The Vulnerable European spiny lobster Palinurus elephas (Fabricius, 1787): A body-size based and fishery study from NW Aegean Sea, Greece

Abstract

The European spiny lobster, Palinurus elephas (spiny lobster or P.elephas thereafter), a highly valued species in the NW Aegean Sea, Greece, faces significant fishery pressure and population decline. This study provides novel insights into its biology, population dynamics, and fishery status in Thermaikos Gulf and the National Marine Park of Alonissos and Northern Sporades (NMPANS). Using data from 308 individuals collected in 2018–2019, we assessed morphometric relationships, age composition, growth, mortality, and exploitation rates. Carapace length-weight relationships showed negative allometry, with no significant sex differences. Eight age classes were identified, with a dominant fourth-year cohort (43.35%). Von Bertalanffy growth models estimated an asymptotic length of 234.09 mm and longevity of 24.6 years. The exploitation rate (0.85) exceeds sustainable limits (EMSY = 0.55), indicating overfishing, with fishing mortality (0.85) surpassing FMSY (0.17). Larger individuals were found in NMPANS, suggesting some protective effect, but the population remains at risk of collapse. Greek fish auction data revealed potential illegal landings, highlighting enforcement challenges. We recommend reduced landings, enhanced gear selectivity, and systematic monitoring to ensure sustainability. These findings underscore the need for ecosystem-based management to conserve P. elephas and associated threatened species.