This small tern uses wetlands. In breeding plumage, its black head and dark grey underside stand out. It makes a nest from vegetation, floating or anchored, and both sexes care for the young.
In breeding plumage, the head is black, the cheeks and sides of the neck are white, and the underside is dark grey. The tail is shallowly forked, and the sexes are similar. In non-breeding plumage, the underside is white and the black on the head is streaked with white.
Whiskered Terns anchor nests to plants near the water surface. Researchers monitored five wetlands in Valencia, eastern Spain, from 2002 to 2009. Across 18 areas they recorded 663 nests, 1,618 eggs, and 777 nestlings. Over eight years they made 94 visits to 14 colonies.
Forty-nine percent of eggs hatched, 21.8% produced fledglings, and 29.1% of nestlings fledged. Nests were anchored at an average water depth of 44.1 centimetres, commonly between 25 and 80 centimetres; mean nest survival was 61.7%. After water-level fluctuations, an average of 25.6% of nests, 32.1% of eggs, and 31.9% of chicks were lost, although rain and predation also contributed. Breeding results varied among wetlands and years.
An extinction-risk assessment has not been added yet.
After nesting begins, sudden water-level changes can leave plant-anchored nests above or below the water and cause losses. In managed wetlands, the authors recommended keeping changes within 6 centimetres over one to two days once nests are established.