Nature: Some birds built to withstand frigid weather

A horned lark seeks seeds/Jim McCormac

Columbus Dispatch

January 7, 2018

NATURE
Jim McCormac

The exceptionally frigid weather of late reminds me, as it always does, how tough the feathered crowd is. When the mercury plummets to zero or below, one wonders how birds survive. It’s 1 degree Fahrenheit outside as I write this, and I’d surely not want to overnight out there.

But not only do birds survive Arctic chills, most of them thrive. At least those that linger.

Far fewer species occur in Ohio in winter than any other season. Most birds migrate to warmer, more food-rich climes. Some may only venture a few states southward; others might go all the way to the tropics. They’ll return when days lengthen and food supplies increase.

Half-hardy species can be “fair-weather” migrants, such as blackbirds, turkey vultures and eastern bluebirds. If winter conditions turn brutal, many of them flee south. They may remain in mild winters.

Waterbirds such as ducks, herons and gulls have little choice but to bail out when water turns to ice, as it is now. Still, if any open pockets remain, such as below dams, there will be lingerers. It’s bone-chilling to watch a mallard or ring-billed gull cavorting in freezing water in single-digit temps, acting as if it’s on a Florida beach.

Birds have a physiological mechanism that helps them cope with cold: a specialized circulatory system called the rete mirabile, a Latin term meaning “wonderful net.” Dense meshlike arteries and veins in the feet and legs efficiently circulate warm blood, thus preventing freezing.

Birds’ feathers are magical insulators. Imagine wearing a heated sleeping bag. A dense layer of down feathers traps and retains body heat. Overlapping the down, like shingles, are various contour feathers. These further prevent heat loss, shield against icy gusts and repel water.

Behavior helps, too. Birds will often alternate tucking their legs into dense feathers when at rest, an effective warming tactic. They’ll fluff their down to elephantine proportions, becoming fat, toasty butterballs.

Of course, food is the fuel that stokes avian fires and gives them the energy to combat frigid winter weather. American robins, European starlings and cedar waxwings form nomadic flocks, moving between fruit trees. Seed-eaters often become more plentiful at backyard feeders during cold snaps. Blue jays, nuthatches and red-headed woodpeckers tap into caches of seeds they hid in the fall. Open pockets of water can be packed with gulls and ducks seeking fish and aquatic plants.

Perhaps the most amazing of our wintering songbirds is the golden-crowned kinglet. One of these Lilliputs is just 4 inches long and weighs the same as a quarter. An Ohio winter is their tropical vacation. Most kinglets breed in the broad swath of coniferous forest spanning Canada and the northern United States.

Remarkably, kinglets are almost entirely insectivorous. They are adept at locating insects and their larvae, especially caterpillars. Yes, caterpillars. A number of species of inchworms overwinter on branches, freezing solid, and emerging from their cryogenic state when temperatures warm. Many fall prey to sharp-eyed kinglets.

To help survive long, cold winter nights, kinglets sometimes huddle together under snow-capped conifer needles, creating their own microclimate.

Perhaps toughest of all songbirds is the horned lark. These birds frequent wide-open agricultural wastelands, where they forage for seeds. Howling winds, polar temperatures and snow cover do not deter them. Come nightfall and plunging mercury, larks huddle in earthen divots, or even become covered with snow, which helps insulate them.

Cold as you may be watching them, don’t worry much about the birds. They’ve been dealing with frosty winters far longer than we have.

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 tiny golden-crowned kinglet foraging in single-digit temperatures/Jim McCormac

Some Florida waders + cute owls

The polar blast continues here in Columbus, Ohio and elsewhere in the Midwest. It's 10 F as I write this, and will drop below zero tomorrow night. It's been frigid for a while - a true winter! - although it is projected to warm significantly next week.

