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Main exploited ecosystems in the GFCM area

Main exploited ecosystems in the GFCM area. An attempt of classification Jordi Lleonart FAO. Ecosystem.

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Main exploited ecosystems in the GFCM area

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  1. Main exploited ecosystemsin the GFCM area An attempt of classification Jordi Lleonart FAO

  2. Ecosystem A spatio-temporal system of the biosphere, including its living components (plants, animals, micro-organisms) and the non-living components of their environment, with their relationships, as determined by past and present environmental forcing functions and interactions amongst biota. (one of the many definitions)

  3. Large Marine Ecosystem • Large Marine Ecosystems (LMEs) are regions of ocean and coastal space that encompass river basins and estuaries and extend out to the seaward boundary of continental shelves and the seaward margins of coastal current systems. • LMEs are characterized by distinct bathymetry, hydrology, productivity and trophic interactions. • 64 LMEs currently identified in the World • The GFCM area of competence includes two LMEs: • The Mediterranean sea (LME # 26) • Black sea (LME # 62)

  4. Identifying ecosystems in the Mediterranean sea Geographical criteria • 10 Statistical divisions (FAO) • 30 Geographical Subareas (GFCM)

  5. Related to the bottom Pelagic (including plankton) Demersal or benthic Soft bottoms Rocky bottoms Coralligenous Seagrass beds Related to the coast Littoral (including estuaries and lagoons) Neritic Oceanic Related to depth Coastal or littoral Shelf Slope Deep sea Identifying ecosystems in the Mediterranean sea Ecological criteria

  6. A possible classification • Pelagic, shelf • Pelagic oceanic • Coastal or littoral • Demersal, shelf, soft bottoms • Demersal, shelf, hard bottoms • Demersal, slope • Demersal, deep sea

  7. Target species Mainly small pelagics Sardine Anchovy Sardinella Spratt Other species Fishing gears Purse seine Pelagic trawl Towed gear Small driftnets Impacts of fishing Fishing of postlarvae and juveniles Overfishing Other impacts Pelagic, shelf (neritic?)

  8. Target Species Mainly large pelagics Tuna and tuna like Dolphinfish Pelagic sharks Non-target species Pelagic sharks Turtles Cetaceans Birds Fishing gears Drifnets Longlines Seines Impacts of fishing Mortality of non-target species Overfishing Other impacts Pelagic, oceanic

  9. Target species Many Non target species Monk seal Turtles Patellidae & other Seagrass Juveniles of many species Fishing gears Many (even forbidden) Impacts of fishing Fishing of juveniles Habitat destruction Other impacts Habitat destruction by Tourism Pollution Infrastructures Coastal or littoral

  10. Target species Many bony fish Shellfish Non-target species Seagrass Fishing gears Towed gears Nets Pots Impacts of fishing Ghost fishing (nets) Habitat destruction by towed gears Other impacts Demersal, shelf, soft bottoms

  11. Target species Many bony fish Corals Non-target species Corals Fishing gear Towed gears Impacts of fishing Poor selectivity Habitat destruction by towed gears Ghost fishing Other impacts Demersal, shelf, hard bottoms

  12. Target species Shrimps Large hake Non-target species Fishing gears Trawl Pots Longline Impacts of fishing Poor selectivity Overfishing Other impacts Demersal, slope

  13. Target species Shrimps Aristeus antennatus Aristeomorpha foliacea Other species Non-target species Alepocephalus rostratus Etc. Fishing gears Trawl Pots Impacts of fishing Habitat destruction Community changes Other impacts Waste Demersal, deep sea From 2005 “Members of the GFCM shall prohibit the use of towed dredges and trawlnets fisheries at depths beyond 1 000 m of depth”

  14. Principles of relevance to an ecosystem approach to fisheries (EAF)FAO Technical Guidelines for Responsible Fisheries 4(suppl. 2) • Avoiding overfishing • Ensuring reversibility and rebuilding • Minimizing fisheries impact • Considering species interactions • Ensuring compatibility (of legislations) • Applying the precautionary approach • Improving human well-being and equity • Allocating user rights • Promoting sectoral integration • Broadening stakeholders participation • Maintaining ecosystem integrity

  15. Avoiding overfishing • Overfishing affects almost all Mediterranean exploited ecosystems • Growth overfishing →improve selectivity • Recruitment overfishing → allow reproduction • Ecosystem overexploitation → decrease bycatch, discards, harmful gears. Maintain community structures. • In general: decrease F. Since F=q∙E, it means decreasing q and/or E

  16. Ensuring reversibility and rebuilding • Irreversible changes affect mainly the coastal and shallow ecosystems: seagrass and coraligenous [towed gears in sensitive areas] • Effectively protect endangered species (turtles, mammals, birds, sharks, and some other apical predators) [driftnets and surface longlines]

  17. Minimizing fisheries impact • Objective: remove only the target species minimizing: • Discards • By catch • Degradation of sensitive bottoms • Other induced mortality (ghost fishing) • Note: the points above are tautological, since they are consequences, not causes, of overfishing

  18. Considering species interactions • Trophic relationships are networks, not lines. The model “one predator – one prey”, so if we want the prey, the predator is our competitor, just kill it is too simple and does not work. Things are more complex (i.e. the predator can also feed on other predators or competitors of the prey). • Research (data and modelling) is needed

  19. Applying the precautionary approach Complexity Irreversible processes Uncertainty Difficulties of forecasting Danger to damage the ecosystem

  20. Instruments • Control selectivity and sizes • Regulate OU’s (fleets and gears) • Limit the effort • Eradicate damaging and aggressive gears (i.e. towed gears in sensitive areas) • Eradicate IUU fishing • Control areas • Closures • Implementing MPA’s

  21. More instruments • Scientific research • Getting data • Catch and effort • Biology and environment • Developping ecosystemic models, indicators and reference points • Stakeholders participation in an adaptive management framework • Enforcement of the existing rules

  22. Final considerations (1) • Facing overfishing1 • Let them grow • Let them spawn • Let the mega-spawners (BOFF) live • Protecting ecosystem • Maintain habitats • Maintain trophic pathways ________________________________________________________________________________________________ 1 Froese, R.- 2004. Keep it simple: three indicators to deal with overfishing. Fish and fisheries, 5:86-91

  23. Final considerations (and 2) • Fisheries management (TROM, EAF or whatever) does not mean not fishing, but fishing better. • The Mediterranean, and its fisheries, are complex systems, but research, advice and management are possible and they work (as it has been demonstrated).

  24. FTP sites • SCMEE http://www.cmima.csic.es/pub/SCMEE • SCSA ftp://cucafera.icm.csic.es/pub/SCSA

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