This photo received from the Borneo Species Programme of the WWF-Malaysia, shows a night shot of a Borneo rhino in eastern Sabah state. The rare image of the rhino believed to be pregnant was captured in Malaysia's wilderness.

A rare Borneo rhino, thought to be pregnant, has been caught on camera in Malaysia, and wildlife experts said Wednesday a new calf would be a lifeline for the near-extinct species.

Just 30 rhinos remain in the wild in , which is shared by Malaysia, Indonesia and Brunei, and researchers are only able to monitor the population through images captured on remote camera traps.

Images of the rhino, "believed to be a pregnant female, estimated to be below 20 years" were captured by a camera trap in February, the Malaysian arm of World Wide Fund for Nature (WWF) - said in a statement.

"There are so few left in the world that each calf represents a lifeline for the species," international rhino expert Terry Roth said.

The Borneo sub-species is the rarest of all rhinos, distinguished from other Sumatran by its relatively small size, small teeth and distinctively shaped head.

The Sumatran rhinoceros is one of the world's most endangered species, with few left on Indonesia's Sumatra island, the north of Borneo island and peninsular Malaysia.

Laurentius Ambu, wildlife director for Malaysia's Sabah state, where the female rhino was spotted, said two rhino calves had also been seen in a similar area and urged the government to do more to enforce laws against poaching.

"Habitat protection and enforcement have been recognised as the main strategies in ensuring the survival of the rhino population in forest reserves," he said.

The WWF said the rhino's future on Borneo island would depend on preserving sufficient forest reserves for the animal.

Raymond Alfred, head of the WWF's Borneo Species programme said data from an ongoing rhino monitoring survey programme showed the animal's home range was affected by the expansion of palm oil plantations.

Malaysia is the world's second-largest exporter of palm oil after Indonesia, and the two countries account for 85 percent of global production.