Preferences of invasive lionfish and native grouper between congeneric prey fishes

Abstract

To gain insight about how an invasive predator may influence native prey, we performed a series of experiments in aquaria to characterize and compare the prey preferences of the invasive red lionfish Pterois volitans and an ecologically similar native mesopredator, the graysby grouper Cephalopholis cruentata. Preference for native congeneric fishes, the fairy basslet Gramma loreto and blackcap basslet G. melacara, were tested. We observed behavior of predators in response to 2 individual prey consisting of cross-factored combinations of species (fairy and blackcap basslets) and size (small and large). Upon initial exposure to prey, lionfish first hunted fairy basslet and graysby first hunted blackcap basslet, with both predators initially preferring large over small fish. Overall behavior (quantified from the entire duration of observation) indicated both predators lacked a preference between basslet species based on total number of strikes and hunting time. Despite essentially identical size ranges of predators studied, graysby overall preferred large basslet across all graysby sizes, whereas the overall preference of lionfish between prey size varied with lionfish size. Importantly, the initial preferences of predators were likely least affected by the unnatural setting in aquaria. By preferentially consuming the lesspreferred prey species of native graysby or by increasing predation on larger basslets, invasive lionfish may enhance coexistence between basslet species or among basslet sizes within local populations structured according to a size hierarchy. Alternatively, increased consumption of basslets may deplete local basslet populations, especially if lionfish exhibit prey switching behavior.

The lionfish Pterois sp. invasion: Has the worst‐case scenario come to pass?

“…Over‐consumed prey species tend to have specific characteristics: small, shallow‐bodied, solitary fishes that live on or just above reefs, that do not remove ectoparasites and that are nocturnally active are at greatest risk of lionfish predation (Green & Côté, ). Although our general understanding of prey selection by lionfish is now deeper, some distinct prey preferences remain puzzling, such as the propensity to attack fairy basslet Gramma loreto Poey 1868 when the ecologically and morphologically similar congener blackcap basslet Gramma melacara Böhlke & Randall 1963 is also available (Kindinger & Anderson, ), which suggests that additional prey characteristics enhance vulnerability to lionfish predation.…”

Integrating remote sensing and diver observations to predict the distribution of invasive lionfish on Bahamian coral reefs

“…Study reefs were chosen based on 2 criteria to encompass (1) the natural range of reefs on the shelf using knowledge of the area gained from previous studies (Pusack et al 2014, Ingeman 2016, Kindinger & Anderson 2016, and (2) a naturally occurring range of lionfish densities. From 2013 through 2016, 8 to 12 reefs were surveyed annually, with some reefs surveyed in multiple years, for a total of 23 unique reefs.…”