Is there a creature in the watershed that you’d like to know more about? Send us an email if you’d like to suggest an animal for a future “Creature Feature” page. Emails should be sent to sbrookman (at) urwa (dot) org. We also welcome digital photos of animals and scenes within the watershed!

CREATURE FEATURE

Flying Squirrel
When you hear the term, flying squirrel, do you immediately think of Rocky and Bullwinkle, the loveable cartoon duo from the 1960s who delighted children and adults alike with their zany antics? For many, Rocky is our only frame of reference for flying squirrels, and although he entertained us, he didn’t teach us much about his counterparts in the wild. Fortunately for people living in the Upper Raritan watershed, flying squirrels don’t have to be relegated to the cartoon world – Northern and Southern flying squirrels live in forests across our region!

As their name suggests, flying squirrels differ from other squirrels because they don’t simply leap from tree to tree. Flying squirrels can launch themselves from high tree limbs and glide through the air, covering as much as 50 yards in a single flight! These squirrels have a fold of skin on each side of their bodies that extends from the wrist of their front leg to the ankle of their hind leg. When their front and hind legs are extended, this fold of skin, (known as a gliding membrane, or patagium) forms a wing-like gliding surface. Flying squirrels have furred, broad, horizontally flattened tails that serve as a rudder and stabilizer during glides.

Another difference between flying squirrels and other squirrels is the fact that flying squirrels are nocturnal. Their eyes are noticeably larger than those of other squirrels, an adaptation that allows them to see in the dark. It is thought that their nocturnal nature evolved to protect them from predators such as hawks, which would be likely to see them gliding through the air if they were active during daylight hours.

Both northern and southern flying squirrels have thick brownish fur. The northern flying squirrel, which can reach 12 inches in length, is slightly larger than its southern cousin. In New Jersey, southern flying squirrels are common throughout the state’s forests, but northern flying squirrels live here only on the highest peaks in the cool spruce/fir forest zone. Both species live in dens (typically in abandoned woodpecker nests and hollows) in the winter and through the birth of their young, and in nests in the summer. They feed on a diet of nuts. Seeds, berries, insects, mice and small bird eggs.

Seeing a flying squirrel gliding is a real treat! Before it takes off from a treetop perch, the flying squirrel assesses its landing site by moving its head up and down and from side to side, apparently triangulating to judge distance. It then launches itself with all of its legs extended at right angles from its body, and this is when its patagium is visible. Flying squirrels are agile, and can steer around branches of trees in its path by using their tails as rudders, and they also steer themselves and control their speed by changing the tension in the patagiums. They usually land upright on the trunk of a tree and quickly move to the opposite side of it to evade any predators that might have spotted them in flight.

For more information about damselflies and dragonflies, please visit these links:

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