JAKARTA, Indonesia — A Sumatran rhinoceros has given birth at an Indonesian sanctuary in a success for efforts to save the critically endangered species.

The International Rhino Foundation said the female calf was born on Thursday, weighs about 45 pounds (20 kilograms) and looks healthy and active.

“We haven’t stopped smiling since the moment we were sure she was alive and healthy,” said IRF’s executive director Susie Ellis in a statement. “While one birth does not save the species, it’s one more Sumatran rhino on Earth.”

Only an estimated 100 Sumatran rhinos remain, mostly on the island of Sumatra, and several are in captivity. They are threatened by destruction of tropical forest habitat and poachers who kill the animals for their horns, which are prized for making ornaments and for use in traditional medicine in China and other parts of Asia.

The species was rediscovered in the Indonesian part of Borneo through trails and footprints in 2013.

But one member of the small population on Borneo died in April after a wound from a poacher’s trap became infected.