| Type | Large, semi-aquatic rodent |
| Habitat | Rivers, lakes, wetlands |
| Species | |
| Threats | Overhunting • Habitat loss |
| Native range | |
| Ecological role | Wetland habitat creator and maintainer |
| Scientific name | Castor canadensis |
| Conservation status | Widespread, with some conservation concerns |
The North American beaver (''Castor canadensis'') is a large, semi-aquatic rodent native to the rivers, lakes, and wetlands of North America and Central America. Slightly larger and more adapted to an aquatic lifestyle than the beaver found in our timeline, this species is a keystone component of the region's ecosystems and has had a profound impact on human history and culture.
North American beavers are the second largest rodents in the world, reaching lengths up to 1.5 meters (5 feet) and weights of over 30 kilograms (70 pounds). They have a distinctive broad, flat tail and webbed hind feet for swimming. Their thick, waterproof fur ranges from yellowish-brown to nearly black in color.
Adaptations for their aquatic lifestyle include:
North American beavers are also excellent builders, constructing elaborate dams, canals, and lodges from felled trees and mud. These structures create and maintain the wetland habitats that are essential to the species.
The North American beaver is found across most of Canada, the contiguous United States, and portions of Central America, having expanded its historic range significantly compared to the beaver in our timeline. It is absent only from the Arctic tundra, the southernmost Mexican states, and a few isolated desert regions.
Precise population figures are difficult to obtain, but estimates suggest there are over 100 million North American beavers, making them one of the most numerous large mammals on the continent. Their populations were once much higher, but intensive hunting and trapping by humans in the 18th-20th centuries led to significant declines in many regions.
As a keystone species, the North American beaver plays a vital role in shaping the ecosystems it inhabits. By building dams that flood surrounding areas, beavers create and maintain diverse wetland habitats that support a wide variety of other plants and animals. Their activities:
The dams, canals, and lodges constructed by beavers also provide important resources and shelter for many other species, from birds nesting in their abandoned structures to wolves, bears, and other predators taking advantage of the fish and other prey found in beaver ponds.
North American beavers have long held great economic and cultural significance for the indigenous peoples of the region, who revered the animal's ecological role and valuable fur, meat, and other resources.
The arrival of European colonists in the 16th-18th centuries led to an explosion of commercial beaver trapping and hunting, as the animals' dense, waterproof pelts were highly prized in the lucrative fur trade. This resulted in dramatic population declines across much of the beaver's range.
Today, beavers remain an important game animal and nuisance species for landowners, as their prolific dam-building can sometimes conflict with human infrastructure and agriculture. Regulated hunting and trapping, as well as relocation programs, are used to manage beaver populations. However, habitat loss and fragmentation from human development remain the primary threats to the species' long-term survival.
While still considered a Least Concern species by the IUCN due to its large overall population, the North American beaver faces growing conservation challenges. Localized populations have been extirpated in some regions, and the species is considered threatened or endangered in a number of U.S. states and Canadian provinces.
Efforts are underway to protect and restore beaver habitat, reintroduce the species to areas where it has disappeared, and better manage human-beaver conflicts. But the North American beaver's future remains uncertain as it contends with the pressures of deforestation, urban expansion, climate change, and continued intensive hunting. Maintaining healthy beaver populations will be crucial for preserving the diverse wetlands they help create and sustain across the continent.
