Can the Life History Trait Divergence of Two Extremes of a Cold-Water Genus Distribution Offer Evidence for Their Vulnerability to Sea Warming?

Cold- and deep-water species such as Molva show low resilience to anthropogenic pressures, they become particularly vulnerable at the warm edges of their distribution. In this study, poorly documented Mediterranean ling (Molva macrophthalma) population from northwestern Sea was analysed. This area is considered a cul-de-sac in sea-warming hotspot, where M. macrophthalma shows health status experiencing climate-related reduction abundance. Several life-history traits (length maturity, reproductive cycle, fecundity style, oocyte recruitment pattern, breeding strategy) are here described for first time evaluate performance (oocyte diameter production) relation fish condition (the HSI relative index). Additionally, results compared with those similar species, blue dypterygia), inhabiting cool edge its distribution, hypothesised have higher status. Our indicate that capital breeder restricted secondary growth group-synchronous development. terms, stressed southern exhibited worse condition, lower investment reproduction, smaller size larger but fewer primary oocytes, size-standardized production oocytes than northern dypterygia. Significant differences were also found. These findings reinforce environment’s role shaping potential Altogether, study suggests high sensitivity pressures both and, especially ling, it importance introducing monitoring conservation measures ensure sustainability populations.