Sunday, December 31, 2023

Nature: Tiny southern flying squirrels a sight to behold

A southern flying squirrel/Jim McCormac

Nature: Tiny southern flying squirrels a sight to behold

Columbus Dispatch
December 31, 2023

NATURE
Jim McCormac

Six long years have elapsed since I last wrote about southern flying squirrels. That column ran on Dec. 31, 2017, and was made possible by the doyen of flying squirrels, Professor Don Althoff of the University of Rio Grande.

Althoff has devoted a big chunk of his career to studying flying squirrels and may have handled more of them than anyone. Over approximately 25 years of working with them, Althoff has laid hands on over 3,300 squirrels. The vast majority of people reading this have probably never seen one!

The southern flying squirrel — there is a northern species, from about central Michigan northward — is one of Ohio’s most common squirrels. Prior to settlement, it would have been the most common squirrel by far. It favors heavily wooded areas, and in such regions of the state it still is the most frequent squirrel species.

Flying squirrels are strictly nocturnal, and roost in tree cavities during the day. They’ll take readily to artificial boxes though, and will even nest in them. Althoff has 400 boxes in “trails” of 25 boxes each, distributed between eight sites in five southeastern counties. He and his helpers check each box during the months of January and February.

On Dec. 19, Shauna Weyrauch and I attended a box check. Shauna is an Ohio State University researcher who works with bobcats but is intensely interested in all mammals. I figured this outing would produce her “life” flying squirrel. We met up with Althoff and 15 of his helpers on a frosty morning along a backroad in Hocking County. If 15 helpers seems like a lot, well, you’d have to know Althoff. Charismatic and engaging, he draws people in with his passion for squirrels and the entirety of nature, as well as his breadth of knowledge. The promise of seeing “Rocky” in the flesh is certainly an allure, although you’ll have to go further afield to see Bullwinkle.

The Hocking County squirrel trail commences with a long steep uphill slog to a ridgetop carpeted with oaks, hickories and other trees. As each box is mounted 12 to 15 feet up a tree trunk, a ladder is part of the equipment. Trying to keep pace with the 69-year-old Althoff, ladder over his shoulder, as he navigates the rough terrain, can be challenging. Even for his much younger assistants.

Upon reaching a box, standard modus operandi is to place the ladder, then Althoff ascends, cork in pocket. Upon reaching the box he quickly plugs the entrance/exit hole with the cork, then opens the front of the box to expose the innards. A mesh screen prevents occupants from escaping. Our first eight boxes had no squirrels, but shredded bark and cored acorn and hickory nuts — sure evidence of squirrel tenants — were in most of them.

The ninth box was a jackpot — seven squirrels! Later we found another box with six squirrels, for a 13-squirrel day. Flying squirrels are quite social and typically roost together. Don’s record is 13 animals in one box. By huddling together, they create a warm furry quilt and their collective body heat warms the box to a temperature significantly higher than that outside the box.

A box with squirrels is taken to the ground, where an impromptu lab is set up. One at a time, the squirrels are shunted out of the box through a clear pipe and into a bag. A handler wearing thick gloves — squirrels can bite HARD — then removes the animal. It is weighed, detailed photos are taken, and a small metal ear clip is attached. The latter allows for positive identification of recaptures. The oldest squirrel Althoff has documented was about six years old. That’s two to three times the probable average life span. Finally, the squirrel is placed on a nearby tree trunk. They normally quickly ascend to a high limb, get their bearings, and then often leap into space, thrilling the observers with an impressive twisting glide to a distant tree.

Up close, flying squirrels are tiny but impressive. The biggest — pregnant females — weigh about 100 grams. The average weight is approximately 75 grams. That’s about the same as a large chicken egg. Disproportionately large dark eyes lend a “cute” (nearly everyone uses that adjective) look to the squirrel. A flattened miniature beaver tail serves as an aerial rudder. While mostly invisible at rest, membranous folds of skin stretch between the forelegs and hindlegs. When on glides, these membranes, known as patagium, transform the squirrel into a highly efficient paraglider. Flights can encompass several hundred feet and involve impressive twists and turns.

Hundreds of people have thus far participated in Althoff’s squirrel surveys. The vast majority have seen the flyers up close and personal and been dazzled by the exquisite little aeronauts, just as Shauna and I were. Here’s to many more squirrels for the indefatigable Althoff, doyen of the squirrels.

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

Professor Don Althoff checks a flying squirrel box/Jim McCormac

Friday, December 29, 2023

A few more Short-eared Owl images

Incoming Short-eared Owl. The last thing that a Meadow Vole wants to look up and see. As the light was fairly horrific yet the owling was great, I looked forward to a return visit to the site in the previous post. So, after seeing reports of breaking skies and some sunshine towards day's end Wednesday (12/27/2023), Shauna Weyrauch and I headed to Owlsville. The owls certainly didn't disappoint but the weather (and its forecasters) did. The predictions were way off base, and it was misty, foggy, and skies were even darker than during the preceding trip.

Such conditions made photography tough, but who cares? Numerous short-eared worked the fields, and at least as many Northern Harriers. There were many hostile interactions between the owls, and owls and harriers. At times, the angry terrier-like barks and low screams of owls rang out everywhere, mixed with the shrill whistles of the harriers. Not to mention the observation of a vole-caching, as described in the previous post. Just watching the action is great fun.

A Short-eared Owl glares (menacingly? it doesn't look too menacing, but I'm not a vole) at the camera. As sunset approached and the light grew even worse, we headed down the road to see how many owls we could tally, not thinking that any additional photography would bear fruit. We didn't get far before encountering the individual above, perched obliging at eye level and very near the road. The bird cared not a whit about our presence and continued surveilling for other owls, and harriers, while presumably also watching for voles. I got the vehicle into a good position, killed the engine and we began shooting out the windows.

It became apparent that the owl wasn't concerned with us. These owls are fairly tame, but this individual was unusually so. As the light was now really poor, we began playing with much lower shutter speeds to keep the ISO down. Shauna had it best as the owl happened to be on her side of the vehicle and she could use the door as a de facto tripod and brace her rig on the sill while using the vehicle as a blind of sorts.

