ICCAT-GBYP AERIAL SURVEY: OBJECTIVES AND APPROACH. Antonio Di Natale GBYP Coordinator ICCAT

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1 ICCAT-GBYP AERIAL SURVEY: OBJECTIVES AND APPROACH Antonio Di Natale GBYP Coordinator ICCAT GBYP Workshop on Aerial Surveys ICCAT, Madrid, June 4, 2013

2 General objectives SCRS, in 2008, listed the Aerial surveys as one of the tool to support development of fishery independent indices; SCRS, in 2009, included the development of fishery independent surveys as the highest priority and ICCAT officially endorsed the programme. The co-funded Atlantic-wide research programme for bluefin tuna (GBYP) identified the aerial survey as one of the three research activities in Phase 1. The GBYP Steering Committee, in 2010, decided to carry out the aerial survey only on spawning aggregations, as the best possible compromise between financial resources and research possibilities, inviting CPCs to possibly develop autonomous surveys on aggregations of juveniles. The GBYP Steering Committee, in 2012, decided to carry out the aerial survey for covering extensively the majority of the spawning areas in the Mediterranean Sea, providing that an acceptable CV will be ensured.

3 STRATEGY IN PHASE 1 & 2 1. Identify the areas where the spawning activity in recent years was probably more intense or constant. 2. Have a statistical-sound survey design, based on transects (Distant software). 3. Identify the most reliable companies to carry out the surveys. 4. Provide a constant monitoring and support for the activities. 5. Get an almost real-time analysis of the result. 6. Possibly correlate the results with oceanographic data. 7. Get the best value-for-money 8. Provide the first necessary steps to develop a credible index of the minimum bluefin tuna spawning biomass

4 STRATEGY IN PHASE 1 & 2 1. Statistically sound survey design (DISTANCE). 2. Use of high-wings 2-engines aircrafts. 3. Use of bubble windows (from Phase 2 on). 4. Use of declinometers (from Phase 2 on). 5. Spotting altitude of 300 m. 6. Constant speed of 100 knots. 7. Survey to be conducted only under suitable weather conditions: a) Winds lower then 3 or 4 Beaufort b) Absence of low clouds at less then 300 m altitude c) Absence of heavy rain d) Absence of fog

5 SPOTTING STRATEGY IN PHASE 1 & 2 COMMON FORMAT OF SIGHTING FILES What to recorder???? 1. Bluefin aggregations of spawners (mandatory) 2. Marine mammals (useful) 3. Sea Turtles (useful) 4. Bluefin tuna fishing vessels (without any name - useful)

6 ACTIONS IN PHASE 1 & 2 A. Identifications of all areas where the purse-seine fishing activities were more intense in the last 3 years, by using VMS data analysis, checking the results against the existing scientific knowledge. B. Selection (Call for Tenders) of a high-level professional for setting-up the GBYP Aerial Survey design, improving it after the comments by the Steering Committee. C. Selection (Call for Tenders) of high-qualified companies to carry-out the aerial survey on spawning aggregations in 2010, with precise instructions on the agreed methodology. D. Establish a real time monitoring, with constant contacts with the companies, providing support, scientific and operational assistance, along with the necessary diplomatic assistance to possibly get the necessary flight permits. This procedure allowed GBYP to adapt in emergency the survey design when flight permits were not released by some CPCs, preventing the survey in three important areas. E. Selection (Call for Tenders) of high-level specialist to provide the analysis of the data collected in 2010 and 2011, assisting all contractors to revise all data. F. Selection of a high-level company to provide a 10-year collection of SST data (0.25 x0.25 resolution), corrected with in situ data, for the period May-July. G. Selection (Call for Tenders) of high-level scientists to provide a first analysis correlating aerial survey data with oceanographic conditions. H. Present the results to SCRS 2010 and 2011 for the approval and to the ICCAT Commission meeting for the endorsement.

