Sunday, April 24, 2016

Trying to get summer underway.

One sign of winter shifting slowly into spring and summer is when we stop putting food in all our bird feeders. The feeder birds themselves are mostly leaving now, heading back up north. The big winter flock of American Goldfinches that inhaled our bags of niger seeds changed from their olive drab winter plumage to their lemon yellow breeding plumage, and have left us; of the even bigger flock of White-throated Sparrows, those that were already in adult plumage when they came down last fall, after entertaining us with their high-pitched whistling, have all left us for their breeding grounds. The hang-up is that the immature first-year birds have lingered behind, now themselves in adult plumage, but still living off my charity. "Get up there and get jobs and settle down, you malingerers!"

I stopped putting out sunflower seeds and they glared at me like they had been betrayed (and a few days later deserted me without a word of thanks).

Also living in our house on our generosity are the three or four species of ants that hang-out on our kitchen counters. Here, we are following E.O.Wilson's instructions: A woman after attending one of his lectures on the desirability and necessity of ants asked him afterwards, "Yes, but what should I do with the ants that come into my kitchen?" He said, "About once a week give them a teaspoon of tuna. They love tuna."

Well, they don't cause us any problem at all, and we were glad to see them dress up their marriageable girls in wings and send them flying off to meet suitable husbands and start new homes. They had a bit of a problem that they were inside a house, so every time there was a surge of new females, we had to keep slipping the window open to let them out into the greater world.

There are some moochers out in my study I don't feel charitable towards, and those are the dermestid beetles. When I find interesting dead insects or other small creatures I often bring them home and set them on a shelf in the study while I decide what to do with them. What generally happens is, they mysteriously turn into dust. For instance I found a dead mummified snapping turtle that must have died right out of the shell, because its body was only an inch long. It was a perfect little specimen.

It was too young to have many hard parts, and the next time I looked all its leathery parts were powder. If you look closely, you will see the many empty beetle pupal cases lying around it.

It turns out that not all the creatures I generously share my quarters with are ungrateful. I allow the cellar spiders to live in my study, filling the room with their billowing cobwebs. Today this one was eating a dermestid beetle.

One morning we found this elaborately complicated thing like a decorated cake on the side of our garbage can.

We knew what it was at once. It was the caterpillar of the butterfly, the Red-spotted Purple. The small cherry tree next to the garbage can had cranked them out all last summer, and they had hung their chrysalises from the cherry tree twigs, and we would often come by in time to see them eclosing, and holding to the empty chrysalis cases drying their wings. We hadn't realized before that they also came out in early spring when it seems like there would be little for them to feed on. This one had already attached its tail-end to the garbage can in preparation for shrugging off its larval skin to expose the chrysalis beneath. The garbage truck was coming the next day, and it would probably smash it up, so we separated it from the can and brought it in and let it attach itself to a stick, which we then put on the window sill in front of the kitchen sink. It immediately made its chrysalis.

We learned something: The chrysalis was one of those active jobs. If you saw it at night, it hung straight down.

If you saw it in the morning, it angled itself towards the east, to minimize its hanging shadow, which would give it away to a passing bird. In the afternoon it angled itself to the west.

After three weeks it emerged, and we put it out on the porch, and when the cool damp morning finally dried and warmed sufficiently, it was gone.

It is one of the prettiest of butterflies, and a day later we saw one of the prettiest of moths, a Luna Moth. Every time we see a fresh one, just out of its cocoon, we photograph it. How could you resist? But this one was the most beautiful we have ever seen.

In the really hot weather of midsummer, snakes tend to become nocturnal, so you don't see very much of them. The best time to see lots of snakes is in spring (when it is first warming up and they spend a lot of time on the move, and a lot of time basking), and in the fall. So far this spring we have already seen two rather neat snakes. The first one we saw (and it was the first time we had ever seen this species) was the Pygmy Rattlesnake, a beautiful little pit viper only about eighteen inches long.

Not long afterwards we got lucky again, and saw another seldom-seen species, Graham's Crayfish Snake, a watersnake that, as the name makes clear, feeds almost entirely on crayfish.

I think the natural year is off to a good start. To be ready, I have just bought upgrades on all my photographic gear. If I can ever figure out how everything works, I hope you will see an improvements in my illustrations.