PHOTO NOTES: Eventually I decided to slowly, quietly and carefully exit the vehicle, get my tripod out, and mount the rig on that. No issues, the owl didn't react. Thus stabilized, I was able to drop my shutter speed WAY down and still obtain sharp images. The image above was shot at 1/50 of a second at f/5.6, which gave an ISO of 1250. My Canon R5 handles higher ISOs well, and 1250 isn't too tough on it, and applying Topaz Denoise later helped clean up the image even more. Other than occasional turns of its head, the owl didn't move, so as long as I didn't fire while it was turning its head the bird might as well have been a feathered rock, especially as there was no wind. The previous image - of the same owl - was shot at 1/400 at f/5.6 (that aperture is wide-open on my Canon 800 lens) and that yielded an ISO of 1/5000. That image was made earlier in the sequence, before I bottomed out at 1/50. It is decidedly "noisier" than the image directly above, but it isn't too apparent as not much cropping was required.

Naturally the first image had to be at a much higher shutter speed, to freeze the flying bird. I went as low as I felt that I could work with and still obtain sharp images, which was 1,250 of a second. Again, at f/5.6 (I shot everything wide open on this dim later afternoon) and that produced an ISO of 10000. FAR higher than I like but there was nothing to be done about it. Fortunately, the bird came very near, and I got my shot when it was quite close, thus eliminating the need for heavy cropping which greatly intensifies noise caused by high ISO values.

In hindsight regarding the perched bird, I should have switched to 2-second timer delay and used touch screen focus. By doing so, I could have just touched the rear screen where the owl's head was (ALWAYS want eyes to be sharp). The touch would trigger the shot sequence to commence, and two seconds later the camera would fire, after any slight movement I might have caused while touching the camera to set focus would have stopped. About the only thing that could go awry is if the owl moved during my exposure, but if so, I would just retake another. By doing this, I could have experimented with exposures as low as 1/30 or 1/25, maybe even 1/10, and thus dropped the ISO much more while probably still managing sharp photos.

Monday, December 25, 2023

Short-eared Owls

 

A Short-eared Owl (Asio flammeus) watches for prey from atop a Honey Locust sapling. It was in the midst of hundreds of acres of grasslands. At least ten other owls shared its haunts, and at least as many Northern Harriers (Circus cyaneus).

A favored winter activity of birders, your narrator included, is watching Short-eared Owls. The charismatic raptors move southward from their breeding grounds in cyclically varying numbers. Some years, like this, there are lots of short-eareds about (at least in Ohio). In other winters relatively few are to be found.

On December 22, I made a trip to an area in north-central Ohio that is playing host to many owls. They were on the wing by 4 pm, but heavy cloud cover meant the light was poor. So, killer photos were not possible, but I share some documentary images here.

A Short-eared Owl sits atop a road sign. As long as observers are quiet, the owls pay us little mind. I crept up on this bird in the vehicle, was able to get to about 30 feet from it, kill the motor, and watch. It was beyond dusk by this time, and light was extremely poor. Much post-processing was necessary to make the image presentable. But making great owl pictures is at best half the fun. Photos or not, Short-eared Owls are charismatic and always interesting to watch.

I was pleased to see that an owl would habitually return to hunt from that locust sapling in the first photo. It meant that there would be plenty of action. Short-eared Owls are fiercely anti-social when hunting, seem to maintain loose territories, and don't hesitate to scrap with other owls (or other raptors). Several times passing owls would drop down to take a swipe at the bird in the locust. That triggered locust-owl to shoot aloft and engage the other in a dogfight, as above. Such squabbles are an aural treat, as the owls bark like angry terrier dogs, and emit low cat-like screams.

A short-ear on the hunt. Incredibly acute eyesight and hearing enable them to pick up the slightest movements and sounds caused by rodents below.

Quick as a wink, this owl pirouetted on a dime and dropped hard into the grasses. I saw many such hunting attempts this evening, and nary a bird came up with prey. The miss rate is often very high.

This is a Meadow Vole (Microtus pennsylvanicus) runway. The burly little rodents are probably the primary prey source for Short-eared Owls and Northern Harriers, at least in these grassland habitats. Vole runways, or raceways, are tunnels in the grass that mostly are hidden by a grassy roof. Occasional openings, as above, will briefly reveal the rodent to raptors coursing overhead.

But I do not think that the owls need to rely on visual identification of prey items such as voles. They likely hear the rodents scurrying through the tunnels, or perhaps gnawing on vegetation. Even with the fine-tuned senses of a Short-eared Owl, it would still be a tall order to pounce unerringly on a vole, sight unseen, especially if it is moving. This may explain the seemingly high miss rate, although rest assured, the owls get many, many voles.

A Meadow Vole dares to peek from a runway. A dash across open ground when lots of raptors are present is a suicide mission for the chunky rodents. Better to stay in the tunnels to up one's survival potential.

Meadow Voles have marked boom and bust cycles. Peaks can occur anywhere from every other year to every third or fourth year. The reasons for these fluctuations are imperfectly understood, but one thing is for sure: raptors quickly pick up on areas rich in the rodents. It has been claimed that at least some raptor species can detect vole urine trails visually, as their eyes can detect ultraviolet reflections in urinary compounds. Thus, the birds would view urine trails as easily seen purple squiggles, thus allowing vole-hunting raptors to quickly ascertain areas of food abundance and forgo areas with a paucity of prey. Much has been written about vole urine/UV/raptors, such AS THIS.

This all makes for a great story, except it may not be accurate. CLICK HERE for a paper that delineates the ability of select raptor species' ability to see into the reflective range of ultraviolet light, and how that compares with UV reflectance from vole urine. It may just be that avian vole-hunters such as Short-eared Owls, Northern Harriers, American Kestrels, and Rough-legged Hawks simply find troves of voles through their extraordinary vision, abetted in the case of the owl and harrier with highly attuned hearing. I have been in sites experiencing very high vole numbers on several occasions, and it was not difficult to detect voles, so many were racing about. Raptors, with their far sharper vision and ability to get an overhead perspective, undoubtedly quickly assess vole populations.

UV-reflective vole urine aside, Short-eared Owl watching is great fun (except for the voles). I hope you get to experience some of these charismatic hooters this winter.


Friday, December 22, 2023

Field Sparrow, in winter

 

A Field Sparrow (Spizella pusilla), distinctive with its pinkish bill, reddish cap, and white eye ring, on a frosty morning. During the breeding season, males deliver a beautifully melodic trilled song. In winter, Field Sparrows become far less conspicuous and skulk in old fields and brushy successional habitats. Ohio is at the northern limits of their wintering range and numbers seem to vary considerably from year to year. Last Saturday, December 16, while doing the Beaver Valley Christmas Bird Count in Jackson County, Shauna Weyrauch and I located 21 Field Sparrows - a personal record for a CBC. P.S.: The bill has grass seed stuck to it, hence the oddly misshapen look. Field Sparrows are big consumers of grass fruit.

