Ever spot a squirrel drey way up in a tree and wonder how on earth they built it so neatly out of twigs, leaves, and moss? Squirrels actually weave a tough outer shell from twigs, then tuck soft leaves, grass, and sometimes fur inside to keep warm and dry.
As you read on, you’ll see how squirrels pick out their building materials, choose the best branches or tree cavities, and patch up nests after rough weather. We’ll break down how they build, what makes dreys and dens different, and where squirrels actually prefer to set up their homes.
How Squirrels Build Their Nests
Squirrels pick safe, high spots and use whatever they can find around the tree. They shape a sturdy outer shell, choose materials carefully, and make a cozy inner chamber for resting or raising babies.
Nest Construction Process
First, squirrels choose a fork or thick branch 20–60 feet up. You might catch them gathering twigs and testing which branches hold their weight.
They bend flexible twigs into a rough sphere and wedge the base into the fork, making sure the nest stays put. The outer shell comes first, built from the bottom up.
Watch a squirrel run back and forth—one can make dozens of trips to collect the right stuff. Depending on weather and how easy it is to find materials, building the nest can take anywhere from a couple days to a week.
After storms, squirrels get busy with repairs. You might notice fresh twigs or leaves added to the outside. This constant maintenance helps the nest last through bad weather and keeps it ready for babies or shelter.
Materials Used in Nests
Twigs and leaves make up most of a drey. Squirrels use thick twigs for the main frame and weave in thinner, bendy ones to create a kind of lattice.
Leaves get layered both around and inside the frame. They also add moss, strips of bark, grass, and sometimes fur or even feathers.
Each thing has its purpose—moss and fur bring warmth, bark gives strength, and grass fills in the gaps. Squirrels always go for dry materials to avoid mold and keep things light.
You’ll see different mixes depending on the squirrel and spot. Tree cavities usually get more fur and less leaf layering, while above-ground dreys need lots of twigs and leaves for both structure and camouflage.
Twig Framework and Leaf Layering
The twig framework acts as the skeleton of the nest. Imagine a crisscross of twigs forming a ball shape.
Squirrels weave the twigs tightly so wind and rain can’t tear the nest apart. After the framework is done, they start layering dry leaves into the outer weave and pack more leaves inside.
This leaf layer blocks cold and wind, and also helps the drey blend in up in the canopy. Sometimes, squirrels add mud or lichen to glue everything together.
The entrance is usually a small hole on the side, facing away from the wind. That keeps drafts out and helps the inside stay dry.
Insulation and Inner Chambers
Inside, squirrels line the chamber with softer stuff you probably wouldn’t notice from the ground. They use fur, shredded bark, grasses, and moss to make a padded cup for sleeping or raising babies.
This lining traps heat and keeps the chamber round and snug. Squirrels put the entrance in a spot that loses the least heat.
Mother squirrels spend a lot of time inside with their babies, keeping them warm until their eyes open. When squirrels find tree cavities, they use them as dens with deeper, more protected chambers.
Cavity dens don’t need as much leaf insulation, but squirrels still add soft lining for the young. Both dreys and dens get carefully insulated, depending on what the local weather throws at them.
Types and Locations of Squirrel Nests
You’ll spot squirrel nests in high tree forks, inside hollow trunks, underground, and sometimes even tucked away in man-made boxes or building gaps. Each nest type serves a purpose—shelter, raising young, or hiding food.
Dreys: Leaf Nests in Trees
Dreys are those round leaf nests you see wedged in big branch forks, usually 20–60 feet above the ground. Squirrels weave twigs into a shell, then line it with leaves, moss, and shredded bark to make a dry, insulated chamber about 6–8 inches wide.
Dreys keep out rain and wind, but strong storms can still be a problem. You’ll often see a few dreys scattered in a squirrel’s territory.
Mothers use these nests for raising babies in spring and summer—they’re quick to build and easy to patch up. Look for chewed pine cones, little twig piles, or leaf bits under a drey.
Gray and red squirrels both use dreys, but flying squirrels usually pick tree cavities instead of building big leaf nests.
Cavity Nests and Dens
Cavity nests hide inside hollow trunks or old woodpecker holes. These dens offer way better protection from predators and nasty weather than a drey.
You’ll see cavity nests at all sorts of heights, from low branches to way up in the tree, depending on what’s available. Ground squirrels dig burrow dens with tunnels and sleeping chambers.
Squirrel families reuse cavity dens, and sometimes other wildlife moves in later. If you spot a neat pile of wood chips at the base of a tree, that’s a good sign of recent cavity work.
Cavity nests are the top pick for raising babies—they hold heat and keep pups hidden from hawks and owls. Flying squirrels and most tree squirrels go for cavities if they can find one, though gray squirrels sometimes use them too.
Squirrel Nest Box and Urban Nesting
If you want to help out tree squirrels, you can put up a nest box for them. Mount it 10–20 feet high, facing away from the wind, with an entrance hole about 3–4 inches wide.
Use untreated wood and drill some ventilation holes near the top. In towns, squirrels often sneak into attics, soffits, or building gaps to make dens.
These urban nests work kind of like tree cavities but can cause noise or even damage. If squirrels move into your place, you’ll probably hear scratching or find nesting stuff like leaves and shredded paper.
A well-placed nest box can keep squirrels from moving into your walls. If you manage a property in town, check local rules before disturbing nests, especially if there might be babies inside.
Species Differences in Nesting
Different squirrel species go for different nest styles. Gray squirrels usually build dreys, but if they find a good cavity, they’ll use that too.
Red squirrels tend to make stick-and-leaf dreys higher up in conifers. They’ll even defend a few small dreys scattered around their territory.
Flying squirrels like sealed cavities or nest boxes lined with something soft. Since they’re nocturnal, they really need secure, dark retreats for their small families.
Ground squirrels dig out complex burrow systems. They create separate chambers—one for nesting, another for storing food.
If you spot nesting behavior, try to note the species, nest height, and what materials they’re using. That little bit of info helps you figure out if you’re looking at a drey, a cavity den, or maybe even an urban squirrel nest.
