European otter vs Window Gnat

Lutra lutra compared with Sylvicola fenestralis

Key Differences

• European otter is Vulnerable while Window Gnat is Least Concern.

Taxonomic Classification

Rank	European otter	Window Gnat
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Chordata (Chordates)	Arthropoda (Arthropods)
Class	Mammalia (Mammals)	Insecta (Insects)
Order	Carnivora (Carnivorans)	Diptera (Diptera)
Family	Mustelidae (Weasels & Otters)	Anisopodidae
Genus	Lutra (Otters)	Sylvicola
Species	Lutra lutra	Sylvicola fenestralis

Evolutionary Relationship

European otter and Window Gnat share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

European otter

VU — Vulnerable

Trend: Stable →

Window Gnat

LC — Least Concern

Physical Characteristics

Attribute	European otter	Window Gnat
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.

Window Gnat

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

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

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.

Shared Countries

Both species can be found in 3 countries:

🇩🇰 Denmark 🇳🇴 Norway 🇸🇪 Sweden