"Caterpillar Roundup" weekend

 

I made this iPhone snap last Saturday morning, as part of our crew puts the finishing touches on the caterpillar exhibit at the Arc of Appalachia's Forest Museum, in Highland County, Ohio, near Bainbridge.

At least ten years ago and probably longer ago than that, John Howard and I - as best that I can recall - began gathering a few larvally-minded friends to seek caterpillars in Adams and Scioto counties. We would choose somewhere around the first weekend in September, as that's when caterpillar diversity and biomass is at its peak.

Why? That's a legitimate question, with a multi-pronged answer. Foremost, caterpillars - the larval stage of butterflies and moths - are INCREDIBLY ecologically important. The lepidoptera is one of the world's largest orders of animals, and of their ranks, moths overwhelm butterflies in species diversity. In our part of the world, which is dominated by the Eastern Deciduous Forest ecosystem, moths, and to a far lesser extent, butterflies, play an incredibly important role in food webs, pollination, and the evolution of plants. Yet nearly no one is aware of this.

Two, as photographic fodder, caterpillars are hard to beat. Low-hanging fruit subjects such as deer, eagles, cranes, etc. are beat to death, in a way. There are scads of photos of such easily found fare and if you hit some popular Osprey nest or whatever, there's liable to be a crowd of people shooting the exact same thing. Nothing wrong with that, and I love shooting that stuff, too. But caterpillars, in all their magnificent photogenic glory, represent far more of a photographic wild west. I'll let the photos of various larvae in this post and following ones speak for themselves.

Three, there is the thrill of the hunt. Most caterpillars are far more active nocturnally, behavior no doubt driven by the legions of diurnal sharp-eyed birds that hunt them. A better than passing knowledge of botany is also an enormous asset, as most caterpillar species are tightly wedded to a small group of flora, sometimes only one species. So, one must venture out after nightfall, botanically interpret the habitats, and seek the larval game. We are greatly aided in this by the evolution of blacklight flashlights, which constantly get better - and less expensive. Many caterpillars fluoresce brightly under UV light, to the point that they look like they've been plugged into a light socket.

Several years ago, we switched our hunting grounds to the Arc of Appalachia properties in Highland County, which gave us access to their various lodging, and the Forest Museum as a base camp. That led to the creation of the Arc's Caterpillar Roundup, in which the public is invited in from 10am to 4pm on Saturday. Select species of larvae that our crew found the previous night is brought into the museum and exhibited on appropriate host plants. This year, nearly 150 people came and were exposed to the wonders and ecological importance of the tubular crowd. It's been wonderful, the addition of this educational element to our caterpillar-hunting safari. Visitors also have the added allure of hiking through some of the most gorgeous habitats to be found in Ohio, and some of those trails are right outside the museum.

NOTE: All caterpillars, following their public day in the sun, are released back into the wild, on appropriate host plants. No one dies, at least if we can help it (some caterpillars have been parasitized by flies or wasps, but those just provide more teachable moments). For their part, the captive cats normally just eat away, and produce prodigious quantities of frass. Frass is caterpillar poop: hard, dry little pellets of indigestible plant matter. Shauna Weyrauch had a great idea for next year: Collect all the frass pellets in a jar rather than brushing them into the waste bin. It'll be a big jar's worth, I am sure, as we normally exhibit dozens of caterpillars. And yet another teachable moment. Due to thousands upon thousands of caterpillars feeding in the woodlands, there is essentially a gentle fecal rain, and all those frass pellets go back into the soil as fertilizer.

PHOTO NOTES: My caterpillar rig is the Canon R5, Canon's 100mm f/2.8 macro lens, and that same company's MT-24EX twin lite flash system. The flashes have plastic diffusers to soften the light. I like the twin lites for their versatility, and because they have pre-lights. A half tap of the shutter button activates the soft pre-lights, which allow me to focus in complete darkness without the help of a flashlight. Settings, which I rarely deviate from, are f/16, ISO 200, and 1/200 second. The latter is the camera's flash sync speed, and it's plenty fast enough. The lens' excellent image stabilizer is activated, as I'm shooting handheld for most shots. When shooting detained livestock indoors, I sometimes deviate and do some work with no flash and even use a mini-tripod for some work. In those cases, I might go down to less than a second exposure time, as long as my subject is inert. While I am not generally a big flash fan, especially for subjects such as plants, with insects it can be very useful in creating sharper, more detailed images, especially at small apertures such as f/16. For nocturnal work such as shooting caterpillar in situ, flash is essential.

Okay, on to the rogue's gallery of caterpillars...

