PLANNING GROUP ON TUNA TAGGING. Report of the THIRD MEETING OF THE PLANNING GROUP ON TUNA TAGGING IN THE ATLANTIC AND MEDITERRANEAN SEA

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1 PLANNING GROUP ON TUNA TAGGING Report of the THIRD MEETING OF THE PLANNING GROUP ON TUNA TAGGING IN THE ATLANTIC AND MEDITERRANEAN SEA Heraklion, Crete, Greece 23-25th January 2007 TABLE OF CONTENTS OPENING AND ARRANGEMENTS... 2 ADOPTION OF THE AGENDA... 2 SESSION A: TAGGING SURVEYS IN Electronic Tagging Surveys for Bluefin Tuna in the Mediterranean Sea and eastern Atlantic Ocean Tuna tagging activities of Cyprus in IEO bluefin tuna electronic tagging activities during Preliminary results and applications Electronic tagging of bluefin in the Bay of Biscay... 3 Portuguese tagging activities in French tagging activities in Bluefin tuna (Thunnus thynnus) conventional tagging carried out by Spain in 2005 and Results and analysis including previous tagging activities... 4 Spanish bluefin conventional tagging campaign in Opportunistic tagging in the Bay of Biscay onboard sport fishing vessels... 5 Spanish swordfish conventional tagging Italian swordfish tagging campaigns Greek large pelagic tagging campaign in Summary and Discussion... 7 SESSION B: SUMMARY RESULTS OF PAST TAGGING ACTIVITIES CONTRIBUTION IN ASSESSMENT STUDIES... 7 Post-Processing Wildlife PSAT data from the European Tuna Tagging Program... 7 Habitat-based cpue standardization using electronic tagging data for juvenile bluefin tuna... 8 Utility of conventional tagging data for stock assessment... 8 Review of conventional swordfish tagging operations and the information provided... 9 Discussion SESSION C: FUTURE OF THE TUNA TAGGING SURVEYS IN THE FRAME OF THE DATA COLLECTION PROGRAMME SESSION D: OTHER MATTERS SESSION E: MEETING REPORT APPENDIX 1: LIST OF PARTICIPANTS APPENDIX 2: TERMS OF REFERENCE AND MEETING AGENDA APPENDIX 3: JOINT EUROPEAN TUNA TAGGING PROGRAM FOR st Meeting

2 - 2 - OPENING AND ARRANGEMENTS The in the East Atlantic and Mediterranean Sea held its third meeting in Heraklion, Crete (Greece) from 23rd to 25th January The meeting was attended by 14 scientists from 6 EU member states. The list of participants is given in Appendix 1 to this report. G. Tserpes was appointed as chairman of the meeting. J.M Fromentin and H. Arrizabalaga were appointed as rapporteur. ADOPTION OF THE AGENDA The Agenda attached as Appendix 2 to this report was adopted. SESSION A: TAGGING SURVEYS IN 2006 Summaries of the presentations describing the tagging activities carried out in 2006 are given below. In addition results of past tagging activities not presented in the previous meetings are also presented. Electronic Tagging Surveys for Bluefin Tuna in the Mediterranean Sea and eastern Atlantic Ocean. G. De Metrio, M. Deflorio Department of Animal Health and Well-being, University of Bari. According to the tagging plan established during the second meeting of the Planning Group on Tuna Tagging, held in Sliema, Malta 27-29th March 2006, Italian team had to tag 40 fish in the Mediterranean Sea and eastern Atlantic in That because the President of the Turkish Tuna Farmer Association, Mr Nedim Anbar, promised to donate 30 bluefin tuna for tagging purposes. In addition, it was forecasted that the remaining fish would be provided by a tuna farm belonging to the tuna-farm company Dardanel (Turkey) and by the other teams (Portuguese, Maltese and Spanish teams) involved in the European Tagging Program. Unfortunately, due to the relative poor fishing season in 2006, the fish available to be tagged were less than the ones predicted and therefore Italy deployed 33 pop-up archival satellite tags. As for these tags, 15 fish (52-78 kg) were donated by Turkish Tuna Farmer Association and released in Turkish waters between Turkey and Cyprus; 4 fish ( kg) were provided by the Portuguese team and released in eastern Atlantic; 2 fish (55 and 68 kg) were provided by the Spanish team and released in the western Mediterranean; 8 fish ( kg) were donated by the tuna farm located in Sicily (joint venture between the Spanish Fuentes Group and a local enterprise) and release in the south Tyrrhenian Sea; 4 fish (49-89 kg) were donated by the Cypriot team and released in the south Cypriot waters. Tuna tagging activities of Cyprus in 2006 V. Papadopoulos Following 2005 tagging operations where 10 fish were tagged in cooperation with the Italian team, in 2006 another 10 fish were tagged in Cyprus. This was also in line with the outcome and the planning that was decided on the Second Meeting of the in the Atlantic and Mediterranean Sea that was held in Malta on the th of March The tagging operations in Cyprus took place on the 20 th of November, Ten fish were kept in the cages of a fish faming unit and were tagged with 10 electronic satellite pop-up tags along with the help of the Italian team and then were released in the open sea south of Cyprus. ICCAT conventional spaghetti tags were also fitted in every one of the ten electronic tags that were used (double tagging). Five of the tags were programmed to pop up on the 1 st of May 2007 and the other five to pop up on the 21 st of May, Weight of the tagged fish ranged from 70 to 250 kg. Two of the electronic tags were detached prematurely and started to transmit within one week of the tagging date indicating that mortality may occurred in two of the tagged fish most probably due to the stress of the handling procedure during the tagging operations. Another four tags were prematurely

