Shark attack on dolphin shuts down Sydney’s northern beaches

“The deceased dolphin has since been transported to the Australian Wildlife Registry at Taronga Wildlife Hospital for an autopsy [animal autopsy]’ said the spokeswoman.

The vice president of the organization for whale rescue and research in Australia, Jools Farrell, said rescuers hoped the autopsy would reveal the cause of death: “At this point we are not confident that the death was caused by the sharks.”

Footage shows the injured dolphin trying to swim before lifeguards and swimmers dragged him onto the beach.

Macquarie University wildlife scientist Vanessa Pirotta said dolphins are known to be preyed upon by sharks — particularly if they have previously suffered injuries or are in compromised health.

“Today’s footage of the dolphin shows it had wounds that were not fresh, suggesting the animal was likely in poor health prior to today’s interaction and was a vulnerable target for other animals,” she said. “There was clear evidence of tooth marks on the animal’s tail, which looked like white flesh that may have aged.”

Pirotta said the incident was a natural process, but removing the dolphin reduced the likelihood of more sharks appearing in the area.

“It’s all part of a natural ecosystem where if one animal is doing poorly and is an easy target, other animals in the ocean are likely to benefit,” she said. “But a decomposing or sick animal can attract sharks.”

Dorsal Watch website, which lists shark sightings around the world, reported that Surf Life Saving NSW sighted three 2.5m bull sharks off Shelly Beach just before 9am.