Taro swamps on Ontong Java Atoll: past, present, and future

Ontong Java atoll, Solomon Islands, transitioned in 1900 from a colonial copra export economy to one dominated since 1973 by bêche-de-mer sales. Prior to colonial influence, its inhabitants relied on two staple root crops – taro (Colocasia esculenta) and giant swamp taro (Cyrtosperma merkusii) – alongside coconuts and fish. This article examines taro cultivation on wetland ‘taro swamps’ across six of the atoll’s 120 islands. We assess the decline of taro cultivation triggered by imports of carbohydrate foods, hurricane damage in 1967, introduced pests and diseases, and ongoing salinization from storm surges and climate change. Integrating swamp area and productivity data with approximated dietary carbohydrate needs, we estimate the carrying capacity of the atoll was between 2450 people (taro at 25 per cent dietary energy) and 6195 people (taro at 10 per cent). The higher estimate aligns with H. I. Hogbin’s (1930) estimate of 5000–5500 for the pre-contact population. Our findings highlight the cultural and subsistence importance of taro cultivation in atoll communities before colonial contact.