Two incredibly rare (and equal parts adorable) Amur leopard cubs born earlier this year at Connecticut’s Beardsley Zoo are offering their species a chance at survival.

Amur leopards (Panthera pardus orientalis), a subspecies of leopard, are critically endangered with just 80 animals remaining in the wild and 200 housed in captivity around the world. Given their small global population, the zoo says that each leopard cub born is “extremely important” to the survival of the species.

“Amur leopards are on the brink of extinction,” said Zoo Director Gregg Dancho in a Facebook post. "The Species Survival Plan’s breeding recommendation is designed to bolster the number of individuals in human care, for potential future breeding, as well as the opportunity to return certain members of the species back to the wild someday. The birth of these cubs brings a few more precious Amur leopards to the population, which can help ensure the survival of these majestic animals for future generations.”

But the two cubs’ entry into life wasn’t without challenges. Six-year-old leopard Freya gave birth two three cubs on January 25 but only two survived. The third was euthanized following injuries induced by Freya from hyper-grooming behaviors. At the time, zoo veterinarians had to remove the cubs and place them under 24-hour care. The female cub underwent a lifesaving surgery and had her tail removed following her mother’s behavior. She was also treated with antibiotics for an infection and has since completed medication and is doing well.

Zoo officials say the cubs’ six-week survival is a “critical milestone”. They have been hand-feeding the babies five times every day with a feline milk replacement formula supplemented with vitamins helping the duo to put on healthy weight; at last count, they weighed around 2.5 kilograms (5.5 pounds) with the male measuring in slightly larger.

Not only do the cubs offer hope to their species, but the female cub has a unique condition known as melanism where the body produces excesses of black pigments, melanin, (essentially the opposite of albinism). Her extremely rare black color occurs in about 1-in-10 leopards on Earth, most of which occur in Southeast Asia where tropical forests offer an abundance of shade to blend into. Black leopards and black jaguars, the only other big cat documented to experience melanism, are known as panthers.