Predation rates of Indo-Pacific lionfish on Bahamian coral reefs

Indo-Pacific lionfish, mainly Pterois volitans, are currently invading coral reefs throughout the Caribbean region, where they have the potential to outcompete and prey upon a wide range of native reef animals. Here, we derive the first estimates of rates of predation by lionfish from field observations on natural reefs around New Providence, Bahamas. Although lionfish are reported to be crepuscular in their native range, they were very active during daylight hours. Lionfish were observed hunting at least 19 reef fish species, in at least 9 families. They hunted significantly more on overcast days and at greater depths, and frequently hunted near aggregations of fish at cleaning stations. Lionfish consumed native fish at an average rate of 1.44 kills h-1 (0.29 kills h-1 on clear days and 2.29 kills h-1 on overcast days). This estimate may be conservative if lionfish hunt also between dusk and dawn. This rate is considerably higher than the only known prey consumption rate for P. volitans, which is extrapolated from ad libitum feeding of fish from the native range. Our results imply that using published predation rates from the native range to predict the impacts of lionfish on native Caribbean fish could lead to severe underestimation of these impacts.