I've been working through photos from a Florida trip of last February - paring the wheat from the chaff, labeling, and archiving. Just looking at all of these Floridian birds makes me feel warmer, and the images bring back memories of basking in balmy Sunshine State weather, often only arm's length from excellent subjects. If you like to photograph birds, it's hard to beat Florida.

All of these, with the exception of the burrowing owls, were shot at either Ding Darling on Sanibel Island, or Gatorland near Orlando. The owls were some of the many that call Cape Coral home.

The drive through Ding Darling produces LOTS of birds, and lots of photo ops. Here, from L to R, is a white ibis, snowy egret, and great egret - studies in elegant whites.

A snowy egret, yellow slippers on display, drops in for a landing.

 Gotta love the wild head of plumes on a snowy egret. I came back from this trip with many thousands of images, thanks to numerous encounters with photogenic beasts such as this.

 A tricolored heron rages through the shallows. This is a hyperactive hunter, chasing prey, flapping wings wildly, and in general acting spastic. Quite a contrast to the much more sedate, studied tactics of a great blue heron.

A goggle-eyed juvenile yellow-crowned night-heron lurks at the edge of some mangroves. It, as should be surmised from the name and huge eyes, does most of its hunting after dark.

As always, click the photo to enlarge. And in this case, admire the amazing cerulean-blue eye of this white ibis.

Two of the many burrowing owls that make Cape Coral home stand sentinel at the entrance to their burrow. This city - either the largest or second-largest of any in Florida by acreage! - harbors a large population of these subterranean nesters, and I've written more about them RIGHT HERE.

Stay warm!

Nature: Ohio scientists finally learning flying squirrels' secrets

A southern flying squirrel in Athens County/Jim McCormac

Columbus Dispatch

December 31, 2017

NATURE

Jim McCormac

Perhaps no one knows as much about southern flying squirrels as Don Althoff. The professor of biology at Rio Grande College in southern Ohio has devoted two decades of study to these fascinating mammals.

I spent one early-December day shadowing Althoff as he conducted squirrel research in the rugged, forested hills of rural Athens County. We weren’t alone. The squirrels intrigue many of his students, and at least 15 of them joined us.

While largely out of sight and mind, flying squirrels are often the most common of our squirrels, at least in wooded habitats. They frequently occur in well-treed urban neighborhoods, including many in Columbus and its suburbs.

But southern flying squirrels are strictly nocturnal. Sometimes they’ll visit bird feeders, and if the feeders are lit by nightlights, people may notice them. Sometimes slathering peanut butter on tree trunks lures them in — Jif is irresistible to the elfin fliers.

A flying squirrel is much smaller than the more familiar, daytime-active gray and fox squirrels, which outweigh them by factors of 9 and 11, respectively. When seen in the flesh, a flying squirrel appears impossibly tiny: a lemur-eyed woodland sprite appended with a miniature beaver tail.

The indefatigable Dr. Althoff goes to great lengths to connect with his subjects. He has hung dozens of wooden nest boxes at five southeastern Ohio sites, all of which are far from the beaten path. Each box is about 12 feet aloft, tacked to a tree trunk.

Working a “squirrel trail” means lugging a large ladder and various research gear through dense woods and up and down steep slopes.

During the day, the squirrels hole up in cavities and readily adopt artificial boxes. Our expedition inspected 25 of them, and four boxes contained a total of 19 squirrels. The wee beasts are highly social and prone to sharing cavities. Althoff’s record is 13 in one box.

Between the mammals’ shared body heat and the insulating effect of plant material they place in the cavity, the inner box temperature remains quite toasty — an advantage on frigid winter days.

When researchers arrive at a box, they prop a ladder into place and go up. They quickly plug the entrance hole and bring down the box. An Althoff-engineered tube system safely funnels the squirrels from the box, and each is inspected, its weight and sex recorded. Each also gets a small ear tag for future identification and is photographed and released.

A squirrel’s liberation is interesting. After being placed on a tree trunk, it’ll typically scamper high at lightning speed. Then, earthbound observers are sometimes treated to a spectacular glide.

