Urban expansion, agriculture,
logging, mining, hydroelectric development,
oil and gas exploration and increased recreational
use of the back country have all caused a loss
of the grizzly habitat and have placed these
magnificent creatures at risk. Habitat loss
has a most devastating effect on the grizzly
because of two factors: they require a home
range up to several hundred square kilometres
and they have a very slow reproductive rate.
In the US, it is estimated
that fewer than 1000 grizzlies still survive
in a habitat reduced by 99% due to human encroachment.
In Canada, their habitat is either lost (24%),
threatened or at risk. BC's wilderness already
has approximately 200 000 kilometres of roads
that increase access to hunters along the bears'
travel routes.
In alpine and sub-alpine areas,
increased cattle grazing within prime bear habitat
disrupts their spring and fall feeding sites.
Oil and gas exploration involves surface trenching,
access roads, seismic lines and transmission
lines; in northwestern BC, for example, 13 000
square kilometres of seismic lines and transmission
lines led to the extirpation of grizzlies from
the Sikanni-Beaton Plateau.
Damage to river ecosystems
by hydroelectric dams and to prime habitat by
ski resorts and snowmobile and ATV trails is
irreparable. Coastal bears are highly dependent
on old-growth forests - the same areas most
valued by the logging industry. Logging has
also been cited as the cause of the loss of
140 wild salmon stocks and the presently at
risk designation of 624 others, the most
critical food source for the coastal bears.
Most types of human progress tends to silt the
rivers, create noise that alters the bears'
behaviour and produce roads that lead to bear/vehicle
fatalities when bears are attracted to the berries
and shoots that spring up in the cleared spaces.
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