Banded Tussock Moth caterpillar (click photos to enlarge)
I usually think of the end of “caterpillar season” as being a week or two after the Museum’s annual BugFest event in September. This year (and maybe its just because I am retired and out and about more) I have been seeing the larvae of quite a few species in my travels well into October including Imperial Moths, Luna Moths, and the ubiquitous Woolly Bears. But around the house, there is one species that is dominant late in this season, the Banded Tussock Moth, Halysidota tessellaris.
Banded Tussock Moth larva on oak leaf
Full-grown caterpillars are about 1.5 inches long. Each body segment is densely covered with tubercles bearing tufts of short or long hairs (lashes) that are whitish, yellow-brown, silver-gray or black. From the second thoracic segment there is a pair of long black lashes and shorter white lashes that point forward, and from the third thoracic segment is a pair of black and white lashes that usually point away from the body at right angles. At the rear of the body, two black lashes point backward.
Banded Tussock Moth larva raising its body in search of a new perch
I am always struck by the tufts of “hairs” on certain caterpillars. They remind me of various things with texture – brushes (some are even like toothbrushes), some sort of elongate fancy breed of show dog, or a teenager with a wild hairdo.
Banded Tussock Moth larva crawling on white background
The true tussock moths, like the common White-marked Tussock Moth caterpillar, are members of a different family of moths, the Lymantriidae. The Banded Tussock Moth is a member of the Arctiidae, which includes the Tiger Moths.
Banded Tussock Moth caterpillar in a stare-down
This species is easily observed as it sits out in the open on leaves of its many host plants (oak, hickory, ash, and many other shrubs and trees) or in its travels to a pupation site. I am finding them now on my deck rail, the screen porch, the trash can lid, and just sitting or crawling on the ground. This boldness may indicate that they are distasteful or just too bristly for many birds. And one reference indicates that, like many members of the true tussock moth caterpillar group, the Banded Tussock may cause skin irritation in sensitive individuals. Guess I truly am an insensitive guy, as I have handled them with no ill effects.
I looked out the window this morning and saw that the dawn had left its mark on the meadow – faint traces of ice coated the grasses and other low-lying vegetation under the power line – the season’s first frost.
Grass blade with ice crystals
Frost is deposition of water vapor directly into ice crystals on a cold surface. Frost typically forms on objects close to the ground, such as blades of grass. At night, a blade of grass loses energy by emitting radiation, but it absorbs energy emitted by surrounding objects. Under clear nighttime skies like we had last night, objects near the ground emit more radiation than they receive from the sky, and so a blade of grass cools due to the net energy loss. When temperatures hover near the freezing point and an object such as a blade of grass gets cold enough, frost will form on it.
Mourning Dove feather
Up on the hill above the garden, the frost had formed only on very low-lying objects – mainly the grass that I had recently mowed or objects lying on the grass such as a few feathers near the bird feeder station.
Sweet Gum leaf
As I walked downhill the frost had reached higher and by the time I reached the low point of the power line meadow, it had touched vegetation up to 2 feet off the ground (tree saplings, tall grasses, etc.) probably due to the sinking and collecting of cold, humid air in these low pockets overnight.
Frost Aster flowers
Even the aptly-named Frost Aster flowers had a coating of crystals at the base of the hill, but not up near the garden. As the sun rose higher, the icy filigree began its retreat until it finally lingered in only the deepest shade in the valley, and even there, it would soon succumb and have to wait for another dawn to be reborn. I welcome the first frost as a sign of good things to come – campfires under a starry sky, the simple pleasure of heating with wood that you cut and split yourself, and the return of migrants from the far north. It is just the beginning, but the cold, crisp nights of winter are not far behind, and with them, a new set of adventures. On the next chilly morning, go outside and look at the handiwork of frost and you will be amazed at her delicate attention to detail as she paints the landscape.
I had an outing this weekend with a great group of folks in Cataloochee Valley and up on the Blue Ridge Parkway. Our goals were to observe the elk during the mating season ritual called the rut and experience the beauty of the mountains during the fall leaf season. I’d say mission accomplished on both. It was overcast and cool on Saturday morning as we drove into the valley. We were greeted at the entrance by one lone bull elk and a little farther down the road a large crowd of visitors at the first elk herd.
