Project FAO-COPEMED Large Pelagics

Transcription

1 Project FAO-COPEMED Large Pelagics Xiphias glaudius (Linnaeus,178) COORDINATOR J.M DE LA SERNA (IEO - SPAIN) PARTICIPANTS M. TAWIL (MBRC-LIBYA), A. FENECH FARRUGIA (MCFS-MALTA), A.SROUR (INRH-MAROCCO), HATTOUR (INSTM-TUNISIA), J.M DE LA SERNA (IEO - SPAIN) PUBLISHER P. RIOJA (FAO -COPEMED)

2 RESULTS (Period ) 1. Enviromental and Hydrographic Description of area under study.. Fisheries description and its historical development. 3. Database of catch, effort and size distribution for each species, for each gear (Task I and II of ICCAT). 4. Biological parameters: 1. Biometric relationships of length-weigth for species, gear and area. Analysis of results.. Sex ratio for each range of size by species and gear. Comparative analysis. 3. Study of sexual maturity of bluefin tuna and swordfish through gonadosomatic index and histological analysis. 4. Growth studies of bluefin tuna through the determination of age from dorsal spine sections.. Preparation of Standardized Abundace Indices of bluefin tuna and swordfish using GLM. 6. Study of stock of bluefin tuna and swordfich through genetic analysis.. Study of by catches of large pelagics in the Mediterranean. 6. Relationship between enviroment and the catches of large pelagics utilizing different gears. Summary of Investigation. 7. Annual Reporst (), Final Gibraltar Report

3 Fisheries description: description and characteristics of fishing vessels and gear targeting bluefin tuna. LLJAP-Spain PS-Spain PS-Tunisia PS-Spain Bait Boat-Spain LL-Malta Vessels targeting bluefin tuna and swordfish with several fishing gears. Note the high heterogeneity among vessels Description and characteristics of the different gears targeting tuna TRAP-Libya

4 Fisheries description: description and characteristics of fishing vessels and gear targeting swordfish. Signal Bouée 7 à _8 m à mètres LLHB -Spain LLHB Malta Fil nylon N à 6 m ; fil N 1 ; hameçon :-4 Flag Set at every 6 hooks detected by radar Flo a t 4m 1. monopilo 1./1.6 monopilo 1.3 monopilo (.9x) Lenght 6m LLHB - Tunisia Artesanal - Morocco Ba it (m ac kerel /squid) Hook nº (Mustad hook- Norway) Vessels targeting bluefin tuna and swordfish with several fishing gears. Note the high heterogeneity among vessels Spanish, Tunisian and Maltese longlines targeting swordfish.

5 Task data (ICCAT): catches per species, country, gear and time-space distribution. Bluefin tuna catches for each country using different gears.

6 Task data (ICCAT): catches per species, country, gear and time-space distribution. 3 PS-Sp Number Country: Mc= Maroc Mt= Malta Lb= Libya Tn= Tunisia Sp = Spain It = Italy Fr = Francia Gr = Grecia HAND-Mc Gear: LL = Surface longline PS = Purse seine HAND = Hand line BB = Bait board Size No.= Number Size 1 HAND-Sp TRAP-Lb LLHB-Mt Number Size 3 1 LLHB-Lb Number Size Number Size Number Size TRAP-Tn PS-Tn number Size Number TRAP-Sp LH TUNEZ ARENAS Size Number Length distribution of bluefin tuna for each country using different gears.

7 Biometric relationships of lenth-weigth of bluefin tuna and swordfish for each fishery and area. Analysis of variation between different areas for each gear during same year. Comparison of bluefin tuna RW- LH relationships for several fishing gears and seasons. 3 RW (kg) RW (kg) LJFL (cm) Mor98 Trap Mor98 Hand Mor94 Hand Tun99 Trap Tun Ps Lib Trap Spa BB Key: E-4 * RW ^ E- * RW ^ E-4 * RW ^ ,74869E- * RW ^ E-6 * RW ^ E- * RW ^ * RW ^ LJFL (cm) Mor98 GN Spa87 LLHB Mor99 GN Mor99 GN Mor GN Key: E-7 * RW ^ 3..- E-6 * RW ^ E-6 * RW ^ E-6 * RW ^ E-6 * RW ^ 3.7 Comparison of swordfish RW- LJFL relationships for several fishing gears and seasons.