Tuesday, December 19, 2023

Nature: Teeny-tiny golden-crowned kinglets are small, yes, but tough as nails

A male golden-crowned kinglet/Jim McCormac

Nature: Teeny-tiny golden-crowned kinglets are small, yes, but tough as nails

Columbus Dispatch
December 17, 2023

NATURE
Jim McCormac

What is the smallest songbird in Ohio? Ruby-throated hummingbird? Wrong, although it’s a trick question of sorts, as hummingbirds are not songbirds. They belong to the non-passerine birds, a large group that includes sandpipers, waterfowl, woodpeckers, hummingbirds and many other families.

The passerines, or perching birds, is the largest order of birds and includes familiar species such as cardinals, flycatchers, jays, and warblers. In all, the Passeriformes includes about 6,500 species — most of the birds currently known. And the tiniest of the lot in our region is the golden-crowned kinglet, an elfin that measures only four inches in length, sports a seven-inch wingspan and weighs but six grams. That’s barely more than a nickel. Quite a contrast to our largest regularly occurring native bird, the wild turkey. Big toms regularly eclipse 18 pounds, and the largest ever killed was a Kentucky gobbler that crushed the scales at 37.6 pounds. It would take 2,845 golden-crowned kinglets to equal the mass of that turkey.

Golden-crowned kinglets may be small but they’re tough. The core breeding range is a broad swath of boreal forest ranging from Newfoundland, Canada, to Alaska. Kinglets are heavily associated with conifers, and also breed at higher elevations of eastern and western mountain ranges. Ohio is on the southern edge of the nesting range, and there have been only a handful of breeding records, mostly in the northeast quarter of the state.

In winter, kinglets disperse south across the lower 48 states, and become common in Ohio. These sprites can be easily missed due to their size, and propensity for foraging in the heavy cover of coniferous trees. Those tuned into their frequently delivered wispy, high-pitched tsee-tsee-tsee calls will find far more kinglets.

I visited Green Lawn Cemetery on Dec. 7, camera in tow, seeking feathered quarry. The cemetery, on Columbus’s south side, covers 360 acres and is a haven for birds. My main target was a pair of merlins that have been hanging out there. The powerful little falcons mostly feed on songbirds and they’ve got plenty of prey at Green Lawn. I found both merlins, and many photos later wandered off in search of other subjects.

To my delight, I soon stumbled into a half-dozen golden-crowned kinglets foraging in a copse of ornamental cedar and spruce. An assemblage of kinglets is known as a court, and these birds were presiding in the lower boughs, luckily for me. I began firing away with my camera, but securing quality images of kinglets is no easy task. They are nearly always in motion, flicking wings and tail, and darting among the branches. I took around 400 images, and ended up with about 10 keepers.

Both males and females were present. The latter have but a golden stripe on the crown. Males, as in the accompanying photo, are adorned with flaming orange and gold stripes. When agitated or feeling assertive, a male will fluff the crown feathers into a riotous explosion of color, as if the top of its head went aflame.

While kinglets eat small amounts of seeds and fruit in winter, the overwhelming majority of their diet is small invertebrate prey. Mites, spiders, springtails, various insects, their eggs, etc. Many species in these groups are active or at least in accessible spots in winter, and kinglets are adept at finding them. A real kinglet treat is a caterpillar. Some conifer-specialist moth species’ caterpillars overwinter, plastered to twigs and blending with bark to an incredible degree. Kinglets find plenty, though.

Biologist Bernd Heinrich, in his remarkable book "Winter World," describes the mechanisms that enable kinglets to survive frosty winter nights when temperatures might plummet below zero. For starters, they maintain a body temperature of about 110 degrees Fahrenheit. Humans risk heat stroke and death once internal temperatures reach about 104 degrees. An inch-thick-layer of soft down feathers is covered by shingle-like contour feathers that trap body heat. In effect, the kinglet lives in a down-filled sleeping bag. At night, the bird stuffs it head into its feathers, shielding it from bitter cold. To further retain warmth on especially cold nights, small groups of kinglets huddle tightly together on inner branches overarched with snow-covered needles. Such arboreal snow caves further reduce heat loss by offering protection from wind.

The golden-crowned kinglet may be an impossibly tiny, feathered gem, fragile and delicate at first glance, but it’s tough as nails.

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.

When agitated, golden-crowned kinglets flare their brilliant crown feathers/Jim McCormac

Thursday, December 14, 2023

Pencilflower

 

I apologize for the paucity of posts of late. Generally, I try to slap about two subjects up weekly, but that's not been possible in the past few weeks. Hopefully I'll be able to get back in the groove soon enough. Anyway, to the task at hand.

I've probably always been more drawn to the obscure rather than the overt, and this plant fits that bill. It is Pencilflower (Stylosanthes biflora), a tiny pea family member. The yellowish flower is only about 7 mm in length, and the herbage of this nearly prostrate plant is also very diminutive. Pencil-flower favors dry barrens and openings, and easily succumbs to succession by larger plants. Southern Ohio represents its northern limits, and Pencil-flower has been documented in less than a dozen counties in the state, probably no longer occurs in all of them, and populations are often quite small and widely scattered. I shot this specimen in Shawnee State Forest, Scioto County, Ohio, on August 25, 2023.

Monday, December 4, 2023

Young white-crowned sparrows perfecting melody still a delight to behold

 

An adult white-crowned sparrow sings a perfect song/Jim McCormac

Young white-crowned sparrows perfecting melody still a delight to behold

December 3rd, 2023

NATURE
Jim McCormac

I am only a sparrow amongst a great flock of sparrows.

— Evita Peron

There are lots of sparrows. Excepting birders, they get little play or press. I was mildly self-disgusted to scroll back through the roster of nearly 400 Dispatch columns I’ve written to date and see that I’ve written about them only thrice. And now, a fourth time.

On a recent frosty morning, Ohio State University biology professor Shauna Weyrauch and I ventured to Slate Run Metro Park in northern Pickaway County. A highlight of the 1,700-plus acre park is a sprawling conservation area on the park’s western border. Numerous wetlands, meadows, thickets, and woodland patches create a diversity of habitat.

