NARRATOR: Badlands National Park, South Dakota,
244,000 acres split into two dramatic worlds, the Rocky
Badlands themselves, carved out of the ground by wind and rain,
and beyond them, an ancient sea of grass,
home to the icons of the Old West.
This land has a long and deep connection
to the indigenous peoples of America.
It's the current and traditional land
of the Oglala Lakota tribe.
For 12,000 years, people have used these lands,
but prairie dogs have been here even longer.
A female black-tailed prairie dog
lives on the grasslands in a family
group known as a coterie.
In spring it's time for her to start a family.
After mating, she maintains her burrow
and collects nesting material.
In doing so, she becomes an ecoengineer.
Her constant gardening benefits over 100 species.
In the sprawling sea of grass, the prairie dog town
is an island of life, drawing in species from far and wide,
including predators.
Prairie dogs are the perfect snack for the coyote.
The female's quest to start a family
could be over before it started.
She's completely oblivious to the threat.
However, the prairie dog has allies.
[CHIRPING]
Her neighbors are on high alert.
[CHIRPING]
Each prairie dog town comes with its own built-in alarm system.
[CHIRPING]
It's one of the most complex animal
languages ever decoded, with specific calls
for different threats.
The coyote is spotted.
And short chirps call him out.
[CHIRPING]
He literally has nowhere to hide.
With the threat gone, they give the all clear signal--
[YIPPING]
--a jump yip.
The key to thriving in the badlands
is looking out for each other.