common hydra vs European otter

Hydra vulgaris compared with Lutra lutra

Key Differences

• common hydra is Not Evaluated while European otter is Vulnerable.

Taxonomic Classification

Rank	common hydra	European otter
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Cnidaria (Cnidarians)	Chordata (Chordates)
Class	Hydrozoa (Hydrozoa)	Mammalia (Mammals)
Order	Anthoathecata (Anthoathecata)	Carnivora (Carnivorans)
Family	Hydridae	Mustelidae (Weasels & Otters)
Genus	Hydra	Lutra (Otters)
Species	Hydra vulgaris	Lutra lutra

Evolutionary Relationship

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

Conservation Status

common hydra

NE — Not Evaluated

European otter

VU — Vulnerable

Trend: Stable →

Physical Characteristics

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

Habitat & Geographic Range

common hydra

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Denmark, Norway, and Sweden.

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.

common hydra

<em>Hydra vulgaris</em>, commonly known as the common hydra, is a small freshwater cnidarian in the family Hydridae. Its conservation status has not been formally evaluated by the IUCN. The species is recorded from Denmark, Norway, and Sweden, with its native range understood to encompass Europe broadly. It typically inhabits slow-moving or still freshwater bodies such as ponds, lakes, and streams, where it attaches to aquatic vegetation or submerged substrates. The common hydra is notable for its remarkable regenerative capabilities and has been the subject of substantial biological research. Diet information for this species is not available in current records. Biological traits of this species remain poorly documented in the scientific literature.

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