Glaucomys – New World flying squirrels

A fascinating group of rodents, better known as the flying squirrels of North America. This genus contains three species: the southern flying squirrel (Glaucomys volans), the northern flying squirrel (Glaucomys sabrinus), and the recently recognized Humboldt’s flying squirrel (Glaucomys oregonensis). All three share a distinctive feature—a skin membrane called the patagium, which stretches from their wrists to their ankles. This membrane acts like a parachute, allowing them to glide gracefully from tree to tree, sometimes covering distances of over 150 feet in a single leap.

What makes Glaucomys especially unique is not just their ability to glide, but how well-adapted they are for their nighttime lifestyle. They have large, dark eyes that give them excellent night vision, perfect for spotting insects, nuts, and seeds in the dark forest. Their tails are long and fluffy, serving as rudders that help them steer mid-air and balance on branches. Unlike many other squirrels that rely heavily on daytime activity, flying squirrels are strictly nocturnal, which makes them much less likely to be spotted by casual observers—even though they may be abundant in forests.

In terms of behavior, these squirrels are surprisingly social. Southern flying squirrels, for instance, are known to gather in communal dens during colder months, sometimes with dozens of individuals huddled together for warmth. Their diets are also more varied than most tree squirrels. In addition to nuts and fruits, they often feed on fungi and even insects, playing an important role in spreading fungal spores that help trees absorb nutrients. The northern flying squirrel, in particular, has a close ecological relationship with mycorrhizal fungi, making it a key player in forest health.