Take Me Outside: The secret lives of squirrels

At this time of year many people enjoy feeding birds. Inevitably if you put up bird feeders, you’ll also end up feeding squirrels. While this can be frustrating, rather than spending energy and funds on “squirrel proofing” a feeding station, why not give-in to squirrel tenacity and enjoy some of the marvels of these tree rodents.

In this part of the country we have five resident squirrel species. Chipmunks, our only ground squirrel, are dormant in underground burrows at this time of year. Two species of flying squirrels are nocturnal and rarely seen. The common tree squirrels include the eastern gray squirrel and the smaller red squirrel. Both are arboreal and extremely adept at tree climbing (and bird feeder jumping).

Beyond that, they have surprisingly different habits.

Gray squirrels eat acorns, hickory nuts, beechnuts, butternuts and walnuts. As a result their preferred habitat is a forest with nut-bearing trees. Red squirrels will eat nuts if they find them, but more commonly feed on seeds from conifers, such as pine, spruce, fir and hemlock. Thus forests dominated by evergreens are where red squirrels are typically found.

How the two species gather, store and consume their fare is also distinctive. Upon finding a nut, if it is not eaten immediately, the gray squirrel will bury it, marking the spot with its scent. Later, perhaps during the winter when the location is concealed beneath snow, the squirrel may use its sense of smell to find it, dig it up and eat it. Or it may not. Another squirrel might have found it first. Yet, many nuts are never found and thus squirrels inadvertently become tree planters, ensuring a food source for future squirrel generations.

Red squirrels employ a different strategy. They cache their food in a hollow tree or underground, sometimes accumulating bushels of intact pine cones all in one place. When retrieving the cones, they bring them to a feeding stump or log and nibble on a cone the way we might munch on corn on the cob. A midden or large pile of cone scales and cores left on a stump is a sure sign of a red squirrel dinner table.

Both squirrels also feed on softer plant material. Berries and tree buds comprise part of their diet during warmer weather. A wild apple found in the crotch of a tree or a mushroom speared onto a branch to dry are clues that a squirrel is trying to vary its diet.

Surprisingly, these rodents are not exclusively vegetarians. Both are known to eat birds’ eggs and baby birds. Gray squirrels will eat insects, caterpillars and even woodland frogs. Red squirrels may consume smaller mammals, such as mice or voles.

On the flip side of the consumption equation, squirrels are eaten by many larger animals such as foxes, coyotes, bobcats, fishers and birds of prey. Because of this they are wary and have amazing survival skills.

One of their best defenses is climbing a tree and leaping from branch to branch with the precision of a circus performer. What seems like a random romp to us, is actually a carefully chosen route. Squirrels lay out and follow (probably by scent) familiar pathways through the branches. This gives them a distinct advantage of knowing where to go in a hurry.

Familiarity with territory is another key to survival. Red squirrels are extremely defensive of their home range, including food caches and dens.

They use a wide variety of vocalizations, tail waving and foot stomping to let intruders know they are not welcome. Gray squirrels are less particular, are known to den communally in the winter (males and juveniles) and have overlapping home ranges. Only when the female has young in a nest does she defend her space.

When there are conflicts, they usually only involve a friendly chase, avoiding any real aggression.

Chases can be observed during the February breeding season.

If you see a train of gray squirrels scampering across the ground, up and around a tree trunk, it is likely a female being pursued by one or more males, hoping to pass on their genes.

If one of them is successful, in about six weeks there will be a new generation of squirrels to observe and learn from as they share our “bird” feeders.