A resident intertidal species with homing behavior (Ref. 32612). Mainly found in saltwater marshes and in tidal creeks. May leave tide pools if aquatic conditions become inhospitable (Ref. 31184). Enters fresh water to limited extent (Ref. 7251). Not a seasonal killifish. Breathes air when out of water (Ref. 31184). Difficult to maintain in aquariums (Ref. 27139). Its introduction has caused the decline of native species and near extinction of Aphanius baeticus in southwestern Spain (Ref. 59043).