Flying squirrels are endowed with a membranous web of skin, called a patagium, between their fore and hind legs. When an animal throws its legs out upon launch, it becomes a mammalian parasail.

While the furry batmen can’t sustain flight, their glides can span hundreds of feet. They adeptly jig and jag to avoid limbs and trees, and sail unerringly to a desired target. Just before the squirrel lands, it throws its flat, wide tail upward, which acts as an air brake. Upon landing it runs to the opposite side of the trunk — perhaps a built-in behavior to thwart owls that might be in pursuit.

The only comprehensive treatise on Ohio’s mammals is Jack Gottschang’s book “A Guide to the Mammals of Ohio” (1981). In the southern flying squirrel account, he states, “No one has studied it in detail in Ohio.”

I’m glad there are intellectually curious researchers such as Althoff who attempt to unravel the mysteries of little-known creatures such as flying squirrels. Because of his work, we better understand their abundance, population cycles, reproduction, food requirements and preferred habitats.

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 southern flying squirrel in flight/Jim McCormac

Hocking Hills photo workshop: February 20-22

One of the most scenic regions in the Midwest is the Hocking Hills of southeastern Ohio, and late winter (really, early spring!) is a great time to be there. Debbie DiCarlo and I have planned a field-based photo excursion for February 20-22, and we'll visit some of the most scenic spots. Debbie is a sensational landscape photographer (many other genres, too), and an excellent teacher. Both of us love to work with photographers of all levels, especially those just finding their photographic feet.

To learn more about Debbie and her work, visit HERE. For details on the Hocking Hills trip, CLICK HERE, and for a list and descriptions of our other trips, GO HERE.

Following is a tiny pictorial sampler of Hocking Hills highlights, with brief commentary. Hope you can join us!

The Hocking Hills region is noted for its spectacular sandstone features. This is the inside of Rock House, a sensational cathedral of brightly colored rock.

The boulder-strewn lower gorge at Conkles Hollow. There are numerous gorgeous sites such as this, and winter is perhaps the best time to capture their beauty photographically.

Graceful evergreen hemlocks, Tsuga canadensis, give the Hocking Hills much of its character. Myriad hemlock-lined streams create numerous landscape photography opportunities.

Waterfalls abound, and winter can be the best time to shoot them. Depending on temperatures, spectacular ice formations can occur. Open water or ice, either situation is stunning.

Nearly 80 species of ferns can be found  in Hocking County, and some, such as this maidenhair spleenwort, Asplenium trichomanes, are evergreen. Late winter botanical photography opportunities abound, and we'll learn lots about flora and fauna on this excursion.

Believe it or not, the Milky Way can look like this in Ohio. There are dark skies in the Hocking Hills and if clear skies prevail, we'll try our hands at astrophotography. This is a fun photographic art form with techniques all its own, and DiCarlo excels at capturing the night sky.

CLICK HERE for details, and to register.

Horsefly eggs

Word to the wise (from the not so wise): keep up on your photo archival! If you're a frequently active shooter, as I am, it's MUCH easier to amass lots of "keeper" images than it is to neatly label and archive them. Eventually all of my photos make their way into well organized folders, and I can lay hands on anything in seconds flat. But, over the past year, I have let some photo archival duties lapse, and am spending lots of time getting everything caught up - with dreams of not getting behind on this stuff again.

One perk of sorting through and labeling material from the year past is reminders of great field trips. On one of these - a foray to one of my favorite regions, Adams County, Ohio - from last September, I had taken a photo of "mystery" insect eggs. Hundreds of the off-white cylindric eggs were neatly arrayed into a fortlike pile, artful in its arrangement.

I knew who I could ask about their identity - Laura Hughes, who I have mentioned many times before on this blog. She quickly came back with an answer; an answer you may not necessarily be pleased to hear.

Horsefly eggs!

