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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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GASCUEL, D., COLL, M., FOX, C., GUENETTE, S., GUITTON, J., KENNY, A., et al. (2016). Fishing impact and environmental status in European seas: a diagnosis from stock assessments and ecosystem indicators. Fish And Fisheries, 17(1), 31–55.
Résumé: Stock-based and ecosystem-based indicators are used to provide a new diagnosis of the fishing impact and environmental status of European seas. In the seven European marine ecosystems covering the Baltic and the North-east Atlantic, (i) trends in landings since 1950 were examined; (ii) syntheses of the status and trends in fish stocks were consolidated at the ecosystem level; and (iii) trends in ecosystem indicators based on landings and surveys were analysed. We show that yields began to decrease everywhere (except in the Baltic) from the mid-1970s, as a result of the over-exploitation of some major stocks. Fishermen adapted by increasing fishing effort and exploiting a wider part of the ecosystems. This was insufficient to compensate for the decrease in abundance of many stocks, and total landings have halved over the last 30 years. The highest fishing impact took place in the late 1990s, with a clear decrease in stock-based and ecosystem indicators. In particular, trophic-based indicators exhibited a continuous decreasing trend in almost all ecosystems. Over the past decade, a decrease in fishing pressure has been observed, the mean fishing mortality rate of assessed stocks being almost halved in all the considered ecosystems, but no clear recovery in the biomass and ecosystem indicators is yet apparent. In addition, the mean recruitment index was shown to decrease by around 50% in all ecosystems (except the Baltic). We conclude that building this kind of diagnosis is a key step on the path to implementing an ecosystem approach to fisheries management
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Goetze, J., Langlois, T., Claudet, J., Januchowski-Hartley, F., & Jupiter, S. D. (2016). Periodically harvested closures require full protection of vulnerable species and longer closure periods. Biol. Conserv., 203, 67–74.
Résumé: Periodically harvested closures (PHCs) are small fisheries closures with objectives such as sustaining fisheries and conserving biodiversity and have become one of the most common forms of nearshore marine management in the Western Pacific. Although PHCs can provide both short-term conservation and fisheries benefits, their potential as a long-term management strategy remains unclear. Through empirical assessment of a single harvest event in each of five PHCs, we determined whether targeted fishes that differ in their vulnerability to fishing recovered to pre-harvest conditions (the state prior to last harvest) and demonstrated post-harvest recovery benefits after 1 year of re-closure. For low and moderately vulnerable species, two PHCs provided significant pre-harvest benefits and one provided significant post-harvest recovery benefits, suggesting a contribution to longer-term sustainability. PHCs with a combination of high compliance and longer closing times are more likely to provide fisheries benefits and recover from harvest events, however, no benefits were observed across any PHCs for highly vulnerable species. We recommend PHCs have longer closure periods before being harvested and species that are highly vulnerable to fishing (e.g. large species of; grouper, wrasse and parrotfish) are avoided during harvests to avoid overexploitation and increase the sustainability of small-scale fisheries. (C) 2016 Elsevier Ltd. All rights reserved.
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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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Goetze, J. S., Januchowski-Hartley, F. A., Claudet, J., Langlois, T. J., Wilson, S. K., & Jupiter, S. D. (2017). Fish wariness is a more sensitive indicator to changes in fishing pressure than abundance, length or biomass. Ecol. Appl., 27(4), 1178–1189.
Résumé: Identifying the most sensitive indicators to changes in fishing pressure is important for accurately detecting impacts. Biomass is thought to be more sensitive than abundance and length, while the wariness of fishes is emerging as a new metric. Periodically harvested closures (PHCs) that involve the opening and closing of an area to fishing are the most common form of fisheries management in the western Pacific. The opening of PHCs to fishing provides a unique opportunity to compare the sensitivity of metrics, such as abundance, length, biomass and wariness, to changes in fishing pressure. Diver-operated stereo video (stereo-DOV) provides data on fish behavior (using a proxy for wariness, minimum approach distance) simultaneous to abundance and length estimates. We assessed the impact of PHC protection and harvesting on the abundance, length, biomass, and wariness of target species using stereo-DOVs. This allowed a comparison of the sensitivity of these metrics to changes in fishing pressure across four PHCs in Fiji, where spearfishing and fish drives are common. Before PHCs were opened to fishing they consistently decreased the wariness of targeted species but were less likely to increase abundance, length, or biomass. Pulse harvesting of PHCs resulted in a rapid increase in the wariness of fishes but inconsistent impacts across the other metrics. Our results suggest that fish wariness is the most sensitive indicator of fishing pressure, followed by biomass, length, and abundance. The collection of behavioral data simultaneously with abundance, length, and biomass estimates using stereo-DOVs offers a cost-effective indicator of protection or rapid increases in fishing pressure. Stereo-DOVs can rapidly provide large amounts of behavioral data from monitoring programs historically focused on estimating abundance and length of fishes, which is not feasible with visual methods.
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