Beaver, oiling up

The following video shows something that I bet you've never seen. It was definitely new to me. Those ultimate cam-masters, David and Laura Hughes, sent along a new crop of animal videos from one of their magical Monroe County game trails. This one depicts a Beaver, Castor canadensis, maintaining its pelage. Dave and Laura had sent along another Beaver video previously, and I expounded a bit about their engineering feats IN THAT POST.

This time around, the Beaver has the good manners to stop right in front of the trail cam, plunk down, and begin oiling its fur. Beavers have a pair of glands located near the tail - the castor glands - that exude an oily water-repellent secretion known as castoreum. The castoreum is the fourth tier of protection insulating the animal from the icy waters of winter. A beaver has a dense layer of fat, overlain by a dense cloak of short underfur. Overtopping that are longer and coarser guard hairs. The final protective coat is the castoreum, which we see the beaver applying in Dave and Laura's video. With all of these protective layers in place, water has no chance of penetrating to the Beaver's skin, and the furry engineers can operate with impunity, even in the frigid winter waters.

People have found uses for castoreum, too. It is used in various products as a food additive, and also in some perfumes. Glamorous models strutting the runways scented with Beaver castoreum probably do not know that fur trappers also use the pungent mask as a lure for other animals.

Thanks, as always, to David and Laura for allowing me to share their work.

Those hard-working Beaver (with video)

 

A Beaver, Castor canadensis, at his work station. I photographed this individual a few years back in Delaware County, Ohio, as the animal busily girdled huge Eastern Cottonwood trees along the shoreline of a lake. If a tree is too large to gnaw through and drop, Beaver will often girdle it, which eventually kills the tree.

 

Beaver are the consummate mammalian engineers, and their labors modify their environment to a degree that is probably unmatched by any other among our mammals (excepting Homo sapiens). These animals are clever, and hard-working to a fault. I've had the good fortune to see them on many occasion, and see the fruits of their labors many times. But few of us will experience the views of a Beaver at work that is shown in the trail cam video later in this post. David and Laura Hughes have been at it once again, and outdone themselves with this clip.

 

We should be grateful that Beaver are still around and making wetlands. The pelts of these animals have long been highly valued, and the pursuit of Beaver furs led to their extirpation in Ohio by 1830 or so. Eventually laws were enacted to govern their protection, and populations began to increase. Beaver began to trickle back into the state in the early 1900's, and by 1947 Ohio's population was estimated to contain 25 colonies in 11 counties. By 1972 their ranks had swelled to over 4,400 in 37 counties, and just four years later (1976) an estimated 7,500+ Beaver ranged over 40 counties. Today, there are probably in excess of 27,000 animals in the state, in all 88 counties. Trapping of Beaver is highly regulated, and current prices for a large grade A pelt is about $25.00.

A Beaver slices through the still waters of a pond that he and his predecessors created in northern Michigan's Presque Isle County. Few mammals are as at home in the drink as are these flat-tailed swimmers. A Beaver's entire life is spent in or adjacent to water, and all of their efforts go towards manipulating the hydrology of streams to better suit their purposes.

The animal in the above photo was a big 'un. A robust specimen can tip the scales at 70 lbs., although 40 lbs. would be a more typical poundage. You'll often hear a Beaver before seeing it. When danger is spotted, the animal will often slap the water's surface with its paddlelike tail, which creates an astonishingly loud SMACK! That sound alerts his fellows to potential peril, and then the tail-smacker will submerge. Extraordinarily oversized lungs allow it to remain below for up to 15 minutes.

This Google Earth photo shows an incredible Beaver-engineered and maintained wetland complex in southern Ohio's Lawrence County. Two huge dams (traced in red) back up two ponds in the small valleys of a forest. The area outlined in blue - which disappears off the left side of the image - is a fantastic wetland spawned in the soggy overflow from the Beaver's primary ponds. A well-developed dam can be in excess of 50 feet in length, and often has a sinuous shape as these two dams do. The Beaver are dligent about maintaining these structures and keeping water levels at precisely the levels that their needs dictate.

I stumbled into the wetland complex above in 1999, and was awestruck by its compexity. The wetlands in the wake of the dams' outflow contained a remarkable diversity of flora; far more plant species than would have been present had the Beaver not taken up residence. The botanical diversity in turn sparks an enormous spike in animal diversity. We found American Bittern and Prothonotary Warbler in this wetland, both of which are rare in that part of Ohio. Dragonflies and other aquatic insects abounded, as did scores of other wetland-dependent animal life. When I first saw this Beaver wetland about a dozen years ago, it was obvious that the dams had been in place for some time. And as the Google Earth image is a recent one, they're obviously still there, and hopefully will be for some time to come. I want to make a return visit next summer, and marvel at this engineering feat firsthand once again.

If you regularly follow this blog, you may have seen the exceptional videography of Bobcat and River Otter made by David and Laura Hughes, which they kindly allowed me to share. Well, they've outdone themselves with this video, also made in Monroe County, Ohio, which shows a Beaver hard at work as it labors to drop a tree. Turn up the volume and you'll hear the sound of gnawing as the oversize rodent busily endeavors to bring down the tree. Note too the size of the wood chips that spew from the animal's maw as its huge incisors make mincemeat of the wood.

