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[News clip] The rain has been coming down all day...
Throughout the winter,
storms blowing in from across the Pacific Ocean
hit Vancouver Island on the western coast of North America,
enveloping it in rain and near constant humidity.
These storms help give rise to giants,
centuries old trees that defined the old growth forests of the region.
But these damp winters present a challenge for animals
looking for a dry place to hibernate.
For one of the forest inhabitants,
the answer lies in the forest's odest trees.
Black bears are vital to the health of coastal ecosystems in the Pacific
Northwest. In the spring through fall, they spread seeds and nutrients
from the variety of foods they eat throughout the forest,
enriching trees and plants.
In the winter, when food is scarce, bears hibernate in the safety of dens
where mothers will raise cubs for the first few months.
Helen Davis has been researching this critical period for the last 30 years.
Black bears in the western coast of North America all use very similar
types of dens, which usually involve large, old growth trees.
With such wet winters and no consistent snow cover for insulation,
the hollow insides of trees, and the cavities they create
when they fall, make the perfect den sites for coastal black bears.
We started looking at black bear denning because it had become a concern
with industry that perhaps logging was in conflict with the supply of bear dens.
So if we understand the structures that black bears need to survive
the winter denning period, then hopefully those dens will eventually be protected.
If you just try and find a den,
like get up in the morning and go, Oh, I would like to find a bear den today,
you know, it's just not going to happen.
They are very, very rare.
I call them the unicorns of the forest.
We drive resource roads and logging roads.
Some of the sites that that we'd like to get to are hard to access.
People just randomly send me emails and photos and stuff
when they find a bear den because they know me as the bear den lady.
Right now, I'm trying to see if an infrared camera
can pick out the warmth of a bear up inside the tree to tell
if a bear is in a den or not without actually disturbing it.
There, we're seeing a bright spot.
Every time I come down, there's a light spot
right here., quite distinct.
There's kind of a hot spot, it looks like, on the side of the tree.
It looks a little bit exciting.
So I'm going to get a trail camera now and put it up to see
if I can get some footage of a bear leaving this spot in the spring
that would maybe confirm that we did indeed see a hot spot in the tree.
Wildlife trail cameras are super frustrating.
They are very finicky,
and the fact that
you're trying to purposely put them, in my case,
in places with bears means, that bears encounter them a fair bit. And
bears have ruined
a number of my cameras.
Bears being bears.
But you also get really
awesome, cool footage of bears doing really awesome, cool things.
At one den we caught footage of a female and cub gathering,
bedding. They piled up so much vegetation like it was just this massive pile.
They can make incredible thick nests like a couple of feet deep.
So I've had a lot of insight from the trail camera footage.
[Gasp] Female with cub.
I wonder if it's the one that was here last winter.
Another squirrel.
Oh, cougar. Nice one.
Cougars are a potential predator for bears in their dens.
So this isn't a very safe den, really.
It opens right into the den chamber.
So that's a big concern of why I'm trying to get good bear dens protected.
The trees that are suitable for dens are incredibly rare,
even within old growth, and it takes hundreds and hundreds
of years for them to form.
Black bear dens are not currently protected against forestry
practices on Vancouver Island and most of the B.C. coast.
When these regions are logged,
den trees can be cut down or left as a lone tree in a clear cut,
leaving a female and cubs with no cover to use to escape predators
in the vulnerable period after they leave the den.
Historically, 80 per cent of highly productive forest
ecosystems on Vancouver Island are expected to have been old growth.
It now makes up just 3 per cent of these ecosystems.
Second growth is then cut down before
trees can grow large enough to support new dens.
As we log the last old growth, we are losing some of the last dens.
We aren't replacing those structures right now.
The trees and second growth forests are being harvested
at much, much smaller diameters then can make new dens.
We thought we'd try making artificial bear dens
because the natural structures haven't been protected.
I worked with an industrial designer and created what we call the den pod
that mimicked the exact dimensions that bears like to use.
The bear is meant to come in through the entrance
and then turn and use this area as the den chamber.
It's about 110 centimeters across, which is exactly the right size
for a female bear.
We have the entrances about 30 by 35 centimeters.
I can get in and out of it, but I'm not very happy doing it,
which is usually just about the right size for a female bear den entrance.
And then we would pile woody debris on top
and especially all around the edge to make it kind of look more natural.
So we put ten of those out and the cameras, did show quite clearly
that the bears quite enjoyed the things we had put out for them.
They like to stand on them, but they really like to slide on them.
I don't think they really encounter smooth things in their environment very much.
But none of them got used as as dens.
I've made artificial bear dens
out of old cedar stumps in a few places, and
we had a little bit of success with that in that one stump
that we cut an entrance into and put a plywood cap on top
has been used by a bear for the last four winters in a row.
Though the dens made from old stumps have been used by bears,
modern forestry practices cut trees much closer to the ground,
leaving no stump to modify.
And since the plastic structures weren't denned in,
Helen is concerned that new dens cannot simply be fabricated.
I've been studying bear denning for, it's been 30 years now,
and everything from my master's thesis in the early nineties to an artificial,
bear den study for the last seven years, over and over again
we just keep seeing the same thing, which is the need for large,
old growth structures as winter den sites for coastal bears.
It's very clear that this is what is needed for these animals
to survive and reproduce.
It's about time that regulation comes into effect to protect dens.
Retaining these large old growth trees
is critical to maintaining coastal bear populations.