Most people recognize a squirrel nest, called a drey, when they see one. The eastern gray squirrels in our region build dreys in trees for shelter and protection from the elements. What you see as a messy clump of leaves is actually a structure formed from sticks and then lined with leaves and other materials to make it a dry and cozy home.
This month I was walking around my neighborhood in Chicago, and I noticed that three out of four squirrel dreys on my street were located on branches that reach over the street. I had to ask myself why squirrels would build their homes in such a dangerous place. If the squirrel or its babies fell out, they would not only land on hard concrete but also risk being hit by a car! Are my neighborhood squirrels somehow related to the Three Little Pigs?
Since I know that is not the case, I started to speculate:
Perhaps squirrels are attracted to that particular view. Maybe thermal currents rising from the asphalt make that spot warmer than a branch over a lawn. Could it be that this spot also puts their predators at risk and therefore is actually a safer place to live? I don’t know!
So, I started looking around to see if there was a pattern in locations of squirrel dreys. To date, my findings are inconclusive. While searching for squirrel dreys, I did notice two other interesting things I would like to share.
First, there are fewer squirrel dreys on the Learning Campus than there are in my neighborhood. I suspect that is because the Garden is home to our friend the red-tailed hawk (from a previous blog post) and other predators that are more scarce around my home.
Second, I found a squirrel drey at the Garden that was built with something unusual. If you look carefully in the picture, you will see a green material, possibly shredded plastic like Easter basket grass, sticking out of the bottom. Now, I wonder where it found that! This drey is located on the Garden’s entrance road, near the entrance to the Barbara Carr Administrative Center, before you reach the Gatehouse. You will only notice it if you are looking at squirrel dreys as carefully as I am.
Take a look at the squirrel dreys around your home, nearby parks, and at the Garden. Are the the squirrels building over the road in your area? Have you seen a squirrel enter or leave a drey? What is the strangest material they have used to build it? If you notice any patterns, post a comment in this blog.
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