As always, click the image to enlarge

Two last instar Imperial Moth caterpillars (Eacles imperialis) nosh on White Pine (Pinus strobus). It was a rare opportunity to photograph both green and cinnamon forms together. Some of our people raise caterpillars and will bring livestock to ensure the public gets to see them in case we fail to find any in the wild. Mary Ann Maier brought these. The big silkmoth cats, like this species, are major crowd-pleasers. 

NOTE: "Instar" is the term for a stage of development in a caterpillar. They grow through molting, often five molts for larger species, and the stage between molts is an instar.

Another spectacular silkmoth, the Io Moth (Automeris io). I made this shot indoors, using a mini-tripod for stabilization. Settings were f/11, ISO 400, and 1/6 second exposure with no flash. The cat never budged so a ridiculously slow shutter speed was possible. Note the showy fascicles of spines on the cat. Brush them, and it feels like you rubbed up against a powerful stinging nettle. Best not to handle caterpillars with spines, especially if you don't know what they are.

A Crowned Slug (Isa textula) ensconced on an oak leaf. Small but extraordinary, the creature looks like it came off a coral reef. The slug moth caterpillars are a bizarre lot, and always a hit among caterpillar hunters.

We were indeed pleased to see, and have the opportunity to photograph, this little gem. It's the caterpillar of a butterfly, too, while the overwhelming majority of species in this series of posts are moths. John Howard had found it the preceding day and brought it back for everyone to see.

It is a Juniper Hairstreak (Callophrys gryneus), an extreme specialist. The cats, at least in our part of the world, eat only Red Cedar (Juniperus virginiana). The caterpillar is also a great example of botanical mimicry, as they match the cedar needles to a remarkable degree, both in color and form.

A larger-scale view of the hairstreak cat. They can be quite difficult to spot when ensconced deep among the needles.

This one could win a larval beauty pageant and is always high on our wish list. It is a Honey Locust Moth caterpillar (Syssphinx bicolor) and it is well named. I have only seen the caterpillars feeding on Honey Locust (Gleditsia triacanthos) although I have seen reports of it feeding on the closely allied Kentucky Coffee Tree (Gymnocladus dioicus).

An American Dagger caterpillar (Acronicta americana). It has just shed, and the yellower molt to the right is the cast-off skin of the previous instar. American Daggers are polyphagous, easting scores of different plant species, and are often one of the most common caterpillars that we find on nocturnal forays. I would note that polyphagous (many plants) diets are not the norm in the caterpillar world, specialization is.

The caterpillar of a Dot-lined White (Artace cribaria) becomes one with the branch that it's on. This is botanical mimicry writ large, although perhaps in this case it is lichen mimicry. I would note that iNaturalist's amazing identification app, when confronted with photos of this caterpillar, invariably only suggests various lichens as possibilities. I sometimes wonder how many of these we walk right past.

The stunning Radcliffe's Dagger caterpillar (Acronicta radcliffei) with its incredible bulbous black and red head. This species is a specialist on woody plants in the rose family (Rosaceae), particularly cherries. I think this one was found on a Black Cherry (Prunus serotina). Even though it isn't thought to be rare, I believe this was only the second one I've seen. We sometimes wonder if various caterpillar species, maybe this one included, occur primarily in the canopies of the trees in which they feed, out of view of ground-bound humans.

Always a coveted find, the Saddleback Caterpillar (Acharea stimulea). It isn't rare, in part because the caterpillars are polyphagous and can consume a large number of common plant species. Nonetheless, this must be a boom year for them, as our group must have found two dozen or so, far more than would be usual.

Note those fascicles of stiff spines. Some say that this species may have the most punishing sting of any North American caterpillar, and people with greater sensitivity to its venom can react very badly. They are envenomating spines. When triggered by touch, the spine injects venom from a sac at is base, much like a hypodermic syringe. I am told that the pain comes instantly, it is fierce and lasts for some time. Newbies, upon first seeing a Saddleback, usually call it cute. That they are, but potentially painfully cute.

That's it for now, but more cats are to follow...

Epic caterpillaring results in many cool finds

 

Cherry Dagger moth caterpillar (Acronicta hasta)

Shauna and I spent last weekend at the fabulous Highlands Nature Sanctuary in Highland County, Ohio, which is owned by the Arc of Appalachia. A bunch of us were there for our 12th annual "caterpillar safari", which is just a bunch of larvally-minded friends of ecology gathering to seek out the always fascinating caterpillars of moths (mostly) and butterflies (far fewer in numbers and diversity). Now is peak season for caterpillar abundance and diversity, and we prowled into the wee hours on Friday and Saturday nights, exploring interesting habitats. Most caterpillars are active nocturnally, so hunters of them must adjust their search hours accordingly.

