Sisters Rashmi and Richa Sharma show the certificates they received for swimming a stretch of the South Atlantic last Thursday. Picture by Anindya Shankar Ray

Calcutta sisters Rashmi and Richa Sharma have swum the choppy North Atlantic, battled the Indian Ocean’s hungry tide and stroked their way through the freezing South Atlantic. The one thing they haven’t been able to conquer yet is their fear of sharks!

Back home after a successful three-week trip to South Africa that added two seas to their tally, all that the duo can talk about is how they had eyes only for the sharks in those picture-perfect locales.

“Last Thursday, we were on a boat to Robben Island to start our eight-km South Atlantic swim and I was constantly scanning the waters for the slightest hint of a shark fin,” recalled 23-year-old Rashmi, the elder of the siblings and the only Indian to cross the English Channel thrice.

“There had been a shark attack a day before we reached Cape Town. The shark bit off both legs of a British tourist on a beach close to the coast of Blouberstrand, to which we were to swim from Robben Island,” added 20-year-old Richa, seated in the living room of the Sharma family’s Kidderpore apartment on Monday.

Beaches around Cape Town like Fish Hoek, Kalk Bay, St James and Muizenberg were closed to the public following the September 28 attack on Briton Michael Cohen, but the Sharma sisters obtained special permission to swim the shark-infested stretch.

The siblings had swum an 11.5-km stretch of the Indian Ocean near Port Elizabeth days earlier and needed to surmount the South Atlantic challenge to complete the treble of conquering a recognised channel or strait in three oceans.

In 2009, the duo had done a lap of the North Atlantic in the Strait of Gibraltar.

Rashmi said the scariest part of the South Atlantic swim was breaking away from her sister on the home stretch.

“It was a very difficult decision for me after Richa developed hypothermia. Her body temperature had dropped so low that she was having trouble thinking clearly, let alone swimming fast. My strength was going down too; so I had to go for the shore, leaving her behind,” she recounted.

The guides on the boat had asked the sisters to stay within a radius of eight metres of one another, beyond which the shark-repellent device wouldn’t work. “It was an unnerving thought that a shark could attack us any moment…. We would yell ‘Shark!’ even if we saw dolphins or seals,” recounted Rashmi with a laugh.

Richa overcame hypothermia to complete the swim from Robben Island, where Nelson Mandela had been imprisoned during his anti-apartheid crusade, to Blouberstrand in two hours and 57 minutes. Her older sister took 12 minutes less to complete the stretch.

Those on the boat had advised Richa to climb aboard several times, but she refused to give up. She required five hours of hospitalisation after completing the swim.

The siblings’ father is a retired Navy officer now employed with a private firm and their mother is a schoolteacher. The duo’s next target is to swim stretches of the Pacific and Arctic oceans.

So would two sisters swimming five oceans be a world record? “I don’t know about the record, but we are definitely up for the challenge,” said Rashmi, who hopes to accomplish the feat by 2013.

The swimming sisters had a surprise guest on Sunday. “Sports minister Madan Mitra met us the very day we returned to Calcutta and promised us a Diwali gift of Rs 1 lakh. He has also promised to discuss with us our future plans,” said Richa, who has won medals for Bengal in boxing in the 57-kg category and zips around town along with her sister in a Scooty.