Monday, April 24, 2017

The Life History of the White Furcula




It's probably not an exaggeration to say that the majority of meat-eating animals (taking into account, not just tigers and lions, but all the parasitic wasps, birds, spiders, parasitic flies, and so on) feed primarily on caterpillars. The caterpillars didn't get a vote in this, so they have concentrated on creating millions of ploys to avoid being eaten.

For instance, some caterpillars have learned how to eat poisonous plants without themselves being poisoned. Instead they sequester the poison in their tissues, so that whatever creature tries to eat them will be poisoned. Others have venomous hairs or spines on their backs so that whatever creature mishandles them will be stung and even killed. Other caterpillars look exactly like a gooey revolting bird dropping which no one is interested in eating. Or they might get two large false eyes on their back and look so much like a snake head that a bird that suddenly spots one nearby in the leaves will fly off in fright. The commonest, of course, is just to look so much like the leaf they are sitting on that they become invisible.

Well, those are all familiar ploys. The caterpillar of the White Furcula moth provides some new ones.

First, let's straighten out some anatomical matters. A moth caterpillar is essentially a mouth  with a huge vacuum-cleaner bag behind it which it constantly stuffs with food in order to grow as fast as possible (before it becomes one of the vast majority that get eaten). If you look at the first picture above, you will see that the dark area low down where the head is (on the right) has three slender reddish pairs of legs which will be its regular legs when it converts into a moth. Behind them are four pairs of round fat elephant legs, to support its long body that trails behind the "real legs." These are prolegs, that work fine as legs, but will disappear when the caterpillar develops into a moth. Most caterpillars have these, followed by a gap, and then at the tail end, one more pair of prolegs. What has happened here is that the furcula caterpillar has converted these into two long tentacles that it normally carries behind it (see second picture), but that when approached by a predator, it can pump fluid into to extend their length almost double.

What it does then, which you must see to believe (which you will see in the next series of pictures), is, it faces the approaching predator (in this case, my finger), throws those tails up over its head, extends them as long as it can, then slaps them down on the ground in front of its head (actually making a sound you can hear from a few feet away). It has very much the appearance of a scorpion striking its venomous tail down, and a small predator might very well move away, thinking it got off with a close call.




Now that little trick, pretending to be dangerous when it is actually harmless, and constantly eating, may get the defenseless caterpillar through this perilous period of its life as fast as possible before something catches and eats it. But there is still a serious hurdle to get over. It must spend many months in a cocoon changing from larva to adult, a time when it will be even more defenseless, even more slow moving, in fact not moving at all. Now every caterpillar faces this, and there are a number of dodges they use to get through it, maybe buried underground or under the leaf litter or camouflaged as chip of wood or a dried winter leaf. The furcula does this in its own way.

As you might have noticed, the White Furcula caterpillar comes in two color phases, green like this one we photographed in the wild doing its scorpion trick, and the yellow phase we photographed at the beginning of this blog, a different individual, which we brought home with us because it looked full grown, and we thought it was close to making its cocoon, and we wanted to watch the process.

Sure enough, after about a week it flattened itself against a narrow stick which was about its own diameter and spun a thin cage around itself, thin enough that we could still see it inside busily continuing with its spinning.


After several hours it had woven enough silk around itself that the cage was now opaque, and had somehow taken on the color of the stick.


And here is how (if we had left it outside) it would have spent the winter, hiding in plain sight disguised as a little thickening around a stick. We kept ours in a jar (just in case its trick didn't work) out in the unheated garage, knowing that it needed to experience some freezing temperature in order to complete the metamorphosis pattern and emerge at the right time. It had made its cocoon August 19, 2016.

Once it warmed up in spring, we moved the jar into the house and kept it on the dining room table, so we could keep a careful eye on it. On April 21, 2017 while we ate breakfast, we checked the jar and saw a hole in the side of the cocoon.


We took the moth out on the porch that night, took some pictures of it in the twilight, then let it go. Perhaps its final ploy was to become a beautiful moth so that we would feel well rewarded for looking out for it for eight months, giving it a slightly better chance of finding a mate, getting some eggs laid, and perhaps projecting itself into the next generation.






