Bearing down on grizzlies

Here’s your weekly Science Matters column by David Suzuki with Faisal Moola.

Bearing down on grizzlies

Years ago, I was surprised to learn that a grizzly bear is protected in
the United States, but if it walks across the border into British
Columbia, it can be killed for sport. So we did a program on them for
The Nature of Things. I was amazed to see pictures from the 1800s of
immense piles of skulls from grizzlies that were slaughtered to make
room for early settlers on the prairies. Grizzlies were not just
mountain animals; they flourished on bison all the way across Canada to
Manitoba and south to Texas and California (where the only place you’ll
find one now is on the state flag)! Grizzlies need space – tagged
animals have been known to travel over hundreds of kilometres in a
season. But the cumulative impacts of habitat loss and fragmentation
from logging, mining, road building, urbanization, and other land-use
pressures have forced them into isolated patches of territory.

The U.S. Endangered Species Act lists the grizzly as “threatened”,
meaning it is in danger of becoming extinct. Grizzly bears in Canada
are ranked as “special concern” by Canada’s scientific committee on
species at risk (the Committee on the Status of Endangered Wildlife in
Canada, or COSEWIC) but remain legally unprotected. In the absence of
legal protection, they continue to be hunted unsustainably in B.C.
Government statistics show that 430 grizzlies were killed in the
province in 2007, and close to 11,000 have been killed since 1975.

Last year’s kill in B.C. was a record, something we only found out
when environmental groups, including the David Suzuki Foundation, were
able to pry the information from the government. Most of the bears –
about 88 per cent – were killed for sport. The rest were killed by
poachers and animal-control officers.

The B.C. government argues that the grizzly hunt is sustainable, but
the methods by which it estimates the numbers of bears are imprecise.
In fact, many leading bear biologists say the B.C. government’s numbers
– about 17,000 grizzlies – are high and that the number may be as low
as 6,000. When scientists and researchers are unable to determine
accurate population numbers, they often rely on the precautionary
principle to ensure sustainable management. This is the idea that when
potential risks exist, it’s better to be safe than sorry. In other
words, if we suspect that grizzly populations are imperilled, we should
stop killing them, even if we aren’t yet 100 per cent certain about the
existing population size or rate of decline.

Some might ask why we should protect the grizzly. After all, it’s a
large, dangerous animal that has been known to kill humans and
livestock. But the dangers are exaggerated: grizzlies tend to be more
afraid of than threatening to people, and their impact on livestock is
minimal. More importantly, grizzlies are essential components of the
ecosystems where they live. They help to disperse seeds and nutrients
throughout the forest, and because they eat both plants and animals,
they have a significant “top-down” influence on the food web. When
salmon are spawning, grizzlies carry the fish into the forests to eat
them, leaving much of the carcass behind. Those salmon remains feed
many other birds, mammals, invertebrates, and microorganisms, and the
nutrients in the rotting carcasses fertilize the surrounding trees.
It’s a marvelous story of interconnections and interdependence.

The B.C. government has made some progress in grizzly conservation
by setting aside some of its habitat, including the Great Bear
Rainforest, as protected areas. But even there, trophy hunting is
allowed, and many of the parks and protected areas are likely too small
and isolated to maintain the grizzlies’ long-term survival. For this
reason, the way we manage the rest of its territory is critical. As a
start, the B.C. government must suspend the controversial grizzly hunt,
as Alberta recently did, and must continue to protect large areas of
grizzly habitat from resource development, roads, and other human
pressures. British Columbia is unique in that grizzlies still inhabit
much of the province, even though they have been eliminated from almost
all of their historical territory across the planet. That means we have
a global responsibility to protect this iconic carnivore.