Blue Dolphin vs Common Tern

Stenella coeruleoalba compared with Sterna hirundo

Key Differences

• Blue Dolphin is Least Concern while Common Tern is Endangered.

Taxonomic Classification

Rank	Blue Dolphin	Common Tern
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Chordata (Chordates)	Chordata (Chordates)
Class	Mammalia (Mammals)	Aves (Birds)
Order	Cetacea (Whales & Dolphins)	Charadriiformes (Charadriiformes)
Family	Delphinidae (Oceanic Dolphins)	Laridae
Genus	Stenella	Sterna
Species	Stenella coeruleoalba	Sterna hirundo

Evolutionary Relationship

Blue Dolphin and Common Tern share a common ancestor at the Phylum level: Chordata. (Chordates)

Conservation Status

Blue Dolphin

LC — Least Concern

Common Tern

EN — Endangered

Physical Characteristics

Attribute	Blue Dolphin	Common Tern
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Blue Dolphin

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Range

Widely distributed across Asia (Taiwan), Europe (5 countries), and South America (Colombia, Ecuador, Venezuela).

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.

Blue Dolphin

Blue Dolphin (Stenella coeruleoalba) 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.

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.

Shared Countries

Both species can be found in 8 countries:

🇧🇪 Belgium 🇨🇴 Colombia 🇩🇰 Denmark 🇪🇨 Ecuador 🇳🇴 Norway 🇵🇹 Portugal 🇸🇪 Sweden 🇻🇪 Venezuela