The Fin Review: The hunter becomes the hunted

A Peel-Harvey Estuary dolphin's dorsal fin is almost entirely bitten off, typical of a shark wound. Photo: MDRP.
A Peel-Harvey Estuary dolphin's dorsal fin is almost entirely bitten off, typical of a shark wound. Photo: MDRP.

One of the questions I am most often asked is, “If you see dolphins, are you safe to enter the water without worrying about sharks?” 

In short, dolphins, who are top predators themselves, are indeed on the menu for larger sharks. 

Although our research team is yet to observe a shark, we have observed evidence of their presence through the shark bite scars and wounds on the Mandurah dolphins. 

In the pristine Shark Bay ecosystem, approximately 74 per cent of all individual dolphins have shark bite scars.

This shows the violent interactions of dolphins and sharks, but also the dolphin’s remarkable ability to escape from a predator’s attack. 

Often, we see bite scars on the dorsal surface of the dolphin.

When under attack, dolphins are thought to spin around in order to get bitten on the back as opposed to the vulnerable ventral surface. 

The underside of the dolphin is where their organs sit, and must be protected.

As part of our research, we monitor the presence of wounds and scarring caused by sharks.

These unique scars and marks also help us to identify one dolphin from another.

So far, the dolphins inhabiting the coastal areas and the Dawesville cut have the most evidence of shark predation events.

We all may have fears about sharks, but it is important to keep in mind that the presence of this apex predator is an indication of a healthy ecosystem.

The Mandurah Dolphin Research Project is a partnership between Murdoch University, City of Mandurah and Mandurah Cruises that commenced in January 2016.

They are measuring how many dolphins use the Peel-Harvey waterways and how they are connected to dolphins in nearby coastal waters.

You can follow the MDRP on Facebook or through this fortnightly column.

Comments

Discuss "The Fin Review: The hunter becomes the hunted"

Please note: All comments made or shown here are bound by the Online Discussion Terms & Conditions.