Ecological characteristics of the invasive pufferfish Lagocephalus sceleratus (Gmelin, 1789) in Rhodes, Eastern Mediterranean Sea. A case study

In this study, the ecological and social impact of the invasive pufferfish Lagocephalus sceleratus on the coastal habitats of an area in the eastern Mediterranean Sea (Rhodes Island) was investigated. Seasonal quantitative sampling in two common coastal habitats were used to investigate habitat use by different life-stages. Sandy areas were found to be highly important for the early life stages of L. sceleratus. In contrast, Posidonia oceanica habitats were mainly preferred by larger (>29 cm) reproductive adults, not exceeding 64 cm. Lagocephalus sceleratus was found to feed on invertebrates and fish, while size classification revealed a tendency for a diet shift with increased size. During the early life stages, L. sceleratus inhabits sandy bottoms where it feeds on various invertebrates. The predominant molluscan species found in the diet of larger (>20 cm) L. sceleratus individuals were the economically important Sepia officinalis and Octopus vulgaris. The size at which 50% of individuals have reached maturity was estimated at 36 cm. With increased size, habitat shift to seagrass meadows most possibly occurs to meet both the increased demand in prey availability and requirement for appropriate spawning ground. The condition factor for L. sceleratus showed significantly higher values during summer than all other seasons and this was attributed to the spawning season and increased feeding. Social impacts were alarming due to increased public attention concerning its lethal effects (presence of tetrodotoxin), if consumed. Its high abundance in coastal fish communities of the studied area combined with ecological and social impacts, clearly classify L. sceleratus as a pest for fisheries and a potential threat for biodiversity.