3 - 3 - detached, one on the 26 th of December, 2006 and the other three on the 6 th, 14 th and 18 th of January, 2007 and started to transmit. The four fish that carried the tags were 36, 47, 55 and 60 days at liberty, respectively. The data of these four tags are still in the process of being analyzed. In order to be able to make any assumptions regarding the reasons for these premature detachments, which present a problem in the collection and recording of valuable data, the already recorded and recovered (transmitted) data must be thoroughly analyzed. There are still another four tags that are expected to pop up in the near future. IEO bluefin tuna electronic tagging activities during Preliminary results and applications. Francisco J. Abascal and José M. de la Serna Due to administrative problems recently solved (through ICCAT participation in the purchase process) there has been a delay in the availability of the tags. In the case of the pop-up tags planned for 2005, they have finally been deployed during 2006 season. In August 2006, a total of 22 adult BFT, weighing between 45 and 230 kg (mean 86 kg) were tagged in Viver Atún facilities (Ricardo Fuentes Group), off southeastern Spain. These fishes had been caught by purse seine off Balearic Islands during the reproductive season, i.e. June-July, and kept in captivity in the farming facilities. The tagging was organized by Antonio Belmonte, from the farming company, coordinated by José Miguel de la Serna (IEO) and in collaboration with Dr. Michele Deflorio and Prof. Gregorio Demetrio (University of Bari). Up to date, we have received information from 11 tags. Additionally, 2 fish were recaptured. One of them by longline and the other by handline and close to the farming facilities off southeastern Spain where the fish were tagged. Due to the recent transmission of most of the tags, the information is still being processed. However, CLS has provided the preliminary tracks of the fish, as well as the time-at-depth and time-at-temperature histograms recorded by these tags. The results from these tags will be used for the calibration of longline indices. The percentage of time tuna spend at the same depth as the longline gear and its temporal variation can be used for the estimation of effective fishing effort and, consequently, for the calibration of CPUE series, taking into account the variations in catchability. A practical example is given. In the future, the relationship between oceanographic conditions and bluefin tuna habitat preferences will be used as input for the calibration of abundance indices. Regarding the trap abundance indices, information will be available by the end of May 2007, when the rest of the tags are programmed to pop-up. Regarding the difficulties in acquiring the 20 tags planned to be deployed in 2006, the purchase could be accomplished by the end of the year. It was agreed that tagging by that time of the year could seriously affect the behaviour of the fish because they were kept in captivity for several months and far from their natural habitat. Consequently, these tags will be deployed together with the 10 tags foreseen for 2007 during next fishing season. Electronic tagging of bluefin in the Bay of Biscay H. Arrizabalaga, AZTI During the 2006 season it was expected to rent a boat for one month for the sonic tracking experiment. Due to the low abundance of bluefin tuna in the Bay of Biscay (one of the worst seasons in the latest years), it was necessary to made arrangements to have the boat available for three months, expecting that bluefin would be available to trolling gear near the coast. In spite of this, only one bluefin was caught and tracked for 2 hours. Additional efforts to overcome this problem included implating some archival tags on juveniles. In total, 11 archival tags were implanted (5 in the Bay of Biscay and 6 in a trap in the Algarve thanks to the collaboration of IPIMAR). There was also a recovery of one of the two archival tags implanted in 2005, with 9 months of information on depth, internal and external temperature and position. This is the first recovery for a juvenile in the Bay of Biscay area and shows the path followed between consecutive migrations to the feeding area.

4 - 4 - Portuguese tagging activities in 2006 M. Neves dos Santos- IPIMAR/CRIPSul During 2006 IPIMAR established an agreement with a local tuna trap (TUNIPEX) located off Algarve (Southern Portugal), in order to tag BFT specimens and to use their trap facilities (boat, crane, etc) to carry out tuna tagging. In late July, IPIMAR tagged 8 adult BFT specimens with pop-up tags, which ranged in size between 121 and 195 cm and in weight between 49 and 153 kg. These were programmed to pop-off in late April One out of the 8 tags detached prematurely. IPIMAR also cooperated with UNIBARI tagging 4 adult BFT specimens with pop-up in late July, and with AZTI on tagging 5 juveniles BFT with internal archival tags in early November. All these cooperative activities took place in the TUNIPEX s tuna trap. No opportunistic conventional tagging on juveniles was carried out due to lack of fish during the tagging season (July/August). As regards to swordfish some opportunistic conventional tagging was carried out by observers within the national data collection program for this species. Due to the bad condition of the fish at the moment of gear retrieval, only 2 juveniles were tagged in the equatorial area in August French tagging activities in 2006 J. M. Fromentin - IFREMER France planned 8 pop-up archival tags medium size bluefin tuna from the sport fishery in Corsica. Tagging from sport fishing in Corsica gave excellent results in 2000 and 2001, but this fishery finally closed in 2006, since no bluefin tuna was caught since Therefore, the tagging season took place in Palamos (Spain) during one week, to take advantage of an important international sport tournament, targeting bluefin tuna. Not a single bluefin tuna was unfortunately caught (nor detected) in 2006 for the first time in the history of this tournament, so that we could not deploy our tags in To take into account for this recent lack of availability through artisanal or sport fishing (see below), the tags will be deployed in 2007 in an opportunistic manner until the summer with sport fishing and/or in farms in early Autumn. Bluefin tuna (Thunnus thynnus) conventional tagging carried out by Spain in 2005 and Results and analysis including previous tagging activities. E. Rodriguez-Marin - IEO This presentation described conventional tagging carried out by Spain in the Mediterranean and the Bay of Biscay in 2005 and Tagging activities were performed on board professional bait boat fishing vessels and throughout opportunistic tagging on board commercial and recreational vessels. A total of 1834 and 380 bluefin tuna were tagged in 2005 and 2006, respectively, representing a 15 % of the total tagged bluefin since 1977 in both areas by Spain. In the Mediterranean the bluefin tuna tagged were individuals aged 1 year or less, meanwhile in the Bay of Biscay most individuals tagged were 1 or 2 years old. The recaptured fish in 2005 were 80 and 19 in This presentation also summarizes the utility of this and previous conventional tagging data for obtaining information for the assessment of the population. Relative recapture rates based on tagged individuals and 702 recaptures show a close relationship between the west Mediterranean and the Bay of Biscay. More than 60% of the 0 and 1 year old specimens tagged in Balearic Island and Alboran Sea area have been recaptured in the Bay of Biscay with more than 1 year at liberty. Thus, indicating that the relative abundance index of juveniles in the Bay of Biscay can be representative of the western bluefin tuna population. No relationship was found between fishing activity and recaptures in the Bay of Biscay, but a relationship was seen between numbers of fish tagged and recaptures of fish tagged in the same year. Mean displacements of fish tagged and recaptured in the Bay of Biscay during the same tagging season, showed that probably fish remain inside this feeding area during the fishing season. Conventional tagging data were also used to obtain migration rates between the Mediterranean and the East Atlantic, growth parameters and mortality.

