Every winter thousands of Giant Cuttlefish (Sepia apama Gray) aggregate to spawn along a restricted area of rocky reef in northern Spencer Gulf, South Australia. It is the only known spawning aggregation of cuttlefish in the world and represents an exceptional cuttlefish mating system of high complexity. Females move around the area paying little heed to males, and males pursue females and compete for them. S. apama male tactics are diverse. Females attach their eggs individually to the underside of rocks, ledges, and caves in subtidal rocky reef habitats, and the eggs hatch in 3–5 months.

References

Hall, K. C. and R. T. Hanlon. 2002. Principal features of the mating system of a large spawning aggregation of the giant Australian cuttlefish Sepia apama (Mollusca : Cephalopoda). Mar Biol 140: 533-545

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