Friday, May 11, 2012

Scatter Creek

Cheryl was doing something, so I took off by myself.

I was heading for one of our favorite portions of the Scatter Creek WMA, to the north of us in Greene Co. The last time we had been there I had caught a glimpse of, and got a poor photo of a species of grasshopper that was unfamiliar to me, and I had been waiting for a chance to go back and try to get a better look at it. The path on the way to this grasshopper was also a very good one to see large numbers of Hairstreaks. (This is how I justified the carbon footprint to myself. People marvel at birders driving across the state to see a bird; we insect people drive across the state to see a bug!)

Grasshoppers are divided into three major groups. First come the Slant-faces. These are mainly small species that hide deep in the vegetation. They are characterized by their slanting profiles. The second big group are the Band-wings. These tend to be largeish grasshoppers, with long wings often in bright colors, red, yellow, blue. When they suddenly fly up in front of you, if you are not used to them, you may mistake them for butterflies. The third group, the Spur-throats, characterized by a little sort of bump in their throats, are medium-sized and miscellaneous in appearance and behavior. The one I was after this day was a Slant-face, which I believed would turn out to be a Velvet-striped Grasshopper, one of the species which should appear in Arkansas, but which I had missed last year.

I parked at the entrance of the wildlife management area. It was on the western edge of Crowley's Ridge, so I began my walk on a road that went straight up to the highest point on the ridge. I then walked a couple of miles along the ridge trail. There were Banded Hairstreaks on territories all along it. I tried to get a good look at each one in case there was something special. I finally spotted one that was different. Not a rarity, but a nice one anyway, a Striped Hairstreak. I'll put it up here next to a Banded, to give you an idea of the marks we look for. On the Banded there is a big blue square down at the bottom of the wing. The first difference to note is that on the Striped there is a big orange cap on top of that blue spot. Then next you will note that it has a lot more stripes.

There it is, simple as that. I hope I will eventually have some rarer species to show.

At this point, as almost always, a bit of serendipity intervened. I had been seeing a lot of Plains Yellow-winged Grasshoppers along the trail, a common spring species. This is one of the Band-winged group, and one that I had seen last year. But one I had missed last year, and a close relative of the Yellow-winged, is the Sulfur-winged Grasshopper. I had seen them for the first time recently at Petit Jean in the middle of the state, and gotten a rather unsatisfactory picture to put on my grasshopper Picasa Web Album. I assumed they only occurred in the western part of the state, but suddenly there was one here in front of me on Crowley's Ridge, and he posed for a number of pictures. I was beginning to notice something about their behavior. They (or at least the males) seemed to sit with their abdomen hanging down, so that it's bright yellow coloring showed, along with the stripe of yellow down their back. One suspects this is to be attractive to the opposite sex. In the event of a predator coming by, they could lift the abdomen up, it would be concealed under the wings, and they would disappear into the substrate.

I felt a bit relieved to have this good luck, because finding that fugitive Slant-faced grasshopper concealed in all the tangle of vegetation would not be easy.

I walked to the end of the trail where it came out onto a pine barren, which was the hot spot for grasshoppers.  I was immediately startled by an Orange-winged Grasshopper taking off at my feet and flying off with its brilliant wings. There were several of them in the more open areas, and I had to try to check each one by getting directly overhead and looking straight down on them. You see, there is a species I have never seen, the Coral-winged Grasshopper, which should occur in Arkansas, and evidently looks exactly like the Orange-winged. The way you separate them is, the Orange-winged has blue at the base of the inside of the hind femora, and the Coral-winged does not. It's relatively easy if you have a net and simply catch each one you see and examine it in your hands. It's trickier, but quite possible, however, to do it photographically. These all turned out to be Orange-winged. Here is an example.

(This species comes in a green and a brown form. I believe I showed the green form in a previous blog.)

I now began a careful search of the area where I had seen the Slant-face previously. I saw a few other species of grasshopper, but not that one. Though there was no water around except for a couple of seeps, there was a rather attractive damselfly flying along the sparsely vegetated ground, with the rather attractive name of the Springwater Dancer.

On a cherry tree I saw a small brown moth which I recognized as the moth that laid the eggs that gave rise to the defoliating Eastern Tent Caterpillars. This one, to judge by its furry antennae, was a male, perhaps waiting there for females to come by, since the cherry is their caterpillar food tree of choice. If so, he must have been doing very well, because the tree was covered with the eggs of this species, in hard-coated egg nests that circled the branches, and which would remain all summer and winter, until the caterpillars came out in their hundreds next spring.

There were lots of butterflies and other insects around, but the Slant-face I had come for was nowhere to be found. Well, what the heck, I had found the Sulfur-winged, and that was just as good. So I turned around to head back to the car, and there it was sitting on the path in front of me. A very nice one, and it even stayed to pose for me, and it was indeed the Velvet-striped Grasshopper.

