Little is known about the biology of the cave salamander as it lives in caves and is difficult to study. Most observations are therefore from captive specimens. It feeds on insect larvae, molluscs and amphipod crustaceans, detecting its prey in total darkness by using chemical cues in the water (3).
Most male cave salamanders establish a territory during the breeding season, and furiously protect them from other males (3). When a female enters the territory, courtship begins. The male deposits a spermatophore, which the female picks up with her cloaca. Courtship can be repeated several times within a few hours, and the fertilized eggs are held inside the female's body (3). These eggs, 12 to 70 in number, may be deposited beneath a stone, and guarded by the male and female until they hatch. Alternatively, just one or two eggs may develop inside the female, the rest breaking down to provide nutrients for the female and the remaining developing offspring. In this case the female eventually gives birth to well-developed larvae (2). There is no clear metamorphosis and the adult cave salamander maintains many juvenile characteristics throughout its life such as gills. Cave salamanders reach sexual maturity after seven years, and are estimated to live for up to 58 years (3).