Birds were our targets and quarry was plentiful. A pair of giant sandhill cranes offered great looks. The big birds have nested here, and this may have been the local pair. Less conspicuous was five Wilson’s snipe that rocketed from a thick patch of smartweed. Yes, snipe actually exist beyond the campfire legends of “snipe hunting”.

I was pleased to hear the rough “jit-jit” notes of a ruby-crowned kinglet. While a common migrant earlier in fall, by late November the tiny bird is rare. Its tinier relative the golden-crowned kinglet was common, as was our hardiest warbler, the yellow-rumped warbler. Several purple finches, down from the North Country, were also present.

But it was sparrows that consumed much of our attention. We detected eight species, and missed another, the field sparrow, that was surely present. Although the temperature was only in the high 20s, sunny conditions stimulated much singing among the sparrows. A fox sparrow gave its slurred drunken whistles, somehow melded artfully into a pleasing aria. Well-named song sparrows delivered their complex tunes, and white-throated sparrows whistled from thickets.

We were especially pleased to come across a band of white-crowned sparrows. This species nests far to our north, in taiga and tundra habitats. Adults sport crisply striped heads — think Michigan Wolverines football helmet, but with the stripes black and white. Duller first-year birds were also present, and the bird in the photo was one of them. It was born last summer, and it’ll take the better part of a year to develop the natty headgear.

Although white-crowned sparrows are not particularly shy, they were mostly busy seeking seeds in thick cover. Their airy buzzy songs gave them away, and thus guided to their honey holes, we were occasionally rewarded with views when one teed up on a plant.

White-crowned sparrow song is a delight to the ear: a mellifluous series of whistles and buzzes infused with a rather melancholy tone. While some adults sang and did so perfectly, the as-yet unpolished juveniles were more conspicuous to my ear, in the way that an un-tuned guitar would be. Young white-crowns begin their singing lessons within a few months of hatching, but mastering the melody takes much practice.

Young white-crowned sparrows must learn their songs from adults, and lesson one begins almost immediately upon fledgling. They imprint the song of nearby males, creating a mental model that they will later learn to duplicate. Then comes the plastic (adaptive learning) phase, in which young sparrows practice their songs to be. This formative period lasts throughout winter and into spring, and it was this raw product that we heard much of on our Slate Run expedition. The youngsters sound unpolished, akin to a kid early on in his or her musical lessons on a recorder. There are imperfections in notes, sequence and overall delivery.

By the time these as yet amateur avian musicians reach their northerly breeding grounds late next spring, they’ll be able to sing like Pavarotti. Practice makes perfect, even in the bird world. And when it comes to sheer aural elegance, few of our birds can match the sparrows.

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.

A subadult white-crowned sparrow practices singing/Jim McCormac

Tuesday, November 28, 2023

Invasive honeysuckles and birds

 

A western Ohio woodland, its understory utterly dominated by Amur Honeysuckle (Lonicera maackii). While there are other species of Asiatic honeysuckles running amok in the Midwest, this one is by far the worst culprit in most areas I visit. It is firmly entrenched in our flora, much to the detriment of the indigenous plants.

As always, click the image to enlarge

It wasn't always so. The nonnative bush honeysuckles like Amur Honeysuckle weren't a major problem until fairly recently. In Lucy Braun's The Woody Plants of Ohio (1961), she devotes a scant two sentences to it. Braun knew it only in the wild from the far southwestern corner of Ohio (Hamilton County) but did note that it was "becoming abundant".

This map is from Tom Cooperrider's decidedly unsexily titled The Dicotyledoneae of Ohio: Part 2: Linaceae through Campanulaceae. The book was published in 1995 and gives a snapshot of the progress of Amur Honeysuckle in Ohio. Twenty counties have been added since Braun's publication 34 years prior. It should be noted that botanical works such as these rely on vouchered specimens as evidence, and there are relatively few botanists that collect and archive material in herbaria. By 1995, Amur Honeysuckle was undoubtedly in counties beyond those depicted on this map but was definitely not the scourge it is now.

Cut to today, and documentation of the horror show that Amur Honeysuckle has become. The orange squares representing reports congeal into blobs, so frequent are the observations. This is part of the iNaturalist map, which relies on peer-reviewed photos submitted by observers. Ohio is smack in the middle of this snippet of the map, and honeysuckle pretty well blankets the state. Good old Lonicera maackii is certainly in all 88 counties, and at least locally abundant in many or most of them.

How did it get here? Apparently, the original escapes came from the New York Botanical Garden, which began promoting Amur Honeysuckle as an ornamental in 1898. By the 1930's and '40's, wildlife agencies greatly exacerbated the problem-to-be by widely promoting honeysuckle as a ground cover, soil stabilizer, and wildlife food plant. As often seems to happen with invasives, there was a few decades long gestation period where the plant did not run amok, but probably largely stayed where it was put. In Ohio and this region of the Midwest, the spread probably began in earnest in the 1980's and the trajectory was obvious by the time of Cooperider's 1995 book. One need only glance at the iNaturalist map to see what has happened since.

Small wonder people were smitten with Amur Honeysuckle. It is pleasing in form, and sports abundant showy white flowers.

Alas, those flowers later become equally showy fruit, also abundant. Brightly colored berries probably evolved to lure agents of dispersal, especially birds. Birds are drawn to bright fruit, and it is to the honeysuckle's advantage to have its berries eaten by highly mobile winged creatures. A frugivorous (fruit-eating) bird might expel the seeds a long distance away, effectively playing the unwitting role of avian Johnny Appleseeds. Birds are surely the primary reason for the remarkably rapid invasion across a broad swath of eastern North America.

An American Robin (Turdus migratorius) sits among a sea of Amur Honeysuckle fruit. It is akin to a kid in a bowl of M & M's. The 50-acre preserve where I made this shot is in Columbus, and I visited last Sunday. The site was thoroughly infested with honeysuckle, and dozens if not hundreds of robins gorged themselves on the fruit.

A first-year White-throated Sparrow (Zonotrichia albicollis) caught in the act, berry in beak. This species is probably our most abundant migratory sparrow, and many were present here - same site as the robin above.