5 - 5 - Spanish bluefin conventional tagging campaign in 2006 E. Rodriguez-Marin - IEO Bluefin tuna conventional tagging in 2006 was less than scheduled due to low occurrence of juveniles and to their availability restricted to the beginning and ending of the fishing season. A total of 48 tunas were tagged in the Bay of Biscay in 2006, most of which were over 4 years old and were an average of 155 cm straight fork length and 70 kg in weight. The estimated length of the largest specimen tagged was 218 cm, which correspond to a fish of 11 years old. In the Mediterranean, 380 bluefin tuna were tagged in the Balearic Islands and Alboran Sea area. Lengths range between 37 and 125 cm FL, with a mean of 65 cm, thus, most of this tagged specimens were 1 year old. During the 2006, a total of 19 recaptures of bluefin tuna were reported. One had been tagged in the Strait of Gibraltar in November 2004 and had been recovered 19 months later in the Bay of Biscay. It measured 66 cm at tagging and had increased by 27 cm. Eleven of the recaptures were specimens tagged in the previous tagging season, thus most of them had been at liberty for nearly one year, whereas only three of the recaptures corresponded to the same tagging survey. A trawler caught one specimen the following day. The distance covered by this fish in one day was 48 miles in a NW direction. Opportunistic tagging in the Bay of Biscay onboard sport fishing vessels H. Arrizabalaga, AZTI Since 2001, AZTI-Tecnalia has conducted opportunistic tagging activities onboard sport fishing vessels operating in the Bay of Biscay. The activities imply assessing fishermen on tagging methods and promoting tag and release activities within tournaments and during regular fishing trips. In the last six years, the number of fish tagged using this platform has increased exponentially, with 2531 tunas tagged in 2006 (mainly albacore and bluefin, table 1). nº fish tagged ALB BFT Auxis sp. SKJ Total Total So far, 34 (1.13%) al bacore and 28 (13.08%) bluefin tuna have been recovered. The recovery rate in the case of bluefin tuna is surprisingly high. All data has been submitted to ICCAT to contribute to the global tagging database. Spanish swordfish conventional tagging 2006 J.M. de la Serna, S. Garcia Barcelona, J.M. Ortiz de Urbina - IEO In year 2006, the Spanish Institute of Oceanography carried out the swordfish tagging activities in the Mediterranean scheduled by the European Tuna Tagging Programme. Three longline vessels were involved on these activities. Two longliners were contracted in order to develop tagging activities following the technical and strategical protocol scheduled by the IEO, making use of an experimental gear with several types of hooks and baits. Regarding the third vessel, observers on board carried out opportunistic swordfish tagging during its normal fishing activity. A total of 260 swordfish, ranging from 45 cm to 124 cm length (LJFL), were tagged with conventional tags. Making use of several types of hooks, including circular ones, made possible that 79% of the tagged swordfish were hooked in the mouth, which is supposed to favour survival.