Saturday, March 18, 2017

We have been remiss

We haven't done a blog for months. Partly it was because winter intervened, a down-time for most insects. Partly we have been busy. A publisher has shown some interest in our book of 100 common insects, but they wanted major revisions (mainly to make it a bit less conversational, and a bit more scientific), which we have now tried to do, and are waiting for their response. And an interesting job: we have been helping Game and Fish monitor a very rare bird which is spending the winter in Arkansas. We don't know if we are meant to say anything about it publicly, but we will give a full report after the species leaves the state this spring. Plus we have done a first draft of another book, Fifty Common Arkansas Spiders, which perhaps I will put a section of here shortly. And finally, we have been making regular trips to Tucson to see our grandson.

We are just now back from Tucson, so here is a report of things in the desert. When we were there in December it was surprisingly quiet in insect life (for us who naively thought everything went on all year there). On this new trip in early spring life seemed to be picking up. For instance, at our favorite Saguaro East National Park things were mostly quiet, but gorgeous fresh male Black Swallowtails had set up territories all along the trails.


Just as Falcate Orangetip butterflies come out early in the spring here in Arkansas, the Sara Orangetip comes out early in the desert, and they were fairly common in Arizona. We also saw, somewhat more special, the  "Pima" Desert Orangetip (we think).


There were other butterflies around, but not a lot, as the flowers were only just beginning to bloom. Also it seems that it is mainly male butterflies that emerge first in the spring, and they are so intent on finding females that they don't stop to nectar, which makes them very difficult to photograph.

One day we went out to Sweetwater, the city's water reprocessing plant, and it also was almost empty. In winter there are hundreds of wintering wildfowl, but now they had mostly left. I guess that's also a sign of spring. But there was at least one sign of spring right there at Sweetwater. The scruffy areas around the edges of the ponds were teeming with Round-tailed Ground Squirrels. The first one we saw aroused our sympathy, because it looked like it had a prolapsed uterus or some other disaster of childbirth. But when we looked more carefully, we saw we were actually looking at a male with a superabundance of testosterone.


A certain amount of excitement came when we visited the Tucson Botanical Garden. There were lots of butterflies flying around, especially Monarchs. And sure enough, there was a Monarch with a tag on its wing. There is a particular interest in the Monarchs of this southwestern state, as some of them winter along the Pacific Coast, and others in Southern Mexico, so it is hoped that returns on tags might straighten out some of the patterns. We took a picture of the tagged butterfly. (We have turned the picture upside-down so you can read the number on it.)


We sent our picture and reported the information to the address on the tag. After a few days we got a reply:

"Hi Norman, AK977 was tagged right here at the Tucson Botanical Gardens..."

Well, I guess that's information too.

Anyway, we weren't in Tucson to pursue science, we were there to visit our son and daughter-in-law, Gawain and Heather, and see how our grandson was progressing. In only three months he had changed a lot. He was more mobile, he was really strong, and he had an enormous smile for everyone. And the truth is, at this time of year there was more wildlife to be seen close at hand in their backyard and around their neighborhood than there was in the desert. The reason for this is in the style of gardens. They live "in town," which is to say more or less in the center of Tucson in an area of blocks of smallish houses with nice gardens. Now here in Jonesboro, most gardens consist of a lawn treated with heavy poisons from some lawn care company. One or two bushes on either side of the front door, one or two Bradford pear trees, and that's it, its own kind of barren desert (not the lush Sonoran desert of Tucson).  Because water is always an issue in a dry area, instead of poisoned lawns and pear trees in Tucson, the yards were planted more or less densely with cacti which are not only pretty to look at but draw in wildlife off the desert, particularly birds.

We spent a lot of time on their back porch around the bird feeders, and birds teemed. After our several visits we know some of the birds almost personally. There is a very tame mockingbird that deafens us when it sings near at hand, as it was doing constantly this trip. There is a very pretty vermilion flycatcher that has posts all around the house, and does little song flights. I have taken a hundred pictures of it, but it is hard to stop.


By the time we left neither the flycatcher nor the mockingbird had found a spouse yet, but they were working hard at it.

