More fun with Southern Flying Squirrels

 

Yesterday dawned crisp and snowy, but plans were afoot to join Professor Don Althoff of the University of Rio Grande and other squirrel enthusiasts to conduct research on one of our most interesting mammals, the Southern Flying Squirrel (Glaucomys volans). The temps were in the low teens when Shauna and I departed Columbus early that morning, and it was probably about 20 F when I made this image in northwestern Athens County. Our squirrel "lab" was those distant woods.

The meadow above is dubbed the Dennis Profant prairie and is part of Hocking College's land lab. Dennis was a professor there, and a real jack-of-all-trades when it came to the natural world. A true natural philosopher, with an especially keen interest in moths. We lost Dennis in 2015 - far too early - and this prairie is a fitting memorial to him. HERE IS a short piece that I wrote about Dennis.

This was our crew on this snowy, blustery day. Almost all 14 of us. Our fearless leader, the indefatigable Dr. Althoff, took the photo. Almost everyone here has been on at least one of these Southern Flying Squirrel (SFS from here on) box checks. I think it was my fifth, time, Shauna's second, and some of these people have been far more times than that.

Our leader, Don Althoff, scales the 35 lb. ladder that must be lugged over rugged terrain. One of the large boxes that the squirrels use for winter roosts - and nest sites in the breeding season - is in front of him.

Don has 16 squirrel trails in about a half-dozen southeastern counties, and each has 25 of these boxes. My iPhone recorded a distance of about 1.5 miles to get around this one. Not far at all, but throw in the hills, fairly deep snow, and the equipment that must be hauled along, and it's a pretty good workout (at least for the equipment-haulers).

This was cool, and highly unusual. As Don placed the ladder and began scaling the tree to this box, I noticed something in the hole. A SFS! The curious beast was peeking out to see what was going on. Such behavior is very rare as I understand it. Normally the squirrels are all sacked out at the bottom of the box, but either this guy wanted a peek at the winter wonderland, or he heard our approach and wanted to see what was happening.

One of the 16 SFS that was captured that day. One box had nine SFS inside! Althoff has had boxes with 15 squirrels on a few occasions. Why so many (there is almost always multiple squirrels roosting together)? SFS are highly social, but heat plays a big role in the formation of these squirrely scrums. Pack three, five, nine, or 15 squirrels in a box and its warm as toast in there, or at least far warmer than the outside air temperature.

All Don's gear is specially designed for the squirrels and expedites their safe and speedy handling and release. Each is weighed, sexed, and given an ear tag with a unique number that allows it to be positively identified if recaptured. Other data is collected as well, and over the nearly three decades that Althoff has studied SFS, he's generated a mountain of information on this little-known completely nocturnal mammal. Oh, squirrel releases are possibly the coolest part of the process. the SFS is placed on a tree trunk, and usually as soon as its handler lets go, it races upwards, 20-30 feet or higher. Then, oftentimes, it launches into an incredible glide that must be seen to be believed. Winglike flaps of tissue extend between forelegs and hindlegs, and when stretched taut form wings. The squirrel cannot fly, in the sense of sustained flight, but the furry aerobats are quite dexterous and jig and jag around trees and branches. While rare, these flight/glides can be 150 feet or more, although one-third or so that distance would be much more common. When the SFS lands, it flips its broad, flat beaverlike tail upwards. This sends the animal's head upward and slows the airspeed considerably, allowing for an easy landing. Almost invariably the newly alit squirrel dashes to the other side of the tree. That's likely an adaptation to thwart would-be predators such as owls, that may have been following it.

The following is a quote from the book Mammals of Ohio, by Jack Gottschang (1981): "Perhaps because of its nocturnal and secretive habits, this squirrel has escaped close investigation by all but a few mammalogists; no one has studied it in detail in Ohio."

Gottschang's words are now sorely dated, and I'm sure he'd be glad of it. Because of Don Althoff's remarkable tenacity in studying the difficult to access SFS, we know FAR more about them and their life history.

HERE IS a link to another piece that I wrote about Don and his work, this one from my Columbus Dispatch column, Nature, dated January 1, 2018. I've got a few more posts about SFS on this blog, with many more pictures. Just type "Althoff" into the search box at the top upper left corner of the blog.

Southern Flying Squirrels!

A southern flying squirrel, Glaucomys volans, pauses nuthatch-like, headed down a tree trunk. Last year, about this time, I received an invite from Roman Mast to come to his place in Knox County to see an extraordinary assemblage of these furry paragliders. You can read about that trip RIGHT HERE, and it explains a bit of Roman's relationship with the squirrels and why so many visit his yard.

Well, Round II for me and the squirrels was last Wednesday. I got word from Roman that numbers were building - June is the peak month - so off I went to see my friend and his amazing mammals. Once there, we didn't have to wait long. Flying squirrels are strictly nocturnal, but don't wait very long to emerge once the sun has fully set. I asked Roman when the first squirrel would appear and he said "9:13". Darned if I didn't see the first shadowy movement of a squirrel high in the trees at precisely that time, and by 9:15 some animals were down to the feeders.

A flyer in a rare moment of repose, and it's only still because it's eating a kernel of cracked corn. These little speedsters race about at the speed of light, maneuvering up and around trunks and branches at speeds that make your head spin. It's as if they have Velcro for paw pads.