Let me end this blog with a nice photo Cheryl took of a Gemmed Satyr, a drab little brown butterfly which has as its only claim to our notice, half a dozen little three-dimensional blue "gems" on its hind wing. This unusual individual had what resembled a setting of tiny diamonds around the gems.

Saturday, March 12, 2016

Sweating some big stuff for a change

Winter is sort of a down time for invertebrates, a dreary boring endless period I endure grumpily.

This winter was quite different.

In December we went out to the west coast for a big family get together. My sister, who lives in San Jose, and my niece, who lives in Berkeley, got together and rented a house right on the water in Pacific Grove which was quite lovely. We could see whales spouting right outside the bedroom window of our room, we could walk the beachfront path which went, if we had wanted, all the way around Monterey Bay. The wonderful Monterey Aquarium was a short walk up the road. Sea otters were abundant, almost every one a female with a young one.

We came back to Arkansas January first, and I was looking up some spiders in BugGuide when I realized for the first time that when I had a species up I could click on "data" and a map of the US came up and each state that had reported that particular species was filled in and the other states remained empty. The map gave a general and very useful idea of the distribution.

But as I checked through the different species, I noticed that, as in this map here, the Arkansas map was virtually never filled in, even though, as here, it is obvious from the filled in maps around it that the spider must occur in Arkansas. Of course what it meant was there was no one in the state specializing in Arkansas spiders, or at least no one (including me) who was reporting records to BugGuide. I was embarrassed for my poor state, which looked as barren of spiders as the South Pole. I checked, and I had photographs of about a hundred species that were blanks on the data map. I decided to literally put Arkansas on the map!

I spent the entire month of January sending them in one by one, and it was a real education for me (especially the ones disapproved as being either mistaken, or else as being part of a cluster of species that could not be told apart without dissection). So there was another month or more of winter gone by. Then we got ready and went down to Florida to visit old friends in St. Petersburg, and of course we visited the nice wetland reserves around the city. I had just upgraded my camera and lenses, and I thought I could get some practice using the new equipment by taking pictures of the long-legged wading birds that Florida has in such profusion.

Here, for anyone who might be interested, is an album of pictures I took down there.

Anyway, what I am leading up to saying is, we got back home, rested up a couple of days, and suddenly it is almost the middle of March, flowers are out, leaves are sprouting, birds are pairing up, I saw a couple of fresh orb webs showing up in this morning's dew. What in the world happened to winter?

Sunday, October 25, 2015

Fall trip to Tucson.

We left the house on the last day of September and drove out to Arizona to visit my son Gawain and his girlfriend Heather in Tucson. The monsoon was lingering late this year and there was tall grass growing along the roadsides as we entered the state, and the mountainsides were unexpectedly green. The sky was often cloudy for our stay, and we had occasional very heavy rains. The temperatures were comfortable, 80s by day (instead of 100), 60s at night. Afternoons and evenings and weekends we spent together, but during the day when they were busy with their work Cheryl and I were left on our own.

This was no hardship in Tucson and we spent beautiful days at our favorite places. For instance, the water conditioning plant with its acres of rich wetlands ringed with trails. This is a place mostly for birding (best, the day we went, was a handsome prairie falcon chasing killdeer around the waste ponds). Another day we went to Saguaro West with its many trails (we like walking up the dry washes), and we visited local botanical gardens, but over and over again we visited our favorite, Saguaro East, a thorn-forest wilderness that looks like a planted garden of desert plants and trees, each trail or dry wash passing through a different habitat.

It was a different time of year from our past visits so we were interested in what creatures we might see. Herps were interesting. Desert Spiny lizards we had seen before (they're fairly common) but this time they were more in the open and we saw them better. The particularly handsome local race is called Purple-backed Spiny Lizard. I like the way the yellow scales and blue scales meld into green scales down on the tail.

Because it had rained and there were some new surface puddles, the Red-spotted Spadefoot Toads were out. This was the first time we had timed it right to see them. In our walks we had caught glimpses of them disappearing down holes, but it wasn't until we visited our friends the Braddys on the edge of Tucson that we rescued one from their pool and so got to see it up close.

