A critically endangered rhino calf has been born in a sanctuary in Indonesia, giving renewed hope to those attempting to save the species from extinction. There are believed to be just 100 Sumatran rhinos left in the world, the majority of which live on the island of Sumatra in Indonesia.

Ratu, a wild rhino living in the Sumatran Rhino Sanctuary in Way Kambas National Park, gave birth after approximately 16 months of pregnancy. It was Ratu's second successful birth: her first calf, Andatu, was born at the sanctuary in 2012 and marked the first time a Sumatran rhino had been born in a sanctuary for more than 140 years.

The new female calf and Ratu, whose name means "Queen", are in good health and the newborn started feeding within two hours, sanctuary spokesman Novrizal Tahar said.

Last year the Sumatran rhino was declared extinct in Malaysia. As the smallest of the five remaining rhino species, they are the only Asian rhinoceroses with two horns, which makes them a valuable target for poachers. "This kind of rhinoceros is only found in Indonesia now," Tahar explained. "So we need to have a strong commitment, not only in Indonesia but around the world, to protecting and making sure these species stay alive", he said.

The natural rainforest habitat of the Sumatran rhino has been decimated due to palm oil, pulp and paper plantations. In March, environmentalists made contact with a Sumatran rhino on the Indonesian part of Borneo island for the first time in 40 years, but it died a month later.

The new arrival is the fifth Sumatran rhino to be born in captivity, and has been welcomed by scientists across the world who hope to the species in captivity.