SUBSCRIPT OBJETIVE 2

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1 SUBSCRIPT OBJETIVE 2 OBJECTIVE 2 : DESCRIPTION OF FISHERIES...37 MAROC (INRH)...37 DRIFT GILLNET...37 TRAP-NETS : Vessels, areas and fishing periods FISHING ROD : vessels, areas and fishing period SPAIN (IEO)...42 BLUEFIN TUNA,Thunnus thynnus...42 HAND LINE...42 PURSE SEINE...45 SURFACE LONG-LINE...48 TRAPS...48 BAITBOAT...53 SWORDFISH, Xiphias gladius...55 SURFACE LONG-LINE...55 ALBACORE, Thunnus alalunga...60 SMALL TUNA...61 TUNISIA (INSTM)...61 INTRODUCTION...61 DRIFT GILLNETS...62 PURSE SEINE...63 TRAP-NETS...66 LONGLINE...72 MALTA (NAC)...75 LONG-LINE...75 THE LUZZU (fishing boat)...80 MULTI PURPOSE VESSEL...81 LIBYA (MBRC)...83 TRAP NETS...83 SURFACE LONG LINE...85 PURSE SEINE...85 Aim 2 / 36

2 OBJECTIVE 2 : DESCRIPTION OF FISHERIES MAROC (INRH) The geographical position of Morocco and its mild climate, make of Moroccan waters the Northern distribution limit of a great number of tuna species, being an area of compulsory passage for the great tuna species during their migration between the Atlantic and the Mediterranean. Tuna fishing is esentially carried out during the two passages along Moroccan coasts, which take place from the Atlantic towards the Mediterranean in April-June and from the Mediterranean towards the Atlantic in July- November. In the Moroccan Mediterranean, tuna fishing is esentially carried out by trap-nets, drift gillnets and to a lesser extent by surface longline fishing. Furthermore, from 1994 a new craft fishing technique of bluefin tuna has been developped. This technique is the use of fishing rods in the Moroccan Mediterranean. In the next section, the main fishing techniques employed in the Moroccan Mediterranean for the explotation of these species are described. DRIFT GILLNET This gear is specifically used for the fishing of the swordfish during its migration through the Straits of Gibraltar. The longliner flotilla practising this activity is mainly set on the ports of Tanger (figure 1) and Nador. Today, these ports have 275 and 45 active longliners respectively, the average characteristics of which are described in figures 2 and 3. Description of the fishing gear : The gillnet is composed by multiple rectangular nettings which have a bolt-rope of floats on top and a bolt-rope of plumb on the bottom. The netting without plumb measures 100 m (figure 4). The most frequently found dimensions range from 2 to 3 km, and the predominant mesh size is about 400 m. The drop is limited between 11 and 15 arms. The swordfish fishing is a seasonal activity, since it coincides with the passage of the swordfish through the Straits of Gibraltar. It starts around the end of March and continues until November. The choice of the fishing area is determined by the availability of the resource all over the season, according to the different migration periods. Thus, between April and July, the fishing boats operating in the Straits are found in the West and from August to November, the gillnets are mostly drawn in the east of Straits. Fishing generally takes place at great depths (>200m). Aim 2 / 37

3 The fishing operation is divided into three phases. The first one consists in the spinning of the gear on the port side. The process starts by letting out the first luminous buoy, which is bound to the first extremity of the net, which will be thrown to the water later. After having wetted 10 pieces, a second luminous buoy is attached to the top bolt-rope of the floats and a big float is attached between two successive buoys. The operation continues this way until the whole engine is spun. The second phase consists in the wetting of the net. When this process is completed, we come to the tacking operation, which consists in throwing the net from the starboard side of the vessel by means of a net-hauler. The average duration of a haul is 12 hours. When the fish is scarce, the haul can be extended until three days. TRAP-NETS : Vessels, areas and fishing periods. Moroccan trap-nets are drawn in the two maritime coasts. In the Atlantic, the following trap-nets are legally installed : «Punta Negra», «Los Cenizosos», «Kénitra 1» and «Cap Spartel». In the Mediterranean, there is only one operational trap-net known as «Principé». These trap-nets deal with different phases in the migration of bluefin tuna. Thus, the Atlantic trap-nets target the bluefin tuna of genetic migration and they are drawn from April to June. On the other hand, the Mediterranean one targets the fish shoal of genetic migration as well as the trophic one and it is installed during a more extended period (April-October). The geographical situation of the Moroccan trap-nets is illustrated in figure 5. Description of the fishing technique: The trap-net is a trap gear, anchored in a fixed place when the migration of bluefin tuna takes place. It is generally drawn from the surface to depths ranging from 20 to 100 m. It is composed by a net barrier going from the coast to out to sea along several kilometres and also by a succession of nets allowing to poison the fish and lead it to the last siege called «chamber of death» or «Copo». The diameter of the mesh varies according to the different parts of the trap-net. The mesh size for the land net is about 90 cm and the size decreases progressively until it is 20 cm in the «Copo». FISHING ROD : vessels, areas and fishing period. This is a novel bluefin tuna fishery in the region of the Straits of Gibraltar. It has become more and more important since Fishing is distributed in four sites : Ksar sghir, Oued R mel, Diky and Ferdiwa, holding approximately one hundred vessels. Most of these vessels are wood boats, with a gross storage tonnage under 2 Tx (Fig. 9). They are equipped with a diesel motor on board. The fishing period normally lasts from April to October. Aim 2 / 38

