A tiny but highly significant satellite tag was due to pop up to the sea's surface somewhere off the South African coastline early on Tuesday in a move that has shark scientists buzzing with anticipation.

This is one of two pop-up satellite tags and an ultrasonic tag that were fitted to what could be the world's best-known fish: Maxine, the ragged-tooth shark released off Arniston in March.

Maxine - initially named Max, as she was thought to have been a "he" - was released after spending nine years as a prime attraction at the Two Oceans Aquarium at Cape Town's Waterfront.

She was caught as a three-year-old in shark nets off the KwaZulu-Natal coast in 1995, when she was badly hurt.

Maxine was tagged and released by the Natal Sharks Board, then travelled 1 400km down the coast before being caught again 91 days later, this time by an angler during a fishing competition near Struisbaai on the southern Cape coast.

Aware that the aquarium was looking for sharks, the competition organisers put her in the back of a bakkie and took her to a tidal pool 20km away.

There, her life was saved by a man called Mackie - hence Max and later Maxine - who spent an hour walking her up and down the pool before she recovered enough to survive.

At the aquarium, it was a full three months before she started feeding, the school of yellowtail in her tank finally proving too hard to resist.

After nine years, Maxine was fitted with the tags and released in March as part of a research programme called SOS Foundation M-Sea Programme - run jointly by the aquarium and the AfriOceans Conservation Alliance.

Lesley Rochat of Fish Hoek, an environmental filmmaker and founding member of the alliance, said the first of the pop-up satellite tags had been programmed to be released from Maxine and well, pop up to the surface at 6am on Tuesday.

However, there would be a delay until the first of a network of Argos satellites passed overhead. The satellites would pick up the signal and transmit it to Argos headquarters in Toulouse, France.

They in turn would relay the information to Malcolm Smale of the Port Elizabeth Museum who would decode it to establish Maxine's exact position and pass it on the team in Cape Town.

"This will all happen within 12 hours or so, so we should know by this evening and we will then head out either on Tuesday evening or early on Wednesday morning," Rochat said on Tuesday. "But just where that position will be, your guess is as good as mine."

Maxine's release and her fishy version of a "long swim to freedom" has been well publicised, and a documentary screened on the 50/50 environmental programme on Sunday had resulted in a new flood of interest, Rochat said.