These little guys show one of the extreme measures amphibians can take to survive in the desert. A hard sharpened area on the inner edge of the inner toe on each leg (you can see the yellowish bump clearly at the base of the inside toes in the above picture) allows them to dig into the soil, where they remain for most of the year. When it rains, they are ready. They come hopping out and look for anything moving to put in their stomachs (this being their only chance to feed), meanwhile singing nonstop all night (this being their only chance to breed), then as quick as they can, they lay their eggs in every temporary pond, hoping their offspring can get through the tadpole-to-adult stage before the pond evaporates (in warm weather the whole process from egg hatch to metamorphosis takes as little as two weeks). Then everybody digs down into the soil to wait months for the next rain.

We also saw a couple of very nice small mammals. If you have walked through  the desert, you have seen packrat nests, a meter-diameter pile of old dried cactus fronds, other detritus, sticks and stones, anything else around that a small rodent could drag into the mix. The nests are obvious everywhere, but seeing the packrat that lives underneath (more correctly, the White-throated Wood Rat), is trickier. You aren't supposed to feed the wildlife, but we were eating our lunch, and before we knew it we had dropped a few large juicy grapes on the ground near a nest, which was enough to lure out the occupant. He was quite endearing, despite being, well, pretty ratty.

But the next animal we saw was the star of the trip. We walked around a corner of the trail, and a big animal went bounding off. Through the brush I saw a flashing white rump and huge ears.

"A deer!" I shouted at Cheryl, but I was already changing my mind. "Or was it a huge jackrabbit?"

Cheryl was a few paces ahead of me, and she saw it where it had come to a stop around the other side of a big bush.

"A jackrabbit," she said.

But it was quite unbelievable, an enormous woolly animal with a highly intelligent face, more like something from Alice in Wonderland or some other child's fiction. It was watching us with great interest. "I'm late," it might have said.

We had to wait for it to wander off before it would stick up its marvelous ears, and we could get a picture of them.

We looked him up: this was the Antelope Jackrabbit, the largest and heaviest of his kind. His name comes from the huge white antelope-like rump that he could flash when he was running away, probably to alert other rabbits in the vicinity that there was a predator approaching.

However this is meant to be a blog about invertebrates.

Just beyond where we saw the jackrabbit we walked up a rocky dry streambed and Filigree Skimmers were flying up ahead of us and landing on the next big boulder. These are fancy tropical dragonflies that don't come very far north of the Mexican border. A field guide I read said that identification was "unmistakable because of the wing pattern alone."

Another much commoner but equally unmistakable species of dragonfly was the Flame Skimmer.

It was near the end of the season, so many moth and butterfly caterpillars had reached their full size before pupating. Here are two butterfly species poisonous because of eating poisonous plants, first the Queen from eating milkweed, and then the Pipevine Swallowtail, from eating pipevine.

In keeping with the harsh desert scene, in addition to the poisonous species there were a number of venomous species (a neat distinction to keep).

This first caterpillar, though the photograph doesn't show it so much, looked so much like a lichen growing on this branch that Cheryl and I both passed it by, until Gawain called us back and pointed it out to us. It's a subtropical species related to our Io Moths, and like the Io Moth has spines that can sting you and raise a nettle-like rash on you if you carelessly brush against it.

  The next is quite interesting and one we have long wanted to find. It's a Puss Moth caterpillar, the name obviously coming from its hairy coat and what looks like a tail. If you brush against this one, the effects can be quite serious. "Sensitive individuals," says Wagner, the writer of our caterpillar  field guide, "who begin to develop systemic symptoms should seek immediate medical attention." We have heard of deaths occurring.

 In the last couple of years we have been mainly interested in learning something about spiders as a group, so we were particularly paying attention to the spiders. Mostly we were seeing here desert versions of species we have at home in Arkansas.

This jumping spider for example we are certain is Phidippus clarus, a familiar species at home, but here seemingly twice as big with its wide pancake abdomen.

And everywhere we found Green Lynx spiders (handsomer with a paler pattern than ours at home) clinging protectively to their egg nests, which they will continue to do all winter until they freeze or starve. Spiders are often quite good parents.

