It's well after midnight on the South Dakota prairie and biologist Travis Livieri is on the hunt.
"These can be extremely elusive creatures," Livieri said. "Sometimes it's kind of like searching for a needle in a haystack."
Livieri shines a million-candlepower spotlight mounted on top of his pickup truck into the darkness, sweeping the beam of light left and right.
Then suddenly, about 100 yards away, the reflection of shiny green eyes gives away one of the most endangered animals in the world.
"Hey, we got a black-footed ferret," Livieri said.
Livieri, the executive director of a non-profit group called Prairie Wildlife Research, captures the animal, then checks its overall health, gives it a vaccination and notes it in the annual population count before releasing it back into the wild.
Prairie Wildlife Research is a non-profit group which monitors black-footed ferrets that have been released from captivity back into the wild inside recovery sites located in several Western states, including South Dakota and Colorado.
Not long ago, finding a black-footed ferret in the wild was unthinkable. Biologists thought the animal had gone completely extinct. Wanted posters offered $10,000 for a live one.
Then, in 1981, everything changed.
"A rancher's dog found one, killed it, brought it to its owner and they said, 'Oh, my gosh, they're not extinct,'" said Dr. Della Garelle, a biologist and director of conservation at the Cheyenne Mountain Zoo near Colorado Springs.
The discovery kicked off a rare second chance to bring a species back from the brink. The captive breeding program started with only 18 animals.
At Cheyenne Mountain, Garelle and Jeff Baughman are ferret matchmakers. They breed black-footed ferret "kits," or babies, in hopes of one day trading a cage for the wild open prairie.
The process begins with pairing up males and females for three days of rough ferret sex.
"Sometimes we just see motion. The box is rockin' and we don't go knockin'," Garelle said, laughing.
If everything goes right, exactly 42 days later, the kits are born.
"They are born tiny, little, helpless. They weigh only five grams. That's about five pennies," Garelle said.
Then, it's Baughman's job to turn these adorable kits into trained killers. Nearly all of a ferret's diet is prairie dog. So at about 20 days old, with eyes not even open yet, the kits get their first taste of meat.
"Once they get that taste, they are just gangbusters for meat," Garelle said. "They are strict carnivores."
In just a few weeks their new diet transforms the kits from Zhu-Zhu Pet cuteness into loud-mouthed, chattering adolescents.
"This is a bite glove," Baughman, showing off a thick, well-chewed leather glove. "Usually you don't put your fingers in the tips so if they do bite it, they're getting the glove and not your finger."
Black-footed ferrets have had an uphill climb since near-extinction. Each one alive today is the offspring of only 18 wild ferrets. That tiny genetic pool and the inevitable inbreeding has ruined their immune systems.
"They are very prone to plague, distemper, flu, pretty much any disease that walks by, they may die from," Garelle said.
The ferrets' fate is also closely tied to their natural enemy, prairie dogs. Farming, poisoning and even plague have nearly wiped them out. Many ranchers consider prairie dogs pests.
"They eat grass, cattle eat grass, and therefore it's an economic threat," Garelle said.
And as prairie dogs go, so go ferrets.
"They cannot survive without prairie dogs. Once we exterminated all those prairie dogs, that's what caused the near extinction of black-footed ferrets," Garelle said.
Then at three months old, it's moving day.
"They're going to pre-conditioning. It's very exciting," Baughman said, loading ferrets into a van.