That isn't to say they always get it right. Squabbles between apparent alphas and lesser squirrels are frequent, and in some cases physical tussles lead to a squirrel falling to the ground from lofty heights. We saw this several times last night. It reminded me of someone with a dud parachute that sort of slows the descent, but they still hit the ground with a good thunk. Apparently there isn't time for the squirrel to spread its patagium (the loose flap of tissue between the legs that forms a sail when stretched taut) and catch enough air to sail out of the fall. But each time, utterly unfazed, the squirrel would bounce right up and back into the tree.

Here's a brief video of a few flying squirrels working the primary feeding tree. Turn your volume up to hear a nice symphony of singing gray treefrogs.

Thanks to Roman for so graciously sharing the squirrels with me, and many others.

Southern flying squirrels! Many, many!

I recently had the opportunity to tag along on one of professor Don Althoff's southern flying squirrel research projects. This was not my first time at the flying squirrel rodeo. I wrote about a previous excursion RIGHT HERE.

The article mentioned above goes into the nuts and bolts of Don's research, and the biology of flying squirrels. This post is more a pictorial documentation of my recent excursion with Althoff and company.

We had a sizable group on hand, as evidenced by the photo above (and two or three people are not in the photo). Many are Don's students, and others are just smitten with flying squirrels, and interested in the dynamics of this interesting research. I have met very few academics who are as good at stimulating an interest in conservation and biology as Don is. He welcomes students and others in a hand's-on immersion into the world of one of the world's most intriguing mammals. Accompanying Don on one of his "flying squirrel trails" is an experience that no one will soon forget, especially if the squirrels cooperate.

Don Althoff, who teaches at the University of Rio Grande, atop a ladder deep in an Athens County woodland. He's got nearly 350 "flying squirrel boxes" up in trees on a number of southeastern Ohio sites. This particular woodland has about 25 boxes, and investigating them is a lot of work. A ladder must be toted along, as well as a bunch of research equipment.

Flying squirrels reliably use these boxes as winter roost sites, as well as for nesting. There's always a mood of expectant anticipation when Don scales the ladder to check a box. The throng below awaits his yea or nay, and if a yea, down comes the box for inspection of its inhabitants.

The first occupied box we encountered had, as I recall, two squirrels. Here's the box down on the ground being prepared for squirrel extraction. These little mammals move at the speed of light, so a careful protocol must be followed to ensure the subjects do not escape. In all, we located 18 squirrels, including a remarkable 13 in one box. That number tied Don's best box number, but a few days after this work he found two more boxes, each with 13 squirrels. So, will he find 14 in a box someday? Time will tell.

Each captured squirrel is weighed, various other data is collected, and it is carefully photographed before release.

Flying squirrels sure are cute, and seeing one like this always prompts oohs and ahhhs (or awwws). Note those sharp, long yellowish incisors peeking through, though. Flying squirrels can quickly cut away the hardest of hickory hulls. Experienced researchers soon learn to handle these wee beasts with the utmost respect.

A captured flying squirrel lays into a gloved hand. They get feisty when handled, understandably, and if given a chance may nip the hand that holds them. While those gloves are pretty tough, a squirrel's saberlike teeth can go right through, and I'm told they hurt.

This student got a lesson in aversion therapy in regards to careless squirrel-handling. The little mammal punched right through his glove and drew blood. Fortunately rabies and other diseases are unknown in this species, but sharp teeth sunk into flesh still hurt and bitees quickly learn to watch how they hold these animals.

Althoff demonstrates a proper hold. We can see the squirrel's amazing tail, which serves as parasail and rudder when in flight. Along with the patagia - winglike flaps of tissues along the body - the tail acts as a wing on the squirrels' amazing glides.

A squirrel just released and plotting its next move. They recover from the trauma of capture quickly and dart aloft. A flying squirrel going full tilt up a trunk is an amazing thing. They can move with ridiculous speed, and grip as if Velcro boats their paw pads.

The brown pelage of a flying squirrel blends remarkable well with this dead tree snag. Dead and dying timber, and their attendant cavities, are vital to the survival of flyers. This mammal is totally nocturnal, which is why people seldom see them. They require cavities for roost and nest sites. And there are a lot of flying squirrels in need of cavities, at least in wooded areas. There might be 4 or 5 flyers per acre, as compared to 1 or 2 gray squirrels in the same area.

A flying squirrel prepares to launch into space. First-timers are always dazzled by their inaugural view of a flying squirrel "flying". If an Altoff squirrel check is fruitful, as this one was, participants are sure to see glides. Released squirrels are placed head high on a tree trunk, and soon if not instantly dart high aloft. Then, usually, the squirrel will launch into space, arcing between limbs and gliding away.

Shooting "flying" flying squirrels is a tough photographic challenge, and this shot is no award winner. But it shows well enough the furry cape outstretched into a wing suit, with the rudderlike tail helping with steering. While these squirrels cannot produce sustained flight, their glides are incredibly aerobatic and can extend the length of a football field.

In all, a fun and highly educational day learning about Ohio's most common woodland squirrel. I thank Don Althoff for his generosity in sharing his work and subjects with interested parties, and creating awareness of one of our little-known mammals.

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