Bioinvasions are defined as the establishment of a species in an area where it has not existed previously. Usually the result of an anthropogenic introduction, bioinvasions pose a great threat to coral reef ecosystems. One example of an anthropogenically-induced bioinvasion is that of the lionfish (Pterois spp.) to the Atlantic basin. First reported in Bonaire, N.A. in 2009, the Indo-Pacific lionfish has spread rapidly, with 177 fish reported as of 31 March, 2010. One of the purposes of this study was to document interspecific interactions of lionfish with prey and non-prey fish species at twilight, when lionfish are reported to be active. Interactions were video recorded for further analysis. Additionally, stomach contents of lionfish on Bonaire were analyzed and compared to lionfish from a similar study in the Bahamas, which determined that as lionfish size increases, so does the % volume of fish in their diet. Lionfish, collected by the Bonaire National Marine Park and volunteers, were categorized according to total length for use in this study. Prey items found in the stomach contents were identified to the lowest possible taxon. It was hypothesized that as the size classes of lionfish increased, an increase in the % volume of fish and a decrease in the % volume of shrimp in their diet would be observed. Lionfish were observed interacting more with potential prey items than non-prey items based on video analysis. Data analysis of stomach content found that as lionfish size increased, the amount of fish by % volume increased from 60% volume in the smallest size class to 93% volume in the largest size class. This study showed that as lionfish size increases, they rely more heavily on fish as a part of their overall diet, and the fish they are consuming are those they are observed interacting with most.
This student research was retrieved from Physis: Journal of Marine Science VII (Spring 2010)19: 27-33 from CIEE Bonaire.