Owls Aren't Wise and Bats Aren't Blind (6 page)
Red oak acorns germinate much better underground, and burial is almost a necessity for butternuts, black walnuts, and hickories. Indeed, it’s estimated that perhaps 95 percent of all hickory trees come from nuts unwittingly planted by squirrels. Thus the relationship between the gray squirrel and nut trees is really symbiotic: the squirrels require nuts in order to survive, and the nut trees require squirrels to plant them. As an added complexity, researchers have learned that gray squirrels promptly consume white oak acorns, which sprout soon after they fall, but bury red oak acorns, which need to spend the winter underground in order to sprout effectively in the spring. Again, this arrangement benefits both tree and squirrel. What a superb example of nature’s intricate interrelationships!
Red squirrels also cache food, but in a far different manner. Their strategy is to fill storehouses—a hollow tree or log, or an underground area— with as much food as they can pack away for the long winter months. Particularly where the seeds of coniferous trees are their main food supply, these caches can be enormous, sometimes numbering two or three thousand cones. These represent such a fine supply of seeds that the U.S. Forest Service sometimes appropriates them for use in starting conifer seedlings. This is not as harsh as it sounds, for the stolen cones are replaced with corn or other suitable food to see the little hoarder through the winter.
One of the more amusing sights in nature is to watch a red squirrel transporting pine or fir cones to its cache, or from cache to feeding site. Usually the squirrel grasps the cone by one end with its teeth, so that the little creature looks for all the world as if it’s puffing on a grotesquely large cigar!
No picture of squirrel food sources would be complete without mention of backyard feeders. The popularity of feeders has exploded in the past few years, particularly in suburban areas, though a great many rural residents have feeders, as well. The proliferation of rich supplies of sunflower seeds and other avian goodies has had a major and largely unintended effect in helping gray squirrels expand both their numbers and range in areas where nuts are scarce or almost nonexistent.
Squirrels—both red and gray—at feeders are extremely controversial. Humans who provide and stock feeders divide neatly into two camps: those who loathe squirrels and those who enjoy them. My wife and I are among the latter.
Those who detest squirrels at their feeders will go to almost any lengths to defeat them. Businesses are built on the manufacture and sale of “squirrel-proof” feeders (some more successful than others), and at least one book has been written on the subject. On the other side, there is an organization for squirrel lovers.
Without question, squirrels consume an awful lot of birdseed, creating an added expense that the homeowner may not want. It’s also undeniable that squirrels are astoundingly clever at circumventing obstacles designed to keep them out of feeders. It’s a little like trying to pick a lock: it can be done, but not easily! Thus, some people regard squirrels as unwanted, expensive nuisances and take umbrage when the squirrels defeat their anti-squirrel efforts.
On the other hand, many people enjoy the antics of squirrels as much as they appreciate the beauty and variety of the birds attracted to their feeders. To them, the extra seed consumed is a small price to pay for the double pleasure of observing both birds and squirrels. Ultimately it’s a highly personal decision, and there’s room in the world for both squirrel haters and squirrel lovers.
The actual eating habits of the two species are as different as their principal food sources. Gray squirrels eat nuts pretty much where they find them— here, there, and everywhere. Reds, on the other hand, have favorite feeding places, frequently on stumps or a fallen log. There, huge middens of cone scales build up, as revealing of the squirrel’s presence and habits as are the kitchen middens of human origin, so eagerly sought by archaeologists. Such squirrel middens will commonly fill a bushel basket or more.
Watching a red squirrel shuck a cone to get at the seeds is an edifying experience nearly as humorous as watching it transport the cone. Holding the cone in its front paws, the squirrel gnaws with astonishing rapidity, cone scales flying in every direction. Simultaneously, the front paws rotate the cone in a manner highly reminiscent of a human eating corn on the cob. In an amazingly short time, the cone has been reduced to flat scales on the ground, while the seeds now reside inside the squirrel.
