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Nature Notes: Little Red Rocket

Ed Robinson
November 20, 2018

In the autumn I spend a lot of time perched in trees. Deer hunting is mostly a good excuse for watching and listening to the sights and sounds of nature. As I approach a tree stand, the forest around me goes silent. If I remain still, things return to normal within a few minutes and the creatures of the forest will go on about the business of gathering food in preparation for winter. Unless there is a nearby red squirrel with an attitude.

I have a bit of a love/hate relationship with American red squirrels, sometimes called “chickarees.” On one hand, it’s easy to admire an energy-packed little fellow who can survive with so many predators looking to make a meal of him. On the other hand, red squirrels seem to delight in giving away my presence in the woods with all their chirping and buzzing. They are like little emergency warning systems broadcasting that all is not right within their sector of the forest. On several occasions I have had pine cones dropped on my head, as if the squirrel was saying, “C’mon big guy, you want a piece of me?” That’s okay, I get it, and I always look forward to seeing them, if only because most of my deer hunting involves interminable hours on the stand with only my thoughts and my “Honey Do” list to occupy me.

The red squirrel (Tamiasciurus hudsonicus) was first documented in the late 1700s by European visitors to Hudson Bay, Canada. Today they occupy a big swath of the northern US and southern Canada, since they thrive where conifers exist in large numbers. Out of more than 200 different species of squirrels, red squirrels are lumped in the same category of pine squirrels as two others in North America: the Douglas squirrel of the Pacific Northwest and the endangered Mearn’s squirrel of Baja Mexico. The red is a distant cousin of flying squirrels and the much larger Eastern grey squirrel. In England, the Eurasian red squirrel population has dropped considerably because of imported grey squirrels and a poxvirus they carried, which is fatal to the reds. While squirrel poxviruses exist in the wild here, a report from Michigan’s Department of Natural Resources noted that the viruses have only minimal effects on our squirrel population.

Somewhat larger than chipmunks, red squirrels are handsome creatures. Their backs are often a reddish brown, while their bellies are white. The head and lower legs show touches of grey and their bright, black eyes are ringed in white. Tails vary in color from reddish brown to yellowish grey, often tipped in yellow or white. As their winter coats grow in, the ears become slightly tufted. An adult measures roughly fourteen inches long with the tail and weighs less than half a pound, with the male slightly larger than the identically colored female.

Like other small mammals in a competitive world, red squirrels spend much of their time on the move, especially in autumn, trying to find food for the day and the winter ahead while keeping safe. More than half their diet will be high energy seeds and nuts when they are available. Over the course of a year the squirrel will also eat flowers, leaves, buds, fruit, mushrooms and insects. They have been observed eating bird eggs plus juvenile birds and rodents, but I suspect this is more opportunistic than planned. The squirrels may have a negative impact on small stands of conifers by eating the majority of seeds produced, and because they often strip the outer bark to get at the underlying cambium layer. In partial compensation their buried nuts and seeds may become a source for new tree growth.

Red squirrels often act like they have a chip on their shoulders, showing aggression to large and small creatures in their space, birds and mammals alike. Males and females have their own territories and will defend them against encroachment. This territorial behavior is intended to shelter their young and to protect their food supplies stored in multiple large caches known as “middens.” Scientists have documented huge stores of pine cones and nuts stored underground or in hollow trees, up to eighteen thousand items in total. When threatened, the red squirrel knows her home territory intimately and will generally use flight rather than fight. But from a safe perch she will bark, screech, buzz and even growl to show her displeasure at being disturbed. These calls also serve to alert other creatures in the area.

The mating habits of red squirrels would make a maiden blush. Mature at one to two years, the female enters estrous for only one day in late March or April so the timing of mating is critical if she is to extend her gene pool. In the days before ovulation the squirrel will enter the neighboring territories of males to alert them to the hormonal changes that will make her receptive to them. When the big day arrives it is common to see several males chasing the female, with repeated tussles to see which male gets the first chance to mate. But one mate is not enough – she may allow a dozen or more males to mate with her, perhaps to ensure that at least one has the vigorous seed necessary for her to bear young.

After all of that excitement, males have no role to play in rearing the young. The female prepares multiple nests of twigs, grass and leaves in tall trees or rarely, in underground burrows. She prefers dens in hollow trees for comfort and safety. Gestation takes place over four or five weeks, then the female gives birth to between two and five tiny hairless pups. While the pups leave the birth nest after six weeks, the female allows them to nurse for two months or longer and may move them among her nests or dens while staying near her food supplies.

The juvenile squirrels reach adult size within four months and are soon pushed out to find a territory and food supplies of their own. In some cases the mother will yield a part of her own territory if food supplies are abundant. Otherwise the young squirrels branch out into an unoccupied territory or fight for one. Then the race is on to build a stock of food before winter arrives. Red squirrels do not hibernate, their bodies are too small to build the necessary layers of fat to withstand deep freezes, and their metabolisms too robust to go without food for months. While they may rest for a day or two in bad weather, the squirrels eat regularly during winter as they try to keep their body temperatures above freezing.

It is a harsh world for the squirrels, with many predators hoping to feast upon them. Studies show that fewer than 25 percent of red squirrels survive their first year, and the average life span in the wild is estimated at three to four years. Hawks, owls, crows, fox, coyotes, bobcats, martens and weasels will take every squirrel that makes a mistake within reach. While fleeing, squirrels can run like the wind on the ground, darting left and right, but it’s aloft where they amaze by rocketing up and down tree trunks, jumping from one tiny branch to another as if there was no risk of falling. If they escape death the squirrels are less likely to hide than to take a safe perch and then give their pursuer a loud blast of squirrel indignation. Tenacious little balls of fight, those red squirrels, you almost have to admire them, almost…

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