blue whale vs Common Tern

Balaenoptera musculus compared with Sterna hirundo

Key Differences

• blue whale is Vulnerable while Common Tern is Endangered.

Taxonomic Classification

Rank	blue whale	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	Balaenopteridae (Rorquals)	Laridae
Genus	Balaenoptera (Rorquals)	Sterna
Species	Balaenoptera musculus	Sterna hirundo

Evolutionary Relationship

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

Conservation Status

blue whale

VU — Vulnerable

Population: ~15.0K

Trend: Increasing ↑

Common Tern

EN — Endangered

Physical Characteristics

Attribute	blue whale	Common Tern
Diet	Carnivore	—
Average Lifespan	90 years	—
Average Length	30.0 m	—
Average Weight	150.0 t	—

Habitat & Geographic Range

blue whale

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, tropical and subtropical dry broadleaf forests, and tropical and subtropical grasslands and savannas, among 11 distinct biome types. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Asia (Taiwan), Europe (4 countries), and South America (Colombia, Ecuador). Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its 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.

blue whale

The largest animal ever known to have lived on Earth, blue whales can reach 33 meters and 200 tonnes — their hearts alone weigh as much as a small car. Found in all oceans, they migrate between polar feeding grounds and tropical breeding areas. Filter feeders consuming up to 4 tonnes of krill daily. Endangered, with global populations estimated at 10,000–25,000 after near-extinction from 20th-century whaling.

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 6 countries:

🇨🇴 Colombia 🇩🇰 Denmark 🇪🇨 Ecuador 🇳🇴 Norway 🇵🇹 Portugal 🇸🇪 Sweden