How to identify it
Large semi-aquatic rodent, body 47–61 cm plus a 37–41 cm tail; up to about 9 kg. [1][2]
Light to dark brown fur; long, round, sparsely haired tail. [1][2]
Conspicuous white whiskers and prominent incisors on a large, nearly triangular head. [1][2]
First four toes of the hind feet webbed, the fifth free. [1][2]
Compared with the beaver: Beavers have a broad flat tail and fully webbed hind feet. [1][2]
Compared with the muskrat: Muskrats are much smaller with a short side-flattened tail and unwebbed toes. [1][2]
Species it is confused with
Check these before deciding what you are looking at. If you are not certain what it is, do not shoot.
- North American beaver · Castor canadensis
- Muskrat · Ondatra zibethicus
Where it lives
Fresh marshes preferred, but also bayous, rivers, impoundments, farm ponds, canals, swamps and brackish or salt coastal marshes. [1][2]
How it behaves
Mostly nocturnal, peaking near midnight; more daytime activity when food is scarce [1][2]
Where it is listed for removal or nuisance take
These authorities list this species as nuisance, invasive or unprotected wildlife that may be taken. This is not a game season.
Where legal take is listed
- British Columbia — hunting, invasive species removal · 2026-2028 Hunting and Trapping Regulations Synopsis
- Alabama — hunting, trapping · Beaver, Nutria, and Groundhog Seasons 2026-2027 (ADCNR)
- Arkansas — hunting, trapping · 2026-27 Arkansas Hunting Guidebook (PDF)
- Delaware — invasive species removal, trapping · 2026-27 Delaware Hunting & Trapping Guide: Furbearer Trapping & Hunting
- Florida — hunting, nuisance or unprotected take, trapping · Other Wildlife Regulations (FWC)
- Louisiana — hunting, invasive species removal, nuisance or unprotected take, trapping · 2026-2027 Louisiana Hunting Regulations (updated Aug 7, 2026)
- Mississippi — hunting, nuisance or unprotected take, trapping · Nuisance Species Regulations (MDWFP)
- Missouri — trapping · A Summary of Missouri Hunting and Trapping Regulations 2026
- New Mexico — hunting, invasive species removal, trapping · 2026-2027 New Mexico Hunting Rules & Information (v08.11.26)
- Oklahoma — hunting, trapping · Furbearer/Coyote Regulations
- Oregon — hunting, invasive species removal, trapping · Oregon Furbearer Trapping & Hunting Regulations, July 1 2026 - June 30 2028
- Texas — hunting, trapping · Outdoor Annual: Seasons & Bag Limits: Fur-bearing Animals
- Virginia — nuisance or unprotected take, trapping · Furbearer Trapping Regulations and Seasons | Virginia DWR
Being listed is not an open season. Seasons, zones, licences, methods and limits decide whether this animal may be taken on a given day and place — check Hunt or the authority before you go. Listings read 2026-09-30.
Where it is found
Native to southern South America. Introduced in Louisiana in the 1930s and spread widely; now in the southeastern and south-central U.S., Oregon, Washington, Maryland and other states, with records in British Columbia.
Sources
Every claim above is attributed to one of these published sources.
- BIOLOGICALMyocastor coypus - Species Profile
U.S. Geological Survey Nonindigenous Aquatic Species · reviewed 2026-09-30
U.S. Geological Survey Nonindigenous Aquatic Species
- BIOLOGICALMyocastor coypus (NatureServe Explorer)
NatureServe · reviewed 2026-09-30
NatureServe