How a flying squirrel glides
A northern flying squirrel launches from a trunk, spreads its limbs, and stretches a loose membrane into an airfoil. Its flattened tail works as a rudder and brake. Just before landing, the squirrel turns upward, loses speed, and grips the next trunk feet-first.
It can’t gain height or flap like a bat. Each trip trades height for distance, so tall trees and connected crowns make travel easier. Gliding lets the squirrel cross gaps quickly while spending less time on the ground, where many predators hunt.
Large dark eyes suit life after sunset. Soft gray-brown fur covers the back, while the underside is pale at the tips but darker near the roots. That dark-based belly fur helps distinguish it from the generally smaller southern flying squirrel where both occur.
A forest linked by fungi
Cool conifer and mixed forests form the heart of its range. Northern flying squirrels use tree cavities, old woodpecker holes, and leafy nests for shelter. They need more than large living trees: dead wood, decaying logs, and a varied forest floor also support their food.
Fungi are especially important. The squirrels eat mushrooms and underground fungi, then spread spores in their droppings. Those fungi help tree roots gather water and nutrients. The squirrel therefore links the forest floor with the canopy in a partnership that isn’t obvious from a nighttime glimpse.
Seeds, buds, fruit, lichens, and occasional animal matter broaden the diet. Food changes with place and season. Cached items and many small feeding trips help the squirrel remain active during cold periods rather than entering a long winter sleep.
Nights in the canopy
These squirrels usually leave shelter after dark and move through familiar routes among trees. Records occur in every month, which fits year-round activity. Reporting volume still reflects observer access and effort, so it doesn’t show how many squirrels occupy each region.
Individuals may share nests, especially in cold weather. Huddling reduces heat loss, while several nest sites provide alternatives when parasites, predators, or disturbance make one cavity unsuitable. Females use sheltered nests to raise small litters of blind, lightly furred young.
Owls are major hunters, and forest mammals can catch squirrels at nests or on the ground. A glide offers speed but not safety everywhere. Landing trunks and den cavities become predictable places for an ambush.
One name across separated forests
The national record pattern isn’t continuous. Broad northern populations occupy Alaska, the Pacific Northwest, the northern Rockies, Great Lakes forests, and the Northeast. Other groups persist in high mountain forests separated by warmer or drier country.
Logging, severe fire, development, and forest fragmentation can remove den trees or break canopy routes. Effects vary across the wide range, and the species remains listed as Least Concern overall. Isolated mountain populations can face much tighter limits than that broad rating suggests, especially where cool forest retreats upslope.
