Irrawaddy dolphins prefer coastal areas, particularly muddy, brackish waters at river mouths and deltas, and do not appear to venture far offshore. Most sightings have been made within 1.6 km of the coastline, but some have been reported in waters greater than 5 km from shore. Some populations are apparently restricted to fresh water, e.g. Chilka Lake, India, and Songhkla, Thailand.
Range depth: 2.5 to 18.0 m.
Habitat Regions: tropical ; saltwater or marine ; freshwater
Aquatic Biomes: rivers and streams; coastal ; brackish water
Other Habitat Features: riparian ; estuarine