Those Clumps Of Leaves and Sticks Aren’t Birds Nests Left In Michigan Trees
I could have sworn my entire life, when I looked up into the trees in the winter - after all the leaves had fallen - I was seeing leftover bird nests between the branches. And it makes sense. Once the birds are hatched and grown, they spread their wings, and fly outta here, leaving the nests behind.
But it turns out, those clumps of leaves and sticks in the trees are NOT birds nests, and not at all what I expected.
Those clumps of leaves and sticks between the branches are what's called a "drey," or basically, a squirrel nest. When knots and holes aren't available in the trees, squirrels will take after the birds, and collect items to insulate themselves.
Some trees can have up to a half-dozen dreys in them, depending on how dense the squirrel population is in your area. Behind my apartment complex, there's at least a dozen in all of the trees.
But interestingly enough, the dreys you're seeing in the trees now, are likely empty. Yes, you'll see squirrels running around still, but according to various Audubon Societies, the dreys are actually summer homes for the squirrels to collect their winter loot of acorns and nuts, and where they raise their young.
And just like birds, when the young are grown, they flee the nest. Some squirrels will use existing dreys for shelter during the winter months, but more often than not, they prefer existing holes and natural cubby spots to stay warm in the winter.
So now that this is solved, I have one more question.... where are all the empty bird nests?