6 - 6 - Italian swordfish tagging campaigns L. Orsi Relini, G. Palandri, F. Garibaldi, M. Relini - Laboratory of Marine Biology and Animal Ecology - Dip. Te. Ris. University of Genoa Conventional tagging of 150 individuals of swordfish per year, from 2005 onward, in the Central Mediterranean, was planned by the P.G.T.T. during the session 2005 and Such activities were funded by the EC to the Italian MiPAAF, which assigned the project to the Società Italiana di Biologia Marina with the coordination of our team. Field activities started in autumn The tagging work was divided in 5 equal parts, with 5 O.U. in the different Italian seas concerned by the swordfish fishery: Ligurian (resp. L. Orsi), Tyrrhenian (resp. A. Di Natale), South Adriatic (resp. G. Marano), Ionian Seas (resp. G. De Metrio) and waters of Western Sardinia (resp. A. Cau). The reason of this allocation of tagging was that sometime genetic studies on large pelagic fish show different population units along Eastern and Western side of the Italian Peninsula, so that possible different migratory performances are envisaged. A second reason was that distances covered by tagged fish are known to be important, so also information concerning tagging should be as large as possible, and this target is more easily obtained with more teams working in different areas. During autumn 2005 a total of 32 swordfish were tagged, 25 in the Tyrrhenian, 5 in the Ionian and 2 in the Sardinian Seas; during 2006, a total of 246: 32 in the Ligurian, 35 in the Tyrrhenian, 2 in Sardinian, 161 in the Ionian and 16 in the Adriatic Seas. As far as our study area, the Ligurian Sea, is concerned, we recall other two interesting point regarding swordfish tagging: 1) after the release, in Autumn 1994 of a lot of 32 young specimens, one of them was recaptured three years later, few miles apart the tagging point (Gariba ldi et al., 1999). Similar results at present are considered possibly linked to a homing behaviour of the fish (Sedberry and Loefer, 2001; Takahashi et al., 2003). 2) The first attempt to tag swordfish by electronic devices started in 2003, with a PhD thesis, carried out in our Department (Canese et al., 2004). From 2004 a national project was funded by MiPAAF: it concerned both young and adult fish, obtained by longlines and by harpoon respectively: the former were tracked in our area and the latter in the Messina Strait (ICRAM and Istituto Talassografico di Messina). The results of the electronic tagging of about 20 specimens will be presented in the next ad hoc ICCAT meeting. Greek large pelagic tagging campaign in 2006 P. Peristeraki, HCMR The aim of the project was to realise tagging on juvenile swordfish in the eastern Mediterranean. Tagging operations were carried out from October to December 2006 in the Aegean Sea. Eight commercial boats were employed for the tagging operation. Small drifting long-lines were used for the fish capture. Those of the captured animals that were in good condition were measured on the deck of the boat, tagged and released to the sea. Date, time and geographical co-ordinates of the capture location were recorded. Forty three days of fishing were totally realised for the swordfish tagging campaign and 158 juvenile swordfish were tagged by spaghetti-type conventional tags provided by ICCAT. Nine juvenile bluefin tunas that were also captured were tagged and released to the sea. In order to maximise the chances to get back data on the recaptures, the advertising campaign to fishers and harbour authorities was continued, through posters, T-shirts, circulars etc. Moreover, every reported recapture is awarded. The Greek tagging campaign was accomplished according to the plan agreed during the coordination tagging meeting held in Malta (27-29/3/2006). Tagging and recapture details are officially reported to ICCAT.

7 - 7 - Summary and Discussion Bluefin Tuna During the 2006 season, 71 bluefin tuna were tagged with pop-up archival tags (PSAT), 1 with acoustic tag and 380 with conventional tags. The deployment of PSAT was thus better than during the 2005 season, but the objective of 105 deployments was not fully achieved. The success of the conventional tagging season was lower than in In all cases (PSAT, acoustic and conventional tags), all the planned cruises have been done, but were less successful than expected due to the poor availability of fish. Most of the artisanal fleets, e.g., sport, trap and bait boat, had indeed faced low catch rates in The baitboat catch in 2006 was about ¼ of that of 2005, while sport fishing in France did not catch a single large bluefin tuna for the first time in its history. Conclusively, the very bad catches have strongly affected several tagging operations in 2006 (especially conventional and acoustic tagging). No information has been provided about the 2006 tagging survey of Malta and Ireland. Among the 71 PSAT deployed, 3 bluefin were recaptured and 33 detached prematurely (the remaining is expected to pop-off in spring 2007). The group made a preliminary analysis of the reasons of these predetachments. The first cause seems to be related to technical problems that could be due to the attachment procedure or the tag itself. Secondly, pre-detachment relates to the death of the fish after tagging, due to the stress of the manipulation or to infection. The group decided to perform a full analysis of these problems that might be presented to tag manufacturers and non-europeans tagging experts during the second international symposium on Tracking and Tagging of Marine Fish with Electronic Devices to be held in San Sebastian in October 2007 ( Whatsoever, the information provided by the pre-detached PSAT gave interesting indications about migration patterns, mixing rates and habitat preferences that could be of use for tuning CPUE rates (see below). In addition, 11 archival tags have been deployed by AZTI on juvenile bluefin tuna in One tag was recovered after 9 months at liberty, providing useful information for tuning the CPUE of bait boat in the Bay of Biscay (see below). Swordfish During the 2006 season, 664 swordfish (158 by Greece, 246 by Italy and 260 by Spain) have been tagged in the Mediterranean using conventional tags, so that the objectives (450 tags) were more than achieved and the whole survey was considered to be very successful. At the date of the meeting, no recapture has been reported yet. In addition, Italy has reported the deployment of 9 PSAT on swordfish in 2006 in the Mediterranean Sea. This project was not part of the data collection program, but it is of great interest as very few attempts to tag swordfish with electronic tags have been performed so far. SESSION B: SUMMARY RESULTS OF PAST TAGGING ACTIVITIES CONTRIBUTION IN ASSESSMENT STUDIES. Summaries of the presentations are provided below. Post-Processing Wildlife PSAT data from the European Tuna Tagging Program Jean Marc Fromentin, IFREMER In 2006, the European Tuna Tagging Program (ETTP) funded by the data collection decided to post - process all the tracking data in a homogeneous way and using the most advanced technique. This has been done through a contract with CLS-Argos which provided the following services:

