Feeding Strategies and Biological Traits of the Lessepsian Migrant Pterois miles (Bennett, 1828) in the Messenian Gulf, SW Greece

The common lionfish, Pterois miles (Bennett, 1828), is one of the most recent Lessepsian migrants into Mediterranean Sea. In this study, a first attempt is made to explore some life history parameters of the species in the Messenian Gulf (SW Greece). Its growth, morphometry, and feeding behavior were studied in samples collected with a speargun during the summer and autumn of 2021 at depths from 0 m to 20 m. Lionfish were found to have established a thriving population, growing faster and reaching larger sizes than in their native range. Analysis of their diet showed that this species is a generalized feeder with a preference towards piscivory, targeting key species for local food webs, such as the damselfish (C. chromis), possibly provoking competition with other native predators. Overall, the dietary habits of the species, rapid growth rate, and lack of predation pressure make the lionfish an additional risk for the integrity of the Messenian marine ecosystem, an ecosystem which is already disturbed by intense human intervention.