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Christensen, V., Coll, M., Buszowski, J., Cheung, W. W. L., Frölicher, T., Steenbeek, J., et al. (2015). The global ocean is an ecosystem: simulating marine life and fisheries. Global Ecology and Biogeography, 24(5), 507–517.
Résumé: Aim There has been considerable effort allocated to understanding the impact of climate change on our physical environment, but comparatively little to how life on Earth and ecosystem services will be affected. Therefore, we have developed a spatial–temporal food web model of the global ocean, spanning from primary producers through to top predators and fisheries. Through this, we aim to evaluate how alternative management actions may impact the supply of seafood for future generations. Location Global ocean. Methods We developed a modelling complex to initially predict the combined impact of environmental parameters and fisheries on global seafood production, and initially evaluated the model's performance through hindcasting. The modelling complex has a food web model as core, obtains environmental productivity from a biogeochemical model and assigns global fishing effort spatially. We tuned model parameters based on Markov chain random walk stock reduction analysis, fitting the model to historic catches. We evaluated the goodness-of-fit of the model to data for major functional groups, by spatial management units and globally. Results This model is the most detailed ever constructed of global fisheries, and it was able to replicate broad patterns of historic fisheries catches with best agreement for the total catches and good agreement for species groups, with more variation at the regional level. Main conclusions We have developed a modelling complex that can be used for evaluating the combined impact of fisheries and climate change on upper-trophic level organisms in the global ocean, including invertebrates, fish and other large vertebrates. The model provides an important step that will allow global-scale evaluation of how alternative fisheries management measures can be used for mitigation of climate change.
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Freon, P., Sueiro, J. C., Iriarte, F., Evar, O. F. M., Landa, Y., Mittaine, J. F., et al. (2014). Harvesting for food versus feed : a review of Peruvian fisheries in a global context. Reviews in Fish Biology and Fisheries, 24(1), 381–398.
Résumé: Peru is the top exporter of fishmeal and fish oil (FMFO) worldwide and is responsible for half and a third of global production, respectively. Landings of “anchoveta” (Engraulis ringens) are used nearly exclusively for FMFO production, despite a proactive national food policy aimed at favoring the direct human consumption of this inexpensive species. It may be surprising that in a country where malnutrition and caloric deficit constitute major issues, a low-priced and highly nutritious fish such as anchovy does not have stronger domestic demand as a food fish. Here, we review and assess eight potential politico-socio-economic processes that can explain this situation. The main explanation are dietary habits, the preference for broiler and the higher profit from anchovy sold as feed fish compared to its use as a food fish due to historically high FMFO prices, boosted by an increasing demand for aquaculture in a context of finite forage and trash fish resources. In addition, the recent introduction of an individual quota system has shifted bargaining power from processors to fishers, thereby increasing competition for the raw material. This competition results in an increase in anchovy prices offered by the feed fish industry due to its onshore processing overcapacity, which is detrimental to the food fish industry. In the end, although the dominant use of anchovy for fish feed is largely explained by integrating these market mechanisms and other minor ones, this use raises other issues, such as rent redistribution through public policies, employment, equitability and utility (low social costs), and resource management (threats to ecosystems or global change). Different policy scenarios are proposed in relation to these issues.
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Freon, P., Sueiro, J. C., Iriarte, F., Miro Evar, O. F., Landa, Y., Mittaine, J. - F., et al. (2013). Harvesting for food versus feed: a review of Peruvian fisheries in a global context. Reviews in Fish Biology and Fisheries, .
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Goetze, J. S., Claudet, J., Januchowski-Hartley, F., Langlois, T. J., Wilson, S. K., White, C., et al. (2018). Demonstrating multiple benefits from periodically harvested fisheries closures. J. Appl. Ecol., 55(3), 1102–1113.
Résumé: 1. Periodically harvested closures (PHCs) are one of the most common forms of fisheries management in Melanesia, demonstrating multiple objectives, including sustaining fish stocks and increasing catch efficiency to support small-scale fisheries. No studies have comprehensively assessed their ability to provide short-term fisheries benefits across the entire harvest regime. 2. We present a novel analytical framework to guide a meta-analysis and assist future research in conceptualizing and assessing the potential of PHCs to deliver benefits for multiple fisheries-related objectives. 3. Ten PHCs met our selection criteria and on average, they provided a 48% greater abundance and 92% greater biomass of targeted fishes compared with areas open to fishing prior to being harvested. 4. This translated into tangible harvest benefits, with fishers removing 21% of the abundance and 49% of the biomass within PHCs, resulting in few post-harvest protection benefits. 5. When PHCs are larger, closed for longer periods or well enforced, short-term fisheries benefits are improved. However, an increased availability of fish within PHCs leads to greater removal during harvests. 6. Synthesis and applications. Periodically harvested closures (PHCs) can provide short-term fisheries benefits. Use of the analytical framework presented here will assist in determining long-term fisheries and conservation benefits. We recommend PHCs be closed to fishing for as long as possible, be as large as possible, that compliance be encouraged via community engagement and enforcement, and strict deadlines/goals for harvesting set to prevent overfishing.
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