Man: Human beings relate to bears
a lot more profoundly than they do
to most other species,
and the reason is because
we have so many similarities.
They're roughly our size,
they're very intelligent,
they eat the same foods that we do,
and they compete with us,
and that's an unusual situation.
I think when you're looking
face to face with a bear
you can recognize that cognition
going on behind the eyes.
That bear is calculating things,
trying to decide who you are
and what you're going to do,
whether he's gonna go back to eating
or turn around and run or charge you.
[Sniffing]
Man: People are either terrified of bears
or think they're cute and cuddly,
and they're somewhere in the middle.
They spend the majority of their lives
looking for food,
and that's their major goal in life
is to get as much food as they can
on a daily basis,
you know, sort of in preparation
for this long period of time
when they're not gonna have any,
and the drive is just so deeply rooted,
such an instinct for them.
Woman: Bears are very well-equipped
to find food.
I mean, they are perfectly
adapted to this.
They've got wonderful sense of smell.
They've got a pretty good sense of sight,
and they've got a good sense of curiosity,
so they will not only remember
where they found food sources before,
but they'll investigate
where they believe there might be food.
Leahy: They're just an incredibly
powerful animal.
Their claws are prefect for
ripping into things.
Really have great dexterity.
Prehensile lip allows them to grab
individual ants off of logs
and fish little acorns out of their cups.
Graber: What it means is that they
can have a very complex diet
because they have the mental capabilities
of testing all kinds of different
foods for their quality,
as well as recording geographically
where different foods are
at different times of the year.
So they can develop a really complex
seasonal map of where to go to find foods.
[Indistinct chatter]
Leahy: So where we get into
the conflict with people is you have
4 million people a year, up to 500 bears
or so in the park.
Every single person that comes in
brings some tasty camp food,
and they're cooking it nonstop
in the campgrounds,
and people drop a lot of food scraps,
and there's a lot of trash
and refuse and waste that comes
from all these visitors.
Mazur: When Yosemite became
a national park, slowly but surely
the interaction between human and bears
picked up because at the time
there was no way to store human food,
there was no way to store trash.
Garbage bags hadn't even been invented yet.
There were just dumps everywhere.
Bears quickly learned that they'd
come around humans
and they would get food.
Graber: In the period from the 1920s
to World War II, the bear parks
developed feeding areas that
were places where they could dump trash
and put stands up and people could
sit and watch bears.
Mazur: And so as an attraction,
it was very popular.
As a way to reduce human-bear conflict,
it actually backfired because
what they ended up doing was creating
more and more conflicts
between humans and bears,
creating more of what they
were calling nuisance bears
because they had become conditioned
to using human food and habituated
to the presence of humans.
Leahy: 1972, the last dump was closed,
so now these giant food sources
are just removed, they're gone,
they're not available for bears,
and you have food-conditioned
habituated bears,
and there's a lot of them now.
Graber: And the result was
the same everywhere.
If the bears weren't gonna get the food
at the end of the food chain,
they were gonna simply move up the line
and go into the campgrounds
and take the food directly from the source,
and that's what happened.
So when I arrived in Yosemite Valley
in '74, it was chaos.
It was simply chaos,
and it looked like a madhouse.
Mazur: They could flip trashcans open,
they'd peel back the windows on cars
and enter into cars,
and they did what they needed to do
to get food because that's what
they had learned.
They had learned that humans were
a source of food,
human vehicles were a source of food,
human buildings, and so they were
just doing what they had learned how to do.
Graber: The only solution to the problem
short of killing all the bears is
to make that food unavailable,
and ultimately, that led to my suggestion
that the park experiment with
heavy plate steel lockers
big enough to stick a cooler in
and to put those in campsites.
Turned out to be very complex
and very expensive,
but in 1977, the Park Service tried it
at White Wolf Campground in Yosemite.
Every single site had a locker,
and a rather scary patrol ranger
went through the campground right
at dinnertime and told everybody
to put away their food in the lockers
or else.
Leahy: Every single site in
Yosemite National Park has
a food storage locker that people can use
so they can get their food out
of their vehicles, out of their tents,
and store it in a place where bears
cannot obtain it.
So we spend a ton of our time going out
and educating the public,
going around and making sure everybody
who's visiting the park is aware that
"Hey. If you leave your food out,
"there's a good chance a bear
"might get it, and it's gonna change
"that bear's life forever."
Mazur: Once they learn
that they can get food from humans,
they've learned it.
They're not gonna forget it,
so that information is available to them,
and so what was a wild bear
foraging out on wild lands now becomes
a bear that we're gonna have
these conflicts with.
Graber: The bears that are successful
at obtaining human food then change
their entire regime.
They learn that aggression,
which is, by the way, mostly
fake aggression,
is a really good tool to scare
people away from their food
if they won't leave.
You know, a bluff charge is
a really impressive thing.
Woman on video: [Bleep] Oh, God. Ohh.
Graber: And then we have now
created a monster that we really have
no choice but to destroy.
I think living with black bears
in national parks is gonna require
constant vigilance and management.
There are chores in this world,
and one of them is the chores
of managing food so that we can
live with bears.
Leahy: This park is here to
protect those animals.
This is their place.
This is where they belong.
Mazur: Everyone has a chance to be part
of the solution.
Everyone has a chance to contribute
to making this a better place,
a wilder place, a more stunning place
that will last into the future.
Everyone has that chance.
Graber: If we do a consistent job
of managing human food and making it
largely unavailable to the black bears,
we can live with them.
They're exciting, they're handsome,
they're fascinating to watch,
and I think we can live with them
very well in national parks.