We have deer that pass through our yard every evening and morning. Do deer eat or otherwise destroy plastic signs? We've had to replace our ADT sign in the front yard numerous times. They don't seem to bother the one we have behind the house, if indeed, that's what's destroying our sign.
Orange County North Carolina
I'm sorry but deer can't read....They don't realize your house is protected....
Yes deer will browse on anything new or interesting. ADT may make their signs out of something that is earth friendly or something deer crave such as a mineral, and otherwise drawn to the sign.
I would suggest to you that two legged friend may be your thief. It may be desirable for kids to prank a neighbor and take away their sign. Is the whole sign gone or just the plastic? Does it look like the post is being pulled straight up or is it more of a drag mark?
A Ring or nest doorbell or a trail camera will positively identify the culprit. If you already have one, put the sign within the range of the camera.