I would hate to make a blanket statement about all animals. That being said, I really don't think it makes any difference to most animals. I have had them stand and stare at my IR cameras just as much as my white-flash camera. I have also gotten pics of the same animals over and over on both types of cameras so I guess if it bothered them they wouldn't keep coming back but they do.
Blessings.....Pastorjim