It is not just little dickey-birds that we see in their back yard. We have seen Kestrels and Peregrines, and the city of Tucson is overrun with Cooper's Hawks. We have not been on a trip without seeing several Cooper's, and at any moment one might shoot through the yard out of nowhere, scattering the birds in all directions.

  
 This trip we saw something especially good, and were so slow and rusty as birdwatchers (the insects have really stolen us away in the past ten or fifteen years) that we nearly missed it. Cheryl and I were taking the baby out in its pram for a morning walk around the six or eight blocks surrounding their house. We came around a corner, cars and people and houses on all sides, and there was a large hawk in the air over our heads. My guess is it was in migration and had spent the night in a tree there, and was just then trying to catch an early morning thermal and get on its way.

It was not very high, we had good light, we had our binoculars on it, and we were completely flummoxed.  We were looking straight up at it, and so we were seeing its underside. It was completely dark gray, with a narrow even darker gray border around its wings. The only distinctive marking was on the tail: The gray tail came out from the body, then about the middle there was a single white band that went all the way around the tail. Then it was gray again out to the end with a narrow band of white at the tip. We could not think of any hawk with these markings.

And then I did think of one, a bird I had seen at Big Bend forty years ago: A Common Black Hawk. But that was a wild guess. I couldn't actually think of a single field mark for that species, except that it was black. And I knew it was a very scarce bird (when we got back to the house and read up on them, there are only about 300 nesting pairs in the U.S.). Also, they are not found in cities, they are found in wild remote wetlands. So without better evidence than this unexpected sighting, we would have a hard time convincing ourselves that this is what we were seeing.

The bird had found its thermal and was now rapidly spiraling upward, and would soon be gone. I was carrying my close-up camera for insects. It had a 100 mm macro (for extreme close-ups) lens, my telephoto lens, regretfully, back at the house. Suddenly it occurred to me that the camera I had (100mm) was like a weak telephoto, better than nothing. The hawk was still pretty close. I changed the setting to use it for a distant shot, pointed it upward (the hawk was spiraling up higher and higher), I pressed the button, and nothing happened. I looked at the camera and realized I had forgotten to turn it on. I quickly turned it on, focused on the bird again (so high up by now it was nearly out of sight), and took one despairing shot before it disappeared. Here is the picture.


It doesn't look like it would be very helpful, but here is where you see the marvels of modern digital cameras. I downloaded it onto my computer and then magnified it as much as I possibly could, and then adjusted it to bring out as much contrast as possible. And here is the image I ended up with:


There is the single white band through the center of the tail. When we got the books out, we found that was indeed a mark on the Common Black Hawk, and there is only one other hawk with that marking, the Harris's Hawk. That would be a problem in our ID. Harris's Hawks are evidently common in Tucson, the city itself, and the Common Black Hawk would only be a great rarity in migration. So we scrutinized the two species side by side in the books. Harris's Hawk has panels of bright rufous on its wings, both above and below, and we had seen this bird in bright morning sunlight, and there was no trace of color, only the different shades of dark gray. And you can see in the picture here that the wings have a narrow border of black outlining them, something we had seen clearly and commented on, and a marking shown in the books for the Common Black Hawk, but with no such marking in the Harris's. And then we found a clincher, a mark we hadn't known about, and had not noticed when we were looking at the bird. The Common Black Hawk has what the books describe as a "comma" of white out near the tip of the wings. In the picture here, with the contrast turned way up, the white "comma" was perfectly clear (making allowance for the poorness of the picture).


Gawain looked up the Audubon site on his phone and a Common Black Hawk had been seen north-west of Tucson within the last couple of days.

Thursday, October 27, 2016

Bumble Bees in our yard in Jonesboro, summer 2016

For a long time we have wanted to get interested in studying bees, but they are notoriously difficult to identify and there must be some 3000 species in the United States. But we decided if we started with one small, relatively easy to identify group, it might be a way in, and our friend Herschel Raney suggested we look at bumble bees this year, and they seemed perfect. So in 2016 we became seriously interested in the bumble bees that visited our garden. (We knew nothing at all about them.) We had a guide to identification (Bumble Bees of North America, Thorp et al.,[2014]), and as our first step we checked their distribution maps to see what species were possible in our area. Here is the list we came up with:

Bombus bimaculatus, the Two-spotted Bumble Bee
B. griseocollis, the Brown-belted Bumble Bee
B. vagans, the Half-black Bumble Bee
B. auricomus, the Black and Gold Bumble Bee
B. pensylvanicus, the American Bumble Bee
B. fraternus, the Southern Plains Bumble Bee
B. impatiens, the Common Eastern Bumble Bee
("pensylvanicus," by the way, is the correct spelling. It's just something that happens when you latinize a word.)