4 Description of the gear and the fishing technique : Bluefin tuna fishing is carried out by a fishing rod with 2 to 5 baits. The thread employed is number 240 (2,4 mm diameter) and its length is 1000 m. The baits have a great size (reference 0 or 1). The ballast of the gear is assured by the big stones attached weakly to the thread, so that they can easily be let out when the tuna is being captured. The most commonly used bait is the mackerel. Depending on the size of the mackerel, one or two pieces are used per bait. The fishing operation consists of a series of manual liftings and descents of the fishing gear relatively fast, so that it appears that the bait is alive. When a tuna is captured, the boat is trawled far from the fishing areas. The fished tuna gives up after a fight that can last from 3 to 5 hours. Big tuna pieces are towed by the boat. The haul is generally short and does not exceed 7 hours. The fishery of bluefin tuna is carried out in deep areas (between 300 and 500 m). These areas are located at a distance of 3 to 5 km from the coast. Figura.1 General view of the longliner flotilla based in the Port of Tanger Aim 2 / 39

5 19% 8% 17% 55% <5 tjb 5-10tjb 10-15tjb >15tjb 24% 10% 27% 39% <50cv cv cv >150cv Figure.2 Characteristics of the active longliner flotilla in the port of Tanger 22% 42% 18% 18% <5tjb 5-10 tjb 10-15tjb >15tjb 11% 36% 31% 22% <50cv cv cv >150 Figure. 3 Characteristics of the active longliner flotilla in the Port of Nador Aim 2 / 40

6 Project FAO-COPEMED / Grandes Pelágicos 2000 Figure. 4 Picture of the gill-net used for the swordfish fishing 37º06'N 07º07'W ESPAÑA Cap Spartel Principe M Diq Los Cenizosos Punta Negra Hoceima Kenitra MAROC º50'N 01º53'W Figure.5 Geographical situation of the Moroccan trap-nets Aim 2 / 41

7 36% TJB 6% 58% <1tjb 1-1,5tjb 1,5-2tjb 3% CV 3% 94% <15cv 15-20cv >20cv Figure.6 Characteristics of the craft flotilla based in the Port of Ksar Sghir SPAIN (IEO) The Spanish fisheries of tuna and related species remained stable and without any change. Surveillance of the fleets fishing activity was carried out by informers and samplers at the RIM ports of the IEO and by observers onboard the long-line fishing vessels. The following is an up-to-date description of the tuna and related species fisheries. This description not only includes surface long-line fishing directed at the albacore, where we can see a stabilisation of activity, but also the semi-pelagic long-line fishing (piedra-bola) directed at the sword fish, whose activity has been described thanks to the work from onboard observers. This report also includes the fishing description of small tuna. BLUEFIN TUNA,Thunnus thynnus HAND LINE Bluefin tuna is captured by hand line (HAND- ICCAT code) from April to the end of the year in relatively coastal areas (20 miles) in the South Mediterranean, Valencia and Catalonia. All these zones, characterised by bottom elevations (100 meters depth), are areas of bluefin congregations with a FL of cm. There are two fishing seasons, Spring and Autumn, called "from straight" and "back", respectively. The gear has a nylon Aim 2 / 42