Most abundant was the Labyrinth Orbweaver, a species also fairly common in Arkansas. It is best known for weaving two separate kinds of webs side by side. First it has a tidy and typical orb web, round in shape with spokes radiating around it like a bicycle tire. And then, a little bit over to the side, it has a chaotic tangle of lines with no order to it (the "labyrinth"); perhaps these two webs each catch specific kinds of insects. A few lines connect the two webs to each other, and in between the webs the spider weaves a few leaves together to make a little retreat it can hide in if it's disturbed. That's how it does it at home, anyway.  Here is a typical Arkansas set-up with the orb web in the background, the tangled web in the foreground, and the spider itself in between in its refuge.

But in Arizona they do something different (this is our first season studying them, so perhaps those in Arkansas will do this same thing only a little bit later than the Arizona ones). In Arizona I did not see them in a little leaf bower, but rather, they began laying egg nests. Here is the first egg nest.

Here is a second. They are laid in a line, with the spider at one end. Notice how the spider resembles the egg nests.

The spiders keep on doing it.

And I think I get what their dodge is. At this time of year the mesquite trees their webs are located in or under all have their seed pods drying and ready to fall to the ground. The least breath of wind and there is a rain of these tiny strings of seeds. Frequently instead of reaching the ground, they are caught in a spider web. I think a hungry bird coming along and seeing this juicy spider with its nourishing eggs might pass it by thinking it is only a dry and tasteless mesquite pod.

Postcript added 26 October: After a comment made about the egg nests of the Labyrinth Orbweaver, I made the mistake of doing a little research, and what I find is, that the eastern Labyrinth Orbweaver, such as I see in Arkansas, Metepeira labyrinthea, is not the same species as I have just written about in Arizona. In fact there are at least five different Metepeira species in Arizona (numerous other species throughout the west), and only the eastern one should be called a Labyrinth Orbweaver, though the others are nearly identical in appearance and nest building and egg laying. This is why, I suppose, the one I photographed in Arizona might mimic mesquite seed pods when there are no mesquites in Arkansas. Everything is so much simpler in the east.

Friday, August 7, 2015

It's a jungle right here (if you're a frog)

Cheryl and I are addicted to the detective programs we get on Netflix and Google. The British ones are usually best but we also like the Swedish and Danish and Australian and New Zealand and Canadian ones. The same formulas run through all of them. Some woman is walking her dog along a beach, the dog digs in the sand and a bloody hand is revealed. Cut to the police there in their crime-scene suits, joking over their last bite of breakfast while the pathologist examines the cadaver. Special make-up people on the different programs compete with each other for the most gruesomely realistic split-open heads or maggot-crawling torsos.

Something like that is going on in our garden. We are out innocently looking for bugs and suddenly discover gory, half-eaten, and very human looking remains.

These are green treefrogs but we're not quite sure who the murderer is. Green treefrogs are murderers themselves, sticking to our windows at night to feed on moths attracted to the lights, or waiting under flowers for butterflies to approach. But they are also the main small vertebrate prey for just about everything else. Ribbon snakes for instance hunt them mercilessly and are probably their chief predator. But ribbon snakes swallow their prey whole, leaving no bodies behind.

Green treefrogs can hide or hop away, but they don't otherwise have many defenses against ambush or trap-setting hunters, no teeth or claws or poisonous skin . And, they are just small enough to occasionally become prey to invertebrates, which seems almost against the laws of nature.

For example, our backyard ponds are so dense with aquatic vegetation the surface of the water is not visible, and that vegetation is densely populated with day-roosting green treefrogs, but also with enormous black-and-yellow garden spiders, Argiope aurantia. I was observing their interactions last summer, and the spiders, after they were nearly full-grown, were feeding almost entirely on treefrogs.

But the spiders did not leave behind half-chewed remains either.

However, we had a clue. The very wet spring this year, which had led to an unusual number of treefrogs, and an unusual number of Argiopes, had also led to, we noticed earlier in the summer, an unusual number of Chinese mantises, and they had steadily been going through their instars, getting bigger and bigger. Here's one from the beginning of July, still a long way from adulthood, but already an impressive size.

This one looks like it is feeding on a roadkill skunk but it's actually a Milkweed Tussock Moth caterpillar, a creature that came out in the hundreds this year and chomped all our milkweed plants to the ground (after the Monarchs failed to come).