8 - 8 - ARGOS location and data collection for the whole period during which the pop-up tag is effectively active. This includes real-time delivery of positions files (DIAG by ) to monitor tag surfacing Decryption of the tag data: depth, temperature and light-level data. For Wildlife Computer (WC) tags we apply the WC-AMP software to the Argos DS files Light level based underwater positioning. For WC tags, the longitude is automatically estimated using the WC-GPE software and the latitude is estimated using software developed by CLS Underwater track re-estimation using an ensemble Kalman filter constrained by a simple movement model + the light-derived positions + satellite-derived surface temperature + bathymetry (e.g. Royer et al., 2005; Royer et al. 2007) Provision of raw and processed data (online + CD copy upon request). The Kalman filter constrained by temperature and bathymetry was presented to the group in more details and discussed. There are still a few technical points to improve, especially in relation to the fit of the light data, but the first results obtained on 10 PSAT are very satisfactory and give reliable information about time of residency and mixing rates. Habitat-based cpue standardization using electronic tagging data for juvenile bluefin tuna I. Arregi, H. Arrizabalaga, N. Goñi, S. Sanchez, D. Garcia, S. Guinehut An example of the use of electronic tagging data in habitat based models for cpue standardization was shown. Daily logbook catch at age data ( ), provided by IEO and AZTI, were used for this purpose. Hidrographic data (temperature at depth for every 1/3 of degree and week) was obtained from Mercator s ARMOR-3D product (Larnicol et al. 2006), and gear configuration (probability of catching at different depths) was obtained from surveys to skippers. Data on habitat use was obtained by combining 4 sonic tracks (2-5 hours) and 1 archival tag (9 months). The results show that the gear and the habitat do not overlap completely, so catchability is affected by the habitat distribution. However, the nominal cpue and habitat based cpue (as well as the GLMM standardized cpue) did not show significant interannual differences. These results are preliminary, and whether the lack of difference is due to the relatively smoothed hydrographic data used needs further checking, as the weekly data are moving averages that take into account data from previous and posterior weeks. Future electronic tagging results are also believed to improve confidence in the habitat knowledge data used in this example. References Larnicol, G., S. Guinehut, M.-H. Rio, M. Drevillon, Y. Faugere and G. Nicolas, 2006: The Global Observed Ocean Products of the French Mercator project, Proceedings of 15 Years of progress in Radar Altimetry Symposium, ESA Special Publication, SP-614. Utility of conventional tagging data for stock assessment. E. Rodriguez-Marin - IEO Historical conventional tagging data base, obtained mainly by the Spanish Institute o Oceanography throughout series of tagging surveys in the Bay of Biscay and the Mediterranean since 1977, together with conventional tagging data funded by the European Data Collection Program has allowed to estimate parameters useful for stock assessment. For this study tagged fish and 702 recaptures reported to date have been considered. The activities funded by the Data collection program represent 15 % of the total number of specimens tagged. Relative recapture rates based on these data show a close relationship between the west Mediterranean and the Bay of Biscay. More than 60% of the 0 and 1 year old specimens tagged in Balearic Island and Alboran Sea area have been recaptured in the Bay of Biscay with at least one year at liberty. Thus, indicating that the relative abundance index of juveniles in the Bay of Biscay can be representative of the western bluefin tuna population. No relationship was found between fishing activity

9 - 9 - and recaptures in the Bay of Biscay, but a relationship was seen between numbers of fish tagged and recaptures of fish tagged in the same year. Mean displacements of fish tagged and recaptured in the Bay of Biscay during the same tagging season, showed that probably fish remain inside this feeding area during the fishing season. Conventional tagging data were also used to obtain migration rates between the Mediterranean and the East Atlantic and to assess the optimum number of fish that would need to be tagged to estimate migration rates with precision (Arregi et a., 2006). Data set was fit under different model structures (fishing mortality, reporting rates, and migration in the same year of tagging). Results show that transatlantic migration rate estimates were similar to previous studies: 0.4%-4.9% from East to West and 2.9%-11.8% from West to East. Migration rates between the East Atlantic and the Mediterranean ranged considerably depending on model definition and reporting rate assumptions. Under most of the proposed scenarios, practically no gain in precision and accuracy occurred when tagging more than 10,000-15,000 fish. Estimation of growth parameters from tagging data was also achieved (Rodríguez -Cabello et al., 2006). The data set, which included recaptures after more than six months at liberty (n=179) was selected after exploring the residuals in order to eliminate the possible effect tagging might have on short-term growth and to minimize the possible effects of seasonal fluctuations in growth on parameter estimation. The estimates of the growth parameters in this study are rather imprecise, perhaps as a result of various sources of uncertainty such as small sample size, inaccurate size measurements at the time of tagging and/or recapture, preponderance of short times at liberty, the potential effects of tagging on growth, etc. Nevertheless, the tagging data used appear to be consistent with the currently-adopted growth curve for the stock. Estimation of mortality from tagging data was accomplished (Rodríguez-Marín et al., 2005). Four different models were compared, considering survival (S) and recovery rate (f) constant or time-specific for the Bay of Biscay and the Mediterranean Sea. The results indicate that there is evidence of variability in survival and recapture rates among years in both areas. The recovery rates are low in both areas but particularly those of the Mediterranean Sea. The estimated survival rate obtained by the more simple model with constant S, gave S= and S= for the Bay of Biscay and Mediterranean respectively. Thus, the finite mortality rate would be Z=0.51 and Z= 0.70 respectively. Though many factors could help to explain this difference, one possible explanation is a distinct survival rate between age groups. Whereas in the first area most of the fish tagged correspond to groups of age 1 and 2 in the Mediterranean Sea, all the fish tagged correspond to 0 and 1 year old. References Arregui, I., H. Arrizabalaga, J.M. De la Serna Preliminary approach to the experimental design of tagging campaigns for movement rates estimation of East Atlantic bluefin tuna. Col. Vol. Sci. Pap. ICCAT 59 (3) Rodríguez-Cabello C., V. R. Restrepo, E. Rodríguez-Marín 1, J.L.Cort and J. M. De la Serna Estimation of North East Atlantic Bluefin Tuna ( Thunnus thynnus) Growth Parameters from Tagging Data. ICCAT SCRS/06/096. Rodríguez-Marín, E., C. Rodríguez-Cabello, J.M. De la Serna, J.L. Cort, E. Alot, J.C. Rey, V. Ortiz de Zarate, J.L. Gutierrez and E. Abad A Review of Bluefin Tuna Juveniles Tagging Information and Mortality Estimation in Waters around the Iberian Peninsula. Collective Volume of Scientific Papers, ICCAT, 58(4): Review of conventional swordfish tagging operations and the information provided George Tserpes, HCMR Based on information derived, both from the ICCAT database and previous works, the presentation summarized the results of past tagging operations for swordfish carried out in the Atlantic and the Mediterranean. In the Atlantic, tagging operations started in early 60 s and so far more than fish have been tagged. Reported recapture rates are up to 5%. In the Mediterranean tagging operations started in

