South Australian scientists are ecstatic to find that the Great Australian Cuttlefish has returned to the Spencer Gulf for breeding this year. Their numbers have been down over the last few years and scientists don’t know why, or where they went.
The Great Australian Cuttlefish can weigh up to 13kg. Image: Howard Womersley.
The cuttlefish, with it’s blue blood pumped through three hearts, and the ability to change colour at the drop of a shell, makes the cuttlefish an enigmatic creature to say the least.
The increase in the breeding aggregation numbers this year is also a source of interest to scientists.
“We’ve looked at a whole range of biotic and abotic factors that could have contributed to it, but nothing jumps out.” says Professor Bronwyn Gillanders.
Gillanders says she is quite excited to that there were a lot sighted early in the season, but that the proof will be when surveys are completed to estimate the abundances on this years breeding aggregation.
Listen to Bronwyn Gillanders speak about the cuttlefish on ABC Rural.
The Australian giant cuttlefish is the largest cuttlefish species in the world reaching a total length of up to 1 m and a weight of 15 kg. Researcher Bronwyn Gillanders at the University of Adelaide’s Environment Institute is heading up research on these cuttlefish as part of the Spencer Gulf Ecosystem & Development Initiative (SGEDI).
Giant Cuttlefish logged on REDMAP, April 2013
During May and June, the Australian Giant Cuttlefish (Sepia apama) will form dense spawning aggregations in around Point Lowly, in the northern Spencer Gulf, South Australia. This is the only know site in the world where the cuttlefish congregate to breed.
Over the last few years however, the numbers of these aggregations are on the decline and scientists aren’t sure why. Are the Giant Cuttlefish choosing to lay their eggs somewhere else?
This is where you can help! If you spot a group of 10 or more Giant Australian Cuttlefish in South Australian waters, you can log it on the REDMAP (Range Extension Database and Mapping Project) website.
Recreational and commercial fishers, SCUBA divers, boaters and scientists are being invited to spot, log and map sightings of Giant Australian Cuttlefish. Researchers are interested in sightings of aggregations of more than 10 adult cuttlefish as well as eggs, when spotted in South Australian waters, especially northern Spencer Gulf.
You can find out more and download the information flyer. We hope to see your sightings pop up over the coming months!