I go with M.Red's answer "when there is no sound".
We are used to hear sounds all the time. So real silence is a hugh problem for us and it suggest trouble and other things.

The barking for the deers is meh and they dont do it like that in real all the time only at certain times. So this whole time barking is more annoying then anything else.
I have run into deer by enyoing m time in the woods many times and I have never heard them make sounds. Either they run away or they hide and when you get to far near them then they jump up and run away. Had this was a fawn half a year ago +- we both were surprised.