Browsing by Author "Ospina Alvarez, Andres"

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    Integration of biophysical connectivity in the spatial optimization of coastal ecosystem services
    (ELSEVIER, 2020) Ospina Alvarez, Andres; de Juan, Silvia; Davis, Katrina J.; Gonzalez, Catherine; Fernandez, Miriam; Navarrete, Sergio A.
    Ecological connectivity in coastal oceanic waters is mediated by dispersion of the early life stages of marine organisms and conditions the structure of biological communities and the provision of ecosystem services. Integrated management strategies aimed at ensuring long-term service provision to society do not currently consider the importance of dispersal and larval connectivity. A spatial optimization model is introduced to maximise the potential provision of ecosystem services in coastal areas by accounting for the role of dispersal and larval connectivity. The approach combines a validated coastal circulation model that reproduces realistic patterns of larval transport along the coast, which ultimately conditions the biological connectivity and productivity of an area, with additional spatial layers describing potential ecosystem services. The spatial optimization exercise was tested along the coast of Central Chile, a highly productive area dominated by the Humboldt Current. Results show it is unnecessary to relocate existing management areas, as increasing no-take areas by 10% could maximise ecosystem service provision, while improving the spatial representativeness of protected areas and minimizing social conflicts. The location of protected areas was underrepresented in some sections of the study domain. principally due to the restriction of the model to rocky subtidal habitats. Future model developments should encompass the diversity of coastal ecosystems and human activities to inform integrative spatial management. Nevertheless, the spatial optimization model is innovative not only for its integrated ecosystem perspective, but also because it demonstrates that it is possible to incorporate time-varying biophysical connectivity within the optimization problem, thereby linking the dynamics of exploited populations produced by the spatial management regime. (C) 2020 Elsevier B.V. All rights reserved.
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    Reproductive resilience: a paradigm shift in understanding spawner-recruit systems in exploited marine fish
    (WILEY, 2017) Lowerre Barbieri, Susan; DeCelles, Greg; Pepin, Pierre; Catalan, Ignacio A.; Muhling, Barbara; Erisman, Brad; Cadrin, Steven X.; Alos, Josep; Ospina Alvarez, Andres; Stachura, Megan M.; Tringali, Michael D.; Burnsed, Sarah Walters; Paris, Claire B.
    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.