7 SURVEY TOOLS IN PHASE 1 and sub-areas instead of 3 (8 after the need to identify additional sub-areas) in Phase 1; 2. 3 sub-areas in Phase 2 3. A statistically-based aerial survey design made by Prof. Phil Hammond and Dr. Ana Cañadas 4. Standard protocols (constant altitude of 300 m; constant speed of 100 knots; pictures of all sightings; weather requirements of wind <3 Beaufort, clouds >300 m, not with heavy rain, good visibility, no fog, etc.) and standard reporting files companies (Grup AirMed, Périgord Travail Aérien and Unimar) carrying out the aerial surveys aircrafts (Partenavia P68 C in area 1, 2 and 3; Cessna 337 Skymaster N and Cessna 337 Skymaster N in areas 6, 7 and 8) in Phase 1; 4 aircrafts in Phase teams (6 pilots, 6 professional spotters and 6 scientific observers) in Phase 1 and 4 teams in Phase 2;. 8. Real time GPS Garmin interfaced with the GPS of the aircraft for a detailed mapping. 9. Daily monitoring of SST and wind in all the Mediterranean, with library record of printed maps. 10. A strong support at the ICCAT Secretariat.

8 TOOLS IN PHASE

9 LIMITS IN PHASE 1 No flight permits were made available in Tunisian (W area 3), Libyan (S sub-area 3 and full sub-area 4) and Egyptian (full sub-area 5) areas. The new additional sub-areas (7 and 8) had lower potential concentration of spawners and were adopted only in the last week of June. The SST temperature was abnormally colder than the average in the second part of May and June in the NW and N central Mediterranean, preventing the right conditions for spawning. The winds were abnormally strong for many days and in most of the basin, reducing the stabilisation of the thermocline and preventing the aerial surveys in many areas and in too many days. Temperature (green if >21 C)

10 TOOLS IN PHASE

11 LIMITS IN PHASE 2 No flight permits were made available in Libyan area (S sub-area 3). The permit for area 4 (Turkey) arrived after the spawning period; Syria never provided a permit. 31.8% of the potential spawning period was not favourable for aerial spotting, due to notsuitable conditions; May was particularly cold and with a lot of wind, particularly in the central Mediterranean, where the thermocline was established later in the season. The average of non-suitable days during the survey was around 22%. A large area with warm water was present between Cirenaica and the central Ionian Sea; it seems that many spawning aggregations in late May were heading there. Temperature (green if >21 C) surface temperature C 2011 MAY JUNE JULIO area Balearic Sea South Tyrrhenian 2 Sea 3CM - Strait of 3 Sicily East 6 Mediterranean sea state 2011 MAY JUNE JULIO area Balearic Sea South Tyrrhenian 2 Sea 3CM - Strait of 3 Sicily East 6 Mediterranean

12 THE MEDITERRANEAN SITUATION The majority of Mediterranean waters are under the high seas regime. Territorial waters, established by coastal States over a width of 12 nautical miles The majority (6 nautical of Mediterranean miles for Greece) waters represent are under 16 % the of the high total seas surface regime. area. Few Territorial states waters, have asked established for an exclusive by coastal economic States over zone, a width but some of 12 have nautical declared miles (6 nautical new types miles of zones, for Greece) which represent are not covered 16 % of by the the total law surface of the sea, such area. as Few fishing states zones have or asked ecological for an protection exclusive economic zones. These zone, specific but some zones cover have declared 31 % of the new surface types of the zones, Mediterranean. which are not covered by the law of the sea, such as fishing zones or ecological protection zones. These specific zones cover 31 % of the surface of the Mediterranean. The Mediterranean covers the entire southern edge of the European Union. With The Mediterranean a surface area of covers 2.5 million the entire km², southern it is one of edge the of largest the European seas bordering Europe. Union. With It contains a surface numerous area of islands, 2.5 million which km², add it is 19 one 000 of km the of largest coastline seas to the bordering Europe. km of its It continental contains numerous shores. The islands, average which depth add of 19 about 000 km of m conceals coastline major to the disparities km A of relatively its continental narrow shores. continental The average shelf (with depth the of exception about of certain m conceals areas major such disparities. as the North A of relatively the Adriatic narrow Sea, continental the Strait of Sicily shelf and (with the the Aegean exception Sea) of contrasts certain areas with great such as depths: the North over of the m Adriatic in the large Sea, the basins, Strait with of Sicily records and of the over Aegean 5,000 Sea) m in contrasts some trenches. with great depths: over m in the large basins, with records of over m in some trenches.

