 In addition to population estimates of actual animals, it is also possible to relate habitat quality to population abundance. An inherent threshold or optimum number of bears which can be supported, is calculated for every unit of bear habitat in BC, known as the habitat carrying capacity. Such high quality habitats as rich salmon rivers or extensive  huckleberry patches are capable of supporting greater numbers of Grizzly Bears than habitats like arid grasslands.Best Method in North America In BC, a sophisticated method is used for mapping Grizzly Bear habitat by identifying the location of high quality habitats which are rich in bear food and other ecological requirements. This method (Fuhr-Demarchi Method) is the most highly evolved in North America for hierarchically categorizing wildlife habitat. The Fuhr-Demarchi Method is being exported to the US and has been found to be more accurate than the very generalized mapping in use in most areas outside of BC. The Fuhr and Demarchi Method Explained The objective of this mapping method is to estimate the land's capability for supporting GrizzlyBears. Based on research in BC and other areas in North America, this method was originally designed for Grizzly Bears. It has been improved over time for Grizzly Bears and other species. Habitat units are combined with biogeoclimatic vegetation zones to produce a very detailed map of habitat capability. Habitat units are mapped for a large number of factors including soils, aspect, moisture, vegetation, and terrain features such as floodplains and avalanche tracks. Habitat units (from a few hectares to several hundred hectares) are ranked from nil to very high according to their potential degree of use by Grizzlies, based on the extensive experience of bear and habitat researchers. Step Down Process of Population Estimation Field surveys confirm habitat quality and current use by Grizzly Bears. A "step down" (reducing numbers) calculation is made to reduce the potential for Grizzlies due to present land-use activities such as grazing and logging, cultural activities such as hunting and human-bear conflicts and the impacts of habitat loss through alienation and fragmentation. Once these factors have been taken into account, a final population estimate is reached.
This habitat methodology, in combination with population estimates, provides an accurate picture of whether bears are present in particular areas, as well as answer to whether there is sufficient habitat to support their numbers. |
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 "The public should know that...over much of their range, [Canadian Grizzly bear] populations remain healthy." (1999 Report by the World Conservation Union Bear Specialist Group) |
