he flew up and timidly tried to drive me away, flying around by my head, and then he landed on my back. I held very still and Cheryl got a distant shot of him on my back before he flew. We thought he would disappear, but instead he curved around and landed on his log again facing me, and I got a distant shot of him. There it was, the record was recorded.
There is a very early-appearing robber fly that comes out in February, more than a month earlier than the next earliest robber fly. And now there is this one, coming out nearly a month later than any other. I sent Herschel and Jeff Barnes pictures of this Laphria, and said "Now, if anyone asks you how long the robber fly season is here, tell them you can find robbers in every month but January." Not bad for a state this far north.
And then it didn't seem like all that exciting a thing to be able to say, and I began to have a feeling of anticlimax. What am I going to do next year on the first of December? Probably sit home and read a book.
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