13 THE MEDITERRANEAN SITUATION 23 Countries (Gibraltar, Spain, France, Monaco, Italy, Slovenia, Croatia, Boznia-Erzegovinia, Montenegro, Albania, Cyprus, Malta, Greece, Turkey, Lebanon, Palestinian Autonomous Territories; Syria, Israel, Egypt, Libya, Tunisia, Algeria and Morocco). Only a part of them are ICCAT CPC, while all of them are GFCM members

14 THE MEDITERRANEAN SITUATION Flying over the Mediterranean Sea for aerial surveys is not easy, because it is necessary to obtain many permits and each Country has different rules. At the moment, the political situation in some Countries is not the most adequate to apply for the aerial survey permit and this affected some efforts of the ICCAT Secretariat to overcome some problems we had in Phases 1 and 2. This fact caused the exclusion of some areas in Phase 4

15 THE MEDITERRANEAN CONDITIONS 1. It is still not clear if there are Mediterranean bluefin tuna sub-populations (it seems there are an E Atlantic-W Med subpopulation and an e med one) and which percentage of tunas are wintering in the Mediterranean (and, as a consequence, how many migrate from the Atlantic. 2. It is not clear the origin of the bluefin tunas passing along the western African coast before spawning and where they move for spawning. 3. Bluefin tuna can be considered a multi-spawner (within the same season). 4. It is well known that bluefin tuna spawning can potentially occur in most of the Mediterranean areas, except a very few ones. 5. Purse-seine fishery for adult bft logically takes place in areas of higher concentration of spawners, while longline fishery is able to cover much broader areas, but the latter also includes non-spawning tunas and then these data can provide less clear interpretations.. 6. It is strongly suspected that important displacements of bluefin tuna spawners, linked to peculiar oceanographic abnormalities, happened at least in the last two decades, affecting the distribution and fishery patterns. 7. It is well known that specific oceanographic conditions are necessary to induce spawning. 8. It is well known that strong winds during the spawning season not only prevent the purse-seine fishing activity and the aerial surveys, but also the stabilisation of the proper thermocline at the minimum necessary depth. 9. It is well known that, in recent years, spawning concentrations are initially in the eastern and in the southern Mediterranean areas, then in the central Mediterranean and finally in the Eastern Mediterranean, with a variable temporal overlapping and with yearly variations. 10. The situation in 2013 is partly different, with cold waters in most of the Mediterranean Sea.

16 SOME FIRST RESULTS 1. The first two surveyes allowed developing a preliminary and innovative prediction model for the concentrations of bluefin tuna spawners, based at the moment only on Sea Surface Temperature (SST); this is the only available model using real time data.

17 THE BASIC DATA FOR PHASE 4 Several areas were surveyed in 2010 and 2011 by ICCAT-GBYP: in total, they represented 11.97% of the total Mediterranean. Another area (Gulf of Lion) were surveyed in several years by IFREMER for juveniles.

18 THE BASIC DATA FOR PHASE 4 The map of the known spawning areas (both well-documented or potential) were finally available for SCRS, thanks to the work made by Piccinetti, Di Natale and Arena (2012).

19 THE BASIC DATA FOR PHASE 4 On this base, it was established the extended area to be potentially surveyed in 2013 (89.4% of the total Mediterranean area.

20 THE FINAL CHOICE FOR PHASE 4 Later, after checking the good-will of the various countries for providing the necessary permits for entering into their air spaces, we had to exclude Egypt, Montenegro and Albania, while Libya provided the declaration too late, when the new survey design was already done. We had also to exclude Palestinian territories, Israel, Lebanon and Syria.

21 THE FINAL CHOICE FOR PHASE areas to be surveyed with different intensities. 2. The initial date of the survey will be delayed due to permit issues.

22 THE FINAL CHOICE FOR PHASE 4 Four Companies have been selected: 1. GRUP AIR MED (Spain) for area A air spaces belonging to Algeria and Spain; 2. AIR PÉRIGORD & SARL ACTION COMMUNICATION (France) for area B air spaces belonging to Algeria, EC-France, EC-Italy and Tunisia. 3. PÉRIGORD TRAVAIL AÉRIEN (France) for areas E and G air spaces belonging to EC-Greece, EC-Cyprus, EC-Italy, EC-Malta, Tunisia and Turkey. 4. CONSORZIO UNIMAR (Italy) for areas C, D and F air spaces belonging to Croatia, EC-France, EC-Greece, EC-Italy. Tunisia and Turkey

23 ICCAT-GBYP: SCIENCE FOR SUSTAINABILITY THANKS!