NATURE NOTES FROM ACADIA

THE NORTHERN FLYING SQUIRREL

(Number 1 of a series of articles about the fur bearing animals of Acadia National Park)

The sunset colors faded from the western sky and the winter night settled over the snowy woodlands. Quiet reigned. The heavy snow-burdens which rested upon and weighed down the conifers, the dominant trees of our Acadian forest, acted the part of so many padded sound-absorbing curtains, thereby itensifying the stillness which pervaded this wintry grove. Already the full moon shone brightly over a cold world clad in ermine.

Quiet it was, but in the hollowed heart of the limbless old beech which leans over the frozen woodland brook like a spar buoy leans on the sea, life was stirring. At one of the woodpecker-drilled openings a small rounded head with large dark eyes put in its appearance, and soon the animal, the flying squirrel of our northern forests, emerged and commenced its nocturnal goings and comings. Rather clumsily it made its way to the top of the old beech and from this point launched out into space on a glide which took it perhaps 15 feet to the lower part of a slim straight spruce. Upon landing, another ascent and another glide took it well out of sight.

Knowing the secret which it holds, let us return to the beech during the daylight hours. There is no stir now, not even when one's ear is placed close to the dead lead-colored bark is there any sound. Seizing a short stout piece of a dead tree limb I commence to pound the shell of the old tree vigorously when, after the fourth or fifth blow our flying squirrel appears at the opening. Something is amiss! This is indeed a rude awakening, but it is the only way which enables us to become better acquainted with one of the most beautiful creatures of the forest. Hurrying to the upper reaches of the tree the squirrel stops as though to deliberate upon the course to follow, and in the meantime two more and finally a third make their way out of the same hole. All of them seem loathe to leave their nest, for it is probably true that no squirrels are more attached to their homes than this one. Backing slowly away from the fruitful beech I am enabled to observe the animals at close range with my binoculars.

Large dark eyes, a flattened appearance to the body, broad lateral skin folds which extend from the fore- to the hind legs, a well-haired flattened tail, and the softest kind of a silky coat - these characterize our Northern Flying Squirrel (Glaucomys sabrinus macrotis). Above its fur is a buffy-gray except for the regions of the nose and eyes, the tail, and the upper part of its feet which are a kind of smoky gray in color. The underparts are a soiled white. In total length the adult animal measures approximately 11 inches of which about 5 inches is tail. Its cousin the flying squirrel of the south (Glaucomys volans) is smaller while its closer relatives to the north are somewhat larger in size.

This fur-bearer is not a flyer in the true sense of the word. Like the flying lemur of the East Indies this arboreal squirrel progresses to large extent by gliding from tree to tree; on the ground it is the most hepless of our squirrels. Its gliding membranes and flattened body enable it to sail for a considerable number of feet through the air; in Ohio I have watched one of these creatures (G. volans volans) volplane from the upper part of one tree to another 42 feet away, and there are reports of individuals which have been observed travelling two and three times that distance. It goes without saying that the animal always lands at a point some distance below that from which it begins the glide. (Of all our fur-bearers, only the bats are capable of true flight).

As already stated, flying squirrels are active only at night. In certain wooded areas these mammals may be fairly common, but, due to their nocturnal habits, are rarely if over soon.

To a large extent they are vegetarians, but are known to eat flesh and insects. Frequently they spring the traps intended for larger game. Dr. Vernon Bailey, recently retired from the U. S. Biological Survey, writes that some trappers have reported dozens and others hundreds of flying squirrels caught on their winter's trapline in the region near Glacier National Park. Early last September Dr. A. E, Brower, Entomologist for the Maine Forest Service, caught two of these animals near his laboratory at Bar Harbor; his traps were baited with moths.