10 early 90 s and are more intensive in the latest years. Up to now (including the 2006 tagging operations) it is estimated that around to 1000 individuals have been tagged. Reported recapture rates are much lower than those of the Atlantic. To a large extent, results of the tagging operations support the swordfish stock structure assumed by ICCAT for the Atlantic-Mediterranean area. In addition, they have provided information suggesting the existence of high individual growth rate variability in the Atlantic. Discussion In general, the presentations in this session showed the use of conventional tagging experiments to study stock structure and estimate parameters such as growth, mortality and migration rates. Among the problems associated with conventional tagging experiments, the following were identified: - Low recovery rates in the Mediterranean area, likely due to unreporting. - Minimum size regulations affect recovery rates, especially for bluefin tuna. - Non optimum experimental design of past tagging activities aiming to estimate mixing and mortality rates - Decreasing availabity of bluefin tuna to the artisanal fisheries in the latest years. Regarding electronic tagging there have been important advances. The fact that the post-processing of popup tagging data has been centralized assures a standardized outcome from the experiments carried out in different countries. This permits a joint analysis of the tags, allowing to improve knowledge on species habitat, residency time and mixing rates between areas. Preliminary results from tags processed in 2006 indicated that most of the fish would remain in the area of tagging. Results from electronic tagging on juvenile fish have been already used in a preliminary way within a habitat based CPUE standardization from baitboat fisheries, and results from pop-up tags in adults could be used for the calibration of other fisheries, SESSION C: FUTURE OF THE TUNA TAGGING SURVEYS IN THE FRAME OF THE DATA COLLECTION PROGRAMME. Because tuna and tuna-like species are highly migratory species, distributed over large areas (such as the whole North Atlantic), there is no possibility to conduct traditional scientific surveys, such as the acoustic or trawling surveys that are routinely carried out for small pelagic and/or demersal fish. Consequently, stock assessments of tuna and tuna-like species depend mostly, and in many cases only, on fisheries information (i.e., catch and effort). The major source of scientific information for tuna could be, however, provided by tagging. Tagging has indeed significantly contributed to the assessment of certain tuna stocks for which large-scale tagging programs have been accomplished. In these cases, tagging is comparable to the scientific surveys, as it has allowed the estimation of biological parameters, such as growth, mixing rates, natural mortality, exploitation rates and interactions between fisheries. More recently, integrated statistical models, such as MULTIFAN CL, have been developed to assess tuna stocks. These models that appear to be the most satisfactory ones, integrate catch, effort, size and tagging data (which thus become a source of information as important as catch and CPUE). However, tagging information remains too rarely used for many tuna stocks because the quantity and/or quality of tagging data is often insufficient. Furthermore, electronic tagging gives information on the behaviour and habitat use of the fish (depth and temperature preferences, fishery independent migration routes, feeding, etc) and their associations with other fishes or FADs (e.g. time of residence). Electronic tagging has been also used to assess mixing rates between stocks, independently of fishery dynamics (e.g., Atlantic bluefin tuna) and the availability of the stock to a given gear/fishery.

11 Ocean-wide massive tagging is the most beneficial in the medium term and is encouraged by the scientific bodies of all regional tuna fisheries organizations (e,g. ICCAT and IOTC). These programmes are expensive, but remain relatively cheap in comparison to the scientific surveys ( the cost of the tagging operation of each national entity is, within the 2005 and 2006 Data Collection Programs, lower than 10% of the costs of the trawling and acoustic surveys). So, we strongly recommend that a specific line on tuna tagging be maintained in the EU Data Collection Program to allow the collection of scientific information for tuna and tuna-like species. This specific line could allow the funding of extensive tagging surveys for a given tuna species over a specific period (e.g., 1 to 3 years). Although it is not necessary for such operations to be carried out on a routine basis, some continuity should be maintained (by repeating tagging survey from time to time). These tagging operations should tackle a precise scientific issue with clear objectives and sampling design. They should also be evaluated through a peer-review process. Regarding the tagging programme for 2007, minor modifications of the tentative plan established in Malta 2006, have been adopted and the new plan is presented on Appendix 3. Those modifications are: In the Bay of Biscay, the conventional tagging and sonic tracking surveys for bluefin tuna by Spain, were replaced by an archival tagging survey. Pop-up tagging of swordfish in the Azores area by Portugal has been removed, and consequently the number of bluefin pop-up tagging has increased off the southern Portugal area (Algarve). In the central Mediterranean a pop-up survey for swordfish by Italy has been foreseen, pending on possible national co-funding. Budget changes are shown in bold-underlined fonts. SESSION D: OTHER MATTERS The EU representative provided information on additional source of funding in support of data collection and research for tuna and tuna-like species. Those included workshops, coordinated meetings and small scale studies under the Data Collection Programme, as well as proposals to the EFARO organisation. The group was encouraged to propose projects to the next meetings: Regional Coordination Meeting for the Mediterranean waters (Cyprus, April, 2007) and the forthcoming EFARO meeting. The group agreed to have the 4 th meeting of the Coordinated Tuna Tagging Programme during the second half of 2008 in order to synthesize the results of the tagging operations carried out over (tentative place: Sète or Santander, contact person: J.M. Fromentin). SESSION E: MEETING REPORT The report was adopted during the meeting. The meeting was adjourned.