8 monofilament main line with a section of mm and with n 17 curved hook (Japanese type), baited with mackerel ( Scomber sp.) or sardine. Fishing can be done by hand or with the help of a manual brake. The fleet which pursue this type of fishing is very heterogeneous, and is currently composed of 189 boats with the following mean characteristics: TRB, HP and 8.71 m of length. Figure 7. Gear description and fishing technology: It is an artisanal gear composed of a hand-held line with weighted end and nº 0/1 or 1 hook of Japanese type (curved hook). Fishing by hand line is carried out by several artisanal boats from August to October. Main fishing grounds are those at Roquetas and the Strait of Gibraltar. This fishing modality was recently implemented in Estepona. A hook baited with Scomber scombrus or Sardinela aurita is attached to a line of about fathoms in length which, in turn, is attached to a main line of about 500 m in length. The gear, once rolled, is stored in wooden boxes. Currently fishing strategies involve double rigging, though sometimes three or four lines are employed by using buoys or auxiliary skiff. Two baited lines are shot close to tuna feeding grounds or secos (sea bottom plates). Each line is attached to a buoy or to the fishing boat and dead bait is thrown from the boat brumeo-, in order to attract tuna. Once hooked, tuna is brought onboard by means of a hand-held harpoon and a pulley. Figure 8 y 9. TRB 14% 8% 3% 8% 67% SIN DATO < > 50 ESLORA 32% 2% 8% 58% SIN DATO < >20 Aim 2 / 43

9 CV 11% 10% 8% 31% 40% SIN DATO < >150 Figure 7. Fleet of Hand Line (Mediterranean) Falseta Figure 8.- Bluefin tuna fishing by hand line. Al Brumeo. Aim 2 / 44

10 Figure 9.- Vessel type currently hand-line fishing in the area of the Strait of Gibraltar PURSE SEINE Bluefin tuna fishing by purse seine is effected from April to October between 42 N- 38 N latitude and from the coast through 05 E longitude. The fleet is composed of 6 boats whose mean characteristics are: TRB, 792 HP and m length. Figure 10 The net is 1400 m long and m high. It is a large single-panel multi-sectioned net, mounted to a float rope and a foot rope. The foot rope has a steel wire running through the pursing rings by means of which the bottom of the net is closed. Figure 11 TRB 43% 14% 43% < >100 Aim 2 / 45

11 ESLORA 14% 57% 29% < > 500 CV 57% 43% < 25 > 25 Figure 10. Fleet of Purse seine Aim 2 / 46

12 Figure 11.- Spanish embarkation of purse seine fishing of red tuna and Scheme. Aim 2 / 47

13 SURFACE LONG-LINE Bluefin tuna is a by-catch species on the surface long-lines for swordfish. Nevertheless, during May, June and July, there are some boats which, in the Balearic areas, target part of their effort on bluefin tuna catches. They introduce several modifications on their gear: bigger lines, bigger distance between ganging and number 17 curved hooks (Japanese type) baited with squid. TRAPS After reproduction in the Mediterranean, the bluefin tuna migrates (trophic migration) through the Atlantic. It is captured by traps which are located on both sides of the Strait of Gibraltar (Ceuta and La Linea). A traps is made up of a staked net comprising a leader net "rabera de fuera" which drives the fish through the cod end. Bluefin captured in July and August with this gear weight about 150 kg. In the last few years they are driven to fattening pools. Operative units, fishing area and fishing season. As regards fishing by traps, two main areas can be characterized. Four traps (Conil, Barbate, Zahara and Tarifa; Figure 12) are located in the southern Atlantic area. All these traps target bluefin tuna and tuna like species during their genetic migration towards spawning grounds (fase de derecho). Only traps located in Barbate and Ceuta catch tuna during feeding migration (fase de revés). As regards traps in the Mediterranean Sea, only the one in Ceuta fishes bluefin tuna (Figure 12). Aim 2 / 48

14 Figure 12.- Traps location. Fishing season during genetic migration (fase de derecho) lasts from April to June. As regards feeding migration (fase de revés), fishing season lasts from July to October. Catches are mainly composed of bluefin tuna and, to a lesser extent, swordfish and small tuna. Gear description and fishing technology. It is a fixed gear that intercepts bluefin tuna and tuna like when swimming towards spawning grounds (derecho) or feeding grounds (revés). These traps are set out along the southern and eastern Spanish coast and northern African coast. Figures 13 and 14 show a schematic drawing of a trap. A buche type trap is composed of a large net, named leader, open at the surface and several enclosures (raberas) and provided with various types of fish retaining devices which form the cuadro. Aim 2 / 49

