Extremely rare, known to breed on a few small, remote islands off the coast of eastern China (e.g., Mazu Islands). Wintering grounds are poorly known but believed to be in Southeast Asia.

Look for its large size, shaggy black crest, yellow bill with a black tip, and grey upperparts contrasting with white underparts. Due to its extreme rarity and critically endangered status, observations are usually limited to specific, protected areas, often requiring specialized permits and expert guidance. Identification is often confirmed by association with Greater Crested Terns.

Observation is extremely challenging due to its rarity and sensitivity. Breeding occurs from May to August. Any observation is a significant event. Only experienced researchers and conservationists should attempt to find them in breeding areas to avoid disturbance.