Abstract
Over the past three decades, lionfish (Pterois volitans and P. miles) from the Indo-Pacific have invaded the northwest Atlantic Ocean, Caribbean Sea and the Gulf of Mexico. As generalist predators with a broad diet, they could pose a major threat to economically and ecologically important species and, therefore, the overall health of coral reef ecosystems and the communities that rely on them. In Bermuda, the lionfish invasion appears to be progressing at a slower rate than elsewhere in the invaded range, providing an opportunity to study their ecological impact at an early stage. This study used stable isotope analysis of lionfish, their major prey, and their competitors to investigate the feeding ecology of lionfish in Bermuda and provide a more complete evaluation of their potential impacts on community structure and trophic interactions. Results suggest that lionfish in Bermuda primarily derive resources from the plankton-based food web, with only a small contribution from food chains supported by macroalgae. Further, it appears that lionfish resource use overlaps substantially with other similarly-sized sympatric mesopredators, in particular the coney grouper (Cephalopholis fulva), a species commonly targeted by local commercial fisheries. This visualization of Bermuda’s demersal ecosystem in two-dimensional isotope space, the first of its kind, will help track the ecological impact of lionfish over time, predict potential changes in community structure, and better inform developing control strategies for this invasive species.
Highlights
Since lionfish (Pterois volitans and Pterois miles) were first documented in the western Atlantic Ocean in 1985 (Whitfield et al, 2002), growing evidence suggests that they could have a substantial ecological impact across their invaded range (Albins and Hixon, 2008; Lesser and Slattery, 2011; Green et al, 2012)
Among demersal piscivores of similar size, lionfish are a top predator in Bermuda and occupy a trophic position of 3.4
The wide δ-space occupied by lionfish highlights a broad isotopic niche characteristic of a generalist predator feeding from a varied resource base, in agreement with stomach contents analyses (Peake et al, 2018) and similar work using stable isotope analysis (SIA) (Muñoz et al, 2011; Layman and Allgeier, 2012; O’Farrell et al, 2014)
Summary
Since lionfish (Pterois volitans and Pterois miles) were first documented in the western Atlantic Ocean in 1985 (Whitfield et al, 2002), growing evidence suggests that they could have a substantial ecological impact across their invaded range (Albins and Hixon, 2008; Lesser and Slattery, 2011; Green et al, 2012). Despite being the first location outside of United States waters where non-indigenous lionfish were reported, overall lionfish densities in Bermuda are typically lower than those in other locations within the invaded range (Eddy, 2016), suggesting that the invasion is progressing more slowly there than elsewhere This provides an important opportunity to investigate the ecological characteristics of lionfish (e.g., trophic position and niche) at an early stage of the invasion, before a population “explosion” occurs and potential impacts on community structure arise. Recognizing that SIA provides an opportunity to evaluate the degree to which their diverse prey contributes to the isotopic values of lionfish, this study measured the δ15N and δ13C values for lionfish, a suite of other consumers (including potential lionfish competitors and known prey species), and primary producers, to determine the trophic structure of the invasive lionfish population and the community of coral reef fishes along Bermuda’s coastline as a means to illustrate overall community structure and explore potential impacts
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