With abundant frugivores such as the American Robin and White-throated Sparrow (not a major frugivore but nonetheless they have a taste for honeysuckle berries) eating this stuff, it's small wonder that honeysuckle has spread so rapidly and continues to do so. Many other bird species eat it as well including a hyper-abundant nonnative, the European Starling (Sturnis vulgaris). What is curious to me is the apparent lag time from when Amur Honeysuckle began to be planted commonly (1930's-40's), to when it became an obvious and worsening invasive plant (1980's). I wonder if birds, confronted rather abruptly with a completely foreign plant, basically ignore it for a while, not recognizing a potential food source. Maybe it takes a few decades for the feathered crowd to develop a taste for the stuff and begin ravishing it in earnest. But once they do, the game is over.

Amur Honeysuckle is so thoroughly entrenched now that there is no way to eliminate the overwhelming majority of it. Localized control in targeted parks and natural areas can be successful but constant vigilance is necessary as new seed sources will be introduced annually.

We can hope that Amur Honeysuckle eventually runs its course, and fades out, as some invasive species seem to do. But there's no sign of that happening yet.

Monday, November 20, 2023

Nature: Investigating the northern saw-whet owl in Ohio

A northern saw-whet owl rests in the hand of Blake Mathys, just prior to its release/Jim McCormac

Nature: Investigating the northern saw-whet owl in Ohio

November 19th, 2023

NATURE
Jim McCormac

Lots of interesting and little-known creatures emerge under cover of darkness. Some of them are human, but most are not. Perhaps foremost in piquing human interest about animals that ply their trade after nightfall are the owls.

Owls have long been a source of fascination to us. Athena, the mythical Greek Goddess of Wisdom, was smitten with owls and held them in high regard. A genus of owls, Athene, is named for her. It includes the North American burrowing owl, Athene cunicularia. In 1994, ancient art was discovered adorning the walls of Chauvet Cave in France. Some of this work depicts owls, and was created over 30,000 years ago. Effigy pipes depicting barred owls – a common Ohio species – created by Hopewell Indians date to around 100 B.C. and have been found in Tremper Mound in southern Ohio.

A local owl aficionado is Blake Mathys, a biology professor at Ohio Dominican University. He established the Central Ohio Owl Project (COOP) in the fall of 2020. I wrote about COOP and its goals in a February 7, 2021 column. One of his major study targets is one of our most charismatic little hooters, the northern saw-whet owl.

Mathys, who lives in Union County, bands saw-whet owls on his property each fall. A string of mist nets is placed in a wooded opening, and saw-whet calls are broadcast from a nearby speaker. Owls investigating the calls fly into the nets and become entangled. The soft mesh causes no harm, and captured birds are quickly extracted.

Netted owls are taken to the “lab,” a nearby table where each bird is measured, weighed and feather details are studied to determine age. The latter process involves shining ultraviolet light on the owl’s underwings. Newer feathers are infused with a compound known as porphyrin, which glows fluorescent pink under UV light. With experience, the bander can accurately assess the bird’s age by its pinkness or lack thereof.

Perhaps most importantly, a lightweight aluminum band is placed on a leg. The band sports a unique number and allows positive identification if the bird is recaptured. An enormous amount of information regarding bird migration, seasonal movements and longevity has been amassed by banding. In the case of northern saw-whet owls, most of what we know is the result of efforts by banders such as Mathys.

I was fortunate to be part of an assemblage that visited Mathys’ banding operation on the night of November 11. A nip was in the air as darkness fell, and it was downright chilly when we made the first net check. Nothing. Brief disappointment ensued but that was offset by optimism for upcoming net runs. Sure enough, we were elated to see two saw-whet owls in the nets on the second check.

Both birds turned out to be hatch-year females. They would have been born in spring or early summer, and probably WAY north of where they were caught. The vast majority of saw-whet owls breed in northern forests across Canada and the northern states, from Alaska to New England. There are only two recent Ohio nesting records, from Erie and Huron counties along Lake Erie. At one time, the owl was a more frequent nester in northern Ohio.

Most of the people present this night had never seen one of the wee owls and were thoroughly enchanted. A big one – females are larger – weighs around 100 grams, or the same as 15 quarters. They measure but 8 inches in length, with a wingspan of a foot and half. In contrast, our largest owl is the great horned owl, and it tapes out at nearly 2 feet in length with a 4-foot wingspan and body weight of 3 pounds.

Northern saw-whet owls are incredible nocturnal hunting machines. Their eyes constitute nearly 5% of the body mass and have many more cones than human eyes. This allows them to see in darkness with amazing accuracy. Large offset ears permit fine-tuned sound triangulation. Woe to the scurrying rodent, even if it’s under vegetation. Flight feathers edged with comb-like extensions allow for silent flight, and once a pounce is made, the owl seizes its victim with powerful talons from which escape is impossible. I would note that the first thing someone usually says upon clapping eyes on a saw-whet owl is “cute”. Many mice and voles would strongly disagree.

Blake Mathys has captured nine saw-whets this fall, and more will undoubtedly follow. Last fall he caught a remarkable 34 birds. Kelly Williams, a bander working with Tom Bartlett on Kelleys Island, caught 16 owls on the same night we were out. Bartlett has captured over one thousand in his decades of banding on the Lake Erie Island, demonstrating that the owls migrate across the great lake.

The work of Mathys, Bartlett, Williams, Bob Placier (who bands saw-whets in Vinton County) and others have illuminated the frequency of this owl. During migratory periods, and probably in winter, the little owl is probably the most common owl of the seven (eight, if snowy owls are present) species in Ohio.

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. 

Monday, November 13, 2023

Eastern Screech-Owl in dark woods

 

A gray morph (not "phase" as color forms are incorrectly often referred to as) Eastern Screech-Owl stares from its perch in an inky woods. Owl eyes, in comparison to human eyes, are proportionately enormous and in some species - including the next owl species that I'll post about - can make up 5% of the total mass of the owl. Owl eyes also have many more rods per cone, thus their eyes are far more efficient at detecting movement in dark conditions. The net result is eyes that are dozens of times better at harvesting light than human eyes.

Shauna Weyrauch, I and about 25 others had a great evening owling last Saturday night with Blake Mathys, an owl expert and bander in west-central Ohio. We observed or heard three owl species, including the one above, and another species which is quite special, and I'll write more on that one later.

PHOTO NOTE: With highly nocturnal creatures such as owls and bats, it's better NOT to pop a bright flash in their faces. But light is certainly required, as even at the highest ISO setting and widest aperture it won't be possible to harvest adequate light for an exposure in extremely dark conditions. Blake spotted this owl - one of a pair that he knows well - with infrared glasses, and then we used a flashlight beam to illuminate the bird so that all could admire it. My experience with lighting screech-owls in this way is that it seems to bother the low-key birds little, and certainly doesn't have the blinding effect that the brilliant and sudden pop of light from a flash would have.

