Fishers’ Perceptions of Ciguatoxin Fish Poisoning and Modeling Biomagnification of Ciguatoxin in the Trophic Dynamics of Caribbean Coral Reef Ecosystems

Abstract

Ciguatoxin fish poisoning (CFP) is caused by the consumption of tropical and subtropical fishes and other marine species with high levels of ciguatoxin (CTX) in their tissues. CTX is a polycyclic neurotoxin produced by single-celled, photosynthetic dinoflagellates in the Gambierdiscus and Fukuyoa genera which are found in close association with benthic autotrophs. CTX enters the food web when these dinoflagellates are inadvertently consumed by herbivores grazing on their preferred substrates. The toxin biomagnifies up the food chain to the top predators and if humans consume seafood with high levels of CTX it can cause a variety of harsh symptoms. The best way to avoid CFP is to avoid toxic fishes. However, CTX is undetectable by physical inspection. To help prevent CFP cases, I, along with my colleagues, created two predictive models in Ecopath with Ecosim with data we collected and data from the literature, for areas in Puerto Rico, identified as CTX hotspots and coldspots by fishers. I confirmed the fishers' information by sampling fishes and estimating CTX levels in their tissues using a bioassay. We also collected toxic dinoflagellates and show here that the hotspot had much higher densities of these cells than the coldspot. We recommend managers in Puerto Rico establish a routine monitoring program for the toxic dinoflagellates to be used in conjunction with the models presented here to help predict when certain fishes may be toxic along specific reefs. This would mean a safer, more efficient, and more robust fishing economy in Puerto Rico.