15 The rabera de tierra or kettle net is about one mile in length and actual mesh size of about 60 cm. It is lowered into the water perpendicularly to the coast, where it is anchored. The cuadro, rectangular in shape, is set up parallel to the coast. It is about 205 m in length and 50 m in width, with the bag net (copo) of about 30 m wide. The entrance is provided with two retaining nets, endiches, which facilitate fish coming into the trap and avoiding fish going out. The aforementioned endiches are kept tense by means of steel ropes or cabestros. The cuadro can have three or four enclosures which, for the first case, are: cámara, buche and copo. The cámara and buche are divided by the mojarcio, steel rope extending through the surface and with smaller ropes, colinas, hanging down from it. These colinas are attached to the mojarcio door, a net at the bottom, used to concentrate tuna and to avoid tuna going back to the cámara. If the cuadro is composed of four enclosures, another net, the bordonal, is set up between the buche and the copo. Its characteristics and function are similar to those of the mojarcio. Mesh size for every enclosure belonging to the cuadro is about 30 cm, except for the copo which shows progressively decreasing mesh size: 12 cm as regards the safina clara, 8-10 cm for the safina espesa and 6-8 cm at the matador. The rabera de fuera is set up towards the sea. It is smaller than the rabera de tierra, attached to the cuadro by means of the legítima and contralegítima. It is L in shape and mesh size is similar to the rabera de tierra. Each surface net is provided with a float rope and anchored by means of ropes of about three times in length the bottom depth. As regards the foot rope, it is made of lead, stone or iron-chain attached along the lower edge of the net, so maintaining ground contact. Net height is higher than bottom depth for a percentage depending on tides and currents, sometimes reaching up to 30%. Netting ballast, floating response and depth are closely related to each other. Bluefin tuna and tuna like species do not pass through the raberas, they swim along the net and reach the entrance of the cuadro. Those tuna not entering the cuadro are collected by the legítima and contralegítima and sent back to the palmatorres, piece of netting near the entrance of the cuadro. As regards tuna swimming in the opposite direction to the entrance of the cuadro, they are intercepted by the rabera de fuera. When there are a sufficient number of fishes inside the cuadro, they are driven to the copo and the door is lifted. In order to avoid tuna going out, several pieces of netting triangular Aim 2 / 50

16 in shape, (blancas), are set. Once the assistant vessels are ready, the net at the bottom of the copo is lifted and the matanza starts. Fishermen, by means of hooks, bring fish on board. Two kinds of traps can be characterized regarding its location: ida or de derecho, targeting bluefin tuna during migration towards spawning grounds, and de retorno or revés, that targets bluefin tuna during feeding migration. Figure 13.- Trap schematic drawing. TRAPS CHARACTERISTICS. SOUTHERN ATLANTIC AREA. TRAP LATITUDE LONGITUDE DISTANCE FROM COAST DEPTH Nº 1 36º N 05º W m Nº 2 36º N 05º W m Nº 3 36º N 05º W m Nº 4 36º N 06º W m Aim 2 / 51

17 Figure 14.- Trap de derecho (spawning grounds) Aim 2 / 52

18 BAITBOAT This type of fishing is carried out during the Autumn season. The number of boats, from the North of Spain, is varies depending on the years (Figure 15). The areas for this gear are located in the Northern side of the Balearic Islands and the Alboran Sea (there, the targeted species is albacore). Lines are baited with Trachurus sp. and Engraulis encrasicholus. Bait is captured with purse seine and kept alive on board. The pole-lines and hooks used are of several sizes, depending on the length of the bluefin tuna. Figure 16 Photo Baitboad (BFT) Gear description and fishing technology: Trolling Boat This fishing modality, targeting bluefin tuna and albacore, is carried out by four vessels from Algeciras, one from Tarifa and several from the Cantabrian Sea. Hooks are baited with live bait: Trachurus spp, Sardina spp and Sardinella spp. Bait is maintained alive by on board fishponds, each fitted with artificial light and pumps for water oxygenation. Poles, currently made of wood, are of varying length. The line attached on the end of the pole is about one meter longer than the pole. Usually, pole- lines are attached to the deck by means of a which facilitate the pole movement when bringing the hooked fish on board. Smaller poles, Bambas, are not attached to the deck. They are about 1.5 m in length and baited with live bait. They are used to keep tuna near the vessel. Live bait fishing is carried out by means of a small purse seine. Later, once the fishpond, vessels go to fishing grounds where bluefin tuna or albacore shoals are detected by sonar. Fishing consists essentially in throwing bait in order to attract tuna. Each fisherman operating a pole has access to a small fishpond, constantly supplied by other fishermen. At the same time, water is thrown from the deck in order to mimic the presence of a huge shoal of potential preys and to distort sea surface layer, hence avoiding tuna trying to scape. If no tuna shoal is detected, four lines fitted with nº 5/0 hook and baited with dead bait are thrown to the sea, waiting for tuna. This fishing modality is named Machucha. Aim 2 / 53

19 TRB 34% 10% 56% < > 125 CV 7% 45% 48% < > 125 ESLORA 28% 25% 47% < > 125 Fig 15. Fleet of Baitboad (Algeciras) Figure 16. Spanish vessel Baitboad for tuna fishing Aim 2 / 54

