"It needed to be something that would catch some interest and hopefully put the word out there that experimental seabed mining is not ok."
And he was right, already he has raised $3695 through his Givealittle page and all proceeds will go towards KASM's appeal.
Dr Steward said he had lots of pleasure fishing and diving out there and it was one of the best fisheries around New Zealand.
"The TTA have called it a desert but we've dinned out on that one. The reef is full of life, plenty of crayfish but also rare soft sponges and masses of marine life."
Walking the first 200km with his eldest son, Lloyd, Dr Steward is now tackling the final 100km with his youngest son, Jonathan.
On Friday they will walk Patea to Waipipi then on Saturday they will continue to Waiinu Beach.
Gathering as many walkers as they can from Ototoko Beach, Dr Steward plans to end the walk at Castlecliff Beach around 3pm on Sunday.
To donate to Athol Steward's Givealittle fund visit: www.givealittle.co.nz/cause/walkthewalkfor ourocean