Life Below Water – Cabbage Tree Bay Aquatic Reserve

Giant Cuttlefish

Interview with Sian Liddy, Marine Ecologist. Sian describes why Cabbage Tree Bay is important for Giant Cuttlefish.  The video contains overlay shots of Giant Cuttlefish and Sian observing their behaviour underwater in the bay

Video text transcript

(Sian is sitting on the rocks overlooking Cabbage Tree Bay.  She describes why Cabbage Tree Bay is important for Giant Cuttlefish.  The video contains overlay shots of Giant Cuttlefish and Sian observing their behaviour underwater in the bay.)

Sian Liddy: The Giant Cuttlefish is the largest species of cuttlefish in the world and we are lucky enough to have them right here in Cabbage Tree Bay.  Giant Cuttlefish are really amazing animals.  They actually have three hearts and bluish green blood and as the cuttlefish are hunting or even when they’re looking for a mates, they can change the colour and the texture of their skin in an instant and this is really impressive because they are actually completely colour blind.  Their eyes can pick up polarised light and they can camouflage to their surroundings even in complete darkness. 

Males can puff themselves up in order to make them seem more attractive or more aggressive.  So, if a cuttlefish feels threatened, he can release ink from an ink sac to confuse or disorientate any potential predators.  Females have been known to mate up to 17 times a day with two to eight different males and the males will use modified arms to transfer a sperm packet to the female and then the female will actually use this to fertilise the eggs one by one and attach them to rocky surfaces with a gelatinous covering.

After these exhaustive mating events, they typically die.  They only live for about two or three years.  Following that, you can find these cuttle bones washed up along the beach.  They have this internal shell.  You can see they have this aragonite lattice made up of calcium carbonate.  It has a lot of bubbles that the cuttlefish can fill with air or liquid and it helps it control its buoyancy in the water column.

The diverse temperate reef here at Cabbage Tree Bay is a great habitat for these beautiful, intelligent creatures.