20 SWORDFISH, Xiphias gladius SURFACE LONG-LINE Swordfish is targeted by surface long-line all year round. Nevertheless, maximum activity occurs during the summer and autumn months. The fishing area comprises the Spanish coast to 42 N latitude and 07 E longitude. The fleet comprises 145 boats which mean characteristics are: TRB, HP and m length, based in Andalucia, Murcia and the Balearic Islands. Most of them practice this kind of fishing with temporary licences. Figure 17 y 18. In figures figuras 17 to 20 it is shown the fishing gear diagram. The standard gear is made up of a nylon and plastic multifilament main line of mm section. Branches lines are connected to the main line with a distance between branches of about one fathom. Branches lines have a 1.60 and 1.80 mm section and a 7-10 fathom length with 1 hook. Near the surface the main line is supported by buoys which have bright signals and reflectors for location. Mean gear length is about 30 km ( actually up to 60 km is allowed ). Mean number of hooks is between 1000 and 2000 per fishing operation. Hooks are baited with Sardinela aurita and Scomber spp. Gear description and fishing technology: As regards the long line fleet fishing in the Mediterranean Sea, no standard gear can be characterized. Gear characteristics mainly depend on the vessel homing port as well as vessel carrying capacity. Fitting accessories may differ between vessels. Gear is composed of a main line, made of nylon or plastic, set parallel to the sea surface and with branch lines hanging down from it. These branch lines are attached to the shank of the hook by means of a thin line. Each gear is composed of a variable number of longlines, which have three lines connected by floats. Lines are 100 m in length, each bearing 4 or 5 branch lines about fathoms from each other. The branch lines are attached to nº 1 hooks by means of thin lines of varying length. As previously reported, mean characteristics are just for guiding purposes since no longline can be defined as a standard for the fleet fishing in the Mediterranean Sea. Main line is made of nylon and plastic, with cross section ranging from 2.25 to 3 mm. For branch lines, material and size are similar to the main line. Thin lines for attaching hooks have varying cross section, ranging from 170 to 180 mm. Sometimes reaching mm in cross section (140 mm as regards the artisanal fleet). Aim 2 / 55

21 Currently employed buoys are bottles and/or plastic balls. In order gears may be located by vessels, buoys are fitted with transmitters. From two years onward, using thermometer has become a common practice among fishermen. Currently employed bait is Scomber spp and Sardinella aurita. Gear total length depends on the number of hooks to be set, which in turn depends on the vessel characteristics such as carrying capacity, number of fishermen, fishing season, fishing strategy and environmental factors. On the average, longlines ( hooks) are set during winter and longlines ( hooks) in summer and autumn. The following table shows longline characteristics, material and length, for the gear used in the Alborán Sea and Strait of Gibraltar: Swordfish Surface longline in the Mediterranean Sea. Material and Length. ITEM ALGECIRAS MOTRIL Main line Branches Lines Hook mm mm Length 60 km 50 km Material Plastic 65 % nylon and 35 % plastic Length 1-3 fathoms 1-2 fathoms Distance fathoms fathoms mm mm Length 5-10 fathoms 5-7 fathoms Nº 1/0 and nº 1 Nº 1 and nº Gear is let down by nightfall and turned at daybreak by using a winch. Aim 2 / 56

22 Figure Spanish long-line fishing vessel in the Mediterranean Figure Jays and buoys tied to stern. Aim 2 / 57

23 TRB 22% 8% 10% 26% 34% SIN DATO < > 50 ESLORA 4% 11% 55% 30% SIN DATO < > 20 CV 31% 9% 16% 24% 20% SIN DATO < >150 Figure 19.- Fleet of Surface long line (Mediterranean) Aim 2 / 58

24 Figure Scheme of surface long-line fishing of the sword fish. Aim 2 / 59

25 ALBACORE, Thunnus alalunga The albacore (Thunnus alalunga) is caught in the western Mediterranean by Spanish vessels which fish seasonally using surface long-line fishing. This is a seasonal type of fishery which even occasionally fishes sword fish as an alternative when the catches of this species are rare or when there is a significant abundance of albacore. In some years the fishing period is divided into two determined seasons: spring and autumn. The number of embarkations which participate is variable depending on the year. The average fleet characteristics for the year 2000 were 29 TRB 11m of stem-to-stern length and 144 C.V. horsepower. The gear consisted of a single nylon filament main line of 1,1 mm calibre. The branches have a longitudinal section of 6m and 3m. The separation between the branches reaches 12m and the maximum number of authorised hooks is 10,000. The fishing areas (Figure 21) are distributed over well-differentiated zones in the area of the Balearic Archipelago and another one between Cape de Gata and the Alboran Island. The Spanish catches of albacore by means of surface long-line fishing in the Mediterranean were found to be between 200 tons and 25 tons depending on the year, with the average for the last 3 years of 50 tons VI - IX 44 BB PS HAND LL SURF LLALB 40 ESPAÑA IV -X 40 TRAP 39 VII - XI X-XI IV-VI X-XI VII VII-VIII V - VI V -VIII Figure. 21 Areas and fishing seasons of tuna and related species Aim 2 / 60

