"We know that paua do not fare well in freshwater and heavy rainfall and easterly sea conditions could have caused large amounts of freshwater from the Clutha River to be pushed into the coastal waters around Kaka Point.
"Until the cause of the wash-up is confirmed, we advise people not to gather or eat any of the washed up paua."
University of Otago marine science lecturer Dr Gaya Gnanalingam agreed.
"Paua can handle some fluctuations in salinity, but this large input of freshwater and sediment might have been too much for them to handle. Strong easterly swells that accompanied the rain would have also played a part," she said.
"We've seen this at Port Molyneux in 2013 near the first set of reefs south of the Clutha, and we've measured low salinities all the way to Campbell's reef in the past during flood events."
National Aquarium of New Zealand general curator Joe Woolcott said if the paua were still alive and in good shape they might be able to reattach if they made it back to suitable habitat, but too much damage or time out of the water would make recovery unlikely.
Local man Glen MacPherson said although the massive amount of dead paua was "devastating", he was cautiously hopeful for paua in the area.
"I went diving six months after the big paua wash-up in 2013 and I was surprised to see how many were still there."
