Wi Mahuika signed the East Coast sheet of the Treaty of Waitangi between 5 and 12 May 1840 at Tūranga (now Gisborne). He was a Ngā Pōtiki rangatira (chief) of the Te Aitanga-a-Māhaki iwi (tribe).
Mahuika was involved in land sales in Poverty Bay in 1868, and in the sales of the Te Motu Block in 1874 and the Waikohu-Matawai Block in 1875.
In 1880 Mahuika appeared in the Resident Magistrate’s Court in Tūranga charged with not repaying a debt. Mahuika argued that he would have to sell his land for less than it was worth to pay the debt immediately, and asked for a delay. The court ordered him to make five monthly instalments of £10.
In 1888, the Native Land Court awarded Mahuika was awarded a portion of the Mangatū Block because his descent from Te Waka Mahuika meant he had both ancestral claims and residency. Wi Pere from Wahia, the main owner of the block, agreed to work with Mahuika to mark off its boundaries.