UR EU

Upwelling Ecosystems (Écosystèmes d’upwelling): 

Upwelling Ecosystems (Écosystèmes d’upwelling) Structure and functioning of upwelling ecosystems, under global change

IRD Members: 

IRD Members

Students: 

Students

Main partnership: 

Main partnership Canary INRH Machu Humboldt IMARPE Bertrand, Gerlotto Benguela UCT MCM Drapeau, Lett, Penven Brest IRD-Ifremer Roy Sete CRHMT Fréon, Cury, Shin, Demarcq Saint Quentin UVSQ Mullon

From IDYLE and ACTIVE to ECO-UP: 

From IDYLE and ACTIVE to ECO-UP IDYLE Question: How adaptive strategies of pelagic population do depend on the physical and biological dynamics of upwelling systems ? Field: Benguela Approach:Modelling, GIS Themes:Hydrodynamic modelling, IBM, GIS, remote sensing, retrospective analysis Effectif: 5 scientists Locations:Le Cap, Sète, Brest ACTIVE Question: What is the effect of the behaviour of pelagic fish about their catcahability ? Field :Humboldt Approach: Acoustic surveys, modelling, data analysis Themes: aggregative behaviour (tunas, FAD, schools and clusters of small pelagics), spatial structuring of pelagic habitat (tuna) IRD Staff: 9 scientists Locations:Valparaiso, La Réunion, Seychelles, Sète ECOSYSTEMES D’UPWELLING Question: What are the effects of global changes on worldwide upwelling ecosystems? Field :Humboldt, Benguela, Canary Approach:Comparative, Intégrated Themes:Climate et hydrodynamics, productivity, hydrodynamics and ecology, trophic structures, eco-ethology of pelagic systems, fisheries economics Staff:13 scientists Locations: Sète, Le Cap, Lima, Casablanca, Brest, Saint Quentin

Structure of the project: 

Structure of the project Field studies : Benguela Canaries Humboldt Scientific themes: Climate, environment, hydrodynamics and transport production, fish populations, fisheries Partnership EUR-OCEANS GLOBEC-SPACC BCLME PNEC BENEFIT ATI-HUMBOLDT Teaching Doctoral schools (UCT, Montpellier 2), UBO Brest (Sciences de la mer), VAS-ENSAR, Concepcion Chili, Université de Dakar) Summer schools 11 PhD students

Comparative approach: 

Comparative approach Benguela Humboldt Canaries (Californie)

Comparative approach: 

Comparative approach Subjets Reproductive strategies Regime shifts Spatial dynamics Productivity turn-over Relationships between topography and dynamics Importance of large predators and fishing Scales Spatial extension (the whole system) (1500km x 300km) Spatial grid : From méso-scale to sub-meso-scale (~2 à 20 km) Time extension : Decennial (regime shifts) Time step : form 2 days to year

Climate and physics: 

Climate and physics Hydrodynamics ROMS 25 km 5 km 1 km

Physics and ecology: 

Physics and ecology Transport Lagrangian approaches Bakun’s triad

Biological production: 

Biological production NPZD Chlorophyll a) NPZD b) SeaWIFS

Fish communities: 

Fish communities Trophic structure EwE OSMOSE Viability approach

Fish communities: 

Fish communities Trophic structure Illustration of our approach Question : Regime shifts Hypothesis : Nature of ecological controls (Top Down, Bottom Up, Wasp- Waist) A tool : Ecosystem modelling An expected result : Indicators of ecosystem functioning

Fish communities: 

Fish communities Trophic structure GIS

Fish communities: 

Fish communities Eco-Ethology Spatial behaviour: of pelagic populations (schools, clusters) of plankton (patches, 3d) of fleets as indicators of ecosystems regimes

Fisheries: 

Fisheries Towards an integrated model of the worldwide system of small pelagic fisheries

Canary: 

Canary Responsible : Eric Machu Partners : INRH (Maroc), LPA (Sénégal), JRC (Italie), Université d’Alveiro (Portugal), LPO (France), LEMAR (France), US ACAPPELLA (France), US 025 (France) Specific questions Latitudinal gradient Importance of the shelf Ecosystem shifts Fisheries Iron and storms

Humboldt: 

Humboldt Responsible : A. Bertrand Partners: IMARPE, University of San Marcos (Peru); IFOP, University of Concepcion, INPESCA (Chili); Questions ENSO Productivity Relationship between primary production and pelagic production

Benguela: 

Benguela Responsible : L. Shannon, L. Drapeau Partners : M&CM (South Africa), University of Cape Town (South Africa), BCLME (Angola, Namibia, South Africa) Questions Connexion Indian Ocean / Atlantic Ocean Distance between spawning and nursery areas Differences North/South

