Wednesday, September 25, 2013

Frogs, toads, spiders, bugs, and a Spiny Oak-slug

I commented on an earlier post that we were overrun with baby toads. They are still around, often turning up in the middle of a picture when you least expect them.

But there are distinctly fewer. I don't know if that is just because they have distributed themselves more widely throughout the neighborhood, or if something is predating them. Not many things eat toads. When attacked they squirt out poisonous juices. If a dog bites one once, it learns its lesson, and never bites another one; if you pick one up I hope you know to wash your hands before you touch your eyes. However the other day I caught a glimpse of something disappearing into cracks in the wood of our raised beds and realized it was a baby Hog-nosed Snake. Though only about a foot long it flared its head and did its best to resemble a cobra/puff adder, and I was reminded that this harmless (to us) snake is one of the few creatures who not only eat toads, but specialize in them.

So if they have actually reduced the numbers of toads in the yard, that might allow the wolf spiders a chance to rebuild their decimated populations, EXCEPT now the yard is overrun by frogs. They are always here in summer, but not in these numbers.  Bronze frogs and cricket frogs are lining the muddy edges of our pond, and green tree frogs are lined up on the stalks of the pickerel weed, or plastered against walls, or doing their droppings on all our windows.

The reason you see them out in plain sight clinging to the sides of walls or high up in the aquatic vegetation is that they too have a deadly enemy who hunts them ruthlessly and is, itself, a skilled climber: The Western Ribbon Snake.

This past weekend we were at Ferncliff Camp west of Little Rock, where we teach a class in insect ecology every year, and we did a night op there, out with our headlamps looking for wolf spiders, and just as in our yard, we hardly found a one (though we found some other very good spiders). This is our first year looking closely at spiders, and it can be that wolf spiders are very common in spring and early summer, then thin out when the hot weather comes, which is why we are not seeing so many now. We'll need to do this for another year, so we can get a pattern for a full year. Anyway, perhaps we were blaming the frogs and toads unfairly. Recently a big fishing spider (Dolomedes triton), has been sitting up in the middle of the pond vegetation, holding its egg nest in a sunny spot to speed development. This is a spider that skims over the surface of the water, that dives under water when disturbed, and is able to catch small tadpoles and fish. Dolomedes are usually common in the pond, but I had not seen a one this year, and thought they also were a victim of the frogs, skillful hunters of invertebrates. But obviously they had been there all the time, hidden in the thick vegetation. Frogs, toads, snakes, spiders are here every year. Their varied offenses and defenses must average out.

Now what else did I promise for this blog? Bugs. True bugs, in this case, of the order Hemiptera. Along with aphids and hoppers and stinkbugs, this includes Cicadas, which are still loud on hot days, but are beginning to wind down. At this time of year you begin finding dead or dying ones everywhere you look. But they are still very noisy during the day. This has been a big year for cicadas. The loud calling of course is the male's way to get the attention of the females. But it didn't occur to me that I have never, for some reason, observed cicadas mating, at least it hadn't occurred to me until I looked down at my feet one day and saw a two-headed cicada.

Fulgorids in the tropics are huge bugs with big sort of helmet-like structures over their heads. In this country there are a couple of dozen species but they are all puny things that look sort of like miniature cicadas, none of them more than 10 mm long. In late fall of 2007 we had turned on our porch light to attract moths, and when we checked there was a bug on the light that was somewhat like a small cicada but that we quickly worked out was a fulgorid. Only, it was 20 mm long. We sent it to BugGuide, and even Andy Hamilton, the expert on these creatures, was puzzled. The one we saw on the light was on the ground dead the next morning, plus we found a second dead in a spider web. We collected these and sent them off to Andy. He had identified them in BugGuide as Poblicia texana, but in a note added "Now that I have seen some specimens, it is my opinion that this is probably not the correct genus for this curious species--in some ways it looks more like the tropical genus Hypaepa."

In BugGuide now, there is a specimen from Mike Quinn from clear back in 1988, plus he submitted a nymph from 2010. Someone else has a Texas record from 2009, and there is a Georgia record from 2011.

We actually had another attracted to the same porch light in 2008, a year after our first one, but didn't report it to BugGuide. Yesterday I again found one on our porch, this one tangled up in spider-webbing. I untangled it and kept it overnight. It was fine when I released it. I guess we will report this one to BugGuide, since it is the third time on the same porch. Here are some pictures of it.

And now, the promised Spiny Oak-slug. If you have studied moth caterpillars at all, you will have learned that not all caterpillars look like caterpillars. There is a group called the "slug" caterpillars. Along with their slug-like shape, and the fact that they kind of ooze along the ground, they are heavily armed with toxic spines and often bright colors to warn you that you touch them at your peril. There are several different species. It is always fun to find one.