A suspected Antarctic minke whale has been rescued three times from the Port Lincoln foreshore after swimming into shallow water during low tide.

Andrew Veimulen was the second person to rescue the whale from the town jetty.

He said he spotted the whale in trouble not long after it had been rescued the first time.

"It was beached just under the jetty there and having a bit of trouble getting out," Mr Veimulen said.

"Then it disappeared for a while and we just walked up and down the jetty about 15 minutes later, and lo and behold it came back.

"We thought, 'it looks like it's beached itself again'."

Mr Veimulen said a crowd that included school children started "piling around" so he decided to go "down there and give it a bit of a push".

Sorry, this video has expired Minke whale sent back to sea. Video by Brett Cooper, Tumby Bay.

He took off his shoes and socks and slowly approached the whale in the water.

"It didn't seem all that fussed by me, so I just came up and gave it a bit of a gentle nudge with my hands and gave it a little bit of a talking to, I suppose, and said 'Hey little mate, do you want to go back into the ocean?' and then it kind of did," Mr Veimulen said.

"All I really did was give it a bit of a nudge in the right direction and away he — or she — went."

Department for Environment Water and Natural Resources (DEWNR) senior compliance officer David Wilkins said his office was notified of a whale beaching, twice at the town jetty and later down near the wharf.

"Another member of the public actually found it down near the corner of the wharf and the silos ... and they [also] turned its head around and pointed it back out towards the ocean," he said.

Whale identified to most likely be Antarctic minke

Mr Wilkins said the whale was of a species not often seen locally.

"[Doctor] Cath Kemper from the [SA] Museum has to a degree of confidence identified it as being an Antarctic minke, which is quite rare up here," he said.

He said that while the rescuers had done the right thing, if people saw a whale or another marine creature in distress the first thing they should do is to call the Eyre Peninsula ranger on duty on 8688 3223, which will divert to a mobile phone 24 hours a day, seven days a week.

"It's one of those extreme circumstances where we would say, 'thank you very much for helping', but if other members of the public come across a situation like this, they need to stick to the rules because it can cause more stress to the animal," Mr Veimulen said.

He said that while whales could look helpless while stranded, they were actually quite strong and people could get injured.

"These aren't small creatures at times and they can actually give a good whack with their tail," he said.