So there it was; I had achieved all my goals and more. I got back to the car and, if only I had left things alone, but no, I took a quick check around a grassy area near where I parked. There was a tiny Slant-face, sneaking around in the vegetation. I was on my hands and knees following it. I couldn't get much of a glimpse of it, and I had no idea what it was. I finally managed to get a quick shot of it, but from nearly head-on, and from below, an angle from which I could see no helpful fieldmarks. Then it disappeared forever.

Now I'll have to go back and look for it.

Tuesday, May 8, 2012

Trying to keep up

In the spring new stuff is coming out every day, and I think, Ah, a lot of new stuff to report in my blog. But then, a lot of newer stuff comes out, and instead of writing about it, I go out and find a lot of even newer stuff. By the time you get a chance to write about last week's new stuff, it's old news.

So, for whatever value it still has, on May 1st around the house we saw these poor caterpillars in their first instar, the remnants of the eggs they hatched from still on the leaf near them. They are Prominents of some kind, but too small to guess the species. I measured them, and they are barely 5 mm long. This will show you what caterpillars are up against: If you look closely, you will see they are already covered with eggs of what must be a very small species of parasitic Tachinid fly. (Fair play: This is what Tachinids are up against: When I looked the next day they were all gone, eaten perhaps by a bird.)

Other sightings around the house: This quite wonderful jumping spider mimicking an ant. His steady exploratory walking was exactly like an ant's. He walked on his last six legs, and waved his front legs in front of him like antennae. Even the shape of his abdomen is lumpy to resemble the the multiple gasters on many southern ant species.

An obvious question is: Why does he imitate an ant? Well, I suppose ants don't have much meat on them, and probably taste like formic acid, so not many things eat them. That might be a kind of defense. And some ants bite and sting; that might discourage predators. But the possibility I like best is, some ant-mimic spiders hang out next to a line of ants, looking as much as they can like one of the guys, and then pop in and grab one when no one is looking.

The spring Robber Flies are mostly in by now, and the earliest summer ones are showing up. For instance, May 1st we suddenly had a number of Atomosia puella in our yard. You only notice these if you are an enthusiast. Some Robber Flies are almost two inches long, but Atomosia is at the other extreme, at 6-8 mm. If you aren't deliberately looking, you miss them altogether. They nevertheless have a lot of personality. If you see one, you will probably see several in the neighborhood. They sit, head down, on the walls of you house, on telephone poles, tree trunks, or other upright, preferably wood structures, and fly up constantly and bring back flying aphids or termites or tiny flies. They surprise you by pointing out how many tiny things are constantly in the air. The females do most of this bug-catching. The even tinier males spend their time doing hovering courtship flights about an inch away from the females. Here's a female on the side of a treetrunk eating some tiny thing while a male hovers hopefully nearby:

May 2nd we went up to Crowley's Ridge State Park in Greene Co. and walked a trail where, if it were going to be a Hairstreak year, they would show up first. And it was teeming with them, males sitting at the tip of every bush we passed, constantly flying up to dog-fight with the male on the next bush, sometimes three or more swirling around and around before returning to their perches. It was going to be a Hairstreak year.

We checked every one of them, but they were all Banded Hairstreaks, the commonest species. But other people around the state were beginning to find more unusual species, Oak Hairstreaks, White M Hairstreaks. No telling what might eventually show up, perhaps the hard-to-identify Hickory Hairstreak, or the rare Edwards's Hairstreak, or, if we get down to the southern part of the state, the King's Hairstreak. Here's the Banded. All the others will be some slight variation on this standard pattern.

Another butterfly was evident: An American Lady was laying eggs on the cudweed along the edge of the path. We looked and finally found one of the very attractive American Lady caterpillars.

There were also some spring Robber Flies along the trail, several mating pairs, for instance, of Machimus virginicus, one of a number of species in the Machimus genus. This one is identified by having only a tiny amount of orange at the base of its tibiae.

Best of all, we found a Neoitamus flavofemoratus sitting quietly beside the path. The diagnostic mark for this genus is that the hair on the back of the head curls forward (very stylishly). I had long wanted to get a close-up picture in just the right position to show this. This one posed beautifully for us (Cheryl holding my hat behind it to create a little contrast).

Thursday, May 3, 2012

Mourning Cloaks, again

Everybody in Arkansas is talking about the Mourning Cloaks.

I guess I should say, Everybody, in the subset of .01% of Arkansans who notice insects at all, is talking about Mourning Cloaks. I mentioned in an earlier blog seeing an unusual number of beat-up over-wintered Mourning Cloaks out displaying for females in the early early spring. That's the time you normally see them, and then you're lucky if you see another one all summer. But this new generation that the over-wintered ones gave birth to has been unusually present and noticeable. We have one that's almost a pet, feeding daily at a sap drip in one of our oak trees (we didn't notice till we downloaded the pictures we took of him that he was sharing the sap with crowds of fruit flies).

(Who can resist taking pictures of these beauties. I like the checkerboard eyes of the side-view shot.)

