Common Tern vs Red-billed Duck

Sterna hirundo compared with Anas erythrorhyncha

Key Differences

• Common Tern is Endangered while Red-billed Duck is Least Concern.

Taxonomic Classification

Rank	Common Tern	Red-billed Duck
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Chordata (Chordates)	Chordata (Chordates)
Class same	Aves (Birds)	Aves (Birds)
Order	Charadriiformes (Charadriiformes)	Anseriformes (Anseriformes)
Family	Laridae	Anatidae
Genus	Sterna	Anas
Species	Sterna hirundo	Anas erythrorhyncha

Evolutionary Relationship

Common Tern and Red-billed Duck share a common ancestor at the Class level: Aves. (Birds)

Conservation Status

Common Tern

EN — Endangered

Red-billed Duck

LC — Least Concern

Physical Characteristics

Attribute	Common Tern	Red-billed Duck
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Common Tern

Habitat

Found across multiple habitat types including tropical and subtropical dry broadleaf forests, flooded grasslands and savannas, and montane grasslands and shrublands, among 9 distinct biome types spanning the Neotropic and Palearctic realms. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Europe (7 countries), North America (United States), and South America (Colombia, Ecuador, Venezuela). Currently classified as Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

Red-billed Duck

Habitat

Typically found in various aerial, terrestrial, and aquatic environments.

Range

Found across Europe (6 countries) and South America (Ecuador).

Common Tern

Common Tern (Sterna hirundo) is classified as Endangered (EN) on the IUCN Red List. At high risk of extinction in the wild, with significant population decline and ongoing threats to survival.

Red-billed Duck

Red-billed Duck (Anas erythrorhyncha) is classified as Least Concern (LC) on the IUCN Red List. Widespread and abundant across its range, with stable populations and no immediate conservation concerns.

Shared Countries

Both species can be found in 3 countries:

🇧🇪 Belgium 🇪🇨 Ecuador 🇳🇴 Norway