Its way worse of a problem than raiders because at least 20 boomrats running into my base even when my turrets cant even shoot them it onetime took out almost my entire base because metal walls can also somehow spread fire so i think you should be able to tell your turrets to shoot the animals that come into your base
Just hunt them to extinction. A preventive strike, that should do the trick.
Hunting them dont work they will just spawn if there is to small number of them on the map.
Currently either start applying advenced tactics ( controling every colonist and bashing space each second :D) or get yourself a mod with remade turrets that shots them.
EDIT: Ugh dont listen to me :D
Alpha 5 got turrets that shot insane animals