Bull Elk in Cataloochee Valley
One large bull was busy herding his harem of cows and occasionally chasing off a small spike bull that was feeding some distance from the herd of cows (but apparently not far enough away for the big bull). Early morning is one of the best times to see the elk as they tend to be feeding and, during the rut in September and October, interacting with one another.
Bull Elk bugling
Each year at this time males in their prime (usually 5 to 8 years of age) gather small herds of cows and calves and aggressively defend them from other bulls. This is done by a series of displays: bugling, a hauntingly beautiful and surprisingly high-pitched call; thrashing bushes and other vegetation with their antlers; and occasionally engaging in sparring matches with other large bulls by locking antlers and shoving in a show of strength.
Bull Elk courting a collared cow
When the cows come into estrus, the mating begins. A cow is receptive for mating less than 24 hours. She won’t be willing to mate again until her second estrus cycle arrives in 20 days so bulls are constantly checking on the cows in their herd. Bulls can be quite aggressive toward cows as they herd them, but then during courtship their behavior is decidedly more gentle. He may approach her and lick her to check her receptiveness and, if she is ready and willing, mount her to mate. This day had no actual mating or fights with other males, but the bull stayed busy, bugled often, and looked exhausted at times (bulls may lose 20% of their weight during the rut).
Palmer Church
The rest of the day we explored the woods and stream sides and walked around some of the many historic structures in the valley. Several houses and barns, a one room school, cemeteries and a church are all that remain of a once thriving community that had to leave when the land became part of Great Smoky Mountains National Park in 1934. There are auto tour brochures available for a nominal fee at the information kiosk near the valley entrance that give a detailed history of the valley and some of its notable inhabitants.
Bull Elk with fall color
Late in the day we found ourselves (along with hundreds of other visitors in often car-clogged roads) watching the elk as they returned to the fields after being in the shade of the forest much of the day.
Early morning mist along Blue Ridge Parkway
The next morning most of the group wanted to head up onto the Blue Ridge Parkway for some fall color so we headed out and started heading north from Balsam Gap. The cool night and humid atmosphere had created ideal conditions for mist and low hanging clouds, a photographers dream for this time of year on the Parkway.
Ocean of clouds in valley below Blue Ridge Parkway
At first, we saw only patches of mist hugging some ridges. As we climbed in elevation and the road shifted to the other side of the mountains, an ocean of clouds spread out above the valley floor with isolated peaks popping through the gray sea. This type of scene has given rise to the name, Islands in the Sky, for these mountaintops protruding above the misty sea of clouds. It also refers to the unique ecological communities that are adapted to the cold conditions atop our highest mountains.
Panorama from Richland Balsam
As we continued north, the warmth of the sun caused the sea of clouds to recede leaving us with an unobstructed view of row upon row of ridges speckled with fall colors.
Lower part of Yellowstone Falls
Our final stop was a short hike down to Yellowstone Falls, one of the more popular hikes along this section of the Parkway. After winding through a thicket of Rhododendron and Mountain Laurel, you come out on a beautiful series of waterfalls. The hike is well worth the steep climb back out. And here’s something to consider next time you visit a popular waterfall. If you are at the top of the falls and look down and see a group of people with cameras looking up at you, try not to stay too long out in the open…they may be waiting for a chance to get a photo or two of the scene without people in the picture. As we parted ways, I think we all were appreciative of the sights and sounds we had experienced on this magnificent fall weekend. I look forward to the cooler weather and changing landscape and wildlife that the new season will bring.
Here are a few more photos from the trip.
Boards of historic barn in Cataloochee ValleyYoung bull Elk with velvet on antlersRough sawn board on Palmer barnMountain Ash berriesSassafras leavesRed Spruce against ocean of clouds
Stone Mountain State Park (click photos to enlarge)
The past several days II have been on the road in the mountains of North Carolina. I had a program on Saturday at Stone Mountain State Park and had a great hike across the large granite dome for which the park is named. The park was packed with campers and hikers taking advantage of the start of fall colors and perhaps visiting an open state park instead of the many federal lands closed by the unfortunate government shutdown.
Crowders Mountain State Park
After a rainy couple of days along the Blue Ridge Parkway (the road is still open but facilities are closed) I visited Crowders Mountain State Park near Gastonia. The weather cleared and the two mile hike to the summit of The Pinnacle was a welcome sunny stroll.
