Our common dolphins are a remarkable success story

Did you know that the waters near Mornington are home to some common dolphins that are global celebrities? The Dolphin Research Institute's unexpected encounter with a small group of these remarkable dolphins in 2005 sparked a journey of discovery. Two decades later, the institute’s Port Phillip Common Dolphin Project continues to unveil new insights every year.

You see, everywhere else in the world except Port Phillip, common dolphins live in the open ocean – and there are many hundreds in Bass Strait. Between 2005 and 2007, the institute’s researchers identified only eight individuals. Today, the Port Phillip Common Dolphin Catalogue has more than 150 known dolphins. Most of the individuals first seen in 2005 are still regularly sighted today.

Keeping track of these fascinating dolphins is no simple task. Subtle marks on dorsal fin images taken during boat surveys are used like ‘fin prints’ to identify individual dolphins. Thousands of hours of detective work revealed that many of the original females had reared more than one calf. Many of these youngsters thrived and now have their own calves, making the third generation. Some of the original dolphins we know as V-Nick, Esther and Jean are now grandmas.

At least six third-generation calves were confirmed in 2023. This is a remarkable success story for our dolphins and the bay itself, especially given the disastrous trends for coastal dolphin communities in Australia and globally.

In 2023, the institute’s researchers also confirmed the movement of common dolphins from near Mornington out to the Bass Strait waters near Wonthaggi.

These discoveries are part of the Port Phillip Common Dolphin Project, a long-term initiative to understand Port Phillip's unique dolphin community. This project is crucial for wildlife and ecosystem reporting and management, ensuring the continued protection of these remarkable animals.

The Dolphin Research Institute is a Peninsula forpurpose organisation working to achieve positive outcomes for dolphins and whales, their environment and the community for 33 years. The Port Phillip Common Dolphin Project, Two Bays Whale Project, and ‘i sea, i care’ ambassador program are proudly supported by donors and council partners (for ‘i sea, i care’).

You can help protect these remarkable dolphins by joining the Adopt-A-Dolphin program, reporting sightings, and committing to dolphin distancing –like Neighbourhood Watch for dolphins – at www. dolphinresearch.org.au

ELLA HUTCHINSON, Williamson Research Fellow at The Dolphin Research Institute