| Summary: | The focus of the study was on the influence of transportation corridors (Tcorridors),
which included the Trans-Canada Highway (TCH), Canadian Pacific Railway,
and Highway 95, on the distribution and habitat use patterns of black and grizzly bears
near Golden, B.C. The relationship among bears, habitat, and T-corridors was examined
using compositional analysis and univariate comparisons in conjunction with a
Geographic Information System. During 1994-1997, 40 radio collared grizzly and 24
radio collared black bears were located 1061 and 505 times, respectively. Because the Tcorridors
followed major valleys and crossed a mountain pass where slide chutes and
riparian areas predominated, I expected bears to be displaced from these habitat types
during spring. During spring, 85% of all collared grizzly bears used areas adjacent to Tcorridors
less than expected by random use. The habitat analysis further revealed that
although slide chutes were selected the majority of bears selected chutes adjacent to
corridors less than expected, however, 15% of the radio collared individuals used slide
chutes adjacent to T-corridors more than expected. These bears were all among those
trapped within a home range radius of the T-corridors and only one of these 6 bears was
an adult female. Eighty-eight percent of collared black bears used areas within 500 m of
the corridors during the spring. At this time both male and female black bears selected
right-of ways and timbered areas more than expected. Use of the rights-of-way increased
the black bears' risk of mortality. To reduce mortality of black bear and return bears to a
more natural diet, vegetation along the rights-of-way should be replaced with less
palatable plant species. Because of the potential for habitat and population fragmentation
among the grizzly bears, areas where bears cross the corridors should be identified before
the TCH is twinned. If possible, portions of the highway that contain such crossing areas
should be protected from further development. If development must proceed, areas along
the T C H which have the potential to act as crossing-underpasses for bears should be
enhanced to encourage bear use and improve conductivity.
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