Now the mantises are molting into adulthood, four-inch-long giants that look fully capable of catching a treefrog.

Take a closer look at the spines in the powerful grasping arms.

So there was our prime suspect, an animal with a ferocious reputation and the tools to back it up. Finally we caught one in the act. We were eating breakfast and Cheryl looked out the window and said, "There's a mantis with a frog." We rushed out with our cameras. I suppose it would have been more in keeping with the crime programs if we had rushed out with our cell phones.

So, with the snakes and spiders and mantises after them, what is happening to treefrog populations in our backyard? Well, so far as I can see, it's not even making a dent.

Thursday, July 16, 2015

The month of June

When I step outside the house, even when its just for a moment, I try to remember to sling on my camera. If I don't I'm sure to see some interesting creature or bit of behavior that won't be there seconds later.  I often forget, but I often remember and get some of my best pictures. So when I recently glanced through the pictures I took in June, it was quick reminder of some of the neat things I had seen last month. Here are a few.

First, a Western Lynx Spider, a spider I was pleased to see because I thought they were strictly western and didn't occur in Arkansas. Lynx spiders are notorious for the long spines on their legs, but this one has what looks like an almost painful surplus of spines.

Except for its special status and comical spines it's sort of a dull little spider. By contrast here is a jumping spider, Paraphidippus aurantius, that is especially colorful, but very common. It has just caught a small katydid.

In folk wisdom here the very big crane flies we get in the spring are called Skeeter Hawks, and it is believed they hunt down and kill mosquitoes. The logic is obvious: they look like mosquitoes, but are way bigger. Actually there really is something here rather like a Skeeter Hawk. This very large and colorful mosquito (Toxorhynchites sp.) looks formidable to us, but in fact, as you can see by its droopy mandibles, this mosquito does not bite. It feeds innocently on nectar. But its larvae really and truly hunt down and eat the larvae of regular (i.e. biting) mosquitoes. Don't swat this one.

In a previous post I showed some of the courtship of the cellar spiders that occupy my study with me. The last picture I showed was of my favorite female with her new egg sac. I can add another step to the saga now, since those eggs have hatched.

I think they're kind of cute.

Paper wasps of the genus Polistes all die in autumn except for the newly mated young females who overwinter and start up new nests the following spring. Most of those nests fail. The new queen must chew up wood and turn it into paper and start a nest from scratch, often under the eaves of our house. They have to build a few cells, lay eggs in them, and when the new larvae hatch, go out and gather caterpillars to feed them, much like a bird bringing food to its nest. The queen sallying out for food puts herself in the way of several dangers, and if something happens to her, it is all over. Once she can raise the first few up to be workers, then she can remain safely at home laying eggs while the others do the work and take the chances. But it takes a long time to reach that point. Especially with our slow wet spring it was difficult to get started this year, and I saw several attempts fail. But there is one on the edge of a window around the side of our house I have been following.  Here she is, glaring at me for being a little too nosy.

The species I think is Polistes exclamans. The first few grubs have woven cocoons. She has started some new cells and put eggs in them. If she can just get past this moment.

A day later, an important event: She has a worker.

It seems to be a good year for moths shaping up. We were up at Ninestone in the NW corner of the state helping with a bioblitz. We put out a black light and this handsome Giant Leopard Moth was one of the stars of the evening.

A few feet away we found this spectacular Promethea caterpillar feeding on a tulip tree.

The next three pictures we saw during a visit to the central part of the state.

Here is a nice wasp-mimic moth, a Grape Root Borer. This male has got all his pheromone-producing equipment hanging out.

This might be the prettiest creature we saw during the month, a Meadow Purple-striped Grasshopper.

This might be the most bizarre, Rhomphaea fictilium, a spider that often lives parasitically in the web of another spider. The long thing hanging down is its abdomen, which is flexible and bends in the middle.

And, coming back home, this might be the most ordinary. It's a Corn Earworm. We get a lot of our produce from the local farmers' market, and I don't know about you, but I don't mind a bit getting a reminder that this is unsprayed organic food.

Now, tell me, he that knows: What do people who don't love bugs do with their lives?