Giant Cephalopods Gather In Huge Numbers
The giant Australian cuttlefish have returned to their South Australian breeding ground in higher numbers than have been seen in decades this year. As many as 250,000 are thought to have gathered along an 8km stretch of rocky reef in Spencer Gulf in recent months.
The giant Australian cuttlefish (Sepia apama) is the world's largest cuttlefish. Populations have been in decline since the 1990s.
The cuttlefish have a life span of just 12-18 months and breed during the months of May to August.
Males, which can reach 50cm long and weigh 10kg, employ a fascinating mix of camouflage to match rocks or seaweed, sparring and changing colour to win female attention in a colourful dance.
The females lay between 100 and 300 eggs that hatch babies the size of a thumbnail, and then these baby cuttlefish move along the sea bottom and into the Upper Spencer Gulf.
Local dive and snorkelling tour leader Tony Bramley said his snorkelling tours and scuba diving trips have been booked out over the past weeks because of the increased numbers.
'Compared to even the last two seasons that have been very good, this has been exceptional,' Bramley said.
Scientists are still crunching this year’s numbers but Bramley estimates some 250,000 of the cephalopod have arrived in their Point Lowly winter breeding ground.
The booming numbers are despite the South Australian government allowing fishing of the cuttlefish outside the restriction zone around Port Lowly for the first time since the grounds were protected in 2013. Conservationists fear this may have a negative effect in future years.