Coastal Aquaculture in Portugal

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1 Regional Aquaculture Conference 2014, 9-11 December, Bari, Italy Blue Growth in the Mediterranean and the Black Sea: Developing Sustainable Aquaculture for Food Security IMTA in earthen ponds Coastal Aquaculture in Portugal Year 2012 Area of Licensed Entreprises hectars 11 t 1% Seabass Seabream Others 9 h 1% Freshwater Brackish/Marine 486 t 46% Improving land based aquaculture development and environmental protection by using Integrated Multi-Trophic Aquaculture (IMTA) in earthen ponds 327 h 21% 1574 h 99% Non active Active 343 h 28% 124 h 10% 338 t 9% 735 t 19% 780 h 62% Extensive Intensive Semi-intensive 9 t 0% 555 t 53% Clams Cockles Mussels Oysters Others Maria Emília Cunha (micunha@ipma.pt) Hugo Quental Ferreira, Florbela Soares, Domitília Matias, Sandra Joaquim, Laura Ribeiro, Pedro Pousão Ferreira Estação Piloto de Aquacultura de Olhão, Portugal 1247 h 79% 449 t 11% 2394 t 61% 1

2 The facts: - Specially adapted salt ponds are the main aquaculture fish production systems in Portugal - Production is usually in semi-intensive conditions (1.5 to 3 kg m 3 ) - Profitability is low given the costs of energy, feed and labour The results: IMTA in earthen ponds Coastal Aquaculture in Portugal - Abandon of the activity lead to lost of landscape and wet habitat for migratory birds due to the sedimentation of the ponds and/or real estate invasion. IMTA in earthen ponds Why not Integrated Multi-Trophic Aquaculture in earthen ponds? Better water quality plants and microalgae absorbing nutrients Water quality more stable predators eating algae Less stress on fish etc. Less chance of disease Better fish quality Better prices for products Less nutrients in effluents 2

3 Aquaculture with supply of inert feeds (fish) IMTA in earthen ponds Integrated MultiTrophic Aquaculture in earthen ponds + Extractive Aquaculture Organic Inorganic (Bivalves) (Algae) Our main Questions 1.Best combination of fish species? Eutrofization (nutrients) = Particulate Organic Mater (POM) + Dissolved Inorganic Mater (DIM) Particulate Organic Mater (POM) + Dissolved Inorganic Mater (DIM) 2.Best grow-out structures for oysters in IMTA? 3.How will oysters affect the system? 4.Will oysters achieve acceptable growth performance? 5.Will the sanitary quality of oysters be acceptable? 3

4 Trial Experimental period: May 2010 to February 2011 EVALUATE: Fish growth and stomach content Best oyster grow-out structure Sea cucumber adaptation - 6 ponds of 750 m 3 - IMTA vs Polyculture - 2 treatments in triplicates Trial Comparative performance of three grow-out structures for oysters Baskets Trays Five bream species Crassostrea angulata Holothuria tubulosa 189 Kg/pond 75 Kg/pond 42 Kg/pond 5 baskets/pond 100 oysters/basket Mesh bags 5 trays/pond 100 oysters/tray Polyculture proportion 5 bags/pond 250 oysters/bags 4

5 Trial Experimental period: May 2011 to November 2012 Our main Questions EVALUATE: Water quality Oysters species comparison Benthic diversity seabreams/pond (Mean weight of 7,1g) oysters/pond for biofiltration (Mean weight of 50g) - Seeds of C. angulata and C. gigas (Mean weight of 0,6g) 1. Best combination of fish species? 2. Best grow-out structures for oysters in IMTA? 3. How will oysters affect the system? Rafts 4. Will oysters achieve acceptable growth performance? 5. Will the sanitary quality of oysters be acceptable? 5

6 Q1: Best combination of fish species? Fish growth performance Q1: Best combination of fish species? Comparative analysis of fish stomach content 6

7 Our main Questions 1. Best combination of fish species? Q2: Best grow-out structures for oysters in IMTA? Mesh bags 2. Best grow-out structures for oysters in IMTA? 3. How will oysters affect the system? 4. Will oysters achieve acceptable growth performance? 5. Will the sanitary quality of oysters be acceptable? 7

8 Mean concentration (µg/l) 19/12/2014 Our main Questions Q3: How will oysters affect the system? Experimental period: May 2011 to November Best combination of fish species? No strong effect of oysters. Probably not enough biofiltration. 2. Best grow-out structures for oysters in IMTA? 3. How will oysters affect the system? 4. Will oysters achieve acceptable growth performance? 5. Will the sanitary quality of oysters be acceptable? 8

9 Q3: Will oysters affect the system? Our main Questions Bottom quality: Benthic Fauna (M-AMBI Index ) Benthic diversity in IMTA ponds significantly higher than monoculture system. 1. Best combination of fish species? 2. Best grow-out structures for oysters in IMTA? 3. How will oysters affect the system? 4. Will oysters achieve acceptable growth performance? 5. Will the sanitary quality of oysters be acceptable? 9

10 Live weight (g) Cumulative mortality (%) 19/12/2014 Q4: Will oysters achieve acceptable growth performance? C. gigas reaches size 3 class (65-85 g) in 12 months and C. angulata in 15 months Autumn Winter Spring Summer Q4: Will oysters achieve acceptable growth performance? Higher mortality for the Pacific oyster (2x higher than Portuguese oyster) Autumn Winter Spring Summer Initial weight 0.6 g Pacific oyster Commercial Sizes Size 4 Size 5 Pacific oyster Portuguese oyster Time (days) Size 5: 30-45g Size 4: g Size 3: g Size 2: g Size 1: g Size 0: > 150 g Time (days) Pacific oyster oyster Portuguese Portuguese oyster oyster 10

11 Our main Questions 1. Best combination of fish species? 2. Best grow-out structures for oysters in IMTA? 3. How will oysters affect the system? 4. Will oysters achieve acceptable growth performance? Q5: Will the sanitary quality of oysters be acceptable? Better microbiological quality of the IMTA oysters compared to Ria Formosa lagoon Microbiological quality in IMTA ponds Harvesting prohibited C B A Microbiological quality on a bed outside EPPO Harvesting prohibited C B A 5. Will the sanitary quality of oysters be acceptable? A Ready for consumption B Purification, relaying or cooking by an approved method C Relaying or cooking by an approved method (Annex II, Chapter II of Regulation (EC) 853 and 854/2004, as amended by Regulation (EC) 1021/2008) 11

12 Main conclusions Acknowledgements Pacific oyster growth better but avoid peak summer when mature Oysters growth acceptable but mortality rate must be lower Oysters are good for benthic diversity and remineralization Sea cucumbers may not withstand peak summer temperatures 12