I have a cool device known as a Neewer CN-160 dimmable light panel. It mounts on the hotshoe of my camera and provides an adjustable and constant light source. I can put just enough light towards the subject to find focus and illuminate it enough for photos. To avoid turning the Neewer up to blinding light levels, I use a higher ISO (much as I dislike having to use high ISO settings, but there is a time and place for them). The settings for this image were ISO 6400, f/8, and 1/200 shutter speed. As we weren't especially close to the owl - maybe 20-25 feet - and I used a 100mm macro lens (on the camera for the primary subject of that evening), I also had to crop a fair bit. So, the graininess associated with a higher ISO is manifesting a bit, but it is still a usable image. And the owl was still there when we departed, no worse for the wear.

Monday, November 6, 2023

Nature: Ohio's Metzger Preserve harbors strange yet impressive rock formations

Metzger Preserve harbors one of the state's greatest concentrations of the bizarre, round rock formations known as concretions/Jim McCormac

Nature: Ohio's Metzger Preserve harbors strange yet impressive rock formations

Columbus Dispatch
November 5, 2023

NATURE
Jim McCormac

The Pekowi were a band of the Shawnee tribe, one of five divisions of the once-great confederacy. The county just south of Franklin County derives its name from the Pekowi: Pickaway. Until nearly 1800, the Shawnee and other Native Americans reigned over the wildlands of the Ohio country. An especially famous Shawnee was Tecumseh, who was born circa 1768 near Chillicothe.

At the time of Tecumseh’s birth, what would become Pickaway County was densely forested, the woodlands broken by a roughly 5-by-7-mile tract of prairie that bordered the Scioto River between present day Circleville and Chillicothe. It is known as the Pickaway Plains, but the prairie’s destruction is almost absolute. Less than a fraction of a percent remains.

In the early 1770’s, a Christian missionary named David Jones ambled into the Pickaway Plains region, seeking converts. Such missionaries were often harbingers of doom for the indigenous peoples, and soon an avalanche of settlers followed. The bounty of timber was irresistible to the immigrants, and the first lumber mill, near present-day Williamsport, began service in 1812. More soon followed. Before long, the forest primeval had been largely cleared.

An inventor named John Deere, who had fled his home state of Vermont to Illinois to dodge bankruptcy charges, wasted no time in his adopted state. In 1837, one year after his arrival, Deere launched his self-scouring steel plow which would forever alter the former forests and prairies of the Midwest and its nearly incalculable biodiversity.

By the dawn of the 20th century, most of Pickaway County had been converted from forests, prairies, pothole wetlands and fens harboring a thousand native plants to monocultures of corn, soybeans and wheat. Only scattered shards of former habitats remain.

In 2002, the Pickaway County Park District was created. For its first 15 years, the district operated on a shoestring budget, but in 2017 a levy to provide permanent funding for the park district was put before Pickaway County voters. They passed it with 55% of the vote. The district has not let the grass grow under its feet since, and is hard at work protecting Pickaway County natural gems.

Pickaway County Parks purchased the 52-acre Metzger Preserve along Deer Creek in 2019. Deer Creek is one of central Ohio’s finest streams, and this acquisition helps protect its water quality and rare fishes. But the preserve also offers the public a window into a geological history that is far older than the region’s human history.

On Oct. 28, I visited Metzger with Shauna Weyrauch, an Ohio State University professor and bobcat researcher. We weren’t looking for wildcats — they would have been common in Tecumseh’s time — but for a more easily found subject: rocks.

Metzger Preserve harbors one of the state’s greatest concentrations of concretions: bizarre round rock formations that look like oversized bowling balls. Concretions were formed by a buildup of minerals congealing around a nucleus such as a fossil, bone fragment or crystal. Metzger’s concretions are composed of siderite, an iron carbonate. The stony oddities date to the Devonian, a period of the Paleozoic Era that began 419 million years ago and lasted for 60 million years. So strange is their appearance that concretions were once thought by some to be dinosaur eggs, or flotsam left by extraterrestrials.

The concretions at Metzger Preserve are embedded in a deposit of Ohio Shale. Deer Creek has cut into this shale bank over the ages, eroding away the softer shale and liberating numerous concretions. The result is a fantastic, almost surreal streambed littered with what looks like castoff cannonballs. From afar, the rounded tops of the concretions resemble scores of turtle shells jutting from the water. Big specimens can be 8 feet in diameter.

If you visit Metzger, be sure to go when Deer Creek’s water levels are low and the concretions are easily visible. Another recommended stop nearby is Calamus Swamp, one of very few glacial kettle lakes remaining in the region. It is owned by Columbus Audubon and features a boardwalk that traverses the 19-acre wetland.

For more information on Metzger Preserve and Calamus Swamp, visit: columbusaudubon.org and pickawaycountyparks.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 atwww.jimmccormac.blogspot.com.

Thursday, November 2, 2023

Cardinal-flower, and the coming floral hiatus

A brilliantly hued Cardinal-flower (Lobelia cardinalis), shot back on August 25, 2023. A floral hiatus now ensues, until the blooming of Skunk-cabbage at winter's end, at least in my part of the world. It got down to 29F last night, here in Worthington, Ohio. This Cardinal-flower was photographed in Scioto County, Ohio.

Photographic Note: Reds in flowers can be tricky to expose properly (as can yellow). It's easy to overexpose them, and thus wash out the gorgeous hues that make red flowers so fetching. Depending on the conditions, I often underexpose a bit, maybe 1/3rd stop, sometimes more. Wind is also not the flower photographer's friend, and as I recall this was a mostly windless day. Thus, I shot from a tripod with a 2-second timer delay (so I am not touching and possible moving the camera at the time of exposure). I also have the camera (Canon R5) set to touch screen focus. I just touch the spot that I want to have as the focus point on the camera's back screen, and Voila! Two seconds later the camera fires, focused on the exact spot that I touched. I'm also partial to very open apertures when I feel that I can get away with them, as f/4 (in this case) creates such a beautifully blurred background (bokeh). f/4 to f/7.1 are favored flower apertures although I will frequently venture off that reservation. ISO, of course, is set very low - 200 in this case. For floral photography, shutter speed is largely irrelevant to me, especially if there is not movement on the subject's part. This image was shot at 1/25 but I have often shot flowers at speeds as low as several seconds.
 

