As part of their settlement legislation, Ngāti Apa ki te Rā Tō can apply for consent to take tuna from Nelson Lakes National Park for customary use, subject to certain conditions. In 2021, Ngāti Apa ki te Rā Tō received Tiaki Wai Funding from Te Wai Māori for a pilot study to investigate the sustainability of cultural harvesting by combining Māori approaches and scientific methods.

At the heart of this mahi was the sharing of mātauranga Māori and facilitating the intergenerational transfer of cultural knowledge. Population counts, length-weight measurements, and aging of the tuna using the otoliths extracted from harvested individuals provided further insight into the structure of the population.