CHICAGO (CBS) — If you haven’t noticed as many squirrels in your yard as usual, you’re not alone.

As WBBM Newsradio’s Nick Young reports, there are indeed fewer squirrels around this year, and Steve Sullivan of the Peggy Notebaert Nature Museum says there are several reasons why.

Sullivan, who is part of a nationwide project based in Chicago called Project Squirrel, tells Chicago Wildlife News that the mild winter weather allowed most of the animals who would have died from cold or starvation to survive.

And that, Sullivan tells the publication, has meant more competition for young squirrels from older, stronger animals.

In addition, the triple-digit heat has caused some squirrels to die from exposure, or simply remain out of sight by staying in the shade, Sullivan told Chicago Wildlife News.

Project Squirrel calls on neighbors to step in as “citizen scientists” and record their observations on the Web site

LISTEN: WBBM Newsradio’s Nick Young reports

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