Monday, February 20, 2012
I knew this would happen
At the top of the page I have put, as a hopeful sign, a Spring Beauty out with a tiny Sweat Bee (Lasioglossum sp.) on it, but it has mainly been wet and gloomy weather.
A week ago, we had some actual wintry weather. In the middle of the day it started snowing. It was about 34 or 35 degrees, so it didn't seem like there was much chance of it sticking. In the next hour it got harder and harder. Now you could see sleet mixed in, the snowflakes still circling, but the sleet falling straight. Snow was beginning to stay on the ground and along the tops of branches, maybe a quarter of an inch. The temperature was still above freezing. I went outside and looked closely, and it wasn't sleet exactly, it was more like icy pellets. And then it began raining.
For most of you, seeing this might be mildly interesting, but I personally was getting panicky. I've mentioned before that I belong to CoCoRaHS, part of a nationwide network that reports precipitation with close accuracy using rigid procedures. I can't just say snow is falling, I have to give the depth for a twenty-four hour period, and the water content (I have to melt a sample size of snow and see how much water remains). I have to say how much the snow has settled the next day, and how much new snow is added to it, and the new water content measure, and keep doing this every day until the snow is gone. For people in the high plains and the upper MidWest where snow is piled up all winter there is nothing to it, they are used to it, they know the whole routine and just what box to record each part in. But for us down in the MidSouth, where we only get a couple of snows a year, we can't remember any of that stuff, and we have to keep retaking our on-line training course. It doesn't say a word about icy pellets. The director of the project, in his monthly reports back to us, is very witty at our expense discussing how we non-snowbelt people panic and get everything wrong.
We heard it raining all night. That was a terrific relief, it would melt off all the snow in a minute and we would only have to report how much rain was in the gauge. When I woke up next morning, I checked the thermometer first thing, and it was still above freezing. But when I looked out the window there was snow on the ground. How could that possibly be? I went outside and checked. It wasn't snow, it was all the pellets frozen together. Now how the hell do you report that?
A couple of days ago there was the promise of sun ("some cloudiness") and at least temperatures in the fifties. It was time for a real expedition. Cheryl packed a lunch and we took off for Village Creek State Park. It's the largest state park, about an hour south of us on Crowley's Ridge near Wynne. We had a goal: the first robber fly of the season, Nicocles pictus, comes out in the second week of February, at least a month before any other robber fly. Village Creek is the best place to find them. Robber Flies are my main insect obsession. They are big hairy predatory flies that operate like falcons. That is to say, they pick a spot (the end of a twig, the top of a bush, an open area of ground with clear sky around it) to wait, and when an insect flies over, they sweep up faster than the eye can follow, grasp the insect in their muscular spiky legs, stab it with their beaks loaded with neurotoxins and digestive enzymes, carry it back to their post, and suck its juices out. They often favor wasps and bees and other robber flies as prey, all dangerous things which they attack fearlessly. How can you not love them!
Here is a picture of Nicocles, which I have downloaded from my website (which you may click on over to the right here, if you want to learn more about this very special family of insects). Admittedly Nicocles is not one of the larger members of the group (the different species run in size from about 4 mm to about 50 mm, and Nicocles is probably about 15) but it has many interesting features about it, especially the fact that you can see one in February after not having seen a robber fly since last year.
When we set out from Jonesboro it was overcast, but the promise was for sun. Sun and at least some warmth would bring Nicocles out. Now Village Creek SP is a long drive down, and when you get there it has a bad habit of building up clouds in the afternoon. I recalled reading an article by a man who was studying the behavior of a certain species of robber fly which required him to sit and watch one throughout the day. He was out during a partially cloudy day and when it was sunny the robber went about its business, but whenever a cloud covered the sun, the fly dove headfirst into the leaf litter, and didn't come out until the cloud passed.
However as we drove, the clouds broke up then disappeared. The sun shone down and the thermometer on the car went up, low fifties and climbing. Then as we entered the park the clouds came from nowhere and enclosed the sky. There were still a few breaks, so we went quickly up to a high ridge trail on the south side that was usually a dependable place for Nicocles. We walked the trail hurriedly, watching the tips of twigs, but it was cold, and the sun was going quickly. There were loud buzzing sounds all around, often the first sign of robbers, but they were all a dark species of Flower Fly (Family Syrphidae), a species which we always see early in the year. They were on the path everywhere, but it was too dark and cold to see a robber.
In fact the day was steadily getting darker and colder, so we decided to return home. The round trip would be 125 miles. Here is where you discover if you have a genuine obsession for insects. We had driven all the way down here for the purpose of seeing a 15 mm-long fly. Not a new one; one we had seen many times before. If we had seen it, the day would have been a great success. Now that we hadn't seen it, we were guiltily aware of this extension of our carbon footprint, of this quarter tank of gas expended.
To get a little gain from our trip, we decided to do some exploring. The park is huge, and terrific for insects. After years of going there we were still discovering new paths. On this day we drove clear to the northern side of the park and found a bridle path we had never taken before and walked some way along it. It was a completely different habitat, and looked very promising for later in the summer. We would be back.