Sunday, December 27, 2015

Rats of the Trees: The Eastern Gray Squirrel's (Sciurius carolinensis) Life History

(A gray squirrel threatening its "picture-hunter" with roar-like yowls and rapid tail flicks deep in the cover of a white pine tree.) The Eastern Gray Squirrel, Common Gray Squirrel, Bushytail, Tree Rat or simply Grey (or Gray) Squirrel is possibly one of the most common and most overlooked creature in the US. Some people merely call these animals "tree rats" and think them boring and useless. Some people keep them as pets, but this is cruel and makes most of the the squirrels miserable with longing for their treetop territories. But wild squirrels can even become quite tame, especially those in theme parks and in the trees above outdoor restaurants, eating and begging for popcorn that is tossed to them or snatching french fries from the hands of unsuspecting observers. This, of course, makes a common animal get a new respect for its courage to approach enormous beings many times larger than itself. But some get a practical use from hunters and survivalists. Squirrel meat is common winter and spring fare in the Appalachian Mountains, and a sought-after and regularly eaten delicacy in England (where gray squirrels have recently been introduced). Squirrel Gravy, Squirrel Dumplings and Fried Squirrels are often seen as local dinner. Since there are many squirrels, and that gray squirrels are the second most hunted animal in the US (only ranking after the white-tailed deer), you can imagine that rural squirrels can be much more cautious than the squirrels of residential areas. Squirrels frightened by the approach of larger animals (humans, bobcats, wild canines, pets, raptors, etc.)  will normally do one of two things. The least common response is that the squirrel will clamber to a low, flat tree branch and squeeze into a tight ball, paws folded, and reclining on its haunches. It will then raise its tail and lay it across the back and between the ears. After it feels secure, it will make a roar-like yowl, as quoted above, that resembles an old, creaky wooden door. You have probably heard this call before in the winter, issued by angry squirrels that reject the courting displays of other squirrels, but this will be extensively discussed later in the post. The threatening squirrel, after posing and calling, will either come down the tree or ascend the tree, depending on if you back away or advance forwards, respectively. The other escape method of the squirrel, sometimes done after the first method, involves the squirrel rapidly ascending a tree. This is usually not just any tree in the woods, however. A frightened squirrel will give a short, abrupt chase that ends with the squirrel being "treed", or trapped in a forest's canopy. Why the squirrel does this is for an unapparent reason, but with deliberate contemplation, it is easy to reason that if a squirrel scales a many-branched tree, bobcats and gray foxes can scale the tree after it much too easily. If a squirrel ascends a sapling or a dead tree, predators such as squirrel-dogs, coydogs and hungry bears can fell the tree and ingest the dazed squirrel. So squirrels will normally engage a chase across deadfall such as elevated logs and exposed stones, normally retreating to the trunk of high, almost branch-less self-pruning trees such as oaks and tulip-trees, using the aid of ramps that usually are half-fallen trees, woodpiles, or powerlines.
(A gray squirrel enjoying some tasty catkins or tree pollen, one of the few foods that spring holds for seed and nut loving squirrels) Squirrels eat anything from flowers, nuts, leaves and fruits to insects, bird eggs and fledglings. Hickory nuts are the favorite food of squirrels. From late spring to early winter, squirrels collect food on the roam to eat, mainly while endeavoring on other chores. But starting in summer, gray squirrels gradually build up excess food in caches. Each squirrel may have hundreds of different caches in its territory, some only holding one or two nuts. This behavior is called "scatter-hoarding", and is a beneficial part of the propagation of forest trees because squirrels forget the location of a good portion of their food stores and caches. These caches are highly desired by crow-related jays, grackles and blackbirds. One of these birds (most of the time a jay), will watch a squirrel from a low branch, remaining silent until the squirrel has finished burying its spoils. The jay will then swoop to the ground and dig up the food, flying it into the trees where it can crack and eat the nut with its sharp, thick bill. But if a squirrel notices a jay watching it dig, it will pretend to bury its food and hide its bounty in its cheek pouches. Then, while the jay excavates the false cache, the squirrel will dig another store close by.
(A warm-weather drey high in some entangled sycamore branches)
