Table 2.
Estimates of population size, number of colonies, total surface area of beaver ponds (km2), and length of riparian interface created (km) through beaver pond formation for the different species of beaver and geographic regions as of 2000. Where only a minimum is provided, it represents a single (best) estimate for the population
| Region | Species | Population | Colonies | Pond area | Riparian interfacea | |||
|---|---|---|---|---|---|---|---|---|
| Min | Max | Min | Max | Min | Max | Range | ||
| Tierra del Fuego | C. canadensis (introduced) | 95 000 | 168 000 | 26 600 | 100 | 186 | 2160–4010 | |
| North America | C. canadensis (native) | 9 600 000 | 50 400 000 | 2 400 000 | 7 200 000 | 9280 | 41 210 | 204 000–908 000 |
| Eurasia | C. canadensis (introduced) | 13 000 | 2160 | 3240 | 8 | 19 | 180–420 | |
| Eurasia | C. fiber (native) | 683 000 | 137 000 | 228 000 | 106 | 821 | 2340–18 900 | |
aEstimates for riparian interface are constrained according to minimum and maximum estimates of other parameters but assume a circular pond shape and, therefore, represent a minimum range