Tuesday, October 21, 2014

The Buck Moths ride again

Last weekend was a whirlwind tour of the state. I was in northeast Ohio on Saturday to give a talk for Summit County Metro Parks (thanks for having me, Meghan!). Since that program wasn't until 7 pm, I headed up early to visit some iconic natural areas and make some images.

In the photo above, we're looking off the massive bluffs of Hach-Otis State Nature Preserve. Fall color was nearing peak. I only regret that it was a rainy, overcast day. A bright blue sky day would have made the leaf color sizzle, but one takes what one gets.

The following day, it was up early and off to southern Ohio at the other end of the state. This view is from the Copperhead Lookout fire tower in Shawnee State Forest, and it's evident that fall color is not quite as advanced down there.

If you would like a suggestion for a last hurrah fall field trip, I'd suggest Shawnee this weekend. The leaf color should be outstanding, and as you shall see if you forge on with this post, there are other interesting things to observe.

Colorful Sugar Maple leaves brighten the ground.

While tree leaves are changing hues and falling to the ground, one of our most interesting treelets is bursting into bloom. Witch-hazel, Hamamelis virginiana, was in flower in both northern and southern Ohio last weekend. The spindly yellow flowers are easy to overlook among the fading leaves.

Long confetti-like petals radiate from the Witch-hazel's corolla - an odd looking flower indeed.

But to the subject at hand, Buck Moths, Hemileuca maia. I picked up my friend Grace Cochran in Chillicothe bright and early Sunday morning, and we went down to Shawnee to hunt bucks. To me, this large and interestingly marked moth is as much a sign of autumn's closure as anything. But only in certain regions, at least in Ohio. Buck Moths are limited to the hill country of southern and southeastern Ohio, and another population occurs in the Oak Openings west of Toledo.

To pursue Buck Moths, you've got to head afield late, after most moths are done for the year. They begin flying in mid-October or thereabouts, and can be found into November.

This is the Buck Moth caterpillar, and it is a voracious consumer of oaks. They are said to favor the foliage of trees in the red oak group. In any event, you want to seek the adult moths in forests heavily populated with oaks.

Antennae at half mast, a male Buck Moth seemingly glares at the photographer. Note the dense hair, which is almost furlike. Such a coat benefits an insect that flies this late in the season, when air temperatures may only be in the 50's F.

Buck Moths do have the good manners to fly during the day, which makes finding them fairly easy. Slowly cruising the forest roads of Shawnee is probably the easiest way to find them. Wait until you spot a moth winging by, park, and start chasing. Problem is, most of the moths that you see will be males in rabid pursuit of females. They rarely stop in their relentless tracking of pheromones, and all too often shoot by and off into the woods never to be seen again.

Like a good geek, I suppose, I keep an insect net in the trunk. Using that, I was able to bag a few moths for closer inspection. All were released unharmed, and off they went, right back on the females' trail.

Here we can see the exceptionally well-furred abdomen of a male Buck Moth. We know it is a male by the bright orange tassel adorning the tip of the abdomen. When captured, the moth will wag and curl the abdomen, and that behavior along with the bright colors may be intimidating to potential predators.

It isn't every fall that I can get out and pursue big Buck Moths, but fall isn't quite the same without such a Lepidopteran hunt. Thanks to Grace for helping to wrangle the moths, and for participating in the hunt.


Sunday, October 19, 2014

Fringed Gentians

As most plants decline, fringed gentians put on a show

October 19, 2014

Jim McCormac

Thou blossom bright with autumn dew,
And colored with the heaven’s own blue,
That openest when the quiet light
Succeeds the keen and frosty night.
— excerpted from To the Fringed Gentian by William Cullen Bryant

Fall’s frosty days are here, and colder weather and shorter days have muted autumn’s spectacular wildflowers.

Some flowers persist in a losing battle with Old Man Winter. The riotous bouquet of asters, colored in blue, white and purple, struggle mightily to hold on. Their rich hues are punctuated by lemony goldenrod flowers, another of winter’s botanical deniers.

None of fall’s holdouts compare, however, to the king of autumn flowers: the fringed gentian.

On Oct. 5, a date that seems too late for wildflower hunting, I visited a rich fen in Ross County. After a short trek through pasture and scruffy woods, we burst into a wet meadow browned with sedges. Breezy gusts showered leaves from the surrounding trees, and nippy air called for warm jackets.

