Common Tern vs Pallas's squirrel, Red-bellied tree squirrel

Sterna hirundo compared with Callosciurus erythraeus

Key Differences

• Common Tern is Endangered while Pallas's squirrel, Red-bellied tree squirrel is Not Evaluated.

Taxonomic Classification

Rank	Common Tern	Pallas's squirrel, Red-bellied tree squirrel
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Chordata (Chordates)	Chordata (Chordates)
Class	Aves (Birds)	Mammalia (Mammals)
Order	Charadriiformes (Charadriiformes)	Rodentia (Rodents)
Family	Laridae	Sciuridae (Squirrels)
Genus	Sterna	Callosciurus
Species	Sterna hirundo	Callosciurus erythraeus

Evolutionary Relationship

Common Tern and Pallas's squirrel, Red-bellied tree squirrel share a common ancestor at the Phylum level: Chordata. (Chordates)

Conservation Status

Common Tern

EN — Endangered

Pallas's squirrel, Red-bellied tree squirrel

NE — Not Evaluated

Physical Characteristics

Attribute	Common Tern	Pallas's squirrel, Red-bellied tree squirrel
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Common Tern

Habitat

Found across multiple habitat types including tropical and subtropical dry broadleaf forests, flooded grasslands and savannas, and montane grasslands and shrublands, among 9 distinct biome types spanning the Neotropic and Palearctic realms. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Europe (7 countries), North America (United States), and South America (Colombia, Ecuador, Venezuela). Currently classified as Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

Pallas's squirrel, Red-bellied tree squirrel

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Range

Widely distributed across Asia (China, Japan), Europe (8 countries), and South America (Argentina).

Common Tern

Common Tern (Sterna hirundo) is classified as Endangered (EN) on the IUCN Red List. At high risk of extinction in the wild, with significant population decline and ongoing threats to survival.

Shared Countries

Both species can be found in 4 countries:

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