Snow leopards live in the remote mountains of countries such as Bhutan, China, India, Mongolia and Nepal. They are endangered—a mere 4,000 to 6,000 individuals are spread out over Central Asia—and live solitary lives, usually active just at dawn and dusk. Coupled with their exceptional camouflage, this makes them notoriously elusive—although they figure largely in the mythology of many Asian cultures, wild snow leopards weren’t even caught on camera until the 1970s.

Now, for the first time, a team of researchers from the Snow Leopard Trust and Panthera, a wild cat conservation organization, have captured video of a wild snow leopard mother and cubs in a den, seen above. “This is incredible. Snow leopards are so rare and elusive that people often talk about them as ‘ghosts’ of the mountains,” said Brad Rutherford, Executive Director of the Snow Leopard Trust. “This is the first documented visit of a den site with cubs, and thanks to this video we can share it with the world.”

The search began back in 2008, when an team of scientists affixed GPS collars to several snow leopards encountered in Mongolia’s Gobi Desert. Then, this past May, a pair of females from the study began restricting their movements to a smaller area, indicating they were preparing to give birth. Researchers tracked the VHF signals emitted by the collars through steep mountain outcroppings, coming upon a pair of dens located less than four miles apart in the Tost Mountains on June 21st.

“As we stood outside the den we could hear the cub and smell the cats but not see anything inside the den,” said Panthera scientist Orjan Johansson. He and colleagues acted quickly, taping a camera to their antenna pole and extending it over the ledge blocking the den entrance. The footage captured shows a female leopard looking up at the camera, keeping a protective paw over her cub.

At the second den—a narrow crack in a cliff wall—the scientists discovered that the mother was away hunting, leaving her two male cubs unattended, seen below. “This was an unprecedented opportunity,” said Rutherford. “We wanted to be as careful as possible and only take the most pressing data.” The team quickly weighed, measured, photographed and collected hair samples from the cubs, which allowed genetic testing that confirmed sex and other information. More pictures of the cubs are available at Panthera’s photo gallery.

The team also implanted microchip ID tags—each of which are roughly the size of a grain of rice—under the cubs’ skin, which will allow the researchers to identify the animals as part of future conservation projects. After leaving, they tracked signals from the mother’s VHF collar to ensure that she returned to the den, and they note that she is still with the cubs now. The researchers do not plan to visit the dens again, so as to limit future disturbance to the cubs.

The team says that the information collected will be extremely valuable in future attempts to conserve the endangered species. Remarkably little is known about snow leopard behavior, and most of what we understand about the rearing of cubs is known from studying the animals in a zoo environment. Until know, scientists had to speculate about typical litter sizes, cub weights, sex ratios and survival rates.

“Knowledge about the first days and weeks of life is vital to our understanding of how big cat populations work, and how likely it is for a newborn to reach adulthood and contribute to a healthy population,” said Panthera’s Howard Quigley. “A valid conservation program requires such information, which this new development in snow leopard research provides.”

The organization plans to use the microchip ID tags affixed to the cubs to learn about the characteristics of a typical snow leopard upbringing, such as how long the cubs remain in dens, when they being to hunt with their mothers and when they start to venture out on their own. Along with future GPS collaring programs, these data will assist with large-scale conservation efforts across the species’ range.

“We have spent years trying to determine when and where snow leopards give birth, the size of their litters and the chances a cub has of surviving into adulthood,” said Tom McCarthy, director of Panthera’s snow leopard program. “This is one of those exceptional moments in conservation where after years of effort, we get a rare glimpse into the life of an animal that needs our help in surviving in today’s world.”