In spite of the late date, we were greeted by one of Ohio’s most spectacular wildflower displays. Sprinkled among the senescent grasses and sedges were thousands of fringed gentians, just hitting their stride. Like cobalt bursts of botanical fireworks, their gorgeous blue flowers glittered throughout the meadow.

A fringed gentian blossom almost defies adequate description. It’s as if the petals have been spun from silk dyed the richest royal blue. The mythical seamstress craftily allowed the petals’ edges to tatter and fray, creating a look of artful sloppy elegance.

Gentians are named for King Gentius, a ruler of ancient Illyria (which included Albania, Greece and Macedonia). According to the Roman naturalist Pliny, Gentius first discovered the purported medicinal properties of this family.

The gentians constitute a big family, with some 1,600 species worldwide; Ohio is home to only 14 of them. Among their rank, the fringed gentians rule.

The species written about here is the western fringed gentian (Gentianopsis virgata). The eastern fringed gentian is similar; in fact, some botanists haggle about the plants’ uniqueness. Both are beautiful.
Fringed gentian is rare in Ohio. It was once found in 26 counties; today, the plants occur in perhaps half of them.

This species is picky about its haunts, growing only in boggy peatlands. A 1992 study published in The Ohio Journal of Science showed that 98 percent of Ohio’s peatlands have been destroyed since European settlement. Development of land for agricultural purposes was the major culprit.

The fringed gentian is a stunning icon of habitats that we have largely erased. Many of its associates have also become rare. The flowers of blue silk should serve as a reminder to protect what we still have.

Naturalist Jim McCormac writes a biweekly column for The Dispatch. He also writes about nature at www.jimmccormac.blogspot.com.


Wednesday, October 15, 2014

Mergansers make a comeback in the Mountain State

A rocky mountain stream is punctuated by a quiet pool near Summersville, West Virginia. My friend Rachel Davis, who lives not far from here, showed me this little park back in late September. The place was full of biodiversity. Not long after exiting the car we saw a cool bird, and it was time to flip from the landscape lens to something with a bit more pulling power.

A hen Common Merganser! To birders used to seeing this species in migration and winter, when they frequent large lakes and rivers, seeing one on a small creek might seem strange. But Common Mergansers nest along streams, and I suspect that this bird was a local breeder who hadn't yet left the mountains.

Common Mergansers are BIG ducks - a hefty one can weigh 3.5 lbs. - but in spite of their bulk, they nest in cavities. I wrote about Ohio's only significant breeding population RIGHT HERE.

They're also fish eaters, and finicky about the water quality of the streams that they nest along. Cut the buffering forests and fill the stream with sediment, and the mergansers vanish. Otherwise pollute their streams and damage the aquatic food chain, and it's curtains for the fish ducks. Common Mergansers make a good barometer of the health of the streams, rivers, and lakes where they breed.

I was surprised to see this merganser where it was, as I didn't know that they bred in the area. But to see one of these ducks on such a small stream, even this late in the season, might be an indicator of local nesting.

Map courtesy of Birds of North America Online

Here's a map depicting the North America distribution of Common Merganser. As is evident, they breed in a broad northerly swath, and northern Ohio is at the southernmost latitude for eastern nesters. West Virginia isn't even shown in the breeding range.

The map needs updated, but it would have been accurate not so long ago. During the first West Virginia Breeding Bird Atlas, which took place from 1984 to 1989, no evidence of nesting Common Mergansers was found in the Mountaineer State. Fast forward to Atlas II, which began in 2009 and concluded at the end of this year's field season. The merganser's status had changed dramatically, and for the better. The ducks were found in 68 blocks, mostly in the eastern half of the state, and nesting was confirmed in 35 of them. A positive environmental story in an age of all too common gloom and doom.

Common Mergansers undoubtedly bred historically in much of West Virginia. Rampant logging and the attendant degradation of streams probably pushed them out for decades, just as it did here in Ohio. As forests have recovered and the aquatic health of forest streams improved, the ducks have made a comeback.


Saturday, October 11, 2014

A murderous, mobile lichen

I've written about the larvae of the Green Lacewing, Leucochrysa pavida, before, but never with (what I felt) were adequate photographs. These little creatures are very hard to image. They're small, mostly covered up, and when they expose themselves they're generally on the move.

