The male baby, also called a porcupette, hasn't been named yet but can be viewed by the public.
Zoo officials say the baby is healthy and doing fine. It will stay on the ground for a few weeks until it learns to eat vegetation and climb the nearby trees.
Until then, Athena will come down from the trees at night to be with the baby.
The zoo says the exhibit is next to the penguin display.
For more information visit the Zoo Boise website.