Ganges river dolphins are usually solitary creatures (9). The eye lacks a lens and therefore functions solely as a means of detecting the direction of light. In the muddy waters of their habitat, good eyesight is not needed, and echolocation is used to detect food and navigate (5). Individuals tend to swim with one flipper trailing along the substrate (4), and will root around with their beak to disturb and detect the shrimp and fish upon which they feed (5).   Births may take place year round but appear to be concentrated between December to January, and March to May (9). After around one year, juveniles are weaned and they reach sexual maturity at about ten years of age (5). During the monsoon, dolphins tend to migrate to tributaries of the main river systems (9). Occasionally, individuals swim along with their beak emerging from the water (7), and they may 'breach', jumping partly or completely clear of the water and landing on the side of the body (7).