European otter vs Ruff

Lutra lutra compared with Calidris pugnax

Key Differences

• European otter is Vulnerable while Ruff is Least Concern.

Taxonomic Classification

Rank	European otter	Ruff
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Chordata (Chordates)	Chordata (Chordates)
Class	Mammalia (Mammals)	Aves (Birds)
Order	Carnivora (Carnivorans)	Charadriiformes (Charadriiformes)
Family	Mustelidae (Weasels & Otters)	Scolopacidae
Genus	Lutra (Otters)	Calidris
Species	Lutra lutra	Calidris pugnax

Evolutionary Relationship

European otter and Ruff share a common ancestor at the Phylum level: Chordata. (Chordates)

Conservation Status

European otter

VU — Vulnerable

Trend: Stable →

Ruff

LC — Least Concern

Physical Characteristics

Attribute	European otter	Ruff
Diet	Carnivore	—
Average Lifespan	10 years	—
Average Length	1.0 m	—
Average Weight	10.0 kg	—

Habitat & Geographic Range

European otter

Habitat

Typically found in diverse ecosystems where prey species are available.

Range

Found across Europe (6 countries). Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

Ruff

Habitat

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

Range

Widely distributed across Asia (Taiwan), Europe (4 countries), North America (United States), and South America (Colombia, Venezuela).

European otter

Sleek semi-aquatic mustelid found along clean rivers, streams, and coastlines across Europe and Asia. European otters can reach 1.3 meters in length and are highly skilled fish hunters, using sensitive whiskers to detect prey movements. Requiring unpolluted water with abundant fish, they are an indicator species for freshwater ecosystem health. Once nearly extinct in Western Europe from hunting and pollution, populations have recovered significantly following water quality improvements.

Ruff

Ruff (Calidris pugnax) 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.

Shared Countries

Both species can be found in 4 countries:

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