(rustling) ♪ ♪ TEVIN: Ferrets, they really need someone to take care of 'em.

Conservation wise we need to save these animals.

(rustling) ♪ KRISTY: I think recovering ferrets, recovers something in ourselves.

Bringing a piece of the prairie puzzle that's been missing for many, many years (footsteps) back into place.

WES: I just like being part of something that's bigger than myself.

Something that helps us bring back a species that was almost extinct.

♪ (cow mooing) KRISTY: The prairie ecosystem, it's teeming with wildlife, from pronghorn to bison, swift foxes, (chirping) burrowing owls.

The grasslands to me are "prairiedise."

The whole ecosystem works together to support what is the heart of North America and the bread and butter basket for our country.

♪ NARRATOR: But beneath waves of prairie grasses lies an unlikely story of extinction, resilience and second chances.

KRISTY: We call 'em the masked bandits of the prairie.

(bird chirping) NARRATOR: At the heart of that story: two once abundant animals with deeply intertwined histories: the prairie dog - and the black-footed ferret.

(bird chirping) The black-footed is the only ferret native to North America.

♪ KRISTY: Black-footed ferrets are really cool, rowdy prairie predators.

And they are an integral part of the ecosystem to balance that delicate dance that keeps predator prey cycles in check.

NARRATOR: Their primary prey is the prairie dog a ground-dwelling relative of the common squirrel.

(prairie dog huffing) KRISTY: Prairie dogs are the Chicken McNuggets of the prairie.

They feed everything.

NARRATOR: A single black-footed ferret can eat over 100 prairie dogs a year.

Bobcats, swift foxes, and birds of prey eat them too.

(prairie dog chirping) But before they become dinner, prairie dogs serve another important function in the ecosystem.

They engineer multi- chambered burrows measuring up to 14 feet deep and 100 feet long.

(birds chirping) These burrows are often dug close to their neighbors, creating prairie dog towns that can span thousands of acres.

KRISTY: Out here on the prairie, shelter's found below ground, so animals like tiger salamanders, swift foxes, even rabbits, black- footed ferrets, rely on the burrow systems of prairie dogs for survival.

(prairie dog chirping) Without the prairie dog in that ecosystem, nothing else exists.

NARRATOR: With this outsized influence on their ecosystem, prairie dogs are a keystone species on the grasslands.

But early European settlers saw them as vermin - occupying land that could be used for agriculture and competing with cattle for grass.

(cow mooing) Shooting prairie dogs (gunshots) was common and in 1915, the government started a widespread poisoning campaign.

♪ To make matters worse, the prairie was hit by a non-native disease called sylvatic plague.

KRISTY: Sylvatic plague can kill an entire prairie dog colony within a matter of weeks.

It can also kill black-footed ferrets.

NARRATOR: Agriculture and development shrank the grassland by more than half, and the deadly combination of plowing, poison and plague wiped out 95% of prairie dogs.

(insect noises) Without them, the prairie ecosystem collapsed.

KRISTY: When we lost that prairie ecosystem, we lost ferrets too and that was pretty dire.

NARRATOR: Where once there had been a million or more ferrets, by the 1950s not one could be found.

Over the next 30 years, the species teetered on the brink.

Occasionally spotted, then presumed extinct.

(grass rustling) Until 1981, when a ranch dog in Wyoming brought home a ferret - and revealed a small population hanging on in the wild.

Conservation experts were mobilized, and a rescue effort for the species began.

KRISTY: They captured 24 animals out of that population (black-footed ferret chattering) to bring into captivity and thankfully it was successful.

NARRATOR: U.S.

Fish and Wildlife, the Smithsonian Zoo and zoos across North America urgently joined forces to start a breeding program.

(black-footed ferret chattering) Researchers cryo-preserved genetic material from founder ferrets, and even created the first successful clone of a U.S. endangered species, named Elizabeth Ann.

By 1991, the captive breeding program was so successful, Fish and Wildlife began returning ferrets to the wild.

Prairie dog numbers had rebounded enough to feed them and across the 1990s, nearly 1,200 ferrets were released.

The Aaniiih and Nakoda nations have long held a spiritual connection with the ferret.

And in 1997, at the Fort Belknap Reservation in Montana, they became the first indigenous people to reintroduce the black-footed ferret on their land.

(Joseph speaking Aaniiih) ♪ NARRATOR: But two years later, a new wave of sylvatic plague hit the reservation, wiping out the ferrets and most of their prairie dog prey, once again.

♪ Another 13 years went by before new tools to mitigate sylvatic plague, including vaccines, made another reintroduction attempt possible.

(insecticide being sprayed) KRISTY: All right.

NARRATOR: The tribes approached the World Wildlife Fund to help with the effort.

Biologist Kristy Bly answered the call.

KRISTY: The purpose is to line the inside of every prairie dog burrow in this colony to mitigate plague to advance ferret recovery.

(insecticide being sprayed) NARRATOR: The team dusts each prairie dog burrow with a waterproof insecticide that kills the fleas that carry the disease.

With regular dustings, the prairie dog population rebounded, and the grasslands were once again ready for the masked bandits' return.

(cars driving on grass) RANDY: Today is a blessed day for the reservation and for the people that work so hard (black-footed ferret chirping) to bring out endangered species, a black-footed ferret back to the reservation here.

NARRATOR: This time around, (black-footed ferret chattering) the tribe was taking no chances with another wave of sylvatic plague.

These ferrets and prairie dogs were not gonna be left to fend for themselves - but dusting alone was not a viable long-term solution.