It was time to figure out how to overcome the photographic challenges. I'm involved in a project that features an essay about lacewing larvae, and a good photo was a must. Lacewing larvae of the type shown below are not rare, but can be a challenge to locate for reasons that will soon be obvious. I asked Chris Bedel, Director of the Edge of Appalachia Preserve, if he might keep an eye out for lacewing larvae and capture me some livestock if he found any. Chris did, and I was able to set up a shoot under more controlled conditions than one would find outside, on the trunk of a tree. My rig was the Canon 5D Mark III with the twin-lite flash setup rigged to the spectacular MP-E 65 mega-macro lens. Still wasn't easy, and I probably shot off a hundred shots to get a few keepers.

Not much to see here. At least that's what the lacewing wants you - or its victims - to think. Just a little roundish knot of lichens on a lichen-encrusted tree bark substrate.

Whoa! The little lichen ball lives! In one of the more remarkable cases of camouflage in the insect world, this predatory larva adorns its body with lichen bits. Not just any lichens, either. One study showed that only three species are typically selected. The lacewing is quite adept at harvesting these lichen bits, and swinging them up onto its dorsal surface, where they are webbed into place with silk.

The end result is a lichen Ghillie Suit. The insect moves with a halting stumble-step that might remind a birder of the curious mincing paces of an American Woodcock. Looking up under the costume, as here, we see that the lichens conceal a formidable predator. Check those mandibles!

Lacewing larvae of many species prey on aphids, and this one is no exception. Its only problem is that ants often guard arboreal aphid colonies, as the ants get a reward of nutrient-rich aphid honeydew for their troubles. Ants are extremely good at warding off threats to their charges; entomological pit bulls, you might say. The lacewing larva gets around this problem by means of its camouflaged suit. It moves right into aphid colonies, fooling the ant guards with its outstanding disguise. Other potential victims are no doubt fooled as well. Who would notice that the little lichen clump was slowly moving their way?

We go directly under the animal, and can better see how everything is put together. Not only is the lacewing incredibly well camouflaged, but it can also flex its body and pull the lichen suit into a protective shell if threatened. Under my macro lens, I could see the larvae occasionally harvest a lichen bit with the mandibles or labial palps - little feelers that extend forward from the head (it was hard to tell what parts were doing the grabbing) - and quickly place them on its back.

The death-dealing mandibles at the right are what the creature uses to seize its prey, which will then be punctured by the mouthparts and sucked dry. Radiating around its body are long struts capped with stiff hairlike bristles. These serve to support the lichen "house" on its back.

Should you be a lesser beast, you would not want to glance up and see this face looming from under the "harmless" clump of lichen.

If all goes well for the lacewing larva, it will eventually morph into a small but beautiful winged insect with gossamer net-veined wings that is extremely different than the animal seen here. If you search enough lichen-spackled tree trunks and limbs, eventually you'll make the acquaintance of one of these things.

Nature truly is amazing.

Thanks to Chris Bedel for his help in securing these lichen-lions!


Wednesday, October 8, 2014

Support the Big Sit!

The Big Sit! is an effort to tally as many bird species as possible within 24 hours, from the confines of an officially designated 17-foot diameter circle. The Big Sit! concept was formalized by the New Haven (Connecticut) Bird Club in 1993, and later Bird Watcher's Digest stepped in to provide sponsorship. I wrote in more detail about Big Sits in last Sunday's Columbus Dispatch, RIGHT HERE.

Big Sits are a lot of fun, and tax all of a birder's identification skills. They can also be used as an interesting way to raise funds for worthy causes. The Big Sit! occurs this coming weekend, October 11th & 12th, and well over 150 circles will be formed and sat in all across the States and beyond.

The Grange Insurance Audubon Center (GIAC) just south of downtown Columbus, Ohio. The center opened about five years ago, and one of its major missions is to expose kids to nature. Because of the center's location, it draws lots of inner city school kids, and helps to teach them about the natural world. That's a righteous cause, and one that I know of many of us are keenly interested in. Thus, I was flattered to be asked to join GIAC's board, and accepted of course.

The GIAC is about as environmentally friendly a building as one can construct, and that includes the vegetated roof, seen here. One day, I was gazing up at the structure, and the light bulb illuminated over my head. BIG SIT! The rooftop should be an ideal place to set up a 17-foot diameter circle and count away.