8 Sex ratio for different length classes of bluefin tuna and swordfish for each gear. Analysis of variation and similarities between different gears, time and area. Sex- ratio by length-class and approximate 9% confidence limits for the Spanish longline fishery and the Moroccan drift net fishery targeting swordfish. 1,1 1,9,8,7,6,,4,3,,1 LONGLINE_SP (N= 3646); DRIFT NET_MOR (N= 1193) length class propfem_sp ll9% up9% propfem_mor ll9% up9% LONGLINE (N=98) length class propfem ll9% ul9% PURSE SEINE (N= 169) length class propfem ll9% ul9% TRAP (N= 998) Sex- ratio by length-class and approximate 9% confidence limits for several gears targeting bluefin tuna in the Mediterranean Sea and Straits of Gibraltar length class propf em ll9% ul9%

9 Sex ratio for different length classes of bluefin tuna and swordfish for each gear. Analysis of variation and similarities between different gears, time and area. % % 8% N=198 9% 8% BFT- TRAP-Atl Spain % 6% % % 7% 6% % % BFT- TRAP-Med Libya 99 al % 3% % % 1% BFT- PS-Med Tunisia -1 BFT- LL-Med Malta -1 % % FL (cm) 19 Fl (cm) No.= No.= 47 % % % Length (cm) HEMBRAS 9 n= TALLA BFT- HAND-E. Gibraltar /Spain BFT- LL- Baleares Spain Fl (cm) FL(cm) Female ratios for each length class targeted by different gears Bluefin tuna.

10 Sexual Maturity(I): analysis of gonadosomatic indices of bluefin tuna targeted by different gears. Bluefin tuna Females GI variations (Spain, ) Females Bluefin tuna GI (Malta, ) GI GI FL (cm ) FL (cm) Female Bluefin tuna GI (Tunis,) GI in traps (Libya, ) IG 3 1 GI Longueur à la fourche (cm) FL Bluefin tuna gonodosomatic indices for different gears used in Spain, Malta, Tunisia and Libya.

11 Sexual maturity (II): determination of first sexual maturity of bluefin tuna and swordfish by histological analysis of gonads sampled from Spain- Balearics, Malta, Tunis and Libya. Prop. Mature (Females) 1,,9,8,7,6,,4,3,,1, LJFL (cm) Prespawning ovaries of bluefin tunas Prespawning female Spawning female 6 4 GSI 3 1 Postspawning female Histological analysis of gonad samples of bluefin tuna Months June July August T Males T Females S Females Histological analysis of gonad samples of swordfish.

12 Growth studies Age Length keys and evaluation of growth obtained from age determination of bluefin tuna caught by Spanish and Libyan, purseine and Maltese longline. 7 Fork length (cm) 17 1 El-Kebir et al. () Farrugia & Rguez-Cabello (1) Cort (1991) Compean & Bard (1983) Present Study Age (years) Section of a spiny ray from the first dorsal fry of a bluefin tuna of cm in length. (Course on cut and reading of bluefin tuna C.O de Málaga). Fork length (cm) Comparison of mean fork length by age obtained in the present and other studies based on vertebra reading 7 17 Rodriguez-Roda (1964) Mather & Schuck (196) (western Atlantic) 1 Olafsdottir & Ingimundardottir (3) Sella 199 Cort (1991) (spines) Present study Age (years)

13 Abundance Indices: elaboration and standardization of bluefin tuna obtained from Spanish, Morrocon and Tunisian traps LN(n/eff) Standardized CPUE series in number of fish for the Spanish BFT Trap fishery in the Straits of Gibraltar. Dashed lines indicate 9% confidence bands Year (number) CI 9% CI 9% LN(number/effort) Standardized CPUE series in number of fish for the Tunisian BFT Trap fishery in the Mediterranean Sea. Dashed lines indicate 9% confidence bands. Year LN CPUE Low er Upper

14 Abundance Indices: elaboration and standardization of swordfich captured by Moroccon gill nets and Spanish surface longlines in the Mediterranean Evolution of annual standardised abundance indexes, with upper and lower limits of confidence level at 9%. Swordfish gill nets. Marocco. lcpu1 cpu ucpu cpue (number) cpue (weight) year year low cpue cpue uppercpue low cpue cpue uppercpue Standardized CPUE index (and corresponding 9% confidence limits) in number of fish (upper panel) and weight (lower panel). Surface longline in the Mediterranean. Swordfish

15 Stock structure-genetic analysis of bluefin tuna caught by Spanish and Libyan traps, Maltese longline and Tunisian purse seine. Results indicate similar Mediterranean genetic origins. Neighbor-Joining tree using Kimura two-parameters distance of the 11 distinct sequences. Numbers in the internal branches showed bootstrap values higher than 7% after replicates. Calde I, II and III sequences are are usesd as references for their own clades Phylogenetic tree based upon the Neigbor-joining distance of the distinct sequences. The numbers on the branches show bootstrap values exceeding %. Neighbor-joining tree with Tamura-Nei distance ( =.7) of the 67 Bluefin tuna haplotypes. Values in the branches

16 By cath: identification and percentage of by catch caught by Spanish, Moroccan, Tunisian, Maltese and Libyan gear SWO-CATALUÑA, Sea ,% TUN SWO OTH,6% SHK % 3,% SWO-ALBORAN, Sea ,7% 4,%,1% 1,% SWO-BALEARIC, Sea 1999 TUN SWO OTH SHK 73,% 1,3% 1% 3,% TUN SWO OTH SHK especies asociadas SWO-M ALTA, Sea ,1% TUN SWO OTH 7,% SHK,% % Fig.Nº País: Mc= Marruecos Mt= Malta Lb= Libia Tn= Túnez Sp = España It = Italia Fr = Francia Gr = Grecia 4 3 Arte: LL = Palangre PS = Cerco HAND = Linea de mano BB = Cebo vivo By catches of surface longlines Spanish and Maltese.