Squirrels make three kinds of homes. The first is used in cold weather, and either looks like a colossal leaf pile or a worn tree hole high in the canopy. This nest may be used by several squirrels in the same territory. These groups of squirrels are called scurries. The second type of squirrel nest is the nest of a bachelor or nut-collecting squirrel. It appears as a thick clump of dead leaves and can be exactly the same as a crow's nest, and it sometimes is the abandoned nest of one of these birds. This nest can also be used as a universal warm-weather shelter for all squirrels as well. Squirrels reside in one last shelter, one that is only used to raise young in early spring and late summer, during each breeding season. Many squirrels will make small, soft nests of leaf litter, gnawed bark, and old fur, sometimes using pieces of garbage, either in open branches or in tree holes. Squirrel nests are known as dreys or drays. Gray squirrels have some intriguing behavior as well, being extremely social with one another. Boars (males) are assertive and often tussle with their neighbors. Sows are more docile, being instructive and strict with her kits (young). Pairs of breeding squirrels isolate themselves and frighten away any squirrel or animal that may threaten them. Boar squirrels will chase sows up and down multiple trees throughout winter, sometimes being rejected and attacked by chased sows, or stopped and threatened by competing boars. Once the male and female squirrel have settled down in a breeding drey, they both work to provide food and care for the nestling squirrels. Squirrel kits, as soon as they can see, hear and run, are taken out into the trees to be taught. The mother takes the job of teaching the young, and the male normally leaves. These young squirrels will soon leave their mother and make easy targets for hunters, aiding in the creation of a "Spring Squirrel Season". Some gray squirrel look-alikes and similar species are rarer, but are often seen in their specific habitats. The Red Squirrel, Pine Squirrel, Chickaree, Fairydiddle, or in the Southern Appalachians, the Mountain Boomer, is a noisy and tiny squirrel that is also unique. It is native to only high-mountain forests in spruces, firs and pines, feeding almost exclusively on conifer cones. They are half the size of a gray squirrel, have a bright red coat, and possess long, tufted ears. Another squirrel is the fox squirrel, which can be black, red, or gray, identified by its enormous size and yellow belly. The fox squirrel normally lives alone, chasing other squirrels, even some of its own kind, away from its home in open areas. They spend the most time on the ground of any tree squirrel and are the largest squirrel in North America. Fox squirrels live in fields with fruit and nut trees, feeding mainly on walnuts, butternuts, drupes (fruit and berries), green plants, flowers and some animal matter. fox squirrels rarely venture into forests. They will kill or chase away gray squirrels to claim their own large territory. Flying squirrels (both the Northern and Southern) are also easy to confuse with gray squirrels while on the ground. Flying squirrels are secretive, nocturnal and look more like a bat than a squirrel when gliding through the air. Their glides are often from branch to branch, used to gain speed quickly. These are sometimes identified at dawn and dusk when speeding to their tiny, hidden dreys. While the other squirrels mentioned are tree squirrels, the next is the only native member of the chipmunk family (family being used only as a collective term), a group of small, striped ground squirrels. The Eastern Chipmunk, a striped relative of western ground squirrels and "striped gophers", is the only native member of its family anywhere near the Southern Appalachian Mountains. Some predators of the squirrel include raptors, snakes, foxes, coyotes, bobcats, pets and humans. Also, the least weasel, the typical European "weasel" that is also native to the Southern Appalachians, will go on killing sprees and slaughter massive amounts of rodents (including chipmunks and squirrels), birds, herptiles and anything else that moves up to the size of a rabbit. They will store these carcasses in their tunnel or the tunnel of a prey animal (such as a rabbit, ground squirrel, shrew, mouse or vole).
(A squirrel feeder set on one of two backyard hickory trees , which never drop their fruit due to hungry squirrels.)To attract squirrels, set a squirrel feeder full of deer corn. These wooden birdhouse-like structures can be nailed to a tree. I recently set one in winter and watched my backyard squirrel population grow by at least two individuals in the first couple of days, and after almost a week, there are twelve squirrels from the five that I used to see. If you are interested in getting a closer look at or catching a squirrel or chipmunk, set a small-sized live trap with some kind of nut or seed (squirrels typically prefer hickory nuts and pecans) as bait. Put it on or behind the trigger plate, and it may be good to smear a nut/peanut butter mixture on the trap's trigger plate to add the extra pressure of the eating squirrel's hands. Also, leave a trail of mediocre food in front of the trap to entice your quarry. It should take a few days, if you are lucky, to catch a squirrel (if you're lucky enough to even catch one) and caution should be taken when releasing a sharp-clawed, sharp-toothed angry squirrel.
(This trapped sow squirrel may look sodden and miserable in its rainy atmosphere, but I assure you that it was released without harm. The squirrel is actually better off; it received a fattening meal of hickory nuts and regained its freedom quickly.)
(Two gray squirrels climbing and calling just outside their cold-weather drey. Can you spot the site of the drey?)
(Here are some gray squirrel tracks in sand under the cover of winter box elder trees)
(Squirrel tracks in snow, which lead to an uncovered mast cache.)
(A gray squirrel investigating on two legs, acting much like a tiny bear.)
I hope you now appreciate squirrels for what they are and won't overlook these animals like many other people. So whenever you see a squirrel, think about its interesting lifestyle and amazing tactics. If possible, watch it as well; it shouldn't disappoint you. Happy Trails, Critter Cade

