The traditional history of Manihiki and Rakahanga tells us that the human discoverer was Huku.
He had sailed into these waters from Rarotonga on a fishing expedition.
When he came to a part of the ocean referred to as “te tukuanga i Whaka-hotu” he noticed an upgrowth of rock or land (tapua whenua) projecting from the sea bottom but not high enough to rise up above the surface of the ocean.
On seeing the coral upgrowth, Huku then recited a “pehe”, or traditional chant, after which he then returned to Rarotonga with the idea that the upgrowth would eventually reach the surface and become land.
To read more go to : Ethnology of Manihiki and Rakahanga