While these brutish biters are not everyone's cup of tea, I've always liked horseflies, in part because of some species' wild op-art technicolor eyes.

A horsefly in the genus Tabanus, perched atop my car and ready to attack. I made this image in Erie County, Ohio back in 2013. Note the crazy eyes. I've been known to take bites in order to get photos, as HERE. And I'll take more bloody rasping bites for the team, I'm sure, in order to get ever better photos of the fantastic eyes of these amazing creatures.

Who, as it turns out, also have amazing eggs.

Snowy owl photography tactics - and things NOT to do

A gorgeous juvenile female snowy owl briefly catches your narrator with its piercing gaze. It's doing its Linda Blair/Exorcist trick - twisting its head 180 degrees to look straight behind. Owls have 14 neck vertebrae - double our number - which allows them such flexibility.

These visitors from the high arctic have irrupted big time into Ohio and adjacent regions, with new birds coming to light nearly every day. Probably 80 or so have thus far been reported in the state, and some of them have stuck around favored spots and become local celebrities.

I went to visit one of these birds this morning - the animal above, which was found last Friday by Doug Overacker and Julie Karlson at C.J. Brown Reservoir near Springfield. In the four days since its discovery, many people have visited as is nearly always the case when one of these white wonders appears near a large population center or is otherwise very accessible.

And as is always the case, people want to photograph the owls. And therein often lies the rub, as far as the owls are concerned. A natural inclination of photographers is to get closer, closer, closer. This may be just human nature, a lack of oomph regarding lens power, or the desire to frame-fill the bird and minimize the need to crop. However, close approaches put a sleepy owl on edge, and are apt to flush it. Just because snowy owls "hide" in plain sight during the day doesn't mean they're active. They hail from treeless tundra regions and are pre-programmed to roost in wide open spaces, typically on the ground. While a bird may opportunistically grab prey during daylight hours, like most other owls they are largely nocturnal. It's best to give resting birds a wide berth and enjoy them from a reasonable distance. Flushing one causes it to expend unnecessary energy, potentially alerts harassers such as crows to its presence, and depending upon location, may drive the bird across a road and into traffic.

If disturbances happen too frequently, the animal may leave the area. If it is spooked from a site in which prey was plentiful and forced to try and locate another spot that can meet its feeding requirements, the owl's chances of survival drop.

Fortunately, these mammoth avian predators (up to 5 lbs! nearly 5 foot wingspan! two feet long!) can easily be appreciated from distances outside of the owl's discomfort zone, but plenty close enough to admire well, and often get decent shots. It isn't hard to tell when your presence is bothering the animal. It'll fidget, stare at you for extended periods, possibly adjust its position, and if pushed too much, ultimately take flight.  A touchdown as far as snowy owl photos go is obtaining nice images, and the bird is exactly where it was when you leave.

While the bird's welfare should come first, there is the human factor to consider. Like it or not, you will probably not be the owl's only admirer. Other people will visit, and most of them will not appreciate the person who insists on making an irresponsibly close approach - and Hedwig forbid they flush the bird in front of a group of people! Many nasty people encounters have been spawned by such behavior, and no one wants that.

This is the lay of the land - the beach area at C.J. Brown Reservoir. Upon arrival near first light this morning, I saw the big white bird instantly. Its location is denoted by the red pin closer to the bottom of the map - it was sitting atop a raised berm along that section of parking lot. The other pin shows where I was when I made the first image in this post.

The gate to these parking lots is closed for the winter, so one must park in the lots along the north-south road to their right. As I walked in, I kept a few parking lots and the berms between them between me and the owl. I have no doubt that it instantly saw me when I appeared, but my distance was such that it paid me no mind. To get the over-the-back look from the owl for my photo was just a matter of patience, as it routinely scanned in all directions.

I am fortunate in that I've got Canon's superb 800mm f/5.6 lens, which greatly increases the distance that the photographer can be from the subject and still get good images. Nonetheless, this bird could be photographed well with lesser lenses, from similar distances, especially on days with better light.