Thanks again to David and Laura for once again sharing their work with us.

Mammals of the North Woods

My recent NettieBay Lodge Expeditions in northern Michigan's Presque Isle County were mostly about birds, and we did well - 153 species in a week. We also learned a lot about plants, and I wouldn't even try to tot up that total list. In short, we look at anything and everything, but always prioritizing the birds. After all, a bird can fly off so it's always best to immediately avail one's self of a viewing opportunity before the bird in question decides to bail.

Another group that we did well with was mammals. I already blogged about the porcupines and their dens, but that prickly rodent was only one of seventeen mammal species that we observed. Followng are a few of the ones that I managed to turn into pixels.

There are scads of beaver up there, and we saw a few true jumbos. But none of the chunky tail-slappers came in range of my camera. Here's some big, in your face, evidence, though. The local beavers of this particular lake had recently dropped this bigtooth aspen, at least in part so they could get at the succulent upper branches. Note how they've stripped the bark from the upper part of the tree, down there at the far end.

A striped skunk waddling through a field and rooting about for grubs. I initially misidentified this one. How, you may ask, did our blogger manage to botch the identity of one of the most recognizable mammals in North America? Well, it was broad daylight, and this skunk was way off in a field of tall grass. I could only see little patches of it as it rustled about, and my first thought was, badger! After all, badgers are white and black on the face and probably more prone to be out and about during the day.

Anyway, I tossed the car to the roadside and ran towards the animal in the hopes of working my way closer. It didn't take but a few lopes in the beast's direction before I saw what it truly was. Oh well, it allowed me fairly close and I ws able to make a few photos. Skunks are actually fine-looking animals if one can get over their reputation.

Eastern chipmunks were everywhere. The cute little busybodies are generally in perpetual motion. One individual was making regular raids on the NettieBay Lodge feeders, stuffing his cheeks with peanuts. Once full of loot, he'd race off to a distant woodpile to cache them. Try as I might, I never managed a shot of the chippy with cheeks bulging out to nearly double the size of his head. HERE'S a piece I wrote a while back about chipmunks and the sounds that they produce.

There were also scads of eastern gray squirrels, but with a twist - most of them are melanistic; so-called "black" squirrels. Maybe because I am used to seeing the gray-colored gray squirrels, I can't get enough of these exotic beauties. There were normally colored individuals, but they were outnumbered by these dark versions, which also appeared to be more aggressive.

A genetic trait causes the dark coloration, and litters of squirrels can have both gray and black individuals. Black squirrels have long been known from scattererd locales in Ohio, but they appear to be becoming more frequent.

King of the squirrels, a red squirrel, sometimes known by the monikers chickaree or red jimmy. They are hyper aggressive and rule the roost. A red squirrel will easily drive off much larger gray or fox squirrels despite being dwarfed by these bigger species. Their loud shrill scolding notes are quickly learned by birders working the north woods.

We stopped at a convenient state park for a break, and noticed a thirteen-lined ground squirrel loitering about the mowed grassy lot in an uncharacteristically bold fashion. Sure enough, just like the chickadees at your feeder, this guy had been the recipient of handouts and had become acclimated to people.

I don't condone feeding ground squirrels picnic fare, but if others do I'll take the photo ops. Thirteen-lined ground squirrels are not exactly extroverts, but the lure of this chip was too much, and he slowly jigged and jagged nearer.

Finally, with a gentle tug he took the chip and raced to one of his holes to enjoy the spoils. I suppose the positive side of this unusual taming of a normally wary mammal is that people who would never otherwise see one of the handsome little ground squirrels get to admire one up close and personal, and hopefully become more interested in the natural world as a result. I made a more in depth post about ground squirrels HERE.

Finally, a life mammal for your blogger! A northern flying squirrel comes into the peanut feeder at NettieBay Lodge. I had heard these up here last year, but never laid eyes on one. This year, they had discovered the feeders and we noticed one gliding around one evening. So, we pulled up some chairs on the back patio and it wasn't long before one of the furry little fellows swooped in and lit on a feeder.

Just like the southern flying squirrels down here, this one was tame as a kitten and I was able to approach it within five feet. It cared not a whit, armed with the knowledge that it is probably 100 times faster and more agile than your camera-wielding blogger.

I love watching flying squirrels, and am delighted that the lodge setup is attracting them. These feeders are full of great birds during the day, and now at night we can watch these tiny squirrels. I don't know if you've ever seen one of these, but flyers are about the fastest arboreal mammals you'll ever want to see. They'd make Spiderman look like the clumsiest of oafs. It's as if they've got velcro for footpads, and an excited squirrel will roar up, down, and around the trees at astonishing speeds, occasionally launching into space and gliding to another tree. Quite a show.

We're doing two more of these forays at NettieBay in late May of next year, and attendees will get to see many of these mammals in addition to scores of birds, plants, and other interesting things not to mention beautiful landscapes at every turn. If you are interested, contact Jackie at NettieBay HERE. We keep the groups to ten people each, and I believe they're already over half full so let her know soon if you can make it.