The wrecks at Tangalooma are a treasure chest of marine wildlife within a short snorkel from the beach.
To snorkel the wrecks, look at the direction the current is going and pick the opposite end to start from, swim up to that end an then just drift through the wrecks looking at the fish as corals along the way.
It's a hot spot for Maori Rass/parrot fish, garfish, black fins, snapper and most other Northern Queensland reef species.
The best wildlife is in the middle of the wrecks where you can swim into the missing chunk in the rusted out ship which is full of coral and fishies.
If you're not brave enough to swim out to the wrecks yourself you can book a guided snorkelling tour with the tangalooma resort people for $39pp. They'll provide you all the gear and take you to and from the reef so you can spend more quality time at the wrecks.