The Non-Native Royal Damsel (Neopomacentrus cyanomos) in the Southern Gulf of Mexico: An Invasion Risk?

A diminutive, non-native damselfish ( Neopomacentrus cyanomos ) was recently discovered inhabiting coral reefs near Veracruz, Mexico—far removed from where it is native in the Red Sea and the Indo-Pacific. The quantities found in the Gulf of Mexico (GOM) suggest that the fish has already established a self-sustaining population in this new ecosystem. There is understandable concern, therefore, that this new arrival may become invasive and spread, yet the invasion risk imposed by this fish has not been assessed. In this study, a computer model was employed to deliver a forecast of the potential range of incursion of N. cyanomos in the GOM spanning 5 years. The model incorporated oceanic water flow in the region, tolerances of this damselfish to the ocean environment, and their reproductive strategy in order to supply a temporal and spatial forecast of their spread. From this study, targeted early detection and removal of the fish can be directed if the fish is deemed a threat to native fauna. On the basis of this work, it is foreseeable that the reefs presently harboring N. cyanomos will likely see increased abundance of this damsel. Immediate attempts to eliminate the fish, therefore, should be focused in nearshore shallow waters spanning Veracruz to Frontera, Mexico. Further, water flows in the southern GOM are not widely conducive to long-distance transport of marine organisms with pelagic larvae, reducing the risk of this damsel permeating the greater GOM over 5 years. Aside from N. cyanomos , this study implicitly adds to mounting evidence supporting a biogeographic disconnect between the Veracruz reef complex and the greater GOM and the Caribbean.