Towards An Integrated Ecosystem Based ManagementPresentation Transcript
Towards an integrated ecosystem-based management: What is necessary in Chile? JC Quiroz División de Investigación Pesquera Instituto de Fomento Pesquero email@example.com Using Target and Limit Reference Points in Low-Trophic Level Fisheries
Small-pelagic fisheries Anchovy northern
Anchovy and common sardinecentral-southern
TheChileanfisheriesmanagement (1/2) The small-pelagic case The exploitation strategies have been done through annual Total Allowable Catches (TAC's) Based on reference fishing mortality Using an overall exploitation criterion P(Ft>F60%)<0.1 Two reviewing TAC processes a year
January Recruitment surveys Stock Assessment anchovy common sardine April-May Autumn surveys
TheChileanfisheriesmanagement (2/2) Others important low-trophic level fisheries Crabs, squat lobsters and shrimps species December agreement on the TAC’s Based on reference exploitation rate (µ=Y/B) Using an overall exploitation criterion P(µt>[0.12-0.17])<0.1 (decline biomass) P(µt>[0.12-0.17])<0.5 (stable biomass)
… has been done via only mono-specific stock assessment models and trend over the surveys biomass estimates Nevertheless, several papers have called attentionabouttrophic interactions and community structure of commercial fishery species off Chile But, some drawbacks emerge … Until now, the management …
Neira et al. (2004)Ecological Modelling The problem is: “Searching the Ecopath ratios” In Chile, the knowledge on fundamental P/B, Q/B, EE, DC ratios is fragmentary at best
Predation-preyinteraction Impacts of both fishing and Dosidicusgigaspredation on the projections of Chilean hake…What about the cycles and the correlation-time structure?
While these work undoubtedly will contribute to the knowledge ecosystem, it is still necessary to guide them towards a common goal, the Ecosystem Approach to Fisheries (EAF) How it can be put into practice?
Developing Ecological Indicators for Fisheries Management From scientific observer and monitoring programs Cath, effort, length, reproduction, by-catch, misreport, species proportion, etc. Target and not-target species Others observations number of dead birds caught in longline whalesighting
Developing Ecological Indicators for Fisheries Management From fishery-survey methods Acoustic (small-pelagics, others pelagics, demersal) Trawl (crustaceans) fishery-independent time series data Aggregations’ measurements Biological data (larval, length, weight, sex by specie) Acoustic characterization of the aggregations Oceanographic data
… two purposes are identified to managing the impacts of ﬁshing on marine ecosystem: performance measurement of themanagement objetives It can be used as a part of decision rules to determine adaptive management Ecological indicators … Fulton, E. A., Smith, A. D. M., and Punt, A. E. 2005. Which ecological indicators can robustly detect eﬀects of ﬁshing? e ICES Journal of Marine Science, 62: 540-551.
… Is necessary an Integrated Ecosystem Monitoring , Diagnostic and Evaluation (like single-species ﬁshery management , these represent my own view)