I hyperventilate as I hit the water. I'm one of those swimmers who likes to see the bottom and I can't see it here. These fish are big and powerful and there are lots of them. They seem to find me especially attractive, particularly as my cheery guide has been tossing sardines at me to "enhance" my experience. They come towards me at a speed faster than an accelerating Porsche, veering away at the last second before they hit me.
It's amazing, though, how quickly you become accustomed to being surrounded by these creatures and soon I forget my fears and summon enough courage to hand-feed them. It pays to watch your fingers, though - these fish have seriously sharp teeth.
Port Lincoln is a 30-minute flight from Adelaide on the southern tip of the Eyre Peninsula. Although long established as an agricultural port it is now also home to a thriving fishing industry and the town's restaurants offer superb seafood. It's known as the seafood frontier.
I've come to the peninsula to explore outback Australia. The glory of the South Australian outback is that it is so accessible.
I'm heading to a camp in the foothills of the ancient Gawler Ranges, about a two-and-a-half-hour drive from Port Lincoln on a Gawler Ranges Wilderness Safari.
On the way, we stop at Baird Bay. I've heard there's an ex-pat Kiwi there who'll take me swimming with sea lions.
Alan Payne is a former sheep shearer from Ohingaiti near Taihape who has lived at Baird Bay for more than 20 years. In that time he's struck up a special relationship with the resident sea lion colony.
Next thing we are heading out on Alan's boat at low tide to the exposed rocks where the sea lions sun themselves.
Today the sea lions are showing no sign of wanting to swim - until Alan gets into the water. And then an extraordinary thing happens. They rush to join him and soon he's like the pied piper leading them around the bay, frolicking with them, for all the world as if he's a sea lion himself.
I slip over the side of the boat. These Australian sea lions are so different from our more intimidating fur seals. They come to check me out, their big dark eyes just centimetres from my nose. And then the magic happens. They dance for me. Swirling effortlessly and gracefully in a circle, nose to tail, a perfect water ballet. I'm entranced. We play together for ages. They brush against me, welcoming me into their world.
It is, without a doubt, one of the most wonderful experiences of my life.
The sun is low in the sky and I'm keen to get to my outback camp before dark. I've wanted to visit the Outback since I read A Town Like Alice, as a child. And now here I am, driving along the romantic, interminable red dirt roads that I read about all those years ago.
I'm amazed by how green it is out here. I'd been expecting a barren, desert-like landscape but there's plenty of undergrowth.
I reach Kangaluna camp on sunset. My tent is unlike any other I've stayed in. It boasts a master bedroom with queen bed draped with a mosquito net. There's another room with two single beds and then, joy of joys, a bathroom with hot and cold running water and a flushing loo. I am a happy camper!
My hosts, Geoff and Irene Scholz and I dine in a shed open on three sides and made of corrugated iron and recycled wooden beams.
Geoff and Irene whip up the dinner, chatting over the kitchen bench while they produce a feast of fresh local produce, simple and delicious.
Geoff grew up here. He lives and breathes this place and is enthralled by its ancient geology. The Gawler Ranges are well over one and a half billion years old. The Gawler Craton covers nearly 500,000sq km of central South Australia and is the result of one of the largest volcanic eruptions.
On day two of our safari, Geoff takes me to the spectacular Lake Gairdner, a 50,000sq km sea of salt. It's blazing white and hot as a blast furnace to walk on.
Geoff is an affable companion, a true man of the Outback with his dusty Akubra pushed back on his head.
He is one of the characters who have made this part of Australia a very special place to visit.
Top Five on the Eyre Peninsula
1. The brave-hearted will enjoy a swim with the tuna tour from Port Lincoln. You can also hand-feed the fish.
2. Baird Bay Ocean Eco Experience offers the chance to swim with sea lions in a shallow cove
3. The Head of Bight is a great place to view southern right whales as they arrive in great numbers for the winter breeding season. Watch the whales play with their calves.
4. Drive across the Nullarbor, from Ceduna in South Australia to Kalgoorlie in Western Australia. Stop to play a round of golf on the world's longest golf course, Nullarbor Links.
5. If you visit in January, visit the Eyre Peninsula farmers and fishermen's market at twilight on Coffin Bay's foreshore for wine, jams, relishes, pickles and small goods plus fresh seafood.
Two-night itinerary
The Eyre Peninsula is often the highlight of an extended stay in South Australia. Port Lincoln is the peninsula's gateway and just a 40-minute flight from Adelaide.
Day 1: Starting in Port Lincoln, spend your day swimming with bluefin tuna, sea lions or dolphins. Or have a close encounter with a great white shark from the safety of a dive cage. For something more sedate, self-drive the Seafood Trail or choose a Southern Blue Touring's guided tour around the region. Overnight at Port Lincoln.
Day 2: Drive to Coffin Bay National Park, stopping at Mikkira Station to see koalas in the wild. Scenery ranges from granite, limestone and sandstone cliffs to beaches and sand dunes. Coffin Bay National Park features windswept beaches and calmer, sheltered waters off Yangie and Coffin Bay. Spot kangaroos, emus and goannas on walking trails. Overnight at Port Lincoln.
IF YOU GO
Getting there: Fly with Air New Zealand.
Further information: See Explore - Nature and Wildlife and Gawler Range Safaris.
Judy Bailey travelled to South Australia with Tourism Australia, the South Australia Tourism Commission and Air New Zealand.
