Common Seal vs Large-Neck Clam

Phoca vitulina compared with Mya arenaria

Key Differences

• Common Seal is Near Threatened while Large-Neck Clam is Vulnerable.

Taxonomic Classification

Rank	Common Seal	Large-Neck Clam
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Chordata (Chordates)	Mollusca (Mollusks)
Class	Mammalia (Mammals)	Bivalvia (Bivalvia)
Order	Pinnipedia (Seals & Sea Lions)	Myida (Myida)
Family	Phocidae (True Seals)	Myidae
Genus	Phoca (Harbor Seals)	Mya
Species	Phoca vitulina	Mya arenaria

Evolutionary Relationship

Common Seal and Large-Neck Clam share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

Common Seal

NT — Near Threatened

Population: ~500.0K

Trend: Stable →

Large-Neck Clam

VU — Vulnerable

Physical Characteristics

Attribute	Common Seal	Large-Neck Clam
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.

Large-Neck Clam

Habitat

Found across multiple habitat types including temperate broadleaf and mixed forests, temperate coniferous forests, and temperate grasslands and steppes, among 5 distinct biome types within the Palearctic biogeographic realm. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Asia (Georgia, Turkey), Europe (22 countries), and North America (Canada, United States). 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.

Large-Neck Clam

Large-Neck Clam (Mya arenaria) is classified as Vulnerable (VU) on the IUCN Red List. Facing a high risk of endangerment in the wild, with declining populations and increasing habitat pressure.

Shared Countries

Both species can be found in 8 countries:

🇧🇪 Belgium 🇩🇰 Denmark 🇳🇴 Norway 🇵🇹 Portugal 🇷🇺 Russia 🇸🇪 Sweden 🇺🇦 Ukraine 🇺🇸 United States