The Sphere of Action Research Developed with the support of Balfegó Group ( ).

Transcription

1 The Sphere of Action Research Developed with the support of Balfegó Group ( ). Ana Gordoa Centro de Estudios Avanzados de Blanes (CEAB) CSIC

2 Research Cooperation begun in 2008 Objective: to determine if tuna spawning took place in tuna transport cages. Method: an innovative sampling design was successfully implemented Results: The first time ever the spawning of Atlantic Bluefin was observed It could determine the time of day when spawning takes place. The consistency and regularity of spawning within tuna transport cages open a new line of research. Tuna transport cages become research platforms

3 Fundamental Research (FR) Reproduction of Atlantic bluefin tuna (ABFT): temporal pattern in Balearic waters Spawning temporal pattern Spawners (reproducers) temporal pattern Egg and early larvae development Genetic analysis between eastern and western Mediterranean ABFT spawners Growth rate in captivity Applied Research (AP) Implications of FR Results in the current policy - Adequacy of the current purse seine fishing season Implications in the estimations of annual catch rates (CPUE).

4 Spawning : temporal pattern Spawning Survey : Descriptors Component/research platform: transport cages Elements: 1. The first wild tuna caught in the fishing season 2. Captive tuna caught in 2008 (experimental group) Period : mid May mid July Frequency: daily Years: 2008-

5 Graphic description of the sampling methodology Transport cage

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7 Night sampling Sampling nets

8 Filtered Samples Preserved Samples eggs

9 On board aquaculture experiments ABFT larvae

10 The Environment A new Research Line: Yellyfish spatio-temporal match and impact on ABF spawning Recently included in the European Master in Marine Biodiversity and Conservation (

11 Spawning Results 1000 Daily Spawning Pattern (2009 survey) 2:00-3:00 local time 3:00-4:00 local time ºc /05/09 25/05/09 27/05/09 29/05/09 31/05/09 02/06/09 04/06/09 06/06/09 08/06/09 10/06/09 12/06/09 14/06/09 16/06/09 18/06/09 20/06/09 22/06/09 24/06/09 26/06/09 28/06/09 30/06/09 02/07/09 04/07/09 06/07/09 08/07/09 10/07/09 12/07/09 14/07/09 16/07/09 18/07/09 20/07/09 Eggs volume (ml)

12 Daily cumulative spawning (based on 2009 and 2010 surveys) Impact on recruitment of the Present Fishing season Estimations based on 2010 Spanish cuota. Potential reduction above recruits Closed fishing season 2010 Cuota filled 24-May 26-May 28-May 30-May 1-Jun 3-Jun 5-Jun 7-Jun 9-Jun 11-Jun 13-Jun 15-Jun 17-Jun 19-Jun 21-Jun 23-Jun 25-Jun 27-Jun 29-Jun 1-Jul 3-Jul 5-Jul 7-Jul 9-Jul 11-Jul 13-Jul 15-Jul 17-Jul 19-Jul 21-Jul Cumulative Spawning (%)

13 2,0 Spawners (reproducers) temporal pattern - through purse seine catch rates. 1,8 1,6 1,4 1,2 1,0 0,8 0,6 0,4 0,2 Mean coefficient of abundance 0, mayo mayo mayo mayo 1-5 junio 6-10 junio junio junio junio junio 1-5 julio 6-10 julio julio Higher temporal abundance Higher ecoeficiency (*)

14 Fundamental Research (FR) Reproduction of Atlantic bluefin tuna (ABFT): temporal pattern in Balearic waters Spawning earliest temporal pattern : Peak spawning June Spawners (reproducers) temporal pattern : Peak abundance : June Applied Research (AP) Implications of FR Results in the current policy (15 June fishing is closed) Spawning of the harvested cuota is inhibited impact on the population Higher effort to fill the cuota higher costs and CO2 emissions ecommendation : fishing season should be regionally adapted based on the pawning periods of the eastern, central and western Mediterranean. Implications in the estimations of annual catch rates (CPUE).

15 Balfego Catch rates (kg/day) : CPUE (kg/day) Baleares: Balfegó CPUE until 8th June: Balfegó CPUE (8th June)(L) CPUE Balfego(R) 20 june CPUE until 8th June (kg/day) july 30 june 13 june 8 june CPUE total spawning period (Kg/day) The positive trend in the most recent years has also been observed in: Moroco traps, Spanish traps, Japenese Long line fleet and juveniles from French aerial surveys.

16 Published studies with the direct support of Balfegó Group Gordoa, A, Olivar, MP, Arevalo, R., Viñas, J., Molí, B., Illas, X Determination of Atlantic bluefin tuna (Thunnus thynnus) spawning time within a transport cage in the western Mediterranean. ICES Journal of Marine Science. 66, Gordoa, A Temporal pattern of daily CPUE on the Atlantic bluefin tuna (Thunnus thynnus) in the western Mediterranean spawning area. ICCAT SCRS/2009/156. Gordoa, A The Atlantic Bluefin Tuna: Study of the Temporal Pattern of Spawning in the Western Mediterranean Region and Reproductive Capacity in Captivity. ICCAT SCRS/2009/157. Gordoa, A An indirect Approach to estimate the Fattening Factor of Atlantic Bluefin Tuna (Thunnus thynnus) on Tuna Farms: Ametlla de Mar Facility as a Case Study ICCAT SCRS/2009/158. Gordoa, A Estudio del Patrón anual de la CPUE del Atún Rojo (Thunnus thynnus) en la región Balear y factores de distorsión: Flota Balfegó SCRS/2010/097. Gordoa, A Aproximación al Impacto sobre el Reclutamiento del Atún Roj (Thunnus thynnus) de las Capturas de Cerco en Baleares con el Actual Periodo de Veda. SCRS/2010/107. Viñas, J., Gordoa, A., Fernández-Cebrian, R., Pla, C., Ünal, V., Araguas, R.M Facts and uncertainties about the genetic population structure of Atlantic bluefin tuna (Thunnus thynnus) in the Mediterranean. Implications for fishery management. Rev. Fish. Biol. Fisheries (in press).

17 Thank you