Common Loon vs Great Reed Warbler

Gavia immer compared with Acrocephalus arundinaceus

Key Differences

• Common Loon is Not Evaluated while Great Reed Warbler is Critically Endangered.

Taxonomic Classification

Rank	Common Loon	Great Reed Warbler
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Chordata (Chordates)	Chordata (Chordates)
Class same	Aves (Birds)	Aves (Birds)
Order	Gaviiformes (Gaviiformes)	Passeriformes (Songbirds)
Family	Gaviidae	Acrocephalidae
Genus	Gavia	Acrocephalus
Species	Gavia immer	Acrocephalus arundinaceus

Evolutionary Relationship

Common Loon and Great Reed Warbler share a common ancestor at the Class level: Aves. (Birds)

Conservation Status

Common Loon

NE — Not Evaluated

Great Reed Warbler

CR — Critically Endangered

Physical Characteristics

Attribute	Common Loon	Great Reed Warbler
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Common Loon

Habitat

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

Range

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

Great Reed Warbler

Habitat

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

Range

Distributed across Belgium, Denmark, Luxembourg, Norway, and Sweden. Currently classified as Critically Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

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.

Great Reed Warbler

Great Reed Warbler (Acrocephalus arundinaceus) is classified as Critically Endangered (CR) on the IUCN Red List. Facing an extremely high risk of extinction in the wild due to severe population decline and habitat loss.

Shared Countries

Both species can be found in 4 countries:

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