We had beds of flowers designed, over the years, in such a way that when one group of flowers finished blooming, another flower series would take over,  so that we had almost continuously blooming flowers. This was designed to attract butterflies, but it now also turned out to attract a continuously changing suite of bumble bees. By the time the first bumble bees showed up in early June, the pink phlox flowers were up, terrific for long-tongued moths and butterflies, but with their single deep narrow holes to the nectaries, they did not attract a single bumble bee. However, the pink coneflowers with their daisy-like flowers, each flower with an abundance of florets, and, in our pond, pickerelweed, with spikes of purple flowers, so that in each case a bumble bee could visit several nectaries by crawling around, without having to take off with its heavy body and land again, were both very attractive to bumble bees. At first we had mainly Bombus bimaculatus, Two-spotted Bumble Bees. I assumed the two black squares on the sides of the second abdominal segment were the source of the name, and these made the species easy to identify. ( I have recently read it is because of the two yellow spots, so now I’m not quite sure where I am.) Anyway, here is the Two-spotted Bumble Bee.



Most bumble bees are more or less alike, except with different patterns of black and yellow. So let's take this picture to orient ourselves, and see marks we need to see to identify the different species. Starting from the front, we see that this one has yellow at the top of the head. Some species have yellow at the top of the head, some have black. Next, we see that the thorax is completely yellow. Some species have a band of black over the top of the thorax, or black on the sides of the thorax. Different species have different segments of the abdomen black or yellow. On this species the belly is black, but the upper half of the first abdominal segment is yellow, and the second abdominal segment is yellow in the middle, but black along the sides, and then the remaining five segments (seven segments altogether) are black. Here it is now from the back:




The black spot is frequent in the center of the thorax on top. It is usually a sort of bald spot.


This was the first of the seven species we might see, and at first it was the only bumble bee around. It was particularly common on the dense bed of flowering pickerelweed in our pond. But occasionally we would see a Brown-belted Bumble Bee in the pink coneflowers out in the front yard.



This species similarly had yellow on top of the head and an all yellow thorax, and the first abdominal segment yellow. But the second segment was brown or at least brownish.

 And also occasionally we saw the Half-black Bumble Bee.


And once more, in this third of seven possible species, the top of the head was yellow, and the thorax was completely yellow. But in this case, the first two segments of the abdomen were more or less yellow, and the following segments were black, though with lengthy yellow fringes.




But with individuals with more modest fringes, it was easier to see why the species was called the Half-black Bumble Bee.




Then there was a change. The Two-spotted Bumble Bee became increasingly scarce, while a new species appeared. This one was very natty and quite different from the others. The front half of the thorax was yellow, the back half black, a broad black band pulled over the top. Two or three segments of the abdomen were yellow, then the last four formed a solidly black end.


This fit the pattern of B. auricomus, the Black and Gold Bumble Bee, and so that was what we called it, the fourth of our seven possibles.

Now the basket flowers were blooming out in the front yard, and we got a new species.



On this one, the back half of the thorax was black, the sides of the thorax were black, and all the segments of the abdomen were yellow, except the very last, which was dingy. Now we had a problem, because two species seemed to have that pattern, B. pensylvanicus, the American Bumble Bee, which was common everywhere, and B. fervidus, the Yellow Bumble Bee, which was common almost everywhere, though the range map did not quite touch our region. We went back and forth on this for quite a while until we remembered that other field mark. B. fervidus had yellow sides to the thorax, while pensylvanicus had black, and on ours we could see the black clearly. So pensylvanicus was the fifth of our seven possibles.