Fast forward and the time is nearly upon us. Along with Bill Heck, Columbus Audubon's immediate past president, ace birder Steve Landes (he found the recent mega-rarity Reddish Egret [CLICK HERE]), Suzan Jervey, and probably others, I'll be up on that roof A LOT come this Sunday, October 12th. You're free to join us for as little or as long as you wish, if you want to get in some sedentary birding. Our circle will be on the highest point of the roof, all the way to the back right in the photo. We (at least Bill and I, for starts) will take up position just after midnight this Sunday, and stay there (breaks are permitted!) well into the following evening. If it is a clear calm night, it's amazing how many species can be detected after dark by their calls.

This is the view from our circle, looking north and east. The field and wetlands draw a diversity of birds, and the Peregrine Falcons that hang out on downtown skyscrapers make occasional passes through the area.

Just west of the center is the mighty Scioto River, and its presence should mean lots of birds. This locale is a migratory freeway, and I bet we have a few dozen species checked off by sunrise. Because of the habitat diversity in view of the Big Sit circle, I'd think we will muster at least 60 species, and possibly many more than that. It'll be interesting to see what the total turns out to be.

Progress updates will be posted to the Grange Insurance Audubon Center's website, RIGHT HERE. As we tick new species, Jeff Yost and crew will post them to the site, along with information about the species.

Finally, we hope to raise a few bucks to support the center and its mission. A common way of donating to Big Sits is via a per-species pledge. Maybe it's $5.00 a species, $1.00 a species, or even a quarter a species. Every contribution is appreciated! If you would like to help fund our mission (madness), please visit the Grange Insurance Audubon Center website RIGHT HERE.

If you want more details about the Big Sit! or would like to come up on the roof for a bit, please email me at: jimmccormac35 AT gmail.com


Tuesday, October 7, 2014

Our most bizarre(?) caterpillar gets more bizarre

Earlier this fall, I wrote (with some excitement) about finally finding one of our strangest caterpillars, the Harris's Three-spot, Harrisimemna trisignata. That post, with photos, is RIGHT HERE. It describes the odd behavior of the caterpillar, and the equally strange appearance of the moth that it morphs into.

On a recent expedition into the New River Gorge area of West Virginia, I had the great experience of seeing another H. 3-spot. Rachel Davis and I ventured into the Wolf Creek Park wetland after dark, and Rachel spotted the beast above. She called me over, and WOW! We had stumbled into a 3-spot in the act of excavating its pupatorium.

That's right, the life cycle of this weird caterpillar gets even weirder. When it nears the end of the line for the caterpillar stage,the caterpillar bores a chamber into solid wood. We probably found this one not too long after it began digging, and at this point its chamber is deep enough to fit half its body in. The hole is being drilled into the untreated pine of a boardwalk railing.

The caterpillar emerges, perhaps to take a breather and glare at the nosy paparazzi. But this allows us to fully appreciate its truly odd appearance.

After waiting and watching for a good while, we learned that 3-spots tunnel quite slowly. So, we got bored, so to speak, and left. But I could not stand it and had to return the following evening to see what kind of progress had been made. We found that the caterpillar had deepened the hole to the point that it could now fit its entire body inside. In this shot, the tail end of the cat is all that is visible.

Evidence of its labors littered the boardwalk decking under the excavation. These little pellets are wood shavings, masticated and packed into globules. Having never witnessed this behavior - few people probably have - I was naturally curious as to how the caterpillar went about ejecting the excavated wood debris. We decided to wait and watch, and hoped that it would not be hours between pellet ejections.

Here comes the caterpillar, lugging a pellet. It grasps the pellet in its mandibles and thoracic prolegs, and tugs it from the depths.

 Out a bit further...

Seconds after I made this image, the caterpillar dropped the pellet to the boards below. From the time that we could first see the pellet apear to the time the cat dumped it was probably less than a minute. In general, it took about 20-30 minutes for it to fully form a pellet and bring it back to the burrow entrance and dump it. As the excavation deepened, the time between pellets seemed to increase. Presumably the caterpillar digs a wider chamber at the tunnel's end. Remember, the adult moth must emerge from this pupatorium next year.

Here's a close-up of a pellet. Well chewed wood softened and loosely packed together. Harris's Three-spots must have very powerful mandibles.

The small red arrow points down to the tunnel entrance. The boardwalk handrail provides a size context. I'm assuming that the caterpillar does its boring under cover of darkness, but we did not visit during daylight hours to see if anything was happening.

