Variability in Carcinus maenas Fecundity Along Lagoons and Estuaries of the Portuguese Coast

Abstract Although Carcinus maenas as a species is widely studied, research focusing on fecundity still scarce. The main objective of this study was to evaluate size-fecundity relationships across different lagoons and estuaries, along the Portuguese coast, understand how local environment affects reproductive patterns. Between 2019 2020, ovigerous females were collected from Southern (Ria Formosa Ria de Alvor), Central (Rio Sado) Northern regions Aveiro) Portugal, each female estimated by counting weighing eggs. Morphometric (carapace width–egg counting; egg counting–egg weight; body wet weight–egg carapace width–body weight) inferred 180 egg-bearing with width between 26.96 61.25 mm. A positive correlation morphological parameters observed. Differences in found among all systems, northern southern varying 22121 408538 eggs per female. Furthermore, regional gradient observed regions, lower temperature estuaries displaying an increase fecundity. Rio Sado also affected salinity. Fecundity differences associated hydrodynamics, temperature, salinity systems. No statistically significant Carapace Width—Body Wet Weight regressions performed studied system, indicating that, contrary fecundity, somatic growth C. not latitudinal or environmental conditions.