Riranga: Amphidromous Sicyopterus spp. Whitebait on Lavongai Island (Papua New Guinea)

In the Tungag language of Lavongai Island in the Bismarck Archipelago, Papua New Guinea (PNG), the term riranga refers to amphidromous gobies that periodically form large aggregations of ‘whitebait’ in estuaries. This article presents biological and ethnographic data, and collates linguistic data from multiple sources, regarding these periodic aggregations of riranga. It sheds light for the first time in this country on this fish’s importance in local culture. Molecular analysis of riranga shows that the species forming most of the aggregations is Sicyopterus cynocephalus, an amphidromous sicydiine goby, the most common Sicyopterus species found in PNG. The article provides descriptions of the life history that locals recount regarding these animals; of the perceived and observed periodicity of the fish’s arrival; the local explanatory framework for the fish’s behaviour; the fishing and preservation techniques used; and several prohibitions and rules which the fish’s presence entails. Local knowledge is compared to ichthyological data, showing that local descriptions are very precise. Finally, collated comparative linguistic data is presented concerning cognate terms to ‘riranga’ in the Oceanic group of languages to which Tungag belongs. Inferring from this data, the article shows that periodical aggregations of amphidromous fish (including, but not limited to gobies) in estuaries of Oceanic islands are locally culturally salient and are likely to have been so throughout the region since at least the onset of expansion of human settlement beyond the site of initial emergence of Proto-Oceanic, ~3500 years ago, an expansion which has been linked to the ‘Lapita cultural complex’.