Dozens of species of caterpillars were found and photographed, including this Cherry Dagger (Acronicta hasta). We brought lots of livestock back to the Arc's forest museum - our base camp - and from 10 am - 2 pm the public is invited in. Dozens of people got to see crazy larvae that they likely never knew existed. One should not underestimate the value of moth larvae (which the overwhelming number of caterpillars are). They are the primary organisms that convert plant matter into a digestible form of protein for birds and myriad other animals and underpin food webs.

Gray Hairstreak caterpillar (Strymon melinus)

We certainly do not ignore the occasional butterfly caterpillar that turns up, and this was a particularly interesting one. It is the caterpillar of the Gray Hairstreak (Strymon melinus), which specializes on feeding upon species in the Pea Family (Fabaceae). These cats resemble Mike & Ike candies and are tiny and easily overlooked.

This one is feeding on a tick-trefoil in the genus Desmodium. Many hikers know this group of plants by their triangular loments (fruit) that are thickly beset with stout hooked hairs. They evolved for mammalian dispersal, and that includes the clothing worn by humans. Those loments can be tough to get off and will even survive trips through the washing machine.

Here's what that Gray Hairstreak caterpillar in the previous image will (hopefully) morph into - one of our showiest butterflies. I say "hopefully" because the survivorship of caterpillars is astonishingly low. Just about everything wants to eat them and for some species of moths, at least, probably only one percent or so of caterpillars make it through the complete life cycle and to the mature reproductive stage. The rest become part of a great food chain. To compensate for such high mortality, butterflies and moths lay enormous numbers of eggs; a carpet-bombing strategy if you will.

Finally, a cool little-known thing about Gray Hairstreak butterflies. John Howard showed this to me a while back. Hairstreaks habitually rub their hind wings together, and the "tails" resemble antennae. Perhaps this pseudo face with its twitching antennae fools birds and other would-be predators who then lunge at the wrong end of the butterfly. While the hairstreak may lose parts of its hind wings, it might still escape to live another day and find a mate and reproduce.

Anyway, as John pointed out, if you can get directly behind the hairstreak and under it (that can take some effort), the lateral fringes form the illusion of orange eyes capped with long antennae, and even a frowning mouth below. Whether all of that evolved to spook visual predators I do not know, but whatever the case it certainly looks cool. And once a butterfly photographer knows this, they may find themselves spending much time attempting to get into position to get this shot.

Pyramid of trilliums

As always, click the image to enlarge

A pyramid of Large-flowered Trillium (Trillium grandiflorum). It appears as if a fissure in the cliff above opened, and scores of beautiful flowers tumbled out. I made this image yesterday, April 11, at the amazing Highlands Nature Sanctuary, owned by the Arc of Appalachia.

Lush forest floors such as this, with rich soft humus and deep leaf litter, are becoming increasingly rare. The ravages of repeated logging operations with their attendant soil compaction, disruption of subterranean fungal communities, and alteration of natural drainage patterns, is increasingly taking its toll on most of our woodlands. An overabundance of White-tailed Deer - one of the rare "winners" in a world heavily altered by man's hand - has all too often decimated woodland herbaceous layers, and deer really love trillium. On the other hand, the fabulous forest partridge, the Ruffed Grouse, is rapidly blinking out. Game managers attribute its loss to a lack of early successional woodlands and promote yet more logging to restore grouse habitat. Little do they know that their cure is likely the very reason the grouse have vanished.

I highly recommend a visit to Highlands Nature Sanctuary and other Arc of Appalachia sites. Their work represents true conservation. Not the hubris of people deciding which species are important and which aren't and engaging in foolhardy management practices geared towards extracting maximum monetary value from our natural resources.

A floristic throwback to Spring

As I write this, here in Central Ohio, it is lightly snowing and the temperature is around freezing. While I am a big fan of winter, snow, and cold weather, when the days become as short as they do this time of year I pine for spring and the resurgence of plant life.

On April 14 last spring, I made a foray into Highland County and the amazing Highlands Nature Sanctuary and environs. This amazing place - and many others - are owned and managed by the Arc of Appalachia. If you want to donate to a worthy cause, this nonprofit private conservation organization would be a winner. GO HERE for more info on the Arc.

The gorge pictured above was new to me. I dubbed it "The Jumbles" as the small stream wends a torturous path through massive limestone slump blocks calved from surrounding cliffs. The boulders were carpeted with moss, and wildflowers grew in profusion from the rocks. The place is magical.

