Common Seal vs Small Adder's-Tongue

Phoca vitulina compared with Ophioglossum azoricum

Key Differences

• Common Seal is Near Threatened while Small Adder's-Tongue is Critically Endangered.

Taxonomic Classification

Rank	Common Seal	Small Adder's-Tongue
Kingdom	Animalia (Animals)	Plantae (Plants)
Phylum	Chordata (Chordates)	Tracheophyta
Class	Mammalia (Mammals)	Polypodiopsida (Polypodiopsida)
Order	Pinnipedia (Seals & Sea Lions)	Ophioglossales (Ophioglossales)
Family	Phocidae (True Seals)	Ophioglossaceae
Genus	Phoca (Harbor Seals)	Ophioglossum
Species	Phoca vitulina	Ophioglossum azoricum

Conservation Status

Common Seal

NT — Near Threatened

Population: ~500.0K

Trend: Stable →

Small Adder's-Tongue

CR — Critically Endangered

Physical Characteristics

Attribute	Common Seal	Small Adder's-Tongue
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.

Small Adder's-Tongue

Habitat

Inhabits boreal forests and taiga within the Palearctic biogeographic realm. Populations are also found in montane and highland environments at higher elevations.

Range

Distributed across Belgium, Iceland, Norway, Portugal, and Sweden. Currently classified as Critically Endangered 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 4 countries:

🇧🇪 Belgium 🇳🇴 Norway 🇵🇹 Portugal 🇸🇪 Sweden