The moment an animal sanctuary worker serenaded a rhino calf to sleep with his guitar has been captured on camera.

The Care for Wild Rhino Sanctuary in Sonpark, South Africa, welcomed a new calf into its care in June after it was rejected by its mother.

She seems to have formed a particular bond with one carer, who is seen here serenading the young rhino to sleep with his guitar.

According to the sanctuary, the rhino "is doing well and continues to improve as each day goes by."

"On behalf of Petronel Nieuwoudt and the team at Care for Wild, thank you to everyone for all of your well wishes regarding the new calf at our rhino orphanage in South Africa. She is doing well and continues to improve as each day goes by!"

At the beginning of the 20th century, there were half a million rhinos across Africa and Asia, but now there are around 29,000, although population numbers are slowly increasing again.

Poaching for rhino horns is the greatest threat facing the creatures. Another major threat is habitat loss from human population growth and the clearance of land for human settlement and farming, as well as agricultural production like logging.