Following is some wonky techno-stuff for photographers working a snowy owl from afar. Always use a tripod (sturdy one, hopefully!), as a solid base of operations is vital. If you don't already, learn to shoot in RAW mode regarding image preservation. RAW files are digital negatives that capture all the data, and are often thrice the file size of a jpeg (the latter file type compresses the image thus losing some data). The ability to crop and otherwise edit a RAW file and still retain detail is much greater.

This day was gusty, which presented stability issues. The camera/lens being firmly locked down on the tripod helped, but big telephoto lenses have huge lens hoods. Mine is about the size of a coffee can. The first thing I did was take it off, to prevent the hood acting as a parasail. The ambient light was still not very bright when I made my images, and I try my best to keep the ISO to 800 or preferably less, to help ensure clean mostly grain-free images. To do that, I opened the lens to f/5.6 - wide open - and had to drop the shutter speed to 1/160, with 0.7+ exposure compensation. Those settings gave me an ISO of 800, which was OK. To further help ensure a relatively sharp image, I shot in live view, which locks the mirror up, preventing even the slight shudder caused by the mirror's actuation. My Canon 5D IV has a touch-sensitive back screen, so I could just touch the part of the screen where I wanted the focus point to be. Finally, I set the drive mode to 2-second delay, which meant that I wasn't even touching the equipment when the camera fired. I then positioned myself as a wind block, although I tried to shoot between gusts. Resting snowy owls don't move much, making these techniques possible. If the bird did move its head during the 2-second delay, I just shot again. These tactics gave me some nice files that could be greatly cropped and tweaked later, and to the owl, it's as if I wasn't even there.

I had noticed several hundred gulls resting on the nearby beach, and foraging offshore. Being a huge gull fan, I headed their way after working with the owl. Gulls are awesome on many levels. They're beautiful, masterful aeronauts, excellent identification challenges, exhibit fascinating behavior, and some are great case studies in evolution.

This is an adult ring-billed gull, and it has captured a spotfin shiner, Cyprinellus spiloptera (I think). Naturally, once the other gulls saw this bird with its hard-earned meal, the chase was on. Shooting gulls in flight is great fun, and relatively low-hanging fruit on the photographic difficulty scale. I like to wait for some interesting performance, such as an aerial dogfight or just-caught fish to create a more interesting image.

After an hour of playing with the gulls, I ascended the low hill back to the parking lots where the owl was. Keeping the snowy in mind and figuring it was probably where I left it, I detoured north so I came into the lots as far away from the owl as possible. A quick glance showed that it was not where I left it. It was now in a tree - a few hundred feet away. With a photographer nearly under it. Having no desire to publically embarrass anyone, I've shaded out the person's body in the photo above so they can't be identified, but you can see the telephoto lens sticking out to the right. And the owl staring at the person from the tree to the right - probably about 40 feet away and that's way too close.

I imagine the person saw the owl where I had seen it, got too close and spooked it into the tree (NOT a typical resting spot). They then followed it, and from my unseen perspective from the distant corner of the parking lot I watched the next flush unfold. The person crept ever closer, and through my lens I could see the owl staring and fidgeting. It finally fluffed up and shook its wings and I knew it was about to bail again.

The flushed owl came straight my way as I stood quietly behind one of the berms, and alit not too far away. I imagine this is the type of shot the person was trying for, although I'm not particularly gratified by my effort due to the circumstances.

While a bit ticked at watching this go down, angry encounters generally do no good. I gave the owl a wide berth and worked my way to the other end of the parking lots to say hi to the photographer, who I didn't know but did recognize. Hopefully our cordial chat about owl welfare will help in future encounters.

