Peter was tagged and followed by satellite after he was cleaned up following the oil slick in June 2000.

Scientists lost him after tracking his 800km (500-mile) swim home to Robben Island, home to about 40% of the world's African penguin population.

But pleased scientists say a penguin spotted on a rock is definitely him, after they checked his metal armband.

"Peter has been very clever at keeping undercover. They thought they would never see him again," said a spokeswoman for Earthwatch, the charity which tracked him.

After the terrible oil spill off Cape Town, rescuers took the birds off their island and took them to new homes while they were cleaned up.

Peter and two other mates were kitted out with the sophisticated transmitters after they were rescued so that scientists could watch what they did.

Plucky Peter was apparently the first of the birds to actually make it home, but no one saw him.