Red squirrels are also great hands for temporarily storing certain kinds of food in trees. When a late-summer mushroom or an apple, some distance from an apple tree, is seen securely placed in a low crotch, the culprit is almost always an industrious little red.
Allusion has already been made to the very different personalities of these two species, but nowhere is this more evident than in their vocalizations. In keeping with their generally more sedate deportment, gray squirrels speak sparingly. Aside from high-pitched alarm calls of young squirrels being attacked by a predator, the gray’s voice is confined to something that is usually—though inadequately—described as a bark. Although these sounds are of short duration, they are nothing like the bark of a dog. Rather, they’re thin and raspy, somewhat akin to the sound of a rough file being drawn quickly over a surface.
Red squirrels are an entirely different proposition. Far more hyperactive than their big relatives, the little reds have a wide range of vocalizations— most of them seemingly expressive of particularly vile and opprobrious thoughts!
The characteristic red squirrel sound most often heard at a distance is a long, high-pitched
chirrrrrrrrr
that can last for more than ten seconds. This sound can be approximated by trilling an
r
continuously on a high note. Far more interesting, however, are the red’s other sounds, which can best be appreciated at short range as part of a full-scale audiovisual presentation.
Red squirrels love to scold. At the slightest opportunity they indiscriminately scold humans, birds, and animals that are unfortunate enough to impinge on what the reds regard as their exclusive domain—but most of all they revel in scolding other red squirrels.
A red squirrel, seething with indignation, has a veritable arsenal of squirrelish invective to hurl at an intruder. In fact, these little squirrels have raised indignation to the level of high art! Chirks, squeaks, grunts, and other sounds too difficult to describe pour forth in incredible profusion from that tiny body, accompanied all the while by jerks of the tail and shuffling and stamping of the hind feet. Some of these sounds—particularly a very high squeak and a low, raspy grunt—seem to be made simultaneously, although they may simply follow each other so rapidly as to give that illusion.
A red in the throes of one of these vituperative displays brings to mind a tiny teakettle as it boils over, hopping on the stove while bubbling and steaming furiously, or a miniature Vesuvius about to blow its top. Heard and seen at close range, this is a performance to be treasured! Because of this feisty behavior, incongruous in a creature so small, we affectionately refer to any red squirrel around our home as Big Red.
The personality difference between gray and red squirrels shows in another major way, too: wariness. To those who have encountered gray squirrels only around backyard feeders or as furry mendicants begging for food in urban parks, it may come as a surprise that completely wild gray squirrels are extremely wary.
When a gray squirrel sights a human in the wild, it either dashes into a handy den or conceals itself in the top of a tree. There it’s almost impossible to see, even after the autumn leaves have fallen. Even if the person then sits down and remains absolutely still, the squirrel usually won’t reappear for about twenty minutes. In rural areas, gray squirrels are widely hunted for their delicious meat, and any squirrel hunter can testify to the wariness of grays in the wild.
Red squirrels in the wild, on the other hand, are at least as apt to remain and roundly curse a human intruder as they are to hide. Even with the semi-tame squirrels around backyard feeders, some of the same behavioral differences are evident. For example, we have only to open our door and the gray squirrels flee precipitously, streaking for the nearby trees. The feisty little reds, however, will stay, sometimes even when approached within two or three feet, and hurl insults at us like an angry fishwife whose toes have just been stepped on.
Another amusing trait is the red squirrels’ penchant for closely pursuing each other. A common sight in the woods is to see one red squirrel racing after another at top speed across the ground, then chasing it around and around a tree trunk in a sharp upward spiral. At some point the whole affair is reversed, and the two spiral down the tree and speed away out of sight. All the while, the two squirrels will maintain the same distance of a foot or two from each other, so perfectly synchronized that their capers resemble the operation of some mechanized toy.
Living accommodations for the two species differ greatly. Though both like tree dens, the grays are also great summer nest builders. The presence of gray squirrels is often revealed by these great, rounded bunches of leaves and twigs, sometimes several to a tree. Such nests, called
dreys,
are usually placed away from the trunk, where the juncture of two or more branches makes a convenient platform. Dreys are constructed so as to shed water. They’re hollow, with an entrance hole, and, like nests in tree cavities, are lined with whatever soft materials are available.
