Common Seal vs

Phoca vitulina compared with Nitzschia flexa

Key Differences

Common Seal is Near Threatened while is Not Evaluated.

Taxonomic Classification

Rank	Common Seal
Kingdom	Animalia (Animals)	Chromista (Chromista)
Phylum	Chordata (Chordates)	Ochrophyta (Ochrophyta)
Class	Mammalia (Mammals)	Bacillariophyceae (Bacillariophyceae)
Order	Pinnipedia (Seals & Sea Lions)	Bacillariales (Bacillariales)
Family	Phocidae (True Seals)	Bacillariaceae
Genus	Phoca (Harbor Seals)	Nitzschia
Species	Phoca vitulina	Nitzschia flexa

Conservation Status

Common Seal

NT — Near Threatened

Population: ~500.0K

Trend: Stable →

NE — Not Evaluated

Physical Characteristics

Attribute	Common Seal
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.

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Norway and Sweden.

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.

Nitzschia flexa is a pennate diatom (class Bacillariophyceae) with a characteristically curved or bent raphe system that gives the genus its distinctive appearance. It inhabits freshwater to brackish environments and contributes to benthic and planktonic algal communities. As a photosynthetic microalga, it plays a foundational role in aquatic food webs and primary production.