Indian River Tern

The Indian river tern or just river tern  is a tern in the family Laridae. It is a resident breeder along inland rivers from Iran east into the Indian Subcontinent and further to Myanmar to Thailand, where it is uncommon. This is a medium-sized tern, 38–43 cm long with dark grey upperparts, white underparts, a forked tail with long flexible streamers, and long pointed wings. The bill is yellow and the legs red. It has a black cap in breeding plumage. In the winter the cap is greyish white, flecked and streaked with black, there is a dark mask through the eye, and the tip of the bill becomes dusky.
This species breeds from March to May in colonies in less accessible areas such as sandbanks in rivers. It nests in a ground scrape, often on bare rock or sand, and lays three greenish-grey to buff eggs, which are blotched and streaked with brown.
The river tern feeds by plunge-diving for fish, crustaceans, tadpoles and aquatic insects in rivers, lakes, and tanks. Its numbers are decreasing due to the pollution of their habitat.