Biology Reference
In-Depth Information
tainly the hole was the entrance to its den. Where it had come from or what it had been doing is any-
one's guess.
On another bright, sunny day, two of us were doing forestry work. As we sat on the ground that
noon, munching our sandwiches, my companion suddenly whispered, “Look, there's a flying squirrel
coming toward us.”
Sure enough, a flying squirrel on the ground was headed in our direction; its movements, impeded
somewhat by the skin flaps, were far less graceful than the glides normally associated with its species.
There was a small clearing in front of us, with mushrooms growing here and there, and these fungi were
an evident attraction for the little squirrel. While we watched, it eagerly ate parts of several mushrooms,
gradually drawing closer to us.
Paul Fiske, my partner, had a pair of leather work gloves which he had laid on the ground beside
him. Slowly and quietly slipping them on, he whispered, “I'm going to try to catch it.”
Moving with great caution, Paul got to his feet; then he leaped up and ran at full speed toward the
squirrel. With nothing close by to climb, the squirrel could only run for the nearest tree. Hampered by
its skin flaps, the squirrel was a slow runner, and Paul scooped it up after a few long strides. I ran to
join him, and together we inspected the soft, big-eyed creature that Paul was holding very gently. After
we had satisfied our curiosity, the squirrel was placed on the ground and released, whereupon it ran to
the nearest tree, climbed it, and glided off into the forest.
Unquestionably, flying squirrels are predominantly nocturnal. Because I've seen them abroad twice
in full daylight, however, it's evident that these furry gliders are more diurnal than is generally believed.
After all, my two daylight encounters with them can hardly be unique, and no doubt many other people
have occasionally observed flying squirrels active in the daytime.
There are two species of flying squirrels native to North America, the northern flying squirrel
(Glaucomys sabrinus)
and the southern flying squirrel
(Glaucomys volans),
as well as some subspecies.
Although these two species are somewhat different in size and in some of their habits, they're very sim-
ilar in at least three characteristics.
First, the eyes are large, very dark, and prominent—hence the genus name of
Glaucomys.
This name
ultimately stems from the Greek word
glaukos,
meaning bluish gray, probably because of the way the
flying squirrel's eyes reflect light. Second, both species have wonderfully fine, soft fur, far softer than
the fur of their tree squirrel relatives, such as the red and the gray. And third, of course, both species
glide whenever possible, and are much more at home in the trees than on the ground.
Despite these major similarities, there are a few noteworthy differences between the two species.
Size is one. The northern flying squirrel can have a total length of as much as thirteen inches, although
eleven inches or so would be more typical. Of this, the tail takes up roughly four to five inches, while
the remainder is head and body. In total length, then, the northern flying squirrel is only about an inch
shorter than the red squirrel, although it appears considerably smaller. That's because the red is stockier