17 By cath: identification and percentage of by catch caught by Spanish, and Maltese longlines; Moroccan gill nets and Libyan, Tunisian, Spanish and Moroccann traps. By-catch Tuna inby-catchin the Spanish the Swordfish Spanish Swordfish Longline Longline Fishery Fishery () (),3% 1,6%,%,1% 6,4%,% 93,3% 91,% Sw ordfish Tunnus alalunga Sharks Tunnus Thynnus Billfishes Tunas Katsuwonus pelamis OTH Percentage of species caught by the swordfish longline fishery in. SharksBy-catch in the Spanish Swordfish Longline Fishery (),6% 1,3% 9,8% Alopias vulpinus Isurus oxyrinchus Prionacea glauca Sphyrna 73,3% Specific composition of the sharks group in the Spanish swordfish fishery in 19% Tunissian Purseseiner By-catches (1) 18% 1% 1% 41% Auxis rochei Sarda sarda Orcynopsys unicolor Euthynnus alletteratus OTH Percentage (Weight) of the Tunisian purseiners by-catches (1). 4,%,7% Moroccan Drift Net By-catches,%,6%,1% 41,3% 1,% Sharks Makaira sp. Auxis thazard Euthynnus alletteratus Sarda sarda Katsuw onus pelamis Tunnus thynnus Percentage (Weight) of the by-catch species in the Morocco Drift Net Fishery. 1% % By-catch in the Malteese Bluefin Tuna Longline Fishery Tunnus alalunga 4% 1% % % 4% % Prionace glauca Alopias vulpinus Galeorhinus galeus Coriphaena hippurus Scomber scombrus Sarda sarda Rubetus pretiosus Percentage of the main by-catch species caught by the Maltese bluefin tuna longline fishery.

18 Enviromental studies-relationship between surface temperature and CPUE; relationship between wind and bluefin tuna catches. TOTAL CPUEW BY SET A ND TEMPERA TURE RETIONSHIP CPUEW/set Tª(º C) CPUEW (kg/ hooks) 9, 8, 7, 6,,, 3,,,, 3,1, 17/6,,6,3 4 6,1 6,3 6 6,8 6,1,3,8,9 6, ,33 666,67 16,67 3, 74, 8,33 8, 9, 7,93 86,8,6 64,,6 13, 1, /6 4/6 6/6 1/7 19/7 /7 1/7 /7 3/7 4/7 /7 6/7 7/7 8/7 9/7 Set date 3 1 Tª(º C) Tª may 17-may -may 3-may 6-may 9-may 4-jun 7-jun 1-jun 13-jun 16-jun 19-jun -jun -jun 8-jun Date Sea surface temperature in the Libyan traps 1-jul 4-jul 3 Number TOTAL CPUEN BY SET AND TEMPERATURE RELATIONSHIP CPUEN/set Tª(ºC) CPUEN(nº/ hooks) 14, 1, 1, 8, 6, 4,,, 3,1,83 17/6, 3,33 /6,6,83 4/6,3, 6/6 4, 1/7 6,1 6,3 6 6,8 1,6 1, 1, 1, 19/7 /7 1/7 /7 6,1,3,8 1, 9,4 3, 3/7 4/7 /7,9 8, 6/7 6,1 6 6,6,, 7/7 8/7 9/7 3 1 Tª(º C) W E Otros/Variable Set date Barbate Conil Bluefin tuna catches and temperature relationship in the Balearic Sea (from to -7-99) Percentage of bluefin tuna caught by traps atlatic in relation to factor wind (1986-).

19 ACTIVITIES Statistical activities and sampling. Collection of catch and effort data for species / gear. (Task I and II ICCAT). Biological sampling program in ports and on board. COPEMED working groups on: Standarization of metthods (CGPM-ICCAT). Growth: analysis of dorsal spines for age determination Reproduction: histological anaysis of gonads of bluefin tuna and swordfish. Abundance indices: utilizing GLM. Course stock study following ICCAT methodology. Stock structure: electronic tagging activity in collaboration with FAIR-UE Proyect. Presentation of Result: anual Reports of Activities and Results FAO-COPEMED Project Large Pelagics. Final Report Subprogram Gibraltar Elaboration of Scientific Documents COPEMED presented of SCRS de ICCAT during the period

20 Project FAO-COPEMED Large Pelagics Xiphias glaudius (Linnaeus,178) COORDINATOR J.M DE LA SERNA (IEO - SPAIN) PARTICIPANTS M. TAWIL (MBRC-LIBYA), A. FENECH F. (MCFS-MALTA), A.SROUR (INRH-MAROCCO), HATTOUR (INSTM-TUNISIA), J.M DE LA SERNA (IEO - SPAIN) PUBLISHER P. RIOJA (FAO -COPEMED)