Virus threatens bottlenose dolphins
Bottlenose dolphins are dying in their hundreds off the East Coast of the US in what is believed to be an outbreak of a virus. South African dolphins have so far been spared.
It is thought the 333 dolphins that have washed up near New York are infected with the morbili virus, which is similar to the canine distemper virus.
US scientists believe the outbreak could continue until next year.
Dr Stephanie Plon, a marine biologist at the Nelson Mandela Metropolitan University, said "antibodies to the virus were found in South African dolphins stranded in Eastern Cape 10 years ago. So we know it has been at our shores, but there has never been an outbreak."
She added: "There is no reason it can't happen in the South African population. The dolphins are social animals. When they come together, the morbili virus spreads .
"Diseases spread as animals swim further afield and as climate conditions change."
Plon, veterinarian Morne de Wet and National Zoological Gardens wildlife pathologist Dr Emily Lane have been studying South African dolphins killed in shark nets off the Durban coastline.
Shark net deaths present an unusual opportunity to study "ordinary" surviving bottlenose and humpback dolphins . As dolphins are at the top of the food chain, they are a good indicator of the state of the ocean.
"If we weren't doing the study, the 20 dolphins that die in nets each year would be put on the rubbish heap. We're not condoning shark nets but we are using the unfortunate deaths to try to learn more about dolphins' health," Plon said.
De Wet said: "The study suggests the dolphinsare fine as there is no pressing disease that kills them."
But the scientists found an abnormal number of parasites in the shark net dolphins.
"The parasites seem to be a problem but we'll continue to do research to verify if it is," said Plon.