Ocean surface warming: impact on toxic benthic dinoflagellates causing ciguatera

Abstract

Ciguatera reef fish poisoning is a debilitating human illness in tropical and some subtropical regions. Toxic precursors produced by tropical benthic dinoflagellates are bio-converted to often more potent toxins and bioaccumulate via the food web in highly sought after table fish. Rising sea surface temperatures are predicted to induce phase shifts on coral reefs. These changes offer increased substrate availability for benthic, toxic dinoflagellates such as Gambierdiscus, Ostreopsis, Prorocentrum and Coolia spp. resulting in range expansions of the causative agents of ciguatera. Ocean currents critically shape the chemical and physical ocean – and coastal environments. Climate change affects wind patterns, which strengthens the East Australian Current forcing warm tropical waters further south. This in turn allows range expansions of ciguatera-associated dinoflagellates and presumably toxin vectors into nonendemic coastal regions changing the ciguatera-risk profile for humans and regional and commercial fisheries in affected coastal areas.