Cameras set up in large tanks are capturing what impact varying levels of fine limestone sediment in the water has on the feeding habits of squid, as part of a project for the WAMSI Westport Marine Science Program.

The project, which started recently, is led by Dr Ben Saunders, a Senior Lecturer in the School of Molecular and Life Sciences at Curtin University.

It will be used to inform the Westport project in Cockburn Sound.

Dr Saunders said traditionally research had focused on the lethal effects of sediment on marine life during dredging operations.

“What we are interested in is the lowest measurable effects, where the behaviour of the animal starts to change,” Dr Saunders said.

“They may start to feed differently and there could be changes to their body condition and overall health.”

Three levels of sediment are being used to replicate what is likely to be in the water during a dredging operation.

“We are testing 25 milligrams per litre, then 44 milligrams per litre, and a control without added sediment.”

The highest level is based upon the turbidity levels where previous research suggests that 5% of fish species begin to be affected.

“We feed the 17 squid in front of the video cameras and we try to get them to come in so we can record any delay between the fish going into the tank and the squid realising it is there and coming in to eat it.”

One sign the squid may not be able to see their prey is fish remaining uneaten at the base of the tank.

Two trials will be conducted, and each trial runs for 10 days.

The squid are fed and monitored three times a day and researchers regularly test water quality and monitor the video footage.