You're watching Yellowstone InDepth.
(Hissing steam and trickling water
from Mammoth Hot Springs)
(Clark's Nutcracker call)
(Gurgling stream)
Shan Burson: It's been just a couple
decades that the National Park Service
has identified that natural soundscapes
are really important.
I think that's a big reason why I
was hired to work here at Yellowstone.
(Howling wolves, wind)
My name is Shan Burson, I'm a
bio-acoustic ecologist at
Yellowstone National Park.
Acoustic monitoring is just trying to
understand the soundscape of Yellowstone.
The approach that I'm taking is using
automated systems that collect sound
levels and digital recordings.
(Sound of equipment being set up)
So I'm setting up a new system here and
I've never used this microphone setup.
I've had one similar to this.
This is a stereo mic.
Make sure I have the right
channel heading north.
People have been interested in sounds
in parks for decades but it really
came to the forefront probably about
twenty years ago when people started
noticing mostly human-made sounds were
starting to impact people's experiences
and then there was a concern of what
it was doing to wildlife.
This is the heart of the system,
a digital recorder collects MP3s or
WAV files depending on what I want,
and I'm just gonna hook this
microphone right into this.
So this is a recorder that will
just do, I mean will be from
now on for the next thirty days, it will
just be continuously recording whatever
these microphones hear.
And what I'm trying to do is get an
understanding of what, what the different
sound sources in the park both natural
sounds as well as human-made sounds
and find out how much they can be heard,
and where they're heard...
All right. ...and more or less what the
effect is of especially the non-natural
sounds on the natural soundscape.
(Sound of snow being shovelled)
I've heard soundscape defined similarly to
a landscape, where a landscape is kind of a
viewshed of what you can see if you look
out over the land and a soundscape is
basically what you can hear if you're
in a particular place at a particular time.
(Rushing water)
(Grunting bison)
(Gurgling stream)
(Gushing water and singing dipper)
A natural sound is any sound that's not
made by humans, so all animals sounds,
biological sounds, insects, birds, mammals,
amphibians,
(Bald Eagle hollaring)
as well as physical sounds.
(Roaring waterfall)
Waterfalls, waves, thunder, those things
are all part of the natural soundscape.
(Coyotes yipping and howling)
Acoustic ecology is a relatively new
and emerging field. As we start to recognize
the role that sound plays in the survival
and reproduction of animals.
Most mammals vocalize. And many, many, other
species of different taxa vocalize and it's
a really important for their natural history,
for attracting mates, for repelling competitors.
They use their ears to identify by sound
where prey species are and prey species likewise
use sounds of predators to try to avoid them.
(Sound of footfalls in snow)
(Sound of a loud snowcoach passing)
Oversnow vehicles are vehicles that
transport people on the top of the snow,
on the snow surface.
(Snow coach sounds)
National Park Service in Yellowstone wanted
to know more about the impacts or the
effects of oversnow vehicle noise on the park,
not only on natural, the natural soundscape,
but on visitor experience.
(Snow coach roars by)
Visitors were starting to
complain about non-natural sounds,
and if we have a lot of non-natural sounds,
human-made sounds, it starts to really
restrict what a particular animal can
hear because these motorized sounds,
non-natural sounds, start masking communication.
(Sound of a car on road)
One of the satisfying things of working
here is that the data I'm collecting I
think personally is important but also
the park thinks it's important because
they have modified some of the winter
use plans for the managed use
based on data I've collected.
(Sound of snowmobiles)
At this point there's a restriction on the
maximum number of oversnow vehicles,
both snowcoaches and snowmobiles that are
allowed in the park each day.
(Sound of snowmobiles)
I just set up a sound monitoring system,
just south of headquarters in Mammoth,
with Canary Springs behind me.
I'm setting this system up for several
reasons, one is I wanted to get what the
visitor experience is in the Mammoth area
as well as road traffic sounds,
and so this site fit the bill quite nicely.
It's a beautiful, sunny day
in the middle of winter.
I think it's going to be a good site.
(Snow crunching under Shan's feet)
(River gurgling)
Yeah I would like to ask visitors to
take a short period of time and actually
listen, be quiet in a place, and still
and listen to the sounds of Yellowstone
and I think they'd be really impressed
and excited about what they hear.
(River gurgling and American Dipper singing)
Although many people don't come to Yellowstone
with the idea that, "Oh I can't wait to
get there to hear natural sounds",
that it makes a big impression on them
when they're here.
(River gurgling)
(Wind and coyotes yipping)