Spatio-temporal variation in the diet composition of red lionfish, Pterois volitans (Actinopterygii: Scorpaeniformes: Scorpaenidae), in the Mexican Caribbean: Insights into the ecological effect of the alien invasion

Abstract

Background. The observed expansion of the red lionfish, Pterois volitans  (Linnaeus, 1758), in the Caribbean represents one of the most rapid marine fish invasions in the history. The invasion rate of this top predator has resulted in a marked negative effect on local fish populations in the Caribbean by impacting local biodiversity. The main aim of this work was to conduct the morphological identification of prey items from the lionfish diet, and to determine the spatio--temporal variation of the lionfish diet composition in different sites of the Mexican Caribbean, to have a better knowledge of how this invasive species is impacting local species of commercial or ecological importance in the region. Materials and methods. The Mexican Caribbean study area was divided in three zones; North (one locality Isla Contoy), Central (three locations Xpu-Ha, Akumal and X’Cacel), and South (two locations Banco Chinchorro and Xcalak). The fish were collected, from different habitats, using SCUBA diving and Hawaiian harpoon. Collected fish were taxonomically identified, measured for total length (TL) and standard length (SL), and weighed to the nearest gram. Prey items were identified using a dissection microscope. After identification, prey items were separated, counted, and weighted individually. Finally, statistical analyses were made for all the samples using this study database, containing predators and prey items. Results. A total of 76 prey species were identified in 962 lionfish stomachs; 47 of them represented fishes and 29—crustaceans. Fishes of families Pomacentridae, Labridae, and Scaridae were the most abundant diet components of lionfish. Rhynchocinetidae, Penaeidae, and Solenoceridae were the most representative Crustaceans families among the prey items. Molluscs were present as diet components only as incidental food. Conclusion. Red lionfish, known for its high competitive capacity, preyed more intensively on fishes than on crustaceans. Therefore, it is evident that the lionfish presence in the Mexican Caribbean may affect mainly the local population of reef fishes. The presently reported results contribute to a better understanding of the red lionfish invasion in the Caribbean.

Keywords

• invasive species
• diet component
• reef fishes
• mar