Expected results: 

Expected results Methodology: towards the  Ecoscope of upwelling ecosystems Generic tools for LME Indicators for EAF Atlas on line of upwelling ecosystems

Funding: 

Funding IRD 13 full time positions 130.000 euros/year 3 PhD/year French scientific programs PNEC (16.000 euros/year) ANR (30.000 euros/year) European scientific programs Euroceans (3 PhD/year)

Schedule: 

Schedule 2004, From January to June : Submitting the project 2004, November : Cape Town meeting, focus on scientific questions 2005-2008 : Carrying out the project: implementation of different approaches on the 3 ecosystems; implementation of the Atlas on line

Slide23: 

Time table a- grangian, IBM, Eco - éthology surveys, V i ability, GIS ROMS, BCLME Synthesis All Watching sy s- tem Time series, Bio - éco nomy., Book (1) Watching system, Sp a tial indicators, EwE, Time series, Bio - eco, Book (2) Climate change scenarios, Comparative anal y sis, Book (2) Synthesis — To be done — Done

Keywords: 

Keywords Comparative approach Integrated approach Structure and functionning Change

APPENDICES: 

APPENDICES

Cape Town – November 2004Method: 

Cape Town – November 2004 Method Climate and hydrodynamics: large scale Climate and hydrodynamics: meso-scale Production: bottom up Trophodynamics: Trophic structure Eco-ethology Application to EAF, implications for operational oceanography Structure/Functioning Change Operational Oceanography Comparison

Classified questions (1): 

Classified questions (1) Climate and hydrodynamics: large scale Are there regimes in the circulation and atmospheric dynamics of the upwelling systems? Are there global climate features that explain the synchrony between the pelagic stocks throughout the world? What are the regime shifts in the Benguela (spatial) and Humboldt (temporal) in climate change? What are the triggers? What maintain them? What is the regional impact of climate change in upwelling systems, e.g. on its structure? Climate and hydrodynamics: meso-scale What are the determinants of meso-scale activities in upwelling systems? Is it the position of the upwelling front? What are the forcing factors? What is the importance of mesoscale structures (e.g. filaments, eddies, cool ridges, upwelling front etc)? How to characterize them, spatially and dynamically? What is their variability? Production: bottom up What is the magnitude of interannual variability of primary production? What causes it? How to relate intra- and interannual variability? What is the temporal scale of events: blooms, collapse? Which nutrient(s) limits the production in upwelling systems? Are upwelling systems food limited or nutrient limited, is the transfer efficiency similar? For example, why the Humboldt system is thought to be food limited?  

Classified questions (2): 

Classified questions (2) Trophodynamics: Trophic structure How can we incorporate ecosystem considerations into fishing sectors management? How can we quantify the effect of human activity on structure and functioning of the ecosystem? How to reconcile single species and multispecies management approaches? What is the role of fishing in driving regime shifts? What is the role of trophic interactions in the success of recruitment? Does the length of their food chains characterize the different ecosystems? How can we characterize the role of a species in a foodweb? How do we account for the high/low pelagic fish biomass in the various upwelling systems e.g. southern/northern Benguela? How to characterize the types of controls, and the switch between them? Do the trophic controls depend on the trophic level? What are the implications of spatial distributions (horizontal and vertical) in trophic interactions?  

Classified questions (3): 

Classified questions (3) Eco-ethology How gregarious fish manage the multi-scale environmental variability intrinsic of upwelling ecosystems How collective fish structures can be indicators of fish interactions with their environment and ecosystem status; this requires answer to a more specific question: what are the behavioural mechanisms allowing the organisation of collective structures What are the determinisms of fish cluster size, number and dynamics: population versus environmental factors (eddies, etc.) What are the interactions between predators (natural or fishers) and pelagic fish in terms of spatial organisation How can we integrate eco-ethological process in the adaptative management of resources in an EAF framework How the energetic inputs in a hierarchical system are transmitted across multi-scale physical and biological organisation levels and shape fish and predators (fishers included) spatial organisation How can we characterise the spatial and dynamic scale-invariant patterns in hierarchical structured upwelling ecosystems  

Classified questions (4): 

Classified questions (4) Application to EAF, implications for operational oceanography How can operational oceanography contribute to EAF? (Feedback between what operational oceanography can provide and what EAF requires and can use). How can we build indicators that are amenable to management? What are the consequences of regime shifts in fisheries management? What are the relevant real-time indicators of changes and variability? What indicators are requested for the management of an unstable resource? Which indicators are relevant in that context?