Chestnut Oak forest
The main trail passes through a forest dominated by Chestnut Oak, Virginia Pine, and Sourwood, with an open understory of Sparkleberry, Sassafras, Dogwood, and various herbaceous species adapted to the dry rocky slopes.
Phengodid Beetle female or immature
There was a lot of frass (caterpillar poop) on the trail and a couple of the frass-makers were spotted along the way, including a huge Imperial Moth larvae and a Luna Moth caterpillar on Sourwood (yes, I really do look for such things while hiking). But one thing on the trail really stood out – an unusual larviform creature about 2 inches long. I recognized it as an amazing beetle I had once found on a night walk at another state park in the Sandhills. On that night, I saw a bright glow on the trail and stooped to pick it up. It looked like a worm or caterpillar with a series of bright glowing dots on each side. It was so bright I could read my watch by it. I have since found several of these so-called Glowworms (not to be confused with some Lightning Bug larvae which are also known as Glowworms). This one is the larva or adult female of a Glowworm Beetle, probably in the genus Phengodes. The females and larvae are bioluminescent. The pattern of glowing dots is said to resemble a train car illuminated from inside at night and has given this unusual insect another common name – Railroad Worm. Adult females are wingless and almost indistinguishable from the larvae. Both are predaceous on millipedes, which they resemble in color and shape. Adult males have wings, probably do not feed, are active primarily at night, and are adorned with intricate antennae. See http://bugguide.net/node/view/9382/bgimage?from=0 for more photos of these bizarre insects.
The mountains are calling and I must go.
John Muir
For my birthday a couple of weeks ago, I decided to revisit one of the most beautiful places I have been in the East, Dolly Sods Wilderness in West Virginia. Many years ago I had read about this unique highlands area and had wanted to visit ever since. Last year I finally made it and it was worth the wait.
Dolly Sods is a 17,000+ acre wilderness in the Monongahela National Forest in West Virginia. It is an unusual environment in that it contains bog and heath bald habitats which are much more typical of southern Canada.
Dominant trees include Red Spruce, Sugar Maple, and Quaking Aspen. On some trails I feel like I am walking in Yellowstone, Alaska, or Canada.
There are miles of well marked and easy to hike trails. They take you through a variety of habitats as you pass from open bald into forest. To me, one of the more amazing things about this beautiful place is the abundance of ferns. Hay-scented and Bracken Ferns seem to dominate, and they occur in huge patches in the balds and the forest understory.
Fall color was at its peak when I was there, and the highlands of Dolly Sods are absolutely incredible with a variety of colors from blazing red to bright yellow both on the ground and in the trees. Last year I was there a week later and had to leave a day early because it started snowing. This area is known for harsh weather conditions, so visitors need to be aware of changing conditions and come prepared.
The area is rich in fruiting shrubs and groundcover including many species of blueberries, huckleberries, and cranberries. The tart cranberries made a delicious addition to breakfast oatmeal.
The area reportedly has some unusual wildlife such as Fisher and Snowshoe Hare, again, much more like northern forests than other areas of the Appalachian Mountains. I did see some evidence of Black Bears this time and heard the howls of Coyotes and hoots of Barred Owls late at night.
Throughout the trail system there are a number of well established campsites. The area is pretty heavily used so I recommend camping in these locations so as not to create more disturbance to this unique environment. Since I was backpacking I did not carry my usual assortment of camera gear but relied on my phones’ camera instead. I leave you with a few images of this beautiful area that I will surely visit again.
The abundance of insects feeding on pollen and nectar in the goldenrod patch out on the power line has naturally attracted an array of predators.
Wheel Bug (click on photos to enlarge)
One of the more formidable-looking of these is the Wheel Bug, Arilus cristatus, our largest member of the so-called Assassin Bug group. Wheel Bugs are named for the unusual gear-like projection on the dorsal surface of the thorax of the adult insects. They are efficient predators of many types of insects including caterpillars, beetles, and bees. Wheel Bugs move slowly through vegetation like goldenrod searching for prey which they grab with their long front legs and then pierce with their stout beak. Their saliva contains a toxin that immobilizes and kills its victims within a minute or less. They then drain the body fluids from the victim. That same beak can inflict a painful bite on a human if you accidentally grab a Wheel Bug, but, left to their own, they will not bother us. In fact, Wheel Bugs are considered beneficial garden insects as they prey on a number of bugs we consider pests.