26 SMALL TUNA In addition to the tuna trap fishing of some small tuna species such as Bonito (Sarda sarda), Frigate Tuna (Auxis spp) and Atlantic blank skipjack (Euthynnus alletteratus), there also exists surface drift net fishing mainly directed at the Bonito and Frigate Tuna. The average catches for the last years reached 300 tons for Bonito and 600 tons for Frigate Tuna. The drift net, also called bonitera or melvera in some cases consists of a boltrope of cork and lead which respectively snare the net. One form is composed of a series of rags tied together totalling a maximum length of up to 1.5 miles. This is vertically plunged along the coast in order to intercept the passage of these highly migratory species. The mesh net used for small tuna is regulated by Ministry Regulation. The mesh has a minimum length of 10 cm. The most significant fishing period is in the autumn for the Frigate Tuna and in the winter and spring for the Bonito. TUNISIA (INSTM) INTRODUCTION The family of Scombridae is without any doubt the most important one in the Tunisian coast. We mention particularly bluefin tuna (Thunnus thynnus), little tuna (Euthynnus alletteratus), pelamid (Sarda sarda) and bullet tuna (Auxis rochei). The two former provide a local industry, as a great amount of this fish is sold for canning. Bluefin tuna and swordfish constitute preferential species for the export market. These products are mainly addressed to Japan and several European countries. The fishing gear used for their capture varies substantially and has gone through enhancements according technological progress. In fact, traces of tuna fishing in the Mediterranean coasts can be reported from many years back. Its fishing was practiced by means of harpoons until it slowly progressed to the rods, gillnets and encircling nets. Besides, the chroniclers of the old times (Aristotle, Plutarch, Elien etc) have extensively described this fishing, which provides us information about how important fishing was. Lookouts installed in towers informed fishers about the coastal movements of tuna; the fish were circled immediately. THOMAZI, 1947 indicates that Greeks used this technique and added the pratice of line fishing with baits wrapped by pieces of fabric or marine birds feathers. In this document, we intend to provide an exhaustive view of the fishing of great pelagics and to review the gears used in Tunisian waters for the caputre of this fish, which are nets and the floating longline. Aim 2 / 61

27 The applicable texts in terms of fishing policy in Tunisia contemplate four categories of nets: - Gillnets; which take the aquatic animals captured in their nets. They can be divided into: * fixed nets, which remain on the bottom and are not moved once drawn, for instance trap-netting for tunas. * floating nets, which are immersed or kept near the surface and move under the effect of the wind and the currents, for example drift gillnets or mernine. - Surrounding or encircling nets are those which, without touching the bottom, capture the aquatic species by circling them, for example the purse seine. - Benthic trawling nets are those trawled to the bottom regardless of the route and the way of towing, for example trawl and "tartarone". - Pelagic trawling nets, are those immersed and trawled without ever touching the bottom, for example in pelagic trawling. DRIFT GILLNETS In this group, we can distinguish the gillnets formed by a single netting and the trammels, formed by three nettings. The gillnet can be adrift on surface or near the bottom, or drawn in the middle of the water or on the bottom. The drift gillnet (Mernine) is used along some Tunisian coasts, especially during the genetic concentration of small tuna, such as the little tuna, the bullet tuna and the pelamid. It is a seasonal fishery. The nets, which do not usually exceed 1000 metres are generally set up at night, so that catch can be gathered early in the morning; twilight and sun rising are the ideal moments for good catch. These nets are set up in the direction of the wind and are adrift by the vessel. This barrier is invisible at night for aquatic animals in general, and for tuna shoals in particular (Euthynnus, Auxis, Sarda, Orcynopsis). Some of the pieces in the first line are captured and the rest turn back out to sea. (personal communication). The performance of this gear is very unstable; it depends on the effect of luck and also on the passage of fish and their density. In fact, a 1000 metres long net set up on the way of a fish shoal only captures a minimal fraction of it (1/20, according to the estimations of professional fishers). Gillnet fishing and drift gillnet are banned: - in the areas comprised between the Parallel of Borj Kélibia and the border between Tunisia and Lebanon. Aim 2 / 62

