American Beaver
Castor canadensis
American Beaver (Castor canadensis) — Nature’s Overachieving Wetland Architects
The American Beaver (Castor canadensis) is North America’s largest rodent and a playful ecosystem engineer that builds dams, lodges, and wetlands with nonstop energy and impressive skill.
- Habitat
- Ponds, lakes, rivers, streams, marshes with woody vegetation
- Size
- 2–4 ft long plus 10–12 in tail; 35–65 lbs
- Diet
- Bark cambium, leaves, buds, aquatic plants
- Range
- Most of North America except arid Southwest and southern Florida
- Conservation
- Least Concern; rebounded after historical overhunting
Habitat & range
Picture a busy engineer with a flat tail and a mission: the American Beaver thrives across most of North America, from Alaska and Canada down through the lower 48 (skipping the driest deserts and southern Florida) into northern Mexico. These semi-aquatic rodents love slow-moving freshwater—ponds, lakes, rivers, streams, and marshes—where woody snacks grow right along the banks. They turn ordinary waterways into deep, protected ponds that become bustling wildlife neighborhoods.
Diet & foraging
Strict herbivores with a serious wood habit, American Beavers chew the tasty cambium layer under bark from willow, aspen, poplar, birch, maple, and alder. They also munch leaves, buds, roots, and aquatic plants, holding food in clever front paws like tiny lumberjacks on break. Their iron-rich orange incisors never stop growing and stay razor-sharp for felling trees. Come winter, they cache branches underwater in a natural fridge so dinner stays fresh under the ice.
Behavior & adaptations
American Beavers are master builders and devoted family types. They stack sticks, mud, and rocks into watertight dams, then craft cozy dome lodges with underwater entrances that keep everyone safe and dry. A loud tail slap on the water serves as the ultimate “predator incoming!” alarm. Mostly nocturnal or crepuscular, they swim up to 5–6 mph, hold their breath for 15 minutes, and use built-in goggles plus closable ears and nostrils. Monogamous pairs lead tight colonies of up to eight, even digging canals to float logs home like nature’s own log drivers.
Ecological role
These rodents are genuine keystone species whose dams create wetlands that boost biodiversity for fish, frogs, birds, and bugs while fighting erosion, filtering water, and easing floods. American Beaver appears as a Mammalia creature card in Wilder TCG. Their landscape-scale remodeling helps entire ecosystems stay healthy and resilient.
Fun facts about American Beaver
- Iron in their enamel turns teeth bright orange and makes them self-sharpening chainsaws.
- Some beaver ponds are so big they show up on satellite photos from space.
- They can swim 5–6 mph and stay underwater 15 minutes—longer than most humans hold their breath.
- Beavers dig food-transport canals and stash branches underwater like a winter pantry.
- That flat tail works as rudder, balance beam for carrying logs, and built-in drum for danger alerts.
American Beaver vs Platypus
The larger, powerfully built beaver drives off the smaller platypus with its sharp incisors and strong swimming ability.
In a quiet freshwater stream where their ranges might overlap, the beaver spots the platypus foraging along the muddy bottom. The platypus relies on its sensitive bill to hunt small invertebrates and its venomous ankle spurs for defense, but it is far lighter and less equipped for direct confrontation.
The beaver, with its broad flat tail and chisel-like teeth suited for felling trees, slaps the water in warning before advancing. Its larger size and ability to stay submerged longer give it the edge in this shared aquatic habitat.
The platypus retreats to avoid injury, leaving the beaver to continue its dam-building undisturbed.
Mammalia · Water · Cost 2
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