If you do see a snowy owl - and this is the winter for it! - please keep a fair distance away and don't risk flushing the animal. Patience rules. If you wait long enough the bird will eventually do something - adopt interesting postures, preen, make a short flight to another spot, maybe catch a vole if you're really lucky. In the case of the snowy owl that was the subject of my previous two posts, I spent nearly eight hours watching it, and was rewarded with some wonderful photographic opportunities.

And if you do see inappropriate behavior on the part of one of your fellow owl-watching primates, please address it with civility. Loudly yelling across a field, angry confrontations, or other bellicose displays will probably not help; they'll likely make matters worse. A reasoned dialog might stimulate positive change. While there are exceptions, most people, including photographers, who unnecessarily disturb an owl may well not know any better. A casual chat about the birds and their amazing life history, habits and needs might be all it takes to help improve a situation.

Nature: Snowy owls once again making their way into Ohio

A snowy owls rests atop a Holmes County feed silo/Jim McCormac

Columbus Dispatch

December 17th, 2017

NATURE

Jim McCormac

Four years and two days ago, I wrote a column on snowy owls. That winter saw a massive invasion of these stunning, white arctic predators. At least 170 owls were reported from 59 of Ohio’s 88 counties.

Deja vu. In perfect harmony with an oft-cited four-year cycle, the owls are irrupting again. I’ve heard of about 50 owls so far, in perhaps 25 counties. One of these was a brief sighting of a bird near the Main Post Office on Twin Rivers Drive in Columbus.

This winter’s irruption isn’t confined to Ohio. Scores of owls have been reported in a band from Montana and the Dakotas east to the Atlantic coast and in adjacent parts of Canada.

The majority of Ohio reports come from Lake Erie, as is typical. Harbors and the lakeshore provide an abundance of food in the form of gulls, ducks and small rodents. Even in lean owl years, a smattering of birds are found near Lake Erie.

Small rodents called lemmings drive the great white owls’ movements. These small tundra-dwelling mammals have boom and bust cycles that peak about every four years. Apparently they reached a crescendo in the Ungava Peninsula of northern Quebec last summer, about 1,500 miles north of Columbus. This region also fostered the owl boom that triggered the invasion of four winters ago.

When lemming numbers soar, snowy owls respond en masse. Through some poorly understood homing ability, owls descend on lemming-rich tundra regions, while all but abandoning areas of low lemming numbers. Their frequency of nesting skyrockets, and nest success rates go up.

Scads of owlets are produced during lemming explosions. Once the arctic winter sets in and mammalian pickings get slimmer, these youngsters are forced to flee south. Seasoned adults tend to remain in the far north.

The most famous of the Ohio snowy owls is a bird that appeared on Thanksgiving Day on the farm of Orris Wengerd in Holmes County. Word rapidly migrated through the birding community, and owl enthusiasts soon converged on the scene.

I visited the Wengerd farm on Dec. 4, twelve days after the owl’s initial appearance. It wasn’t hard to find. While driving in on the adjacent county road, I saw the bird sitting in a field about one-third mile off. I drove into the farm and the designated parking area, and while getting out camera gear, the owl flew to the top of a feed silo about 100 feet away.

My intended short visit turned into more than seven hours, as like so many others, I became enchanted by the massive white bird. At one point, it spotted a vole in a pasture about 100 yards off, dropped from its perch, sailed down and bagged the rodent. It mostly rested atop silos and a barn — as with other owls, snowies hunt primarily at night.

At the time of my visit, about 700 birders had visited the farm. The owl remains as of this writing, and visitors probably number nearly 1,000 now. The Wengerds run a busy operation — mostly chickens and dairy cows — but have been amazingly hospitable in sharing their arctic visitor with all comers. On behalf of the birding community, many thanks to Orris Wengerd and family.

The snowy owl irruption of four winters ago spawned an amazing research project called Project Snowstorm, which studies the habits and movements of these owls. Visit that site at https://www.projectsnowstorm.org/.

And keep an eye out for large white birds. Snowy owls can materialize nearly anywhere. Please let me know of any observations.

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.