Grays tend to utilize several tree cavities—sometimes as many as seven— if they’re available, but usually they have both dens and dreys. Once the young have been born, the mother will frequently move them from one den or nest to another.
This may be partly a defensive strategy, making it more difficult for predators to dine on baby squirrel. Biologists also speculate, however, that it may be a way of avoiding the major flea infestations—sometimes thousands in a den—that regularly plague squirrels. Indeed, one squirrel biologist who sported a full beard was finally forced to shave it off because so many squirrel fleas hopped into it!
Red squirrels also den in tree cavities; when these are lacking, they’ll build dreys, though in much smaller numbers than the grays. However, the reds are just as apt to den in a burrow in the ground, often dug between the roots of a tree or under their food cache. When they do build nests, these are placed close to the trunk of a tree and are much smaller and less conspicuous than the nests of the grays. Usually the red’s nest is constructed of twigs, or twigs mixed with shredded bark, with far fewer leaves than the gray’s leafy bower.
Red squirrels remain highly active most of the time during the winter, though they may sometimes hole up for a day or two in exceptionally stormy or bitter weather. They are always solitary in the winter, and may den in a tree cavity, in a burrow, or simply in tunnels in the snow.
Reds also like to expropriate birdhouses for a den. While cleaning out our bluebird houses one spring, I failed to pay sufficient attention to the fact that the house was full of various soft plant materials. As I dug down into the mass, I was startled to feel movement and hear an angry squabbling sound. At the first glimpse of red fur, I realized that I had wrecked the happy winter home of a red squirrel, which was now decidedly indignant!
Gray squirrels also remain active throughout the winter, although they may be semi-dormant for a couple of days during unusually inclement weather. Unlike the solitary reds, grays also den communally. These dens are shared by males and juveniles, which are very sociable and may groom each other. Breeding females, on the other hand, are cantankerous and den by themselves. Gray squirrels in the more northern parts of their range normally have one litter a year. Farther south, two litters a year is common. Breeding for the first litter is in January and February, with May and June the usual breeding time if there’s to be a second litter. The young are born blind and naked, usually two or three to a litter, although there may occasionally be as many as five.
Red squirrels have somewhat larger litters, usually four or five, but sometimes as many as seven. They, too, sometimes bear two litters a year, although one is more common.
If humans handle young squirrels in their den, the mother’s exceptionally keen sense of smell detects it. However, rather than abandoning her brood, she immediately moves her young to another den as a precautionary measure.
As this behavior indicates, squirrels of both species are extremely good mothers. Despite the care that they lavish on their broods, however, life is apt to be brief and hard for squirrels in the wild—juveniles and adults alike. Eighty percent of young squirrels die during their first year, and adults seldom live more than three or four years.
One major reason for such a high mortality rate is predation, for many hungry creatures are perfectly happy to dine on squirrel. Foxes, coyotes, and bobcats sometimes catch an unwary squirrel on the ground, but members of the weasel family are a much greater threat to tree squirrels (see chapter 14). Although weasels themselves spend most of their time on the ground, they can climb trees to get into squirrel dens, and these slender little predators can easily slip into any hole or burrow that a red squirrel can enter. Two larger weasel cousins, the marten and the fisher—especially the former—can also pursue and capture squirrels in the treetops.
Hawks and owls also take a heavy toll of squirrels, and I received a striking demonstration of that fact within a few feet of our house. I had just opened the door and stepped out, when a movement caught my eye. No more than fifteen feet away, a hawk—either a small Cooper’s hawk or a large sharp-shinned—had just seized Big Red (actually one of our many Big Reds) in its talons and was bearing it away toward the nearby woods. And although barred owls, at least, seem generally to prefer mice to squirrels (see chapter 11), a fellow naturalist told me of watching a barred owl in the forest seize a red squirrel.
