Brown Rat vs least weasel

Rattus norvegicus compared with Mustela nivalis

Key Differences

• Brown Rat is Least Concern while least weasel is Near Threatened.

Taxonomic Classification

Rank	Brown Rat	least weasel
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Chordata (Chordates)	Chordata (Chordates)
Class same	Mammalia (Mammals)	Mammalia (Mammals)
Order	Rodentia (Rodents)	Carnivora (Carnivorans)
Family	Muridae (Mice & Rats)	Mustelidae (Weasels & Otters)
Genus	Rattus	Mustela
Species	Rattus norvegicus	Mustela nivalis

Evolutionary Relationship

Brown Rat and least weasel share a common ancestor at the Class level: Mammalia. (Mammals)

Conservation Status

Brown Rat

LC — Least Concern

least weasel

NT — Near Threatened

Physical Characteristics

Attribute	Brown Rat	least weasel
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Brown Rat

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, tropical and subtropical dry broadleaf forests, and tropical and subtropical grasslands and savannas, among 10 distinct biome types. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Africa (11 countries), Asia (15 countries), Europe (41 countries), North America (16 countries), Oceania and the Pacific (10 countries), and South America (10 countries).

least weasel

Habitat

Found across multiple habitat types including temperate broadleaf and mixed forests, tundra, and tropical and subtropical moist broadleaf forests, among 4 distinct biome types spanning the Australasia and Oceanian and Palearctic realms.

Range

Widely distributed across Africa (Sao Tome and Principe), Asia (Cyprus), Europe (11 countries), and Oceania and the Pacific (New Zealand). Listed as Near Threatened, this species requires ongoing monitoring to prevent population decline.

Brown Rat

Brown Rat (Rattus norvegicus) 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.

least weasel

least weasel (Mustela nivalis) is classified as Near Threatened (NT) on the IUCN Red List. Close to qualifying as threatened, with populations that may become vulnerable without conservation action.

Shared Countries

Both species can be found in 14 countries:

🇧🇪 Belgium 🇨🇾 Cyprus 🇩🇰 Denmark 🇫🇷 France 🇬🇷 Greece 🇮🇹 Italy 🇲🇹 Malta 🇳🇿 New Zealand 🇳🇴 Norway 🇵🇹 Portugal 🇷🇺 Russia 🇸🇹 Sao Tome and Principe 🇪🇸 Spain 🇸🇪 Sweden