Canadian beaver vs Ray's Knotgrass

Castor canadensis compared with Polygonum oxyspermum

Key Differences

• Canadian beaver is Not Evaluated while Ray's Knotgrass is Endangered.

Taxonomic Classification

Rank	Canadian beaver	Ray's Knotgrass
Kingdom	Animalia (Animals)	Plantae (Plants)
Phylum	Chordata (Chordates)	Magnoliophyta (Flowering Plants)
Class	Mammalia (Mammals)	Magnoliopsida (Dicots)
Order	Rodentia (Rodents)	Caryophyllales (Caryophyllales)
Family	Castoridae (Beavers)	Polygonaceae
Genus	Castor (Beavers)	Polygonum
Species	Castor canadensis	Polygonum oxyspermum

Conservation Status

Canadian beaver

NE — Not Evaluated

Population: ~15.0M

Trend: Stable →

Ray's Knotgrass

EN — Endangered

Physical Characteristics

Attribute	Canadian beaver	Ray's Knotgrass
Diet	Herbivore	—
Average Lifespan	15 years	—
Average Length	1.0 m	—
Average Weight	25.0 kg	—

Habitat & Geographic Range

Canadian beaver

Habitat

Typically found in grasslands, forests, and vegetated habitats.

Range

Widely distributed across Europe (15 countries), North America (United States), and South America (Argentina, Chile).

Ray's Knotgrass

Habitat

Typically found in diverse terrestrial habitats from tropical forests to temperate regions.

Range

Distributed across Denmark, Norway, and Sweden. Currently classified as Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

Canadian beaver

The largest rodent in North America, Canadian beavers weigh up to 32 kg and are master ecosystem engineers inhabiting rivers, lakes, and wetlands across Canada and the northern United States. By felling trees and constructing dams up to hundreds of meters long, beavers create ponds that provide habitat for hundreds of species. Their lodges and canals transform entire watersheds. Once nearly hunted to extinction for their fur, beaver populations have recovered strongly.

Shared Countries

Both species can be found in 2 countries:

🇳🇴 Norway 🇸🇪 Sweden