Bulborbs are nocturnal creatures, and sleep in open locations during the day. In the main series of games, this exposes them to being attacked by Pikmin, as they won't wake up until they are attacked. However, Dwarf Bulborbs and Dwarf Bulbears in Pikmin will let out a screech when agitated, awakening any nearby Bulborbs. An object being carried adjacent to a Bulborb can also wake up the enemy. Once awake, they become aggressive, and will run towards nearby Pikmin and lunge at them to try eat.