But then we found another problem. In the cup plants, also very popular with bumble bees, which were taking over from the fading basket flowers, we began seeing bumble bees marked like this:



This was the pattern of auricomus, the Black and Gold Bumble Bee, but something was not quite right. When we checked carefully through the descriptions of the various bumble bees, we discovered that pensylvanicus had an alternate pattern that looked exactly like this. This was confirmed for us when we were lucky enough to see a male pensylvanicus in the typical pattern mating with a female (a queen, that is to say) in this new pattern.



So these were pensylvanicus in a new pattern. But what about those first ones we saw? Were they Black and Gold? Alas, we remembered another field mark we needed to look at. The Black and Gold Bumble Bee has yellow on the top of the head; pensylvanicus has black, and that meant black in both of its color patterns. We checked all our photographs, and where the top of the head was at all visible, they were all black. We eliminated Black and Gold from our list, and now we were back to four of our seven possibles.

We felt much better however when, for one day only, we had a visit from a very handsome new species, Bombus fraternus, the Southern Plains Bumble Bee.



This one, in very clean black and pale yellow, had the first two segments of the abdomen pale, the rest black, and had a very slim black band over the back of the thorax just between the wings. So we now had five of the seven possible. We decided we weren't going to get Black and Gold, but we thought we were still likely to get the last one, B. impatiens, the Common Eastern Bumble Bee. We waited day after day for it to show up. The season was moving towards fall, however, and all of our seasonal flowers were coming to an end, and it didn't seem like any were left to come to serve as an attractant. Our scraggy weedy goldenrod plants, off in an untended corner of our yard, had not come out yet, but they didn't seem like they would draw in any bumble bees when they did.

That was the situation when we left to go to Arizona to see our brand new grandson.

Three weeks later we returned to find the goldenrod in full bloom and crawling with Bombus impatiens for a nice finish to the year, six out of the possible seven, not too bad for one garden.





B. impatiens (the name comes from the Latin name of a flower it particularly favors, jewelweed, though evidently goldenrod will work in a pinch) has yellow on top of the head, yellow thorax (with a particularly large bald spot), first segment of the abdomen yellow and the rest black.

I read now that the favorite habitat of B. auricomus, the Black and Gold, is not the garden, but open fields and farmland. That's where we will be looking for it next spring.







Wednesday, September 28, 2016

Paying attention to detail

We went out to our son's house in Tucson to see our brand new (and first) grandson.  I know this is mainly an insect blog, but I hope I can be excused this single mammal photograph.



Actually, I'm going to go on and discuss another vertebrate animal, a bird.

Cheryl was there to help out with the new baby, and my job was, essentially, to stay out of everyone's way. It was still summer and their bird feeders had not been in operation, but it was late summer with birds beginning to move around, so I started things up by filling a finch feeder with niger seed.

I spent a lot of time out on the back porch watching the insect, spider, lizard activity, and, when they arrived (almost immediately), the birds at the feeder. This was one of those diabolical feeders that would only offer food to desirable Lesser Goldfinches, leaving the over-abundant House Finches out in the cold (not a good metaphor when the temperature is in the 90's).


The way it works is, instead of the holes being above the perches, the holes are below them, and they can only be accessed by hanging upside down, which in theory only the goldfinches can deal with. It more or less worked, though there was a male House Finch who mastered it, and came regularly.


Where we live in Jonesboro, NE Arkansas, we have American Goldfinches, a related but different species. The Lesser Goldfinch is a western bird we only see when we come to Tucson, so we are not overly familiar with it. I remembered reading at some point that the Lesser comes with its back in two color forms, though I couldn't remember what the two colors were, or how the two species were distributed.  So I got out my Sibley and read "adult males in southern Texas are black-backed; frequency of green-backed adult males increases north and west to near 100% west of New Mexico." We were west of New Mexico, so 99% of the adult males here should be green-backed.

The theme of this blog is paying attention to details and here was a detail I had paid no attention to and I had never even noticed the back color of these birds. So I looked, and sure enough, the males were all green-backed.


And then virtually the next bird I saw was black-backed.


And what a beautiful bird it was, and if I hadn't been paying attention to details I would have missed it entirely, and so I would have missed this lovely 1% rarity (though it occurs to me I must have not paid attention to them by the million in South Texas, where we often go, and where they are common).



