Commerson's dolphins inhabit shallow, inshore waters along coastlines, harbors, bays, and river mouths. The live in cold shallow waters, with temperatures ranging from 1˚ C to 16˚ C. They are rarely found at depths greater than 200 m. Commerson's dolphins prefer a neritic environment and are seldom found far offshore. Most sightings occur in the coastal regions near the mouths of bays and estuaries or over the wide shallow continental shelf where the tidal range is great. Commerson's dolphins move towards the shore with the tide. In some areas, dolphins prefer areas with the strongest currents - up to or greater than 15 km/hr. They are also frequently found in kelp beds and in narrow passages like those found in the Strait of Magellan. It is thought that most dolphins seasonally move away from the shore, following fish which move offshore during the winter. Commerson's dolphins in Kerguelen follow this trend and are less common inshore between June and December. In Kerguelen, they are most commonly observed over the Kerguelen shelf, but they are also found in open waters, kelp-ringed coastlines, and protected areas between islets.
Range depth: 200 (high) m.
Habitat Regions: temperate ; saltwater or marine ; freshwater
Aquatic Biomes: pelagic ; benthic ; rivers and streams; coastal