The bodies of a 35-year-old man and his five-year-old daughter have been retrieved in waters off Cape Carnot after the pair were swept off rocks on Sunday afternoon.
The Chinese nationals from Adelaide's Holden Hill were part of a group visiting Port Lincoln for the Easter long weekend before the tragedy struck about 1:30pm near Whalers Way on Sunday.
Eyre and Western Local Service Area Superintendent Paul Bahr said other visitors in the area at the time said wave conditions were quite calm and the rocks were relatively dry before the wave hit.
He said a third person was swept into the water but managed to scramble back up the rocks to safety.
"It is unclear as to what they were doing, but it seems a popular place for visitors to stand," he said.
"It's understood other members of the group have gone to jump in to rescue them, but other visitors stopped them and subsequently stopped the number of fatalities growing."
Superintendent Bahr said police had struggled to get the full details of the events that unfolded due to a language barrier and therefore an interpreter had been brought in.
After the alert was raised on Sunday emergency services rushed to the area and commenced a search for the pair.
The police helicopter arrived from Adelaide about 3.30pm and spotted the two bodies from the air.
The five-year-old's body was recovered shortly after but rescuers were forced to call off the retrieval for the man as they ran out of light. They returned on Monday to recover the man's body.
Whaler's Way Sanctuary co-owner Glenn Theakstone said there are signs throughout the sanctuary and on the permit warning visitors of the risks, including plaques commemorating the previous deaths at Cape Carnot.
He said he and his two brothers would contemplate whether to shut the area to visitors or whether to install a universal visual sign warning of dangerous waves.
"We got the call from police that there had been a drowning and a shiver instantly runs down your spine," he said.
"Looking at the sea state...I can not believe anyone tried to go into the caves.
"I spoke to the ranger on the gate and he said he was warning everyone all day if they went around to that side to be careful."
The area has been open to visitors for the last 50 years and Mr Theakstone said there had now been six drownings in the same vicinity, but before Sunday the last was about 30 years ago.
"Everyone brought up on the West Coast knows the sea here can be unforgiving, but that (knowledge) is not common in other areas it seems," he said.
"We don't wish to close Whaler's...about 5-10 million people have gone through the gate over the last 50 years.
"It's an unfortunate event, but it's not an everyday occurrence...you don't expect it at any time."
Mr Theakstone said a review of signage, fencing and safety was conducted every few years.
Police will prepare a report for the Coroner.