Blue Dolphin vs Common Eider

Stenella coeruleoalba compared with Somateria mollissima

Key Differences

• Blue Dolphin is Least Concern while Common Eider is Near Threatened.

Taxonomic Classification

Rank	Blue Dolphin	Common Eider
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Chordata (Chordates)	Chordata (Chordates)
Class	Mammalia (Mammals)	Aves (Birds)
Order	Cetacea (Whales & Dolphins)	Anseriformes (Anseriformes)
Family	Delphinidae (Oceanic Dolphins)	Anatidae
Genus	Stenella	Somateria
Species	Stenella coeruleoalba	Somateria mollissima

Evolutionary Relationship

Blue Dolphin and Common Eider share a common ancestor at the Phylum level: Chordata. (Chordates)

Conservation Status

Blue Dolphin

LC — Least Concern

Common Eider

NT — Near Threatened

Physical Characteristics

Attribute	Blue Dolphin	Common Eider
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Blue Dolphin

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Range

Widely distributed across Asia (Taiwan), Europe (5 countries), and South America (Colombia, Ecuador, Venezuela).

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.

Blue Dolphin

Blue Dolphin (Stenella coeruleoalba) is classified as Least Concern (LC) on the IUCN Red List. Widespread and abundant across its range, with stable populations and no immediate conservation concerns.

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.

Shared Countries

Both species can be found in 4 countries:

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