Three of these squirrels have been brought in since the taking of Dr. Brower's specimens: one which was severel y injured on Octobor 5 when a CCC crew felled a dead tree south of the Tarn; another was presented to me on January 3, 1935, by a lady who found it in a weakened condition in a street in Bar Harbor; the third, with both its hind legs broken, was found dead on January 19, 1935, by another crew of CCC boys in the spruce woods near the Tarn. On August 31, 1932, I picked up a dead flying squirrel which lay beside the road near the Mount Desert Nurseries; apparently it had been struck by a passing car. Various CCC crews working in Acadia National Park have reported seeing these animals after disturbing the trees in which the squirrels spend the daylight hours.

Seton¹ says of this fur-bearer, "It is so nearly dependcnt on the woodpeckers for its tenement quarters that it will not be found where no woodpeckers are." The usual nest is such a one as has been described - in a hollowed, woodpecker-drilled tree. Outside nests of the Gray and the Red Squirrels are well known, and there are instances of the Southern Flying Squirrel occupying such a nest on rare occasions, but Seton writes,² "So far as recorded, the Northern Flying-squirrel does not make a dray or outside nest." Since various other authorities either agree with Seton or make no mention of the use of an outside nest by the species in question, I wish to record the finding of such a nest in Acadia National Park on December 19, 1934. The facts are as follows:

Two CCC supervisors, Mr. Lunt and Mr. Pinkham, working in a wooded region one-half mile south of the Tarn, came upon the outside nest that morning when their men disturbed the squirrels by felling a birch hwhich grew close to the tree wherein the nest was saddled. Four flying squirrels which occupied the nest emerged, three of their number returning to it soon afterward. That afternoon I went to see the nest. It was about 20 feet from the ground in a small red spruce, and from it we frightened a lone flying squirrel. The animal took refuge in a maple whose arms extended above the nest-tree and there, head downward, it watched us for some time. Finally, when Mr. Lunt climbed into the spruce to collect the nest, the squirrel planed to a nearby tree and from there to a large arbor vitae whose outer bark had been stripped from it almost to the very top.

In shape the nest might be described as a flattened sphere whose greatest diameter was 10 or 11 inches. It appeared to be freshly made, consisting mostly of the bark of arbor vitae which, in the interior, wqs finely shredded. A few small pieces of the common gray-green Usnea lichen were incorporated within the structure. Slender spruce twigs were interlocked to form a kind of flimsy exterior about the entire affair. It had but one entrance. Lice proved to be numerous within.

Mr. Walter J. Clayton, taxidermist and naturalist living in Lincoln, Maine, tells me that he has seen a few outside nests of our Northern Flying Squirrel in his rambles in the forests of north-central Maine, his description of these being almost identical to the nest I have recorded. However I have yet to see a published account of similar observations.

Seton,³ commenting upon the fact that this squirrel is both sociable and gregarious, writes of finding nine adults living in one stub, while Witmer Stone and W. E. Cram⁴ state that "a dozen or more of them will occupy the same hollow tree and I have heard of as many as forty being driven from the same hole."

Occasionally these squirrels will nest in deserted or little-used buildings and in bird boxes. In late May, 1933, Mr. Clarence E. Dow, manager of the Mount Desert Nurseries, presented me with a female and three young of this species which had their nest in a dresser drawer in an unused bedroom of Mr. Dow's house. All that summer these youngsters amused our visitors, and in early September they were taken to the woods and liberated. Mrs. J. Franklin Anthony of Great Head tells me that these nocturnal animals frequently stuff her bird boxes with nesting material and also take great liberty with the seed which she supplies to her bird feeding stations. Every summer since 1921 a few flying squirrels pay frequent visits to the porch of the summer residence of the Misses Bodine and Lewis, next door to the Asticou Inn, at Northeast Harbor. Apparently well aware that they can rely on both food and safety here, they come and go and sometimes allow even the guests of the two kind ladies to feed them from the hand. Miss Bodine, an expert wildlife photographer, has taken a series of excellent movies of these attractive large-eyed subjects.

Flying squirrels remain active the year around. Their enemies, aside from man, include cats, owls (rare on Mount Desert Island), and, on rare occasions, foxes, minks and weasels.

-Arthur Stupka