brown bear vs Common Water Rat

Ursus arctos compared with Hydromys chrysogaster

Key Differences

• brown bear is Extinct while Common Water Rat is Least Concern.

Taxonomic Classification

Rank	brown bear	Common Water Rat
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Chordata (Chordates)	Chordata (Chordates)
Class same	Mammalia (Mammals)	Mammalia (Mammals)
Order	Carnivora (Carnivorans)	Rodentia (Rodents)
Family	Ursidae (Bears)	Muridae (Mice & Rats)
Genus	Ursus (Bears)	Hydromys
Species	Ursus arctos	Hydromys chrysogaster

Evolutionary Relationship

brown bear and Common Water Rat share a common ancestor at the Class level: Mammalia. (Mammals)

Conservation Status

brown bear

EX — Extinct

Population: ~200.0K

Trend: Stable →

Common Water Rat

LC — Least Concern

Physical Characteristics

Attribute	brown bear	Common Water Rat
Diet	Omnivore	—
Average Lifespan	25 years	—
Average Length	2.0 m	—
Average Weight	300.0 kg	—

Habitat & Geographic Range

brown bear

Habitat

Typically found in a wide range of habitat types.

Range

Found across Europe (6 countries).

Common Water Rat

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

brown bear

The world's most widely distributed bear species, brown bears range from North America and Europe across Russia to Japan, occupying forests, tundra, and alpine meadows. Adults can weigh up to 700 kg in coastal Alaskan populations. Omnivores that consume berries, roots, fish, and carrion, brown bears are a keystone species that distribute nutrients across landscapes. Most populations are stable, though some subspecies are threatened.

Common Water Rat

<em>Hydromys chrysogaster</em>, commonly known as the common water rat or rakali, is a semi-aquatic rodent in the family Muridae, native to Australia and New Guinea. It is classified as Least Concern by the IUCN, reflecting its relatively stable population across a broad range of freshwater and estuarine habitats on the Australian continent and associated islands. The species typically inhabits the banks of rivers, lakes, wetlands, and estuaries, where it constructs burrows in streambanks. It is highly adapted for an aquatic lifestyle, with partially webbed hind feet, a flattened head, and a dense waterproof coat. <em>Hydromys chrysogaster</em> is a carnivore, typically feeding on fish, crustaceans, mussels, frogs, and aquatic invertebrates, which it often carries to elevated feeding platforms to consume. The species is nocturnal and crepuscular, most active during early morning and evening hours near the water's edge. Biological traits including average lifespan, body length, and weight remain poorly documented in standardized databases, though adults are generally robust for a rodent, reportedly reaching body lengths of 20–35 cm excluding the tail. Geographic range details for this particular record remain incompletely documented in available data sources. Ecologically, the common water rat is an important apex predator in small-scale freshwater food webs and serves as an indicator species for wetland health in Australian riparian systems.