Increase Rituals and Environmental Variability on Small Residential Islands of Torres Strait

A rich ethnography on increase (zogo) rituals and shrines is available for Torres Strait Islanders of tropical northeast Australia. Most zogo shrines are associated with increasing garden produce and associated nourishing rains. Furthermore, zogo shrines tend to be associated with small (mostly <1 km²) residential islands of the Central and Eastern Islands which experience the lowest rainfall in the region and periodic droughts. To help offset dry season environmental stresses and associated food shortages, the Central Islanders imported garden produce from the Eastern Islanders. Increase ritual shrines expressed inter-island social relationships with Central Islander zogo shrines, often incorporating stones imported from the Eastern Islands and many Eastern Islander zogo shrines featuring stones and shells imported from the Central Islands. In this sense, the exotic stone and shell materiality of zogo shrines was an explicit metaphorical expression of the embeddedness of increase rituals within broader social processes of exchange relationships and subsistence risk buffering strategies. As ethnographic patterns reveal that relative use of the increase rituals correlated with regional horticultural and rainfall variability, it is hypothesized that long-term trends in use of increase rituals intensified with environmental stress, especially extended periods of drought.