Investigating the association between pelagic fish and dimethylsulfoniopropionate in a natural coral reef system

Abstract

Dimethylsulfoniopropionate (DMSP) is a biogenic chemical produced by marine algae that is associated with areas of high primary and secondary productivity in the ocean. In laboratory experiments, DMSP has been shown to be an effective feeding attractant for a variety of fresh and saltwater fishes, suggesting that it might also function as a foraging cue in the natural environment. Here we explore whether free-roaming pelagic fishes associate with periodic elevations of DMSP in their natural foraging habitat. Working in the vicinity of the coral reefs of the Flower Garden Banks in the Gulf of Mexico, we found that daily changes in the number of pelagic jack fishes (Carangidae) were significantly correlated with natural changes in concentrations of DMSP in the water column. These results provide the first evidence of a correlation between variation in the number of pelagic fishes and a specific habitat-associated chemical cue in the ocean.