He said highlights of his career were working with overseas navies and diving around Indonesia and the Pacific with some of the most famous divers in the world.
Now at age 77, he doesn't have plans to stop diving, and is heading to West Papua and French Polynesia in 2019, and Indonesia and the Solomon Islands in 2020.
"And of course also I'll be diving in New Zealand."
Despite his achievements, which include introducing two pieces of diving safety equipment which are now used for everyday safety while diving, he remains humble.
"I must say I have been privileged and had the chance to do all sorts of things with all sorts of interesting people in different parts of the world.
"I left Napier Boys High School on a Friday and left New Zealand by sea on the Monday to go to London to study when I was 18."
As an optometrist, he worked in Napier, but also ran a visiting practice to Wairoa.
He described his conservation work as "quiet", done through writing submissions and talking to ministers, but felt it was important in New Zealand today.
"You look at the rivers, you look at the sea, you look at the fish populations, it's all pretty terrible."