Common Eider vs common grey sea slug

Somateria mollissima compared with Aeolidia papillosa

Key Differences

• Common Eider is Near Threatened while common grey sea slug is Least Concern.

Taxonomic Classification

Rank	Common Eider	common grey sea slug
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Chordata (Chordates)	Mollusca (Mollusks)
Class	Aves (Birds)	Gastropoda (Gastropoda)
Order	Anseriformes (Anseriformes)	Nudibranchia (Nudibranchia)
Family	Anatidae	Aeolidiidae
Genus	Somateria	Aeolidia
Species	Somateria mollissima	Aeolidia papillosa

Evolutionary Relationship

Common Eider and common grey sea slug share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

Common Eider

NT — Near Threatened

common grey sea slug

LC — Least Concern

Physical Characteristics

Attribute	Common Eider	common grey sea slug
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Common Eider

Habitat

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

Range

Found across Europe (5 countries) and North America (United States). Listed as Near Threatened, this species requires ongoing monitoring to prevent population decline.

common grey sea slug

Habitat

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

Range

Distributed across Belgium, Chile, Denmark, Norway, and Sweden.

Common Eider

Common Eider (Somateria mollissima) is classified as Near Threatened (NT) on the IUCN Red List. Close to qualifying as threatened, with populations that may become vulnerable without conservation action.

common grey sea slug

<em>Aeolidia papillosa</em>, commonly known as the common grey sea slug, is a nudibranch mollusc belonging to the genus Aeolidia within the family Aeolidiidae. Despite the species name referencing terrestrial and aquatic habitats including forests and freshwater, <em>Aeolidia papillosa</em> is primarily a marine organism. Its range includes Belgium, Chile, Denmark, Norway, and Sweden, indicating a distribution across the North Atlantic and into South American waters. Common grey sea slug is assessed as Least Concern on the IUCN Red List. The species is typically found in intertidal and subtidal zones, where it preys on sea anemones and stores stinging cells from its prey in its dorsal cerata for defense. Biological traits of this species remain poorly documented in the scientific literature.

Shared Countries

Both species can be found in 4 countries:

🇧🇪 Belgium 🇩🇰 Denmark 🇳🇴 Norway 🇸🇪 Sweden