Here's another example of learning new things by paying attention to detail. In our backyard in Jonesboro there is a sugarberry tree, which is closely related to hackberry trees. In fact, Hackberry Butterflies lay their eggs on it, just as they do on regular hackberries, and we raise Hackberry Emperors by the score, a pretty orange and black butterfly. In our son's backyard there is, similarly, a hackberry tree, and it is covered with identical looking caterpillars, and eggs laid by an orange and black butterfly which is virtually identical, the Princess Leilia. When we are in Arkansas, in the east, we know we are seeing a Hackberry Butterfly, and when we are in the desert southwest, we are seeing Princess Leilia.

So here is Princess Leilia laying eggs in the hackberry tree in my son's backyard in Tucson.


As I was taking this picture, a revelation came to me. This butterfly is one of a group of butterflies called Emperors, the Hackberry Emperor, the Tawny Emperor, a few others, and here, because a butterfly with a feminine name can't be an emperor, its name is Empress Leilia, and always before this I had mistakenly called it Princess Leilia (probably confusing it with the heroine in
Star Wars). Unfortunately I still automatically call it by the wrong name, but this was only the first of my errors of poor attention to details.

I opened my book, Butterflies of Arizona, A Photographic Guide (2001) to p. 208-9, and learned that the Hackberry Emperor and Empress Leilia occurred side by side (in other words, the Hackberry was not strictly eastern), and the details had to be studied very carefully to tell which was which. A first tip was, Empress Leilia laid its eggs in Desert Hackberry, and Hackberry Emperor laid its eggs in Netleaf Hackberry trees. I asked our son's wife (a tree expert) what kind they had, and she said it was a Netleaf, and I learned to my surprise that what we had in their yard were Hackberry Emperors, just like ours back home. So how do you tell them apart?

Let's take another look at the Hackberry.


If you look just to the left of the head (or just to the right of the head), along the front of the wing, there is a pale orange panel with two small dark spots on it, then, towards us a little way, a longer thin curved spot, a little bit like a smiley face. Those three spots make this a Hackberry Emperor. This is the one in our son's backyard. Note the egg-stuffed abdomen.

Then when we went out in the desert, in the vicinity of a Desert Hackberry tree we saw this one:




Now instead of having three little spots along the leading edge of the wings it has two bigger spots, with a pale creamy area between them. This is Empress Leilia. Here are the two close up.







Let me give just one more kind of interesting example of paying attention to details, and this creature is so tiny, 2-3 mm, you can barely see it at all, let alone its fine details. But the marvel of digital cameras helps out, to blow the picture up to visibility. In this case we are looking at mosquitoes in the genus Aedes, the genus that is so much in the news lately. Here is the one we have at home in Arkansas



It is Aedes albopictus, the Asian Tiger Mosquito. It's a very tiny mosquito, about half the size of most mosquitoes, looking like not much more than a black dot on your skin. It is quite handsome with its black and white leg bands and the white spots on its abdomen. It tends to bite during the day (morning and late afternoon). Besides being annoying, this one, in the tropics, carries dengue fever, which fortunately is very rare here. Here is the detail: Note, easier to see on the second view, a broken white dash going across the back of the thorax. Then, in front, a white stripe going down the center of the thorax.

When we got to Tucson, we found a different Aedes.



It is the same in all respects, except it doesn't have the white stripe down the center of the thorax. This is the notorious Aedes aegypti, the transmitter of the Zika virus. The mosquito seems to be established across the southern border of the country from Florida to California. So far, except for a couple of spots in Miami, there is no Zika virus around for it to carry, but naturally it is being closely watched.



Sunday, August 7, 2016

100 Common Insects of Arkansas and the MidSouth (continued)

As you can see by the new title for our insect book, it has gotten longer and covers a larger area. We kept seeing creatures we wanted to add. It's probably over a hundred now. Cheryl is helping me clean up syntax, and especially, when I hit something I don't know, making sure I do some research instead of, as I usually do, making up an answer. As Huck said, it's mainly true with a few stretchers.







Wheel Bug, Arilus Cristatus


This insect is in the order Hemiptera, or "the true bugs." Colloquially, all insects are called "bugs," but technically, the true bugs are only those in this order, and are marked by having the basal half of the forewings leathery and the outer half membranous, a segmented beak that folds under the chin when not in use, and they do not have complete metamorphosis, hatching out of the egg more or less like a small version of the adult. Some use their beaks to suck plant juices, some to suck the juices of their prey. The Wheel Bug is one of the latter.

