placental bag.] The newborn is well-developed with eyes open. Within two weeks the baby will begin eating vegetation. In. the wild, porcupines live as long as 10 years while captive porcupines have lived as long as 20 years. Due to their protective quills, porcupines have few predators. Porcupines do not throw their quills, although the quills of a. frightened porcupine are more easily detached.