Behaviour Most of this species is migratory² although individuals breeding in East African may remain in their breeding range throughout the year¹. It breeds with other tern species in well-dispersed colonies of 10-200 pairs (sometimes up to 900 pairs)¹, and remains gregarious throughout the year². Habitat The species inhabits tropical coasts and inshore waters, foraging mainly within 3 km of land over coral reefs or occasionally up to 10 km offshore¹. It nests on rock, sand, gravel or coral islands¹, bare and exposed sandflats and sparsely vegetated open ground on sand-dunes and above the high-water mark on beaches². Diet Its diet consists of small fish (average 5 cm long) and invertebrates¹. Breeding site The nest is a shallow scrape on rock, sand, gravel or coral in barren or sparsely vegetated areas on islands¹, sandflats, sand-dunes and beaches².