Evaluation of a model bear viewing programme at Glendale River with policy recommendations

The Pacific mid-coast region of British Columbia has a mild, hypermaritime climate that places its biological productivity in the range of tropical rainforests. The low elevation river valleys are characterized by rich alluvial soils, further enriched annually by upstream nutrients flooding over the stream banks of the floodplains and distributing rich silt to the roots of giant Sitka spruce and Western hemlock forests. Unique to Canada's rivers flowing into the Pacific (but not north into the Mackenzie River, for example) are the massive contributions of nutrients from the bodies of 5 species of anadromous salmonids. This flux of organic matter has long been recognized as essential to the production of young salmon but the additional fertility increment to riparian and upland forests is currently under intense investigation (Bilby et al. 1996; Cederholm et al. 1989; Willson et al. 1998). The role of migratory salmon in supporting dense populations of grizzly bears has recently been demonstrated for a large sample of coastal bears in Alaska (Miller et al 1997). A strong statistical correlation between the per cent of meat, mainly salmon, in the diet and bear density (Hilderbrand et al 1999) confirmed earlier speculation by Miller et al. (1997) that Alaskan's most dense bear populations also had high salmon diets and were among the most dense on a world-wide basis.
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\nGrizzly or brown bears on the coast of British Columbia and Alaska are the same species as the grizzly bears of the Rocky Mountains. However they are much bigger and have higher population densities because of abundant of salmon (Hilderbrand et al. 1999). Alaska population densities vary from a maximum of 550 bears /1000 sq. km in Katmai National Park where salmon are seasonally available to less than 5 for mountain bears of the eastern Brooks Range on a marginal food base (Miller et al. 1997). Coastal Alaskan bears forage widely for fish. At Brooks River in Katmai National Park & Preserve bears feed on sockeye salmon starting in late June as soon as they enter rivers to spawn. Hundreds of bears have daily access to salmon when the salmon are rich in fat, a fuel used to ascend rivers, build redds, mate and defend their nests against others. Bears feed on these fish which have 50% of their caloric value in fat. From Katmai's Brooks falls bears migrate with the fish to their spawning beds and, later, back to the stream mouths where the dying fish are again consumed in prodigious numbers. The end result of this movement is a pattern of deposition of fish pieces and feces over the landscape. Studies in the state of Washington of the fate of salmon carcasses showed that 22 species of mammals and birds carried salmon pieces into the forest (Cederholm and Houston 1992). The nitrogen in the fish parts and bear feces is incorporated into plants and animals in the forest and in the streams therefor enriching the ecosystems there. Bears are one of the largest contributors because of the massive amount of material that they consume and the great distances that they move.
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\nMany of the Alaskan sites with the highest bear densities have become popular, and profitable, tourist destinations. More recently a bear viewing/eco-tourist industry has begun to develop in British Columbia. In March 1998 bear viewing policy and guidelines were presented in which the government expressed support for the use of bears for tourism. This study addresses the impacts of viewing on bears and presents recommendations for further research and the sustainable development of bear viewing in the province.

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