Commerson s Dolphin vs Common Loon

Cephalorhynchus commersonii compared with Gavia immer

Key Differences

• Commerson s Dolphin is Least Concern while Common Loon is Not Evaluated.

Taxonomic Classification

Rank	Commerson s Dolphin	Common Loon
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Chordata (Chordates)	Chordata (Chordates)
Class	Mammalia (Mammals)	Aves (Birds)
Order	Cetacea (Whales & Dolphins)	Gaviiformes (Gaviiformes)
Family	Delphinidae (Oceanic Dolphins)	Gaviidae
Genus	Cephalorhynchus	Gavia
Species	Cephalorhynchus commersonii	Gavia immer

Evolutionary Relationship

Commerson s Dolphin and Common Loon share a common ancestor at the Phylum level: Chordata. (Chordates)

Conservation Status

Commerson s Dolphin

LC — Least Concern

Common Loon

NE — Not Evaluated

Physical Characteristics

Attribute	Commerson s Dolphin	Common Loon
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Commerson s Dolphin

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Common Loon

Habitat

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

Range

Distributed across Belgium, Denmark, Norway, Sweden, and United States.

Commerson s Dolphin

<em>Cephalorhynchus commersonii</em>, commonly known as Commerson's Dolphin, is a small cetacean in the family Delphinidae. This species is classified as Least Concern on the IUCN Red List and is notable for its striking black-and-white coloration, which makes it one of the most visually distinctive dolphin species. Commerson's Dolphins typically inhabit coastal and nearshore marine environments of the Southern Hemisphere, particularly around the Falkland Islands, the southern tip of South America, and a geographically isolated population near the Kerguelen Islands in the Indian Ocean. These dolphins are highly social animals, often observed in small groups engaging in acrobatic behaviors near the surface. They typically feed on fish, squid, and crustaceans, often hunting cooperatively in shallow waters and kelp beds. Their average lifespan is approximately 18 years, and they are known for their fast, energetic swimming. Commerson's Dolphins are sometimes caught as bycatch in fishing nets, posing a localized conservation concern despite their overall Least Concern status.

Common Loon

<em>Gavia immer</em>, the common loon or great northern diver, is a large aquatic bird in the family Gaviidae, known for its haunting, yodeling calls across northern lakes. It is found in Belgium, Denmark, Norway, Sweden, and the United States, breeding on freshwater lakes in boreal and subarctic regions and wintering along marine coastlines. The common loon is adept in aerial, terrestrial, and aquatic environments, though it is most highly specialized for diving, using its strong feet positioned far back on its body to pursue fish underwater. It typically feeds on fish, supplemented by crustaceans and aquatic invertebrates. Its striking summer plumage features a black-and-white checkered back and a deep black head with a characteristic white necklace pattern. The species has not been evaluated for IUCN conservation status. Common loons require clear, fish-rich lakes for successful breeding and are sensitive to water quality degradation and human disturbance at nesting sites. Their distinctive calls are emblematic of wilderness in North America and Scandinavia.