Donate a shark tracker: $500
You can name and follow the movements of your adult Port Jackson shark, and we will e-mail you a picture of your shark.

Donations up to $500
We will e-mail you a thank you note with a picture of a baby PJ shark.

How do Port Jackson sharks know where to go?

Port Jackson sharks are a cute, small shark species endemic to Australia. They are very abundant off coastal reefs in eastern Australia during winter, but suddenly disappear for the rest of the year. To figure out where Port Jackson sharks spend their time outside of breeding season, our lab is investigating their home territories, migratory patterns and navigation abilities.

What is the context of this research?

Port Jackson sharks were thought to have a narrow spatial distribution, mostly because they are a small species (~1m long) and are very often seen resting in the ocean floor. However, our research in Jervis Bay, on the east coast of Australia, has shown that Port Jackson sharks migrate very long distances by the end of each winter, only to return the following winter. Our “gold medal” shark swam more than 1000 km south of Jervis Bay in less than three weeks! But if we really want to know the migratory behaviour of this species, we have to track sharks from other locations, for example Sydney Harbour and Port Stephens, and see if they follow the same migratory routes.


What is the significance of this project?

Sharks are vital components of marine ecosystems. They are top predators, which means they help maintain the balance and the health of the ocean. Sharks are currently a big target of commercial and recreational fisheries, or indirectly caught as bycatch, which makes them very vulnerable to extinction because they take a long time to grow and reproduce. Since the 1970s, many shark populations have decreased by over 90% due to overfishing.

A key aspect to help proper management of shark populations is knowing where sharks spend most of their time, how they navigate between these important areas and how human activities might affect them.

By tracking Port Jackson sharks in Australia, we can start to observe their seasonal patterns of movements, and discover if males and females, or juveniles and adults, show any differences in their movements. We can then try to understand why they go to specific places, or why they show such annual patterns. Ultimately, this knowledge will be expanded to other bottom-living species, and most shark species in general.

What are the goals of the project?

The simple

Track the movements of Port Jackson sharks living in Sydney Harbour and Port Stephens.

The details

With each shark adoption we get, we will be able to buy an acoustic tag (Vemco V13-x). We will implant this tag in the shark, and be able to track its movements over the next five to ten years.
Specific questions we plan to answer are:

  • 1. Do sharks from Sydney Harbour and Port Stephens also migrate south?
  • 2. Do males and females differ in their breeding site departure and arrival times?
In the future, we also plan to investigate if Port Jackson sharks have a ‘mental map’ of their territory, and know their way around. We will be testing this by displacing sharks from their home reefs and see if and how they come back home.

Donate a shark tracker: $500
You can name and follow the movements of your adult Port Jackson shark, and we will e-mail you a picture of your shark.

Donations up to $500
We will e-mail you a thank you note with a picture of a baby PJ shark.