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

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.

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.

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.

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

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.

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

Columbus Dispatch

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