Woodpeckers will drill small foraging holes into the fascia looking for carpenter bees and other insects or drumming holes to attract a mate.
Tree squirrels and raccoons will chew through the eave to gain access to the attic or walls. Smaller holes usually indicate a squirrel has taken up residence, while larger holes provide access for larger animals like raccoons.
Newspaper can be stuffed into the hole to see if the animal is still using the site. If the paper is not removed after three days it is safe to start repairs. If the paper is removed, the animal(s) will need to be removed before repairs can begin.