One of the most magical experiences you can have here while freediving in Melbourne is swimming with wild apex predators. Southern Bluefin Tuna are built for speed and swim effortlessly through the water with barely a tail flick.
They are a pelagic fish which means they are not held to a specific reef or area but instead cover great distances as they swim and look for food. They school together and can be found in incredibly large schools although when they get larger (70kg or more) they tend to swim in smaller schools.
In our summer months here in Melbourne if you have access to a boat that can safely head out the Port Philip Bay heads and out to sea you can be fortunate enough to see schools swimming along the surface. You will want to head out in days with low swell and low wind making it easier to see them swimming just below the surface.
You need to be mindful of your approach as the sound of the motor can send them diving deep and it's best to head ahead of the school and let them swim towards the divers.