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GFCM SCSA, Izmir 22-26 Sept 2008Sardine GSA01 Bellido et al Fishery Assessment of Sardine Stock GSA01 (Northern Alboran) Bellido, J.M. 1, Quintanilla,

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Presentation on theme: "GFCM SCSA, Izmir 22-26 Sept 2008Sardine GSA01 Bellido et al Fishery Assessment of Sardine Stock GSA01 (Northern Alboran) Bellido, J.M. 1, Quintanilla,"— Presentation transcript:

1 GFCM SCSA, Izmir 22-26 Sept 2008Sardine GSA01 Bellido et al Fishery Assessment of Sardine Stock GSA01 (Northern Alboran) Bellido, J.M. 1, Quintanilla, L. 2, Giráldez, A. 2, Torres, P 2., Ceruso, C. 1, Alemany, F. 3, Iglesias, M. 3 1 Instituto Español de Oceanografía. Centro Oceanográfico de Murcia. C/ Varadero 1. San Pedro del Pinatar. 30740. Murcia. Spain. 2 Instituto Español de Oceanografía. Centro Oceanográfico de Málaga. Puerto Pesquero s/n. Apdo 285. Fuengirola. 29640. Málaga. Spain. 3 Instituto Español de Oceanografía. Centro Oceanográfico de Baleares. Muelle del Poniente s/n. Apdo 291. Palma de Mallorca 07015. Spain.

2 GFCM SCSA, Izmir 22-26 Sept 2008Sardine GSA01 Bellido et al Introduction Fishery assessment by VPA methods of the Spanish sardine stock GSA01. VPA Lowestoft software suite was used and XSA was the assessment method. A separable VPA was also run as exploratory analysis for both stocks. Stochastic short term projections were also produced.

3 GFCM SCSA, Izmir 22-26 Sept 2008Sardine GSA01 Bellido et al Landings and sampling ports (in blue) GFCM GSA-01 Northern Alboran

4 GFCM SCSA, Izmir 22-26 Sept 2008Sardine GSA01 Bellido et al Assessment Data GSA01 Landings time series 2000-2007. ALK 2003-2006, combined ALK for 2000-2002. Length Distributions 2003-2007, combined for 2000-2002. Biological sampling 2003-2007 for Maturity at age and Weight-Length relationships. Tuning data from acoustic survey ECOMED and Commercial Fleet off Estepona, Málaga and Adra.

5 GFCM SCSA, Izmir 22-26 Sept 2008Sardine GSA01 Bellido et al XSA Input Data GSA01

6 GFCM SCSA, Izmir 22-26 Sept 2008Sardine GSA01 Bellido et al XSA Input Data GSA01

7 GFCM SCSA, Izmir 22-26 Sept 2008Sardine GSA01 Bellido et al Assessment Model Separable VPA – as Exploratory tool. VPA - XSA (Extended Survivors Analysis) as assessment tool.

8 GFCM SCSA, Izmir 22-26 Sept 2008Sardine GSA01 Bellido et al Diagnostics Separable GSA01 Log catchability residual plots. Some conflict between ages seem to appear. Fleet behaviour and fishery movements could affect the catchability pattern.

9 GFCM SCSA, Izmir 22-26 Sept 2008Sardine GSA01 Bellido et al XSA Assessment Main Settings XSA: Fbar 1-3. Age 2 for q stock-size independent and age 3 for q independent of age. Fshrinkage = 0.500 and S.E. for fleet terminal estimates ≥ 0.300 XSA Diagnostics. Residuals by Fleet. Estimations of Survivors by age and fleet.

10 GFCM SCSA, Izmir 22-26 Sept 2008Sardine GSA01 Bellido et al Fleet Diagnostics GSA01 Minimun (from ECOMED) Maximun (from ECOMED) Minimun (from ECOMED) Maximun (from ECOMED) Minimun (from ECOMED) Maximun (from ECOMED)

11 GFCM SCSA, Izmir 22-26 Sept 2008Sardine GSA01 Bellido et al Estimated Survivors by Fleet GSA01

12 GFCM SCSA, Izmir 22-26 Sept 2008Sardine GSA01 Bellido et al Estimated Survivors by Fleet GSA01

13 GFCM SCSA, Izmir 22-26 Sept 2008Sardine GSA01 Bellido et al Estimated Survivors by Fleet GSA01

14 GFCM SCSA, Izmir 22-26 Sept 2008Sardine GSA01 Bellido et al Results – Stock Summary GSA01

15 GFCM SCSA, Izmir 22-26 Sept 2008Sardine GSA01 Bellido et al Short term projections Deterministic Projections for three years (2008 to 2010). MFDP software (Multi-Fleet Deterministic Projections). Settings: Recruitment Geometric mean: GSA01 - R 2007 = 228 millions. F statu quo is Fishing Mortality Average last three years and Reference ages 1-3, i.e. average Fbar last 3 years. GSA01 – Fstatu quo = 0.28.

16 GFCM SCSA, Izmir 22-26 Sept 2008Sardine GSA01 Bellido et al Results GSA01 Short term projection

17 GFCM SCSA, Izmir 22-26 Sept 2008Sardine GSA01 Bellido et al Conclusions - Assessment Landings decrease in 2007, reaching up 6,770 t. The time series shows a rather fluctuating trend, with the lowest value in 2004 (3,960 t) and the greatest in 2006 (10,000 t). Fishing mortality is at a moderate level (F 07 =0.26), showing a rather stable trend. Recruitment in 2007 decreases from that of previous years (R 07 =228 millions), showing the lowest value of the time series. The time series recruitment shows a decreasing pattern. Both Total biomass in 2007 (TB=32,300 t ) and Spawning Stock Biomass in 2007 (SSB=28,800 t) decrease with respect to 2006, although they are still over the lowest SSB in 2000 (Bloss=22,100 t).

18 GFCM SCSA, Izmir 22-26 Sept 2008Sardine GSA01 Bellido et al Conclusions – Catch Forecasting statu quo F (F bar05-07 =0.28) and (R 07 =228 mill): landings are predicted to be 5,800 t in 2008 and 5,000 t in 2009 t. Total biomass will decrease from 27,400 t in 2008 to 21,600 t in 2010 SSB will also decrease from 23,700 t in 2008 to 18,000 t in 2010. This exploitation pattern of maintaining F statu quo 2008- 10, with scenarios of low recruitment rates, could prompt a decline of the fishery with SBB scenarios under current Bloss. In this situation it is particularly important to pay special attention to recruitment levels as they could prompt sudden increases or drops in a near future.

19 GFCM SCSA, Izmir 22-26 Sept 2008Sardine GSA01 Bellido et al Conclusions - Management considerations No reference points can be suggested at this point. Further years will come an extension of the assessment time series suitable to suggest Reference Points and Harvest Control Rules. This fishery is considered as fully exploited. Under this scenario we consider fishing effort should not increase beyond the current levels. This should allow not to increase (or at least to maintain) the current levels of Fishing mortality.

20 GFCM SCSA, Izmir 22-26 Sept 2008Sardine GSA01 Bellido et al Further work Reference points. Harvest Control Rules.

21 GFCM SCSA, Izmir 22-26 Sept 2008Sardine GSA01 Bellido et al Thanks for your attention. Comments are welcomed. Dr. Jose Mª Bellido (josem.bellido@mu.ieo.es)


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