|Giant Australian Cuttlefish. Photo by Professor Sean Connell|
Scientists are calling on the public to help with new research seeking greater understanding of the biology of the Giant Australian Cuttlefish to help stop its decline.
Led by the University of Adelaide, the researchers will study the movement - at several stages of its life history - and the population structure of the Giant Cuttlefish in the northern Spencer Gulf.
They also aim to resolve whether the northern Spencer Gulf cuttlefish is a separate species, and develop a model to measure and assess the effects of potential environmental and human impacts on the cuttlefish population.
Chief Investigator Professor Bronwyn Gillanders says: "The Giant Australian Cuttlefish is renowned for its extraordinary breeding habits when each winter thousands of cuttlefish gather in a colourful display near Point Lowly to mate and lay their eggs on a small stretch of rocky reef. This is the largest known breeding aggregation of any cuttlefish species in the world."
"Historically there were tens of thousands of individuals but there have been dramatic declines since the 2010 breeding season."
"As part of this new project, we are asking fishers, divers, boaters and others to report any sightings of cuttlefish and their eggs, especially in the northern Spencer Gulf. Sightings will help determine if the cuttlefish are moving elsewhere to breed and how the distribution and abundance of the population might be changing."
The research is supported by Australian Government funding through the Fisheries Research and Development Corporation. The University's partners include the South Australian Research and Development Institute (SARDI), Primary Industries and Regions SA (PIRSA), Department of Environment, Water and Natural Resources (DEWNR), and South Australian Museum.
Professor Gillanders says the magnitude of the decline in cuttlefish numbers at Point Lowly has raised concerns about the cuttlefish and highlighted the lack of knowledge about its population structure and dispersal within the northern Spencer Gulf. Most studies have concentrated on the adults focusing around Point Lowly.
"The dispersal of hatchlings away from the spawning site and location of sub-adults is currently unknown," she says. "Our earlier research has also suggested this northern Spencer Gulf population may be genetically isolated from populations in the rest of the State, and may constitute a separate species.
"If so, there is an even greater imperative to identify the factors behind the decline and to see if any particular stages of the cuttlefish are more vulnerable than others."
Members of the public are asked to record sightings of individuals (numbers and size) and eggs at www.redmap.org.au