trinta-réis-das-rocas vs garajau-de-dorso-castanho

The Sooty Tern and Bridled Tern can be distinguished by their nesting habits and behavior at sea. Sooty Terns form large, dense colonies on open sandy substrates, while Bridled Terns prefer more dispersed colonies in sheltered crevices. At sea, Sooty Terns often feed in large flocks, unlike the more solitary Bridled Terns.

Look for Sooty Terns in large, noisy colonies on sandy islands, often feeding in flocks. Bridled Terns are more solitary, often found near marine flotsam and nesting in crevices.

Sooty Terns are known for their ability to stay airborne for years and rarely rest on water, while Bridled Terns are more likely to be seen near land and associate closely with marine flotsam.

Sooty Terns nest in large colonies on remote islands with sandy substrates, whereas Bridled Terns nest in more dispersed colonies in sheltered crevices.