Wheel Bug and Honeybee prey
I encountered a couple of these impressive insects while walking through the goldenrod last week. One was hunting on some flowers, the other had successfully captured a Honeybee. I grabbed a few quick photos and moved on. When I looked at the images later I noticed something I had missed in the field.
Wheel Bug with bee with Freeloader Fly
There was a tiny fly on the bee near the point where the Wheel Bug was feeding. I recognized it as one of an interesting group of flies known as Freeloader Flies. These tiny marauders are kleptoparasites and steal a meal from the jaws of predators such as Assassin Bugs and various spiders. I had seen them once before in the garden when I photographed a Black and Yellow Argiope Spider feeding on a Stink Bug.
Black and Yellow Argiope with prey
On that day, I once again did not see the tiny flies until I had taken a few images. At that time I had no idea what these miniature thieves were and was not even sure what they were doing other than living dangerously. A web search helped me discover the amazing world of kleptoparasitic flies.
Freeloader Fly stealing a meal at the jaws of an Argiope Spider
Other names for this interesting group of insects include Jackal Flies and Filth Flies (their larvae feed on decaying organic matter and some species may develop in manure). They apparently are attracted to their meal by chemical odors released by the victims. And it is unclear whether they are merely licking spilled fluids from the victim or whether they may actually penetrate the cuticle of the prey and ingest tissues that the predator has liquified by its injections into the dead prey. The adults of some species of Freeloader Flies have been observed to follow a particular predator in order to partake of its meals. I guess in this case, it is a different sort of meals on wheels:)
I love nature, I just don’t want to get any of it on me.
Woody Allen
I gave a talk the other night to the Raleigh Chapter of the Carolina’s Nature Photographers Association. They were a great group and seemed to enjoy my topic about macro photography. One story, in particular, raised a few eyebrows. It was about something I see going on right now out in the patch of goldenrod under the power line.
Soldier Beetle feeding on Goldenrod (click photos to enlarge)
The patch is abuzz with all sorts of insects feeding on the copious quantities of nectar and pollen to be found in the golden buffet. Among the many foragers are a group of common beetles known as Soldier Beetles (also known as Leatherwings), Chauliognathussp. They are busy feeding on pollen and mating and are frequent visitors to various species of goldenrod and boneset that occur on the power line. In the past couple of weeks I have noticed something strange happening amongst their ranks…
Dead Soldier Beetle on goldenrod
The beetles are hanging down underneath the flowers with their wings askew in what looks like some strange circus acrobat position, but with a decidedly non-circus look about them. They look and are, in fact, dead.
Soldier Beetle on boneset
And there are lots of them this year – a large die-off of these beetles in what is certainly one of nature’s more bizarre local stories.
Group of dead Soldier Beetles
A close look at the dead bug shows a fuzzy white coating coming out between the segments of the lifeless body. The culprit is one of a group of arthropod pathogenic fungi. There are apparently many species of these insidious fungi, and many are host specific. The general life cycle is that an insect picks up a spore of the fungus on its exoskeleton while moving about in its environment. The spore then germinates and penetrates into the exoskeleton of its host via mechanical pressure and the production of enzymes which help dissolve an entry hole. Once inside, the fungus grows and divides. There is often an attack on the nervous system of the host which causes a change in its behavior near the time of death. In the case of these Soldier Beetles, they clamp onto the vegetation with their mandibles. In one study in Arkansas, an estimated 20% of the beetles surveyed in a field were infected by the fungus. And in an interesting finding, the researchers observed “by an unknown mechanism the fungus causes the dead beetles to raise their elytra between 2400 and 0700 hours during the night”. The position of the raised wings presumably provides a more efficient means for the fungus to disperse its spores from the dead insect.
I have been away a few days celebrating a major birthday (hard to believe it is that number) and returned to find a few caterpillars from BugFest still active (most were released the day after the event). I was particularly pleased to see the snappily-attired Turbulent Phosphila munching away on its host plant, Greenbrier (Smilax sp.). I remember the first time I found one of these pin-striped beauties I could not decide which end was which, a common caterpillar conundrum. A frequent defense strategy of many types of insects is to present a false head to would-be predators. This usually involves eye spots of some sort since we, and most vertebrate predators like birds, associate eyes with the head of an animal. By going after the head first, a bird is likely to immobilize its prey quickly and cut off any escape attempt.
Turbulent Phosphila – which end is which?
