Although axolotls lack eardrums, they have a complex inne ear sytem. Research indicate that they can hear lo frequency sounds and that the inner ear is sensitive to ground borne vibrations as well.
As an alternative way of hearing, they have a lateral line system b which the monitor water movement and detect predators and prey. Th lateral line is a series of pitlike depressions containing hair cells or mechanoreceptive neuromast, and is located along the head and sides of the animal. The lateral line system also contains ampullaru organs, electroreceptors that help in orientation to find prey and escape predators.