Common Seal vs Northern Dusky Slug

Phoca vitulina compared with Arion fuscus

Key Differences

• Common Seal is Near Threatened while Northern Dusky Slug is Data Deficient.

Taxonomic Classification

Rank	Common Seal	Northern Dusky Slug
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Chordata (Chordates)	Mollusca (Mollusks)
Class	Mammalia (Mammals)	Gastropoda (Gastropoda)
Order	Pinnipedia (Seals & Sea Lions)	Stylommatophora (Stylommatophora)
Family	Phocidae (True Seals)	Arionidae
Genus	Phoca (Harbor Seals)	Arion
Species	Phoca vitulina	Arion fuscus

Evolutionary Relationship

Common Seal and Northern Dusky Slug share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

Common Seal

NT — Near Threatened

Population: ~500.0K

Trend: Stable →

Northern Dusky Slug

DD — Data Deficient

Physical Characteristics

Attribute	Common Seal	Northern Dusky Slug
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.

Northern Dusky Slug

Habitat

Typically found in terrestrial and aquatic habitats including forests and freshwater.

Range

Found across Europe (7 countries).

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 🇩🇰 Denmark 🇳🇴 Norway 🇸🇪 Sweden