If you have a garden (that you don't pour a lot of poisons into), you will be sure to have seen this big (over an inch long) bug with what looks like a half saw-blade on the back of its thorax. The long beak looks formidable and it really is. If you try to pick it up and it gives you a jab it will make you yell. They use it to kill their prey (chiefly caterpillars) and turn the insides into soup which they suck dry. I don't mean you should be stamping on them, I mean you should be admiring them as powerful actors in the natural system around you which needs a balance between survivors and population controllers.








Eight-spotted Forester, Alypia octomaculata


Here is a very handsome and commonly seen day-flying moth. Most moths are secretive, but this one WANTS to be seen. Black white and red is a color-scheme well known throughout nature, to birds, lizards, insects, spiders, even human beings (think of bees and wasps: we see black and orange or black and yellow bands, and we know not to touch). These are warning colors; it's technically called aposematic coloration. Some combination of black and white and orange-red means "Don't touch me, I have a nasty bite, or an envenomed sting, or I taste terrible to the point of being poisonous." Sometimes they are just pretending with their colors, and can't hurt you or don't taste bad, but who wants to take the chance?








Bald-faced Hornet, Dolichovespula maculata



These make the basketball-sized paper nests hidden in bushy foliage (only coming into view when leaves are lost in autumn). I remember finding a nest in mid-winter (the inhabitants presumably dead and gone) and bringing it home and setting it attractively in a corner of my study, only to learn, when the room had warmed up to spring-like temperature, that a couple of dozen pregnant queens waiting for next year were overwintering in the nest and were now all emerging early and in very bad tempers.

These hornets are meat-eaters and the workers go out and catch horse flies or butterflies or whatever insects they can and tear them up in pieces and bring them back to the nest. They have a special trick. On cold mornings they can, by shivering, warm themselves up to mammal-like temperatures. They then go out and look for insects that are too cold to fly away. You can see them flying along and smashing into every black spot they see on a leaf, in case it is a tasty insect.

(I didn't realize until I put that picture up how much it looked like a gorilla wrapped to be a mummy,)








Paper Wasp, Polistes metricus


There are several species of Polistes paper wasps. You might see them early in spring scraping fiber off smooth wood or plant stocks, which they mix with their saliva and make into a heavy gray paper, called carton. With it they make the pizza-shaped open nests that are hung from foliage, or often under the eaves of your house. There is a large all red species (P. carolinus) which I prevent from nesting around our house, since they tend to attack us, but the others (with various patterns of black, yellow, and red) are inoffensive and we enjoy watching them develop. The nest here is in an early stage. The over-wintered pregnant queen started this nest by herself and raised the first few workers. This is the perilous time and many nests fail, but she has made it through. Up near the top of the picture you can see eggs inside the cells, and a newly hatched grub. Below, a fully developed grub is spinning a cocoon around itself. Then there are three closed cocoons developing. The dark smudge at the top of the nest is the queen herself, resting on the stem that supports the nest. She no longer has to risk her life going out and foraging. Her job now is to stay there laying eggs while the others bring caterpillars and other insects to feed the babies like birds in a nest. There may be fifty or so workers by the end of the season.








Paper Wasp, continued, Polistes exclamans




Here is a mature nest in September. It looks to me like the flight deck of an aircraft carrier, ready for combat. When I got under the nest, which is in the eaves of the house, they all snapped to attention, and if you look you can see almost every one is staring straight at me. This is a peaceful species, but I didn't go any closer.








Paper Wasps, Polistes spp. (continued)



At the end of the season the queen and all the workers will die, but before they do they begin producing males and virgin queens. As it starts getting colder the virgin queens begin looking for sheltered places to hibernate in, hollow logs or, particularly, insides of buildings, attics or openings in the eaves. As they find these places, it turns out the males (identifiable by their white faces) are already waiting to waylay them and won't let them in till they have mated. The males then die, and the pregnant queens winter in the shelters, then emerge the following spring to start a new generation.