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A close relationship between adult abundance and stock productivity may not exist for many marine fish stocks, resulting in concern that the management goal of maximum sustainable yield is either inefficient or risky. Although reproductive success is tightly coupled with adult abundance and fecundity in many terrestrial animals, in exploited marine fish where and when fish spawn and consequent dispersal dynamics may have a greater impact. Here, we propose an eco‐evolutionary perspective, reproductive resilience, to understand connectivity and productivity in marine fish. Reproductive resilience is the capacity of a population to maintain the reproductive success needed to result in long‐term population stability despite disturbances. A stock's reproductive resilience is driven by the underlying traits in its spawner‐recruit system, selected for over evolutionary timescales, and the ecological context within which it is operating. Spawner‐recruit systems are species specific, have both density‐dependent and fitness feedback loops and are made up of fixed, behavioural and ecologically variable traits. They operate over multiple temporal, spatial and biological scales, with trait diversity affecting reproductive resilience at both the population and individual (i.e. portfolio) scales. Models of spawner‐recruit systems fall within three categories: (i) two‐dimensional models (i.e. spawner and recruit); (ii) process‐based biophysical dispersal models which integrate physical and environmental processes into understanding recruitment; and (iii) complex spatially explicit integrated life cycle models. We review these models and their underlying assumptions about reproductive success vs. our emerging mechanistic understanding. We conclude with practical guidelines for integrating reproductive resilience into assessments of population connectivity and stock productivity.

The inclusion of behavioural components in the analysis of a community is of key relevance in marine ecology. Diel and seasonal activity rhythms or more longlasting\ud changes in behavioural responses determine shifts in population, which in turn affect measurable abundances. Here, we review the value of cabled videoobservatories as a new and reliable technology for the remote, long-term, and highfrequency monitoring of fishes and their environment in coastal temperate areas. We provide details on the methodological requirements and constraints to appropriately measure fish behaviour at day-night and seasonal temporal scales from fixed videostations.\ud In doing so, we highlight the relevance of an accurate monitoring capacity of the surrounding environmental variability. We present examples of multiparametric video, oceanographic, and meteorological monitoring made with the western Mediterranean platform OBSEA (www.obsea.es; 20 m water depth). Results are reviewed in relation to future developments of cabled observatory science, which will greatly improve its monitoring capability due to: i. the application of Artificial Intelligence to aid in analysis of increasingly large, complex, and highly interrelated biological and environmental data, and ii. the design of future geographic\ud observational networks to allow for reliable spatial analysis of observed populationsPostprint (published version

When gene flow is limited and harvesting is intensive, fishing may alter life histories and favour trait combinations that collectively reduce adult body size. However, empirical evidence of downsizing of adults in small-bodied coastal fish is still scarce, in part due to the lack of knowledge about the selective nature of certain fishing gears, such as recreational angling, and the difficulties in estimating the dispersion of pelagic early-life stages. Using the small-bodied sedentary coastal marine fish Serranus scriba as a model, we first empirically show that recreational angling selects for life-history traits (i.e. increased reproductive investment) that promote downsizing of adults. Second, using Lagrangian particle dispersion modelling, we show how local hydrodynamics generates patterns of limited connectivity and the emergence of meta-population structure. Finally, the life histories presently observed in isolated populations of S. scriba that experienced differential fishing pressure matched expectations of fishing-induced downsizing of adult body size. Body size is an important trait in aquatic food webs, and evolutionary downsizing might have unforeseen consequences. From a precautionary perspective, maintaining the metapopulation structure and the full range of genotypes inherent in them is important, even for smallbodied, geographically restricted fish species that are mainly harvested by recreational anglers.

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