One site in this area harbors a wonderful population of Shooting-star, Dodecatheon meadia. It was just starting to flower and of course some images had to be made. Most plants here have rosy-pink flowers, and are arguably even more striking than the more commonly encountered white form.

PHOTOGRAPHY NOTE: This image and the following were made with Canon's 70-200mm f/2.8 II lens. It is superb for many types of shots, and I have taken to using it frequently to shoot wildflowers. I will usually sandwich either a 12mm or 25mm extension tube between camera and lens to allow for closer focusing. Sometimes I even use larger telephotos. I love the beautiful soft bokeh that these lenses impart to the background, and usually shoot at more open apertures such as f/5.6 or f/7.1. The rig is mounted on a tripod, and I shoot in live view with a 2-second shutter delay so there is absolutely no movement, at least on my part. Breezes are another story, and yet another reason why it's good to get out really early, when winds are often nil or mild.

A trio of Large-flowered Trillium, Trillium grandiflorum, bunched together and fresh as can be. This common vernal wildflower is one of spring's botanical highlights and I never tire of them no matter how many I have seen. While shooting individual plants like these is fun, I was after a bigger trillia treasure, a spot that I long had known about but had never clapped eyes on...

Whoa! A torrent of trillium cascades down a wooded slope, seemingly pouring from a fissure in the overarching limestone cliff. This spectacle is jaw-dropping remarkable, and just reflecting back on the situation via this photo makes thoughts of sleet and winter fade.

Spring will be on us before we know it. It's always such a great time of year, as the flora shakes off its winter slumber and pops forth with a vengeance.
 

Rare flowering plant finds safe haven in southern Ohio

Sullivant's coolwort was discovered in 1839 in Highland County

Columbus Dispatch

July 29, 2018

NATURE

Jim McCormac

In 1795, Lucas Sullivant was contracted by the Commonwealth of Virginia to survey land along the Scioto River in what’s now Franklin County and vicinity. Following that task, he took a hiatus in Kentucky but returned in 1797 and platted out Franklinton.Sullivant’s settlement would become Columbus, and his name is immortalized by the busy West Side avenue that bears his name.

Lucas and his wife Sarah had the first of their four children on Jan. 15, 1803 — just a month before President Thomas Jefferson signed papers recognizing Ohio’s constitution and boundaries. Their first child was William Starling Sullivant, and he would go on to achieve great things in the natural sciences.

William was born into a still wild frontier, at a time when new species of plants regularly turned up. He turned into quite the botanist, avidly exploring various habitats around his central Ohio home.

In the summer of 1839 while visiting Highland County — quite the excursion back then — Sullivant explored massive limestone cliffs overlooking the Paint Creek Valley. There he met with a delicate little plant unknown to him, growing in fissures high on the rock faces.

Sullivant’s mystery plant was new to science. It would be dubbed Sullivantia sullivantii, named in his honor by the great botanist Asa Gray in 1840. Today, the plant is often referred to by a common name, Sullivant’s coolwort. It is only known from a smattering of sites in nine states.

The place where a plant or animal is first discovered is called a “type locality,” and the expansion of the human population has not been kind to most type localities in the eastern United States. The cliffs where Sullivant discovered his coolwort were flooded in 1974 following completion of the Paint Creek Lake dam.

I recently visited an amazing place, the Highlands Nature Sanctuary in eastern Highland County. It is owned by the Arc of Appalachia, a private conservation organization that has thus far protected nearly 6,000 acres of natural areas. Highlands Nature Sanctuary is a crown jewel among the Arc’s 18 preserves.

Rocky Fork Gorge forms the spectacular centerpiece of Highlands Nature Sanctuary, and its sheer cliffs support thriving populations of Sullivant’s coolwort. This little saxifrage is finicky. It grows only where seepages keep the shaded rock faces in a state of constant moisture.

Delicate spikes bearing tiny white flowers rise a few inches above glossy leaves. In places, the coolwort was so plentiful as to form hanging gardens on the otherwise barren rocky walls.

The Highlands Nature Sanctuary is only a mile from the site of Sullivant’s original discovery. I’m sure Sullivant would be pleased to know that the Arc of Appalachia is safeguarding his plant. After all, he was so smitten with the coolwort that its likeness was etched into his wife Eliza’s grave marker, in Green Lawn Cemetery on Columbus’s South Side.

Visitors are welcome at Highlands Nature Sanctuary. It’s a trip you’ll not regret. To learn more, visit: arcofappalachia.org.

Naturalist Jim McCormac writes a column for The Dispatch on the first, third and fifth Sundays of the month. He also writes about nature at www.jimmccormac.blogspot.com.