Sunday, October 29, 2023

Nature: "Tis the season to spot dark-eyed juncos in central Ohio

 

A male dark-eyed junco snacks on poison ivy berries/Jim McCormac

Nature: "Tis the season to spot dark-eyed juncos in central Ohio

Columbus Dispatch
October 29, 2023

NATURE
Jim McCormac

“…there is not an individual in the Union who does not know the little Snow-bird…”
− John James Audubon (1831)

I suspect the great naturalist and pioneer ornithologist was optimistic in his estimation of junco familiarity. His “snow-bird” is now formally known as the dark-eyed junco, and back in Audubon’s time, people were far more attuned to the environment. Many if not most people probably were acquainted with the jaunty slate-colored sparrows.

Even today, with the popularity of bird feeding, lots of people know the junco. But in central Ohio, they’re primarily winter visitors. Juncos arrive on the first gusts of nippy fall winds from northern breeding grounds. I ran into my first dark-eyed juncos of fall just a few days ago, as nighttime temperatures began to dip towards the freezing mark.

Unlike many of its sparrow brethren, which are skulkers and shrinking violets, dark-eyed juncos are extroverted and easily observed. Adult males are a rich dark slate color above, with snowy underbelly and a pink bill. Their white tail feathers are often flashed conspicuously. Females and juveniles are more muted and infused with brownish hues.

There are plenty of dark-eyed juncos to see. The population, which breeds strictly in the U.S. and Canada, numbers about 630 million individuals, or about two juncos for every person. While juncos nest throughout the boreal forest of the northern U.S. and Canada, birds in northerly populations retreat southward in winter. These are the birds that we see at our feeders.

Ohio lies at the southern limits of the junco’s breeding range, with isolated nesters in the extreme northeast, especially Geauga and Lake counties. A small population breeds in Mohican state forest. But if you receive juncos at your feeders, the likelihood is that they hail from remote northern forests.

Over its vast North American range, the dark-eyed junco varies markedly in appearance. So much so that until 1973 it was divided into five species: gray-headed junco, Guadalupe junco, Oregon junco, slate-colored junco (our birds), and white-winged junco. Typical examples of each form are easily identified, but they all hybridize and produce fertile offspring, which is why the five were lumped into one species. The Oregon subspecies appears rarely but regularly in Ohio. Adults are recognizable by a black hood that contrasts with pinkish-brown flanks.

If you feed birds, you’ll almost certainly attract juncos. The jaunty little sparrows usually feed on the ground, often flashing their bright white tail feathers. Many species of birds that are habitual ground-foragers have white outer tail feathers. One explanation is that it presents a false flag to bird-hunting raptors like Cooper’s and sharp-shinned hawks. The raptor fixates on the junco’s bright tail feathers, seizes those, and the junco escapes, sans tail. But tail feathers grow back, and the junco lives to see another day.

The roughest of winter weather does not deter tough juncos. They essentially live in a sleeping bag of feathers, the dense down feathers shingled over by sturdy waterproof contour feathers. Juncos can stave off the coldest of Ohio temperatures. If snow covers food sources, they kick through it like little chickens to uncover the seeds.

Come mid-March, dark-eyed juncos start their northward journey. By May, nearly all of them have moved north, leaving us with to deal with a five-month junco hiatus. Throw some seed out for the snowbirds, and enjoy them will you can.

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.

A female dark-eyed junco, or snowbird/Jim McCormac

Monday, October 23, 2023

Fall colors

The autumnal plumage of Sugar Maples (Acer saccharum), especially, enliven a backwoods Adams County lane. One of the great delights of living in the eastern deciduous forest region is the annual coloring of tree foliage. Ohio is a particularly good place to bear witness to this phenomenon, and especially so in the hill country of southern Ohio, where I made this shot yesterday.

Fall colors were not yet peak, and if high winds don't remove most of the leaves between now and then, I would say that next weekend should be prime time to observe fall leaf color, at least in central and southern Ohio.

Thursday, October 19, 2023

Moth Talk: October 24, Columbus, Ohio. All are welcome!

I'm giving a talk on the amazing world of moths for Columbus Audubon at the Grange Insurance Audubon Center, hard on the banks of the Scioto River near downtown Columbus (Ohio), on Tuesday, October 24. Doors open at 6:30 pm, and the show gets on the road around 7 pm. It's free, and all are welcome. Just show up if you want to come.

This talk is loosely based on the new(ish) book Gardening for Moths, by Chelsea Gottfried and me. That book (hit the shelves in late March 2023) features a robust introduction that makes the case as to why moths are important. And that's mostly what I will do with this talk: build the case for the importance of moths and how they interplay with bats, birds, other animals, our native flora, and more. Our (mostly) nocturnal butterflies are fascinating on many levels, and do not get nearly the attention that they deserve.

This LINK has all of the details that you need. Would love to see you there!
 

Tuesday, October 17, 2023

Rough green snake spotted in southern Ohio

A rough green snake lurks in a wild lettuce plant/Jim McCormac

Rough green snake spotted in southern Ohio

October 15, 2023

NATURE
Jim McCormac

Behold, I have given you authority to tread on serpents and scorpions, and over all the power of the enemy, and nothing will injure you. − Luke 10:19

While 26 snake species slither about in the Buckeye State, they are largely out of sight and mind. That’s probably a good thing to many people, as ophidiophobia (human fear of snakes) is quite common. More importantly, it’s far better for the snakes that relatively few people clap eyes on them. Humans are, by far, a snake’s worst enemy.

Bad PR for serpents began at least as far back as the Bible, which is rich in anti-snake passages. Snakes are clearly used as a metaphor for evil, which is entirely underserved. The popularity of that ancient tome has colored people’s perceptions of one of our most interesting animal groups for millennia.

We directly persecute snakes, for no good cause. In Ohio, the overwhelming majority of our reptilian wrath is directed at non-venomous species, which constitute 23 of our 26 species. Common victims of humanoid malice are species like the eastern gartersnake and gray ratsnake.

Both species are utterly harmless. Even the three venomous species in Ohio are generally quite mellow. I’ve encountered the eastern copperhead, Massasauga (rattlesnake) and timber rattlesnake numerous times over the years, and in all cases their docility was notable.

One must work to run afoul of a snake. Far easier to leave them be, which is just how they would have it.

To me and many of my comrades, encountering snakes of any species is always a highlight of an outing. But a northern rough green snake (Opheodrys aestivus)? Rare indeed will be the animal that will one-up that experience.