Photo: Rachel Davis

Rachel, whose office is in nearby Fayetteville, went back two days later to see what the tunnel looked like. It was done, and expertly sealed. While the entrance looks to be solidly plugged with wood, the cap is actually a thin veneer of silk produced by the caterpillar. Remember, the moth must somehow escape the tunnel late next spring, and apparently it can punch its way through this silk operculum. The silken cover disguises the pupatorium entrance well, and few if any creatures would probably pay it any mind.

David Wagner, in his ground-breaking book Caterpillars of Eastern North America, notes that Harris's Three-spot caterpillars consume a great many species of common woody plants. Yet the caterpillars/moths seem rare. In spite of years of searching, it wasn't until this year that I finally found this species. Many caterpillar hunters that I know have never seen one. I think the creation of its pupal chamber may be the species' Achilles heel. Spending two nights making the chamber leaves the caterpillar quite vulnerable to predators, and it seems likely that many would be picked off at this stage. However, if the caterpillar successfully completes the burrow and seals itself in, it is probably as safe as a caterpillar can be.


Saturday, October 4, 2014

Caterpillar curios

Much cooler nights, shorter days, and foliage in a rapid state of senescence means the end of caterpillar season. It'll be a long cold winter with little or no prey for us caterpillar hunters. Following is a hodgepodge of caterpillars found in the last few weeks, mostly from Adams County, Ohio, but a few from elsewhere in the state. May they help tide you over during the sleet, snow, and blizzards to come.

Striking in its complexity is this very showy Honey Locust Moth caterpillar, Sphingicampa bicolor. John Howard has a prime honey locust tree on his property, and seems to find the cats on it every year. He was good enough to bring this specimen along on one of our field trips so that interested parties could photograph it. As is always the case, click on the photo to ENLARGE it.

These are two of the four anterior prolegs of the above caterpillar. They are like small suction cups tipped with little hooks called crochets, and the prolegs exert a very powerful grip on twigs or foliage.

Here is the anterior prolegs of a Giant Leopard Moth, Hypercompe scribonia.These crochets are quite well developed, and are clearly visible in the photo. It appears that the caterpillar interlaces the crochets of the opposing feet, thus creating a nearly unbreakable grasp on the twig or petiole.

The White-blotched Hetercampa, Heterocampa umbrata, is a strange beast indeed. When alarmed, it elevates its posterior, or at least this one did. Like many caterpillar species, it is dappled with paler areas that seemingly mimic dead or necrotic leaf tissue and help it blend with its surroundings. This is one of many oak specialist caterpillars, and our model was feeding on Black Oak, Quercus velutina.

If possible, this Red-washed Prominent, Oligocentria semirufescens, is stranger than the previous character. A stegosaurus comes to mind. While rather conspicuous in this pose, if the caterpillar has chewed its way into the margin of a leaf, it blends in incredibly well.

I was fortunate indeed to luck into this scene. It is a Black-waved Flannel Moth caterpillar, Megalopyge crispata, in the process of molting. Most caterpillars go through five molts - some species even more - and each stage is termed an instar. This flannel cat is just entering its ultimate instar, which is brown and shaggy. Prior to this stage, it was like a big puffball of white hair, as seen by the old skin on the right. Whatever stage they are in, don't touch! This caterpillar is armed with very painful stinging spines.

Handsome but rather unassuming is this Walnut Sphinx, Amorpha juglandis, seen here, appropriately, on a black walnut tree. When threatened, it puts on a heckuva show. Touch one and it will expel air through its spiracles (tiny openings for air exchange) with great force. The result is a quite audible and utterly unexpected hissing sound. That effect is coupled with violent side to side thrashing. It's enough to encourage many would-be predators to leave the caterpillar alone, I'd think.

This Hog Sphinx, Darapsa myron, did not have enough defensive ploys to successfully thwart braconid wasps, which have parastized it. The cylindric cottony capsule is a wasp cocoon, and all of the little brown spots mark the locations of cocoons that have fallen off. The wasp grubs ate their way to maturity inside the caterpillar host, then burst through the skin and formed these cocoons. In short order, they'll pop the tops off the cocoons and emerge as adult wasps. This caterpillar, while still alive, is unlikely to survive such ravages. The vast majority of caterpillars perish due to predators, but fortunately enough survive to complete the life cycle and repopulate our world with moths and butterflies.