Large-billed Tern vs Royal Tern

In short

The Large-billed Tern and Royal Tern can be distinguished primarily by their bills and wing patterns. The Large-billed Tern has a notably large, heavy bill and a striking wing pattern with black primaries and white secondaries. The Royal Tern, while also large, has a more slender bill and lacks the distinctive wing pattern.

Identification tips

1. Look for the large, heavy bill of the Large-billed Tern compared to the more slender bill of the Royal Tern. 2. Check for the distinctive wing pattern of black primaries and white secondaries in the Large-billed Tern. 3. Observe behavior: Royal Terns are often in noisy colonies, while Large-billed Terns may be in mixed-species groups. 4. Consider habitat: Large-billed Terns are more likely inland during breeding, while Royal Terns stick to coastal areas.

Size

Both species are large terns, but the Royal Tern is generally more slender with a longer body and wingspan compared to the more robust Large-billed Tern.

Plumage

The Large-billed Tern has a gray back with a distinctive wing pattern of black primaries and white secondaries. The Royal Tern has a mostly white body with a black cap during the breeding season and lacks the contrasting wing pattern.

Behaviour

Royal Terns are highly social and often found in noisy colonies, while Large-billed Terns are also social but can be seen nesting in mixed-species colonies with other terns and skimmers.

Habitat

Large-billed Terns are found along broad, inland rivers and lakes during breeding and coastal areas during nonbreeding. Royal Terns prefer isolated coastal sites, often on dredge-spoil islands, and migrate to warmer coastal regions in winter.

Voice

Royal Terns are typically noisy and conspicuous, while the vocalizations of the Large-billed Tern are less documented.