3 to 5 day old bunnies.
Baby bunnies have the best chance of living if they can be left at the nest site.
If possible, protect them from predators such as cats and dogs by placing a laundry basket (with holes in the sides) upside down over the nest during the day. Weight it down with something heavy like a brick or a jug of water. This will make a temporary cage to keep them from harm. Take the basket off at night so the mother can come and let the babies nurse.
If you know for sure that the mother has been killed, or if the babies have injuries, then call us and set up a time to bring them to us.

Also see our "Emergency Information" page