These situations are always a bit tricky as there are many variables to consider. If at anytime you are not sure what to do, call your local wildlife rehabilitation centre. They will be happy to talk with you to determine how to best handle your specific situation. However, the information below will hopefully provide you with some guidance.
First, while the rabbit may look too small to be on its own, it might be just fine. In fact, if the rabbit is at least 10 cm long and has its eyes open, the rabbit is already independent from its mother and if not injured, it should be fine. While it may not be full grown, Cottontail Rabbits are weaned and on their own at about three to four weeks of age.
If you attempt to catch the rabbit and it runs away, trying to escape its capture, chances are it’s ok and should be left alone.
If the rabbit is smaller than your fist and doesn’t try to run away when you approach, it is too young to be on its own. If you know where the nest is, you can place it back in the nest. Once placed in the nest you can do the string test to ensure the mother is coming back. Just place some string in the shape of an ‘x’ over the nest. If the ‘x’ is disturbed, it’s an indication that the mother was back to feed. The mother doesn’t stay at the nest for long. She typically comes a few times a day to feed and that’s it!
If you are concerned that the young rabbit has been abandoned or orphaned, if there are visible signs of an injury, if it’s easy to catch, if it’s laying on its side and can’t get up, these are signs that the rabbit needs help.
It is important to be as quiet as possible. Rabbits stress very easily. Gently place the rabbit in a cardboard box with a soft towel and place in a dark, quiet room until details get sorted. While you may want to feed the rabbit and give it some water, it is very important not to do this. Keep pets and children away and call your local wildlife rehabilitation centre to assess the situation.