Common Seal vs River Tern

Phoca vitulina compared with Sterna aurantia

Key Differences

• Common Seal is Near Threatened while River Tern is Vulnerable.

Taxonomic Classification

Rank	Common Seal	River Tern
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Chordata (Chordates)	Chordata (Chordates)
Class	Mammalia (Mammals)	Aves (Birds)
Order	Pinnipedia (Seals & Sea Lions)	Charadriiformes (Charadriiformes)
Family	Phocidae (True Seals)	Laridae
Genus	Phoca (Harbor Seals)	Sterna
Species	Phoca vitulina	Sterna aurantia

Evolutionary Relationship

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

Conservation Status

Common Seal

NT — Near Threatened

Population: ~500.0K

Trend: Stable →

River Tern

VU — Vulnerable

Physical Characteristics

Attribute	Common Seal	River Tern
Diet	Carnivore	—
Average Lifespan	30 years	—
Average Length	1.7 m	—
Average Weight	80.0 kg	—

Habitat & Geographic Range

Common Seal

Habitat

Typically found in diverse ecosystems where prey species are available.

Range

Found across Europe (7 countries) and North America (United States). Listed as Near Threatened, this species requires ongoing monitoring to prevent population decline.

River Tern

Habitat

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

Range

Found in Norway. Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

Common Seal

The most widely distributed pinniped, harbor seals inhabit temperate and subarctic coastal waters of both the North Atlantic and North Pacific. Adults reach up to 130 kg and spend roughly equal time at sea hunting fish, squid, and crustaceans and hauling out on beaches or rocks to rest. Their large, expressive eyes are adapted for underwater vision in low light. Harbor seals are a critical food source for orcas, sharks, and polar bears.

Shared Countries

Both species can be found in 1 countries:

🇳🇴 Norway