Canadian beaver vs

Castor canadensis compared with Chrysosphaerella brevispina

Taxonomic Classification

Rank	Canadian beaver
Kingdom	Animalia (Animals)	Chromista (Chromista)
Phylum	Chordata (Chordates)	Ochrophyta (Ochrophyta)
Class	Mammalia (Mammals)	Chrysophyceae (Chrysophyceae)
Order	Rodentia (Rodents)	Ochromonadales (Ochromonadales)
Family	Castoridae (Beavers)	Paraphysomonadaceae
Genus	Castor (Beavers)	Chrysosphaerella
Species	Castor canadensis	Chrysosphaerella brevispina

Conservation Status

Canadian beaver

NE — Not Evaluated

Population: ~15.0M

Trend: Stable →

NE — Not Evaluated

Physical Characteristics

Attribute	Canadian beaver
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).

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Denmark, Norway, and Sweden.

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.

Chrysosphaerella brevispina is a colonial chrysophyte alga in the genus Chrysosphaerella, class Chrysophyceae. The genus is defined by its colonial organization: cells are arranged in spherical or discoid colonies in which each cell bears siliceous scales on its surface and projects stiff, spine-like silica bristles outward. The specific epithet brevispina (Latin: short spine) describes the relatively short silica spines that distinguish this species from congeners bearing longer projections. C. brevispina is found in freshwater environments, particularly in oligotrophic lakes and ponds of Scandinavia, where chrysophyte communities are richest. Chrysosphaerella species, like other chrysophytes, thrive in cold, clear, soft-water habitats and are sensitive indicators of water quality. The silica spines and scales produced by Chrysosphaerella cells are preserved in lake sediments as microfossils, providing paleoenvironmental records stretching back thousands of years. The spines may function as anti-grazing structures, reducing ingestion by zooplankton. The species has not been evaluated for conservation status by the IUCN and is listed as Not Evaluated. Its ecology and distribution in lakes outside Scandinavia are incompletely documented.