28 - in the area comprised between the Parallel of Borj Kélibia and the border between Tunisia and Algeria at a distance not exceeding ten miles from the base lines of Tunisian territorial waters. However, according to an order by the Prime Minister regulating fishery in Tunisia published in October 1995, the use of gillnet has been allowed in Tunisian waters. In compliance with EEC and FAO regulations, the length of these nets cannot exceed 2500 metres. However, the mentioned order does not fix their drop. The minimum mesh size is 30 mm. Regulations are on course in order to ban completely this fishing gear from the year 2000 on. PURSE SEINE Currently, around 70 seiner tuna fishing boats are dedicated to the tuna fishing along the Tunisian coasts (DGPA, 1998). These tuna fishing boats were introduced in Their hulls are mainly on wood with a length ranging from 15 to 38 metres and have a storage capacity ranging from to 298 tones; their crew is composed by ten people; the power of their diesel engines varies from 110 to 999 hp; they can reach more than 12 knots at full speed (Figure 22). The distribution of this flotilla by ports is shown in table 1. Table. 1 : Distribution by ports of Tunisian purse seiner tuna fishing boats Port Vessels Length Storage Power Bizerte 1 24,75 99,9 500 La Goulette 4 21,5-22, , Nabeul 1 19,5 64, Sousse 1 16,6 28,9 177 Monastir 7 15, , Mahdia , , Sfax , Gabès Houmt Souk Tunise 69 15, ,98-298, Aim 2 / 63

29 Répartition des longueurs des thoniers senneurs (Tunis ie, 2000) 7% 14% 33% 29% 17% 15-19,9 m 20-22,9 m 23-24,9 m 25-29,9 m >30 m Répartition des puissances des thoniers senneurs (Tunis ie, 2000) 9% 12% 35% 44% cv cv cv >700 cv Répartition des tonnages des thoniers senneurs (Tunis ie 2000) 16% 10% 25% 49% 17-49,9 tx 50-69,9 tx 70-99,9 tx >100 tx Figure 22.- Fleet of Purse seine Aim 2 / 64

30 Fig Purse seine tuna fishing boat Tuna fishing boats are known, firstly by the importance of the back deck for the loading of nets with an hydraulic crane (Figura 23). This crane is furnished with a multi-articulated and telescopic arm that can be oriented. At the extremity of the arm, a power block motor pulley is installed. Secondly, the gangway, set on an advanced position, is suspended by a fishing deck with a vigilance post, allowing the localization at sight of tuna on surface or jumping little tuna. Aim 2 / 65

31 a- The resources of purse seine fishing Although it is true that the statistic data of halieutic national catch are calculated according fishers, the fact is that it is extremely difficult to evaluate the current state of the exploitation of the resources taken by purse seiners. This is due to several reasons and our aim is to find solutions for them.: - Lack of data concerning the fishing effort (number of sea days) - Identification of specific captures - Difficulty for delimiting the areas frequented by these vessels. We aim at solving these gaps by organizing meetings dealing generally with the fishery of great pelagic species with the support of the administration and the backing of fishers in order to raise public awareness. A statistical leaflet is given out in the beginning of each campaign to ship owners or fishing skippers. TRAP-NETS In Tunisia, tuna fishing has been practiced nearly since the beginning of times. It was introduced by the Phoenicians; the Arabs of the 7 th century neglected it for a long time (PLUSQUELLEC, 1956). From the 19 th century this gear has experimented a rebirth. In fact we can situate around 1820 the first exploitations of Tunisian tuna fishing boats in Sidi Daoud, Cap Zebib and Monastir. Then, for a century and a half it became a purely Italian industry and until finally, trap-nets were granted to different concessionaires. In the beginning of the century, the number of operational tuna fishing boats was ten, not counting three other trap-nets granted in 1906 to Ras Salakta, at the outside of Menzel Temime and in the north of Mahdia, which did not seem to be exploited. These trap-nets were: Cap Zebib, in the east of Bizerte, Sidi Daoud, Ras El Ahmar, El Haouaria, Ras El Mihr, Ras Marsa, Monastir, Conigliera, Kuriat, Borj Khédija (not far from La Chebba). Today, only two trap-nets are exploited by l'office National des Pêches (ONP; National Fishery Office); that of Sidi Daoud and that of Monastir (Kuriat island). The Conception of trap-nets has been widely detailed in 1999 report and we sum it up here as follows: Trap-nets, like all fixed nets, are composed by a main netting, a dam net and an enclosure net. The enclosure net is composed by chambers; the last one of them is known as corpo or death chamber and it is disposed as a huge landing net. The operation consists in putting into practice the principles obtained from millenary verifications about the direction of displacements, which are always made in parallel to the side, generally below 35 m depth. In other words; to install net dams on the way of tuna shoals when they are migrating (to or back); the extreme closest to land goes from the shore in direction out to sea up to the trap-net body and the opposite extreme goes from the trap-net to out to sea. The tuna finds the obstacle, tries to avoid it and gets hooked in the chambers. The fishers erect the dams, circle the fish and lead it towards the chamber of death. When all the fish are supposed to be reunited in the last chamber, the upper bolt-rope of the net is lifted, and then fixed to the gunwales of the barge. Then the net is erected. Four vessels with twenty men on board of each lift slowly the bottom Aim 2 / 66

