If you have not already done so, contain the orphaned baby as directed below. Then immediately contact a wildlife rehabilitator for assistance. If you cannot contain the animal, contact a wildlife rehabilitator to ask for further advice.
Do not touch baby squirrels more than necessary
IMPORTANT: As with all wild animals, direct handling of baby squirrels should be kept to a minimum. We are predators to wild animals and any contact with humans is stressful for them, though their stress may not always be obvious. Older babies, when stressed, may try to bite or scratch you if you handle them directly. It is additionally important to avoid handling babies in order to keep them wild and to avoid transferring bacteria, fungi, and parasites between humans and wild animals.
How to contain a baby squirrel
Step 1: Find the right container
Get a cardboard box (with air holes) big enough to comfortably contain the baby, or for squirrels who are very active, a wire cage. The box or cage should have a secure lid, or doors/flaps that close firmly. Line the container with a small towel.
Step 2: Catch the squirrel
If the squirrel is not very fast on its feet, approach the animal and drape a towel or pillowcase over the animal’s whole body, including its head. Wear thick garden gloves.
Step 3: Put the squirrel in your container
Scoop the animal up in the material, and place it inside the box. Remove the covering material carefully and quickly close the box. If the squirrel is too mobile to handle in this way, then place the cage or box upside down overtop of him/her, slide a flat piece of cardboard underneath, and secure the cardboard “floor” to the container with string or duct tape.
Step 4: Give the baby a heat source
Even on warm days, baby squirrels can quickly become hypothermic. The best thing to use is a heating pad set on LOW under half of the box, because it provides a nice consistent source of heat. If you don’t have a heating pad, you can use chemical hand warmers (commercially called “Hot Paws” or similar), microwaveable heat bags or a bottle filled with hot water placed inside the box.
Do not give the baby squirrel food or water
Do not give the baby anything to eat or drink. Instead, contact a rehabilitator. In many cases you will have to leave a message. If you do not receive a call back within several hours (or by the next morning if you call after 6PM), try contacting a different wildlife rehabilitator for advice.