12 APPENDIX 1: LIST OF PARTICIPANTS Cyprus: - Vassilis Papadopoulos Fisheries and Marine Research Officer Department of Fisheries and marine Research Aelou Nicosia Cyprus Tel: Fax: vpapadopoulos@dfmr.moa.gov.cy France: - Jean Marc Fromentin IFREMER, Centre de Recherche Halieutique Mediterraneen et Tropical Avenue Jean Monet BP Sete cedex FRANCE Jean.Marc.Fromentin@ifremer.fr Greece: - George Tserpes Hellenic Center for Marine Research (HCMR) P.O. Box Iraklion, Greece Tel: Fax: gtserpes@her.hcmr.gr - Panagiota Peristeraki Hellenic Center for Marine Research (HCMR) P.O. Box Iraklion, Greece Tel: Fax: notap@her.hcmr.gr - George Lazarakis Hellenic Center for Marine Research (HCMR) P.O. Box Iraklion, Greece Tel: Fax: glazaros@her.hcmr.gr - Costas Skarvelis Hellenic Center for Marine Research (HCMR) P.O. Box Iraklion, Greece Tel: Fax: skarvelis@her.hcmr.gr

13 Italy: - Gregorio de Metrio Department of Animal Health and Well-being Faculty of Veterinary Medicine, University of Bari. Str. Prov. Casamassima km Valenzano (Bari) Tel: Fax: g.demetrio@veterinaria.uniba.it - Michele Deflorio Department of Animal Health and Well-being Faculty of Veterinary Medicine, University of Bari. Str. Prov. Casamassima km Valenzano (Bari) Tel: Fax: m.deflorio@veterinaria.uniba.it - Giovani Palandri Laboratory of Marine Biology and Animal Ecology Dip. Te. Ris. University of Genoa Corsa Europa Genoa Italy Tel: Fax: largepel@unige.it Portugal : - Miguel Neves dos Santos IPIMAR/CRIPSul Av. 5 de Outubro s/n Olhão Portugal Phone: Fax: mnsantos@cripsul.ipimar.pt Spain: - Haritz Arrizabalaga AZTI - Tecnalia /Marine Research Unit Herrera Kaia Portualdea z/g Pasaia (Gipuzkoa) Tel: Fax: harri@pas.azti.es - Francisco J. Abascal Insituto Español de Oceanografía Centro de Cádiz Centro Andaluz de Ciencia y Tecnología Marina (CACYTMAR) Av. República Saharaui s/n, Puerto Real (Cádiz), Spain Tel: francisco.abascal@uca.es

14 Josetsxu Ortiz de Urbina Instituto Español de Oceanografía Puerto Pesquero s/n Aptdo 285 Fuengirola Malaga, Spain Tel: Fax: urbina@ma.ieo.es - Enrique Rodriguez-Marin Instituto Español de Oceanografía Ministerio de Educacion y Ciencia P.O. Box Satander Spain Tel: Fax: rodriguez.marin@st.ieo.es EC: - Philippe Moguedet Directorate General Fisheries and Maritime Affairs Research, Data Collection and Scientific Advice Unit Rue Joseph II, 79 Brussels - Belgium Tel: Philippe.Moguedet@ec.europa.eu

15 APPENDIX 2: TERMS OF REFERENCE AND MEETING AGENDA TERMS OF REFERENCE ToR 1. Presentation of the tagging activities carried out in problems encountered. ToR 3. Review of tagging activities and their contribution in assessment studies. ToR 2. Future tagging plans OPENING AND ARRANGEMENTS ADOPTION OF THE AGENDA MEETING AGENDA SESSION A: TAGGING SURVEYS IN 2006 List of presentations Electronic Tagging Surveys for Bluefin Tuna in the Mediterranean Sea and eastern Atlantic Ocean. G. De Metrio, M. Deflorio Department of Animal Health and Well-being, University of Bari. Tuna tagging activities of Cyprus in 2006 V. Papadopoulos IEO bluefin tuna electronic tagging activities during Preliminary results and applications. Francisco J. Abascal and José M. de la Serna Electronic tagging of bluefin in the Bay of Biscay H. Arrizabalaga, AZTI Portuguese tagging activities in 2006 M. Neves dos Santos- IPIMAR/CRIPSul French tagging activities in 2006 J. M. Fromentin - IFREMER Bluefin tuna (Thunnus thynnus) conventional tagging carried out by Spain in 2005 and Results and analysis including previous tagging activities. E. Rodriguez-Marin IEO Spanish 2006 Bluefin conventional tagging results. E. Rodriguez-Marin IEO Opportunistic tagging in the Bay of Biscay onboard sport fishing vessels H. Arrizabalaga, AZTI Spanish swordfish conventional tagging 2006 J.M. de la Serna, S. Garcia Barcelona, J.M. Ortiz de Urbina - IEO Italian swordfish tagging campaigns L. Orsi Relini, G. Palandri, F. Garibaldi, M. Relini - Laboratory of Marine Biology and Animal Ecology - Dip. Te. Ris. University of Genoa

