"I always said if I ever get my stuff together I want to come and dive. Finally, after many years I've decided I want to do it."
This was partly due to the wake-up call of a stroke he experienced in November, he said.
"Also I was told the sharks were good this year, so that's what swayed it. I've always wanted to do it."
The attack in 1971 occurred after he skipped his school swimming sports to go surfing, he said.
"It was 10.30 in the morning and I was meant to be at Moana Pool, but I thought 'I don't want to do that'."
He then ventured into the swell with three friends.
"I was paddling out through the rip, next thing I was under the water, I couldn't get to the surface. I honestly thought I'd been run over by a boat."
Watkins then saw a shark to his side releasing its jaws from his leg and board.
"Blood started pouring out of my leg, I started panicking."
The shark attacked three more times, the last of which was the most "spectacular", he said.
"He was making these grunting noises. He took one bite of the board and snapped it in half like a potato chip."
Both he and the board were flung into the water.
Watkins managed to "belly board" his way to safety on half a board. His leg required 90 stitches and the scar remains to this day.
He has surfed since, but never in Dunedin. Watkins tried to go shark diving in South Australia a few years ago, but it was cancelled due to bad whether.
If his booking was confirmed for next month, his wife Rose would watch from the sideline.
"Sharks aren't a problem, [she doesn't like] the cold water."
