A harvest method informed by traditional knowledge maximises yield and regeneration post harvest for karengo (Bangiaceae)

摘要

Within New Zealand, a group of bladed intertidal algae in the Bangiaceae family known as karengo is harvested entirely from wild stocks and is culturally important for MAori (New Zealand's indigenous people) both as a food and historically for trade. To sustainably maintain this wild resource, it is important to optimise harvest strategies. Knowledge gained from intergenerational harvest of karengo by MAori communities could provide a sustainable harvest technique. Harvesting trials between July 2013 and August 2013 assessed the effect of a traditional harvest method informed by mAtauranga MAori (traditional knowledge), pulling by hand, on the regeneration of karengo. Traditional pulling was compared with cutting and scraping harvest methods. A sustainable harvest technique was determined by assessing yield and post harvest regeneration within the winter growth period from each harvest method. Hand pulling resulted in the greatest biomass regeneration post harvest, providing a 46 % greater yield than scraping and no discernable difference in biomass 6 weeks post harvest compared to unharvested plots. A later harvest (August) resulted in an 83 % greater yield than an early harvest (July). Therefore, to obtain an optimal yield whilst maintaining a sustainable harvest, hand pulling late in the season is recommended. These findings support and strengthen a harvest technique based on mAtauranga MAori and provide information to empower kaitiaki (MAori guardians) to actively manage and preserve highly valued wild karengo stocks.