16 Greek large pelagic tagging campaign in 2006 P. Peristeraki, HCMR Discussion SESSION B: SUMMARY RESULTS OF PAST TAGGING ACTIVITIES CONTRIBUTION IN ASSESSMENT STUDIES. List of presentations Post-Processing Wildlife PSAT data from the European Tuna Tagging Program Jean Marc Fromentin, IFREMER Habitat-based CPUE standardization using electronic tagging data for juvenile bluefin tuna I. Arregi, H. Arrizabalaga, N. Goñi, S. Sanchez, D. Garcia, S. Guinehut Utility of conventional tagging data for stock assessment. E. Rodriguez-Marin - IEO Review of conventional swordfish tagging operations and of the information provided George Tserpes, HCMR Discussion SESSION C: FUTURE OF THE TUNA TAGGING SURVEYS IN THE FRAME OF THE DATA COLLECTION PROGRAMME. SESSION D: OTHER MATTERS SESSION E: MEETING REPORT

17 APPENDIX 3: JOINT EUROPEAN TUNA TAGGING PROGRAM FOR 2007 Bluefin tuna Table 1 BFT tagging programme 2007 (pop-up satellite and archival tags) Type of Fishing Objectives Fishing area Country Tagging place Gear tags period Tagging period Programmed time Expected pop-up date Number/size of fish Refine CPUE from Bait boat archival Bay of Biscay Jun-Sep Spain Bay of Biscay Baitboat Jul-Aug 2007 n=120 ; 10 kg - Refine CPUE from Tuna trap, Spanish, Italian and Japanese longline - Mixing rates pop-up satellite East Atlantic Apr-Aug Ireland Irish waters Sport fishing Sep days May 2008 n=5 ; 200 kg East Atlantic Apr-Aug Portugal Algarve Tuna trap Jul days April 2008 n=5 ; 150 kg West Med Apr-Aug Spain Cartagena Tuna pens Jul days April 2008 n=10 ; 100 kg Central Med Apr-Aug France Corsica Sport fishing Sep days May 2008 n=10 ; 80 kg Central Med Apr-Aug Malta Malta waters Tuna pens Jul days April 2008 n=5 ; 100 kg East Med Apr-Aug Italy East Med Purse seine Jun days April 2008 n=20 ; 100 kg East Med Apr-Aug Cyprus East Med Tuna pens Nov days May 2008 n=10 ; 100 kg Table 2 BFT tagging programme 2007 (conventional tags) Tagging Fishing area Country Tagging place Gear period Expected number/size of fish East Atlantic Jun-Sep Portugal Algarve Tuna Trap Opportunistic* Jun-Sep Spain Bay of Biscay *No budget is requested for opportunistic tagging Sport Fisheries Opportunistic*

18 Swordfish Table 3. Conventional tagging on swordfish Area Country Tagging period Expected number of tags to be released E. Mediterranean Greece Oct-Dec ~150 C. Mediterranean Italy Oct-Dec ~150 W. Mediterranean Spain Oct-Dec ~150 C. Atlantic Spain Jan-Dec ~200 N. Atlantic Portugal Jan-Dec Opportunistic* *No budget is requested for opportunistic tagging Table 4. Electronic pop up tagging on swordfish Area Period Country Gear Programmed time Expected popup date Number/size of fish Canaria Aug-Nov 2007 Spain Long-line 270 days Apr-Jul 2008 n=5 ; 50 kg Baleares Apr-Aug 2007 Spain Long-line 270 days C. Med* Aug-Dec 2007 Italy Long-line 270 days Dec Apr 2008 May2008 Sept 2008 n=5 ; 40 kg n=5; 30kg East Med Jul-Oct 2007 Greece Long-line 270 days Mar-Jun 2008 n=5 ; 40 kg *Accomplishment of the survey depends on budget availability.

19 TENTATIVE BUDGET OF THE 2007 TUNA TAGGING PROGRAMME* BFT tagging economic plan 2007 Country Tagging place Number Size of Total Euros per Total cost cost per each Total cost Total cost of personnel x Personnel and Boat ARGOS Type of tags of fish fish (kg) weight kilo of fish tag (Euro) of tags darts days travel costs* renting service Others TOTAL Ireland Irish waters pop-up satellite x Portugal Algarve pop-up satellite x Spain Cartagena pop-up satellite x France Corsica donated 0 pop-up satellite x Italy East Med pop-up satellite x Malta Malta waters pop-up satellite x Cyprus Levantine Sea pop-up satellite x Spain Cantabrico archival x TOTAL * This includes travelling costs to other countries for cooperation among participants Ireland and Portugal cost of tags bought and refurbished SWO electronic tagging economic plan 2007 Country Tagging place Number Size of Total Euros per Total cost cost per each Total cost Total cost of personnel x Personnel and Boat ARGOS Type of tags of fish fish (kg) weight kilo of fish tag (Euro) of tags darts days travel costs* renting service Others TOTAL Italy Central Med pop-up satellite X Greece East Med pop-up satellite Spain West Med pop-up satellite x Spain Atlantic pop-up satellite X TOTAL SWO conventional tagging economic plan 2007 Country Tagging place Number of fish Type of tags Personnel and travel costs Boat service Others TOTAL Portugal NE Atlantic opportunistic conventional tags - Spain Central Atlantic 200 conventional tags Spain West Med 150 conventional tags Italy Central Med 150 conventional tags Greece Est Med 150 conventional tags TOTAL TOTAL TAGGING PROGRAMME 2007 = * Changes with respect to the budget presented on Appendix 6 of the report of the 2 nd PGTT meeting (Malta, March, 2006) appear in bold-underlined fonts.