A close look reveals the truth – the last three segments of the rear of the caterpillar are somewhat enlarged and have prominent white spots suggesting eyes. Ironically, the true head end of the larva also has false eye spots on the thorax. The true eyes, like those of most caterpillars, are diminutive and arranged in arcs on the side of the caterpillar’s true head capsule, which is tucked on the right side of the larva in the image above (note the presence of the short antennae and true legs on that end). Maybe it is no accident that referee shirts look like the bold patterns of this larva – many of us question where their eyes are as well.
Turbulent Phosphila on Smilax sp.
David Wagner (Owlet Caterpillars of Eastern North America) states that “the bold coloration is suggestive that the insect is chemically protected, although it remains to be shown if the Turbulent Phosphila is in fact unpalatable, or if its patterning is largely a ruse”.
Grouping of Turbulent Phosphila larvae
Young caterpillars are gregarious feeders on various species of Greenbrier, but as they grow older, they become more solitary. Finding a group of them on the underside of a Greenbrier leaf or clumped on a vine is a caterpillar-lover’s (and perhaps graphic artist’s) delight. The moth has two generations per year throughout much of our region and can often be found as late as November in the coastal plain. Finding the Curve-lined Owlet caterpillar, and now these interesting larvae, on Greenbrier, gives me a reason to appreciate this often maligned vine.
While out searching for caterpillars last week I came across a tiny juvenile Gray Treefrog in the bushes alongside the road. I walked back to the car to get my camera but when I returned, the frog had disappeared. As I looked for it I caught a movement out of the corner of my eye. A closer look revealed a tale of tragedy and beauty. I recognized the victim as a Golden Tortoise Beetle, a beautiful insect I have seen in the garden several times. But I wasn’t sure who the colorful predator was other than some sort of stinkbug. As I watched, it moved around to the underside of the leaf where its colors stood out more against the lighter background.
The long proboscis of a Florida Predatory Stinkbug with prey
The batteries in my flash were almost dead so I took just three pictures before giving up as the rain moved in. This critter was indeed strange as it walked around the leaf balancing its prize at the end of an incredibly long beak. A web search showed the vivid predator to be a Florida Predatory Stinkbug, Euthyrhynchus floridanus. When they jab their prey with their proboscis, they inject a toxin that slowly immobilizes the prey.
Florida Predatory Stinkbug
I was watching it move around with its prey when I noticed several more stinkbugs clustered in a folded leaf nearby. Juveniles (and, less often, adults) often aggregate, and are known to attack larger prey as a group. This aggregation behavior apparently allows them to successfully attack prey too large to be subdued by a single stinkbug, much like why wolves hunt in a pack. Imagine packs of tiny, brightly-colored wolf insects with jointed swords on their noses stalking prey in your backyard! I am constantly amazed by the complex life cycles and beauty to be found in nature.
“The caterpillar does all the work but the butterfly gets all the publicity”
George Carlin
I’m sure that’s just how some caterpillars feel, under-appreciated at best, reviled by many a homeowner at worst. Caterpillars are often seen as those critters that “eat my plants” without the person making the connection to their necessity in order to have the beautiful butterflies (and moths) that visit our gardens and pollinate so many plants. But I think caterpillars are just as beautiful as their adult forms and here are a few images that I hope will convince you of that as well.
Curve-lined Owlet backlit
By moving my light source around using my macro twin lights, I can get dramatically different results.
Curve-lined Owlet silhouette
By placing a white piece of foam core as a backdrop, you can highlight the outline.
Hog Sphinx
Some species have a translucent quality when light is shined on them from behind or the side.
Black-etched Prominent close up of prolegs
A close up shot often reveals beautiful combinations of the larva and its plant.
Spicebush Swallowtail caterpillar
And the winner in the make-up artist category is….the Spicebush Swallowtail. This is one caterpillar that looks like an artist painted it with bright colors and patterns. It hides in a leaf shelter pulled together by stretching silk across the leaf. Then it tucks its real head and arches making the fake eyes more pronounced to discourage predators.
Spicebush Swallowtail fake eye
The level of artistic detail on the fake eye is what amazes me – there is a light spot that makes the “eye” seem moist, heightening the illusion.
So, get outside this weekend and take a moment to look closely and appreciate the wonder and diversity that surrounds us. Take a moment to sit with a caterpillar and admire it. Prepare to be amazed.
Roads End Naturalist 