When you own a pet rabbit, you'll occasionally hear it thump its back foot — a motion that results in a dull thud but one with a surprising amount of volume for such a small animal. Rabbits thump their feet when they detect danger, but there's a good chance that your house-dwelling rabbit is never actually in danger. A thump here and there isn't a big deal, but if you're aware of your rabbit thumping frequently, you'll want to be sure that the rabbit isn't in distress in some way.