Rule 16.1
Animal hole
Also searched as: rabbit hole, mole hill, burrow, animal scrape
Until 2019: hole made by a burrowing animal
A hole dug in the ground by an animal, including the loose material dug out and any track leading into it. It is an abnormal course condition, so you get free relief.
Mole hills and ground pushed up by an animal digging underground also count. You get relief if the animal hole interferes with your lie, stance or swing, and on the putting green also with your line of play.
If your ball lies in a penalty area, there is no free relief from an animal hole. You play the ball as it lies or take penalty area relief for one penalty stroke.
Until 2018 the rule only covered holes made by burrowing animals. Since 2019 any animal counts, except worms and insects.