Back on Sept. 8, I and 15 or so others were ambling along an old road through Shawnee State Forest in southern Ohio. We were attending a native plant conference, and this was a nocturnal field trip to seek creatures of the night. Suddenly out of the dark came a shout. Denise Arnett Ruby had discovered a green snake!

Everyone rushed over to ogle the handsome serpent. Rough green snakes are diurnal, spending their days slinking through low branches of trees and shrubs seeking caterpillars, crickets, spiders and other invertebrate fare. When threatened, the lime-green snake freezes and becomes nearly impossible to see amongst the foliage.

Green snakes sleep at night and are often easier to find under a flashlight beam. That’s how Denise spotted this one, and we were all beneficiaries. It was a “life snake” for nearly the entire group.

All 26 species of Ohio’s snakes have declined since the arrival of settlers, many of them alarmingly so. The rough green snake has probably decreased more than most. It is a southerner at the northern limits of its range in southern Ohio. Historically, it was documented in 14 counties. Now, it is only known to be in five.

Direct human persecution probably isn’t a major factor in this case. Highly arboreal green snakes are just too secretive and hard to spot and tend to occur in sparsely populated areas. They favor woodland edges and forest openings, and that’s the habitat I’ve seen all of the 15-20 individuals I’ve encountered over the years.

Forestry management practices, particularly logging, has undoubtedly decreased their numbers. In addition to degradation of the green snake’s woodland habitat, logging operations can destroy or damage nest sites: hollow logs, tree cavities, deep leaf litter, rocks etc. Outright development of forested habitat, or conversion of woods to agriculture or other open habitats, is likely even a bigger factor in the snake’s decline.

Our green snake was a bit perturbed at being roused from its slumber, and wriggled about for a bit. It eventually settled in and allowed the group to closely inspect it and get photos. The snake made no effort to bite, and such an attempt would be rare indeed. I’ve handled a number of them and not one has tried to strike.

Conservation of large, wooded ecosystems such as the 70,000-acre Shawnee State Forest is essential to protecting sylvan creatures such as the rough green snake. That also applies to wise forest management, which should include conservation of all native biodiversity.

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.jimmccormac.blogspot.com.

Wednesday, October 11, 2023

A fine toad

 

Our group ran across this whopper of an American Toad (Anaxyrus americanus) while on a nocturnal field trip in Shawnee State Forest (Scioto County, Ohio) on September 10, 2023. I could not resist making images of the big amphibian, and the toad cooperated nicely as they often do. Of course, I toad her not to move and fortunately she toad the line nicely. I've got scads of toad imagery, but can seldom resist new portraits, especially when the model is as fine as this one was.

I do appreciate the articulating back screen of my camera (Canon R5), which allowed me to set the camera on the ground for the shot and still see the composition by merely folding the screen out and looking down at that. To further ease the task, I have the touch screen set so that when I touch a spot on the screen, the camera automatically focuses on that spot then takes the image. This is all getting almost too easy.

I've spent my fair share of time in pre-articulating screen days prostrate on hard rocky substrates to get on my subjects' level, and that ain't much fun. I have zero qualms about going prostrate for photos and do so all the time. In fact, it's one of my favorite positions for photographing wee beasts, as it's important to be on your subject's level. But going flat on those hard rocky roads with big pebbles jabbing you? No thanks and I'm grateful for camera technology that sometimes makes that unnecessary.


Thursday, October 5, 2023

American Bolas Spider

Back on September 14, I visited an interesting property in rural Pike County, Ohio (well, I guess nearly ALL of Pike County is rural) to assist with a one-year bioblitz project spearheaded by John Howard. I'd been trying to get there all summer, but this is the year of talks for me, thanks to the new Gardening for Moths book, and the speaking gigs have thrown wrenches in many plans (but I'm not complaining).

John and the scores of experts he's had to the property have found a mountain of species, and I'll hope to report on that after the project has concluded. John, Stefanie Paeg and I roamed the property most of the day and managed to extricate some new species for the list - mostly insects and plants. Later, spider expert Rich Bradley joined us, as did Laura Hughes and Vince Howard. Towards day's end, photographer Sam James finally caught up with us way out on the trail, and shared news of a great find that he made soon after heading out on foot.

This is Sam's find, as it appears from 15 feet away. As you've probably guessed, it's the little white blob amongst all of the Black Willow (Salix nigra) foliage.

We move in closer, and voila! The apparent bird dropping reveals itself to be an American Bolas Spider (Mastophora hutchinsoni). Bolas spiders are always notable finds, and generally everyone, at least in my circle of friends, wants to see them. During the day, the females, which are much larger and more conspicuous than males, hide in plain sight atop leaves. From almost any distance they resemble fresh bird droppings and thus presumably escape the attention of would-be predators. The bulbous waxy-white body, intermixed with brownish tones, looks remarkably similar to bird scat.

Staring straight into the grill of the spider, we see her legs neatly tucked around her head. This one appears to have spun a pad of silk which she's sitting atop. I do not know what that's about, but perhaps to help hold her in place if the wind starts buffeting her perch. She'll remain like this all day, so we made sure to re-visit her after nightfall.

When we returned, she had already caught a moth, even though it was barely past dusk. Her Lepidopteran victim, enshrouded in silk, hangs behind her. Bolas spiders, at least from my limited experience, do not make much of a web. Basically, they weave a flimsy trellis of silk lines from which they hang and hunt from. Given their highly specialized moth-hunting skills, a fancy web is not necessary.

We stopped back a while later, and the bolas spider had just captured another moth. She's fangs deep in the freshly captured victim in this shot.

Bolas spiders in the genus Mastophora - there are about 50 species - occur only in the Americas. They specialize on moths and use some amazing tactics to capture them. The female spider emits pseudo-pheromones from its body that mirror those emitted by certain female moth species. The males of those species detect those airborne false flags, and thinking a female of their species is nearby, flutter ever closer. When the moth comes into range, the bolas spider flicks a strong silken strand tipped with a sticky globule at it. If her aim is true, the moth is snared, reeled in, killed, and eaten. In times of plenty, as apparently was the case this night, she will cache victims as in the previous photo.

I never saw her line, or bolas, on this night, but presumably she used one to capture these moths. For a good image of a bolas spider's bolas, CLICK HERE for the story of an encounter with a Toadlike Bolas Spider, (M. phrynosoma).