KRISTY: Sylvatic plague is the single largest threat to the recovery of black-footed ferrets today.

(insecticide being sprayed) If you think about covering all this area on foot, all these burrows, it can take weeks to do that.

We need to scale up our ability to protect them from plague in ways that are more cost efficient and labor friendly.

NARRATOR: There's no shortage of ideas.

Experts are developing a host of creative strategies to fight plague in both ferrets and prairie dogs.

First, flea killing agents disguised as the perfect snack for a prairie dog.

KRISTY: Peanut butter flavored "fipbits", is what we call them.

NARRATOR: Using ATVs, (ATV driving) field teams can treat about 50 acres per hour.

And areas inaccessible by ATV are handled by bait-loaded drones that can drop a pellet a second.

(pellet being dropped) "Fipbits" have the power to protect prairie dogs from plague for up to two years - (Prairie dog chattering) and the pellets will soon be used at prairie dog towns around black-footed ferret sites across North America.

Because when you save the food, you take an important step to saving the ferret.

♪ But the teams also need to directly protect the ferrets themselves.

(rustling) (footsteps) KRISTY: We want to make sure that all wild born ferrets are also vaccinated against plague.

NARRATOR: At Fort Belknap, they estimate there are perhaps 20 wild-born kits and even more unvaccinated adults out on the prowl.

Vaccinating them is no easy feat.

KRISTY: Wait, let's talk about who's going where.

TEVIN: If someone could do this north side and then someone can split down the middle on the south side of the road.

KRISTY: Okay, so a three-way.

♪ Black-footed ferrets are nocturnal and we must go out at night to look for them.

(car starting) Tonight, we have four teams out spotlighting and we have 3,500 acres to cover.

We have partnered with Aaniiih Nakoda College to help with monitoring this population of black-footed ferrets.

We wanted to make sure that we had students learning and leading this project from the very beginning.

DAWN: Aaniiih Nakoda is the name of the two tribes that make up Fort Belknap.

This is just my home, like this is where I'll probably always be.

I guess just keeping it intact.

(howling) KRISTY: Finding ferrets involves spotlights mounted to the roof of a truck, looking for their notorious green eye shine.

TEVIN: You'd be able to see 'em between 2:00 to 5:00 AM.

NARRATOR: If they're lucky.

The spotlight only works if the ferret is looking in their direction.

The Fort Belknap team also use thermal cameras, which can detect the heat signature of any warm-blooded mammal up to 1,500 feet away.

One is mounted on a tower.

The other goes airborne.

(drone flying up) KRISTY: We will be flying a drone mounted with a thermal camera, to see where ferrets are on the landscape.

NARRATOR: Technologist Shawn Jepson controls the tower-cam while ecologist Jesse Boulerice gives the team a birds eye view of the prairie.

They'll sound the alarm the moment they spy a ferret.

SHAWN: It sees heat instead of light and if a ferret sticks its head up, then we can see it.

JESSE: Can usually tell 'em apart by kinda their body movements.

They sort of bound up and down like a big slinky.

(drone flying) (horn) NARRATOR: Finally, their first ferret of the night.

(horn) SHAWN: Oh, I see him.

I see him.

♪ (buttons being pressed) JESSE: We have a confirmed sighting on a ferret.

I'll send you the coordinates.

TEVIN: Now, NARRATOR: As if finding the ferrets isn't hard enough, the ground team now has to trap it.

KRISTY: So, this time of the night, most of the black-footed ferrets are hunting prairie dogs so they are coming away from their home burrows in search of food.

Then we set the live trap down into the burrow, and we keep it covered so that it seems dark like the extension of the prairie dog burrow.

So, we're hoping that this is not his home burrow and he'll want to come out very quickly.

♪ NARRATOR: Tonight they're in luck.

TEVIN: Grab the reader, and the other marker.

NARRATOR: With the ferret safely in the trap, it's time for a handoff.

JESSICA: No she certainly does not.

NARRATOR: Kristy (chatter) and biologist Jessica Alexander (chatter) prepare to vaccinate the patient and implant a tiny tracker chip.

JESSICA: Thinking about it.

There she goes.

I keep her covered just to keep her stress levels down.

KRISTY: You're at two and a half minutes.

JESSICA: All right.

She's on the mask.

Kristy.

KRISTY: Okay.

(air flowing) Alright, I'm gonna give her the pit tag now.

NARRATOR: The pit tag is a tiny transmitter that gives each ferret a unique ID number.

JESSICA: From now on we'll be able to follow her through her lifetime out here on the prairie.

NARRATOR: Finally, the vaccine.

♪ JESSICA: I'm going to give her a dye mark here on her neck.

This way the spotlighters will be able to see that she's already gotten all our vaccines and won't have to come back.

Then, she's all done.

NARRATOR: Within minutes, vaccination is complete, and this young female ferret is awake and ready to be released.

SHAWN: And there it goes.

♪ Home sweet home.

NARRATOR: This season, the team vaccinated 22 ferrets at Fort Belknap.

Across the country, similar programs are helping wild ferrets thrive.

KRISTY: We estimate as of fall last year to be about 390 ferrets in the wild in North America.

NARRATOR: But this achievement goes well beyond saving a single species.

KRISTY: When you bring ferrets back, you've got a functional prairie ecosystem that's been missing for many, many years.

DAWN: This is really good experience for me, working with the black- footed ferrets and it just gives you hope.

(black-footed ferret chattering) (black-footed ferret chattering) KRISTY: My biggest hope for this species is that they are recovered.

We have the tools in order to do that, and we have the people committed to their recovery.

♪ ♪ ♪ ♪ ♪