This past weekend we went up to Petit Jean State Park for the Spring Meeting of the Arkansas Audubon Society, and walked our favorite Seven Hollows Trail. There were Mourning Cloaks all along the trail, as indeed we had been seeing them everywhere we have been lately. It is quite extraordinary. I suspect it is a combination of the very mild March weather with a decent amount of rain in the early early spring to get all the vegetation going. In fact there are signs of a terrific butterfly season coming (if it doesn't get derailed by what may be a drought shaping up). We noticed, for instance, along the trail, an unusual number of Dainty Sulfurs were already out (often we don't see a one till late in the summer).

Also April 27th along the trail we saw our first Banded Hairstreak of the year, about a week early.

Hairstreaks are tiny, fast-flying, colorful, sometimes tricky to identify, and the majority come out (if they come out at all) in the month of May. They are to butterfliers what warblers are to birders, pretty to see, with always the chance of a rarity. We are due for a good year. We will know in another week if we are going to have one.

We didn't ignore the moths.  Cheryl spotted a big Virginia Creeper Sphinx Moth, invisible in the dead leaves until she pointed it out.

And a friend found a dead Io Moth, bright and beautiful, and brought it to us to I guess immortalize in a picture.

We found an elaborately woolly Yellow-haired Dagger Moth caterpillar.

And then we found this moth.

It seemed to us about as ragged and nondescript as a moth could be, a drab example of why I personally only pay attention to large spectacular moths (though I love moth caterpillars). In other words, it was perfect to test out a new field guide we had just purchased, the brand new Peterson Field Guide to Moths of Northeastern North America, by Beadle and Leckie. We have for years been using the 1984 Peterson moth guide by Covell with varying degrees of frustration. It's the old-style guide based on pinned specimens with the forewings raised above their natural position, and looking very little like the moth in life. It was designed for collectors who pinned their own specimens, then looked in the book for a pinned specimen to compare it with. Since we work with photographs of live specimens in their natural resting positions we practically have to stand on our heads and look under an armpit to get one wing in the field guide in the right position to hold up to our picture of a live moth.

Well, in the three decades since the first book, everything has happened. We now have digital cameras. We can point and shoot and get pictures that formerly required a studio and expensive equipment, and collecting (except for biologists) is going out of style, replaced by making photographic records of  live insects in natural postures. We have guides in this format for butterflies, dragonflies, tiger beetles, caterpillars, and finally, the new Peterson moth guide. To be short, we found (fairly easily) that our moth was a Ruby Quaker. It was on a page with only four species on it, in full color, showing the natural resting position, and examples of different color forms. We could not have found it in the old book, where it is located on a black-and-white page of twenty-one obscurely patterned pinned moths.

Both books cover about the same number of species, about 1500 out of the 11,000 species found north of Mexico. A slight disadvantage is, the old book covered the entire east, and the new book covers only the north-east. But the cut-off line for their coverage map is the Missouri-Arkansas border, so I expect we can find most common widespread species (and of course, we can keep our old book on the shelf next to the new one, as backup). The real test will come later this year, when the Underwings come out and I begin my annual struggle trying to identify them.

I'm very fond of Robber Flies, predatory flies with the behavior of falcons, flying up and snatching other flying insects out of the air. I have a Robber Fly web site which is designed to be a field guide (in the new, natural-position, style), and I am constantly trying to add to or improve on my photographs in the site. There is one group of robbers in the genus Machimus, which are all smallish, dark, very similar appearing flies, except that the legs are marked differently. There was one species in the group, Machimus sadyates, that I had never managed to get a good picture of, and suddenly here was one down on the path posing for me. This species is marked by having black femora (the first long joint of the legs) and orange tibiae (the second joint.)

Late last spring we started from scratch trying to learn the Arkansas grasshoppers. We did pretty well, but we missed some of the early spring species, and this year we are trying to find them. Last year we saw a few examples of the Plains Yellow-winged Grasshopper, a species which shows bright yellow wings when it flies, but otherwise is rather nondescript. This year we have seen several, and got some better photographs of them. We found a few on the Seven Hollows Trail.

But what we were really hoping for was another spring species, a very close relative, called the Sulfur-winged Grasshopper, one we had missed last year. According to the books, it looks more or less like the Plains Yellow-winged, except that it has a line of yellow down the middle of the back. When we got almost to the end of the trail we began seeing them, visible from a long distance through binoculars because of that yellow stripe. But they were so shy we couldn't get within twenty feet of them before they flew off into deep grass and disappeared. With all my stalking skills I had no luck getting my camera close till we saw a poor individual which had lost both of its hind legs (they readily let their legs go to get free of a predator, just as  lizards do with their tails). Perhaps that slowed it down enough that I got close to it for a picture. This is so far the best photo I have of a Sulfur-winged Grasshopper. It does at least show the yellow stripe down the back.

At the end of the weekend when we were driving back to Jonesboro, we stopped to eat lunch at Camp Robinson, east of Conway, and parked by the edge of Lake Conway. We noticed the cattails there were full of Cattail Toothpick Grasshoppers. These are comical insects we always enjoy seeing, their bodies long and slim to slip around behind cattail leaves so you can't see them.

We hadn't been there long before we realized some pretty frantic reproductive activity was going on.

A pretty good trip.

Oh yes, we saw some birds and friendly people.