Mountain lions, also known as cougars, are actually able to whistle. While they are commonly quiet in the woods, sneaking up on prey through the bushes, mountain lions can choose to whistle, which sounds a lot like either a bird chirping or a human being whistling. So if you find yourself in the middle of the woods by yourself and you hear someone whistling, it might be better to mind your own business.
Please check your email and click on the link to confirm your email.
If you don't see an email in your inbox, make sure to check your spam/junk folder and move the email to your inbox so you don't miss future emails.