Wednesday, December 16, 2015

Little Lynxes: The Territorial Bobcat

To the beginner naturalist, as a matter of fact, to any naturalist, this small tree is undeniably a redcedar. But to the experienced naturalist, this is a property boundary; one of mother nature's blazing evidences that a feline has claimed the nearby area as its home. These marks are called "scrapes", and have a variety of meanings. This one was the sign of a Bobcat (Lynx rufus). The bobcat gets its name from its "bobbed" (or short) tail. The name Lynx comes from the family of large, northern cats that share the common name lynx, though the bobcat does not. The name rufus comes from the reddish color of bobcat fur that matches the bark of trees and leaf litter. Bobcats are often plainly called "Wildcats" in the Southern Appalachians and are trapped for their luxurious furs. Bobcats hunt anything from insects, lizards and fish, to mice, rabbits, even foxes and small deer. They normally drag their prey into the trees to feast on it later. Bobcats also have ground dens, usually distinguished by worn areas leading to crevices in steep, talus slopes that are hard to access. They can be called in by hunters and naturalists by blowing on a leaf of stilt grass, or any other wide-leafed grass. It makes a hoarse, squeaky noise, similar to an injured rabbit. Hearing and sight are the bobcat's main senses, unlike the scent-oriented canines. Bobcat kittens are well guarded in secret locations that are very hard to find. In the night, bobcats will sometimes call into the night with a yowl that sounds like a "screaming woman". Bobcats can range from the size of a pet house cat to a whopping fifty inches and a report from a New Hampshire roadkill specimen was said to have reached sixty pounds! Though bobcats normally eat rabbits (in most places), hares (in the North), and cotton rats (in the South), bobcats will sometimes kill coyotes and small deer, and five non-fatal but very dangerous attacks on humans have occurred in Florida, Massachusetts and Texas. Bobcat tracks aren't deep, possessing four toes and no claw marks. Their tracks are larger and wider than feral cat tracks as well, and are most often seen through snow or mud.  Bobcat  feet are wider than feral cat tracks to help the animal tread over deep snow and loose terrain.
(Bobcat tracks across a beach, probably left from a search for cormorant eggs or dead shad and herring. The water adjoining the area is a freshwater inland reservoir. Note rain marks in the sand that suggest precipitation around the time of the bobcat's prowl.) Bobcats are strange in their behavior, being camouflaged but not very afraid. Their favorite hiding places are high in trees that match their colors. Bobcats are relatively solitary except for the breeding season, and they only make noise in the breeding season as well. I have seen three bobcats locally in East Tennessee in three different locations that varied in elevation and habitat. One was a brief glimpse of a grayish bobcat sliding in a stand of scrub pines several miles outside of Elizabethton. The next was a crouched, brownish bobcat that was watching the area from a red oak log in a patch of stilt grass at the foot of Bays Mountain in Kingsport. The next was a reddish bobcat that was standing halfway in a hedge of redcedars in between Kingsport City and Blountville. The signs of bobcats are truly much more common, and I have seen too many of those to count. Just follow the tracks, let out a call, and you may see this:
(Clyde, one of Bays Mountain's Bobcats who recently escaped, yawning to show off his long, sharp fangs. But don't worry, escaped bobcats have been caught and retrieved safely in the past.)
Happy Trails, Critter Cade

