What The Heck Are These Things In North Dakota Trees?

You may not have noticed those big, round piles of leaves up in the trees until fall and even into winter. They don't look like bird nests, so what are they?

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While only one is observed occupying multiple large branches in one tree, others may have several dispersed throughout the same tree. However, they are everywhere.

Most likely, what you're seeing is what's known as a drey, which houses your friendly neighborhood squirrel all year round.

Dreys are up in the trees year-round, but during the warmer months, when everything is vibrant and in bloom, they are obscured by leaves.

Our dogs enjoy barking at and chasing those outdoor, furry creatures in those dreys. Indeed, squirrels build much larger nests than birds do, and they do not limit their habitat to inside trees.Since those are squirrels' summer residences, they are probably empty in the winter. That's where they vanish when they dash up trees in search of acorns or simply drop their inquisitive squirrel objects on the ground. But if they are unable to locate a tree cavity to spend the winter in, they will live in dreys.

Actually, if you notice a lot of acorns gathered in one spot near a tree, there's probably a squirrel drey above you. The drey might have begun as a bird's nest before a family of squirrels moved in and expanded it with more leaves and twigs.

In the winter, squirrels spend less time foraging outside their dens, and it’s more common for several squirrels to share a den. This behavior allows more animals to take shelter and to keep each other warm.

Squirrels also prepare for winter by bulking up. Throughout the fall, they maximize food consumption and body mass. In winter, when food is hard to come by, these reserves will help the animals survive.

One other tactic gray squirrels use to keep warm in winter is shivering. Shivering isn’t just a sign that you’re cold; it also serves as a way to keep warm. While it certainly doesn’t sound fun, gray squirrels are remarkably good at generating heat by shivering.