Sunday, December 6, 2015

The Water Witch and the Snakebird (The Pied-billed Grebe and Double-crested Cormorant)

(Picture: A Pied-billed Grebe wintering inside Steele Creek Municipal Park)
One of the strangest birds that I look forward to seeing during the migration of waterfowl in East Tennessee throughout winter is the Pied-billed Grebe (Podylimbus podiceps). It is a tiny, goose-like bird and is seldom seen flying. The reason is that it migrates at night. Instead, it paddles in lakes and rivers during the day, diving underwater quickly to escape predators. They can stay underwater for quite a while, only to pop up in another place that may be in dense cover. In more detail, the bird resembles a gosling more than an adult goose; their feathers are soft and downy for their whole lives. More grebes also flock to Tennessee; the Eared, Horned and Red-necked Grebe, but the Pied-billed is the only common resident, with the exception of the Red-necked Grebe spike of March 2014. But yes, the Pied-billed Grebe does breed and nest in Tennessee. The pair of birds call with monkey-like yodels and join in secluded marshes. There, they build a floating nest that they anchor in the water under the dense cover of cattails and sedges. After incubating the eggs, the parents carry their young atop their backs and will feed them their own feathers. But this charming bird, possessing names such as Carolina Dabchick, for its resemblance of a baby bird, and Dive-dapper or Dipper for its underwater swimming abilities, is also thought of as shy and secretive, earning it names such as Hell-diver, Devil-diver and Water Witch for its abilities to seemingly disappear while swimming. All in all, however, the tiny grebe is a harmless migrant bird that eats minnows, crayfish, dragonfly larvae and other small aquatic creatures.
(Picture: A glossy male water turkey flying over a reservoir in Northeast Tennessee.)
The Double-crested Cormorant (Phalacrocorax auritus), or "Shag" is a bird that's not all that well-known. It is falsely accused of damaging sport fisheries, though they impressively do eat some large game fish. They are large with shiny blue-black feathers and a bare yellow face, complete with beady blue eyes and two crests. Cormorants are large birds as well, earning them the name "Water Turkey". This bird is a member of the heron family, customarily nesting in rookeries with Great Blue Herons and Great Egrets. The young birds are often exposed to direct sunlight, so the parents will shield them with their wings. Also during the breeding season, the adults make deep grunting sounds which can startle one into thinking that they are confronted by a feral pig. Another name, "Snakebird", originated in its serpentine methods of swimming: only the cormorant's large neck is at the surface, while the body drags along underwater. They also have impressive deep dives. However, after several of these dives, the cormorant becomes waterlogged. You see, unlike the ducks that have waterproof feathers, the heron-related cormorant does not. Instead, the birds have to spread their wings like a sail and expose their body, sliding in slight breezes over lakes to sun and wind dry. This display is often seen, especially on cloudy days where little sun is present. Another very unusual habit of this bird is also commonly seen in vultures. They make roosts in a certain tree, and many adult birds flock there to sleep. After a while, the processed-fish droppings coat the leaves so badly that it kills the roost tree. The white marks from droppings, or "chalk", helps you locate a roost.