32 of the net and move it slowly towards the barge. Once the bottom is almost on surface, the tuna, feeling the breath shortage, are victim of a mad panic and collide, splashing water and blood all over. The rest of this operation, called Matanza consists of loading, manually or with the aid of hooks, the captured fish on board of one of the vessels. Figure 24 at 26 Legislation There are several special dispositions regarding tuna fishing boats detailed in the applicable texts of the Tunisian fishery policy. We summarize them hereafter: - The drawing period of each trap-net is fixed by means of an authorization. - Resulting from the demand presented every year before the 1st March by the concessionaire, the Agriculture Minister fixes a trap-netting area, the limits of which extend at least 4000 metres upstream and 1000 metres downstream from the point where the land extreme and the trap-net body meet. - The advanced extremity of the trap-net body will be signaled night and day in the middle of a vessel with deck and a 5 m height mast. Each boat will show two balloons in the daytime; the upper one will be white and the other one will be red. The vessel with deck can be replaced by a buoy showing the following signals: Trap-net in kuriat (Monastir) Coordinates: L = 35 47' 50'' N.G. = 11 01' 30'' E Orientation of the arm 352 Length of the arm 7550 metres Extremity signaled with a cylindrical buoy in horizontal black-and-white stripes. Cardinal buoy North White light in the dark, period of 6 seconds, range of 8 miles. Position L : 35 41' 15'' NG 11 00' 56'' E. Trap-net de Sidi Daoud Coordinates: L = 35 01' 33'' Orientation of the arm 300 Length of the arm 4500 metres N.G. = 10 53' 32'' E Extremity signaled by a vessel carrying two balloons, one over the other, 0.5 m diameter and at a distance of 2 metres from each other. The upper balloon will be white, the lower balloon will be red. At night, this vessel carries two vertical lights distanced by 2 metres visible around 360º, upper light white, lower light red. Aim 2 / 67

33 Figure 24.- Joint plan of the land sea installations of the tuna fishing boat in sidi Daoud. Aim 2 / 68

34 Figure 25.- Diagram of trap-netting in sidi Daoud Aim 2 / 69

35 Pêche au thonidés Pêche à l espadon Figure 26.- Approximate fishing areas of great pelagics according to the surveys carried out to fishers. Aim 2 / 70

36 Production of trap-nets These gears are based upon an ancestral principle: capturing the fish going to the Western Mediterranean to spawn in waters with a specific temperature and salinity. In their trajectory, tuna must cross the Sicily Channel, generally near the Tunisian Coast. Fishers knew that the tuna appeared from the third decade of May in Sidi Daoud and in the beginning of June in Monastir until the beginning of July. In the last years, variations in the dates of appearance of these animals have been observed and they are certainly due to atmospheric influences. As a matter of fact, this observation was perfectly verified in the thirties and not so much during the seventies. In the eighties, the appearance of bluefin tuna stopped in the middle of June. In the present, bluefin tuna are fished from the beginning of April until the end of May. Here we present a table the fishing periods of bluefin tuna in the trap-net of Sidi Daoud, illustrated by the histogram of the figure : With the aim of showing that this fishing is constantly suffering all kinds of consequences derived from the present international fishing conditions for bluefin tuna in international Mediterranean and Atlantic waters, we present a recapitulation of the production of Tunisian trap-nets in number of pieces since 1863 in the following figures. Year Beginning of fishing End of fishing th May 1 st June 24 th May 26 th May 3 rd July 4 th July 2 nd July 6 th July th May 22 nd May 19 th May 8 th May 28 th May 17 th May 6 th May 15 th May 2 nd May 5 th April 18 th April 27th July 20th June 16th June 31 st May 9 th June 13 th June 14 th June 15 th June 21 st May 27 th May 28th May (except for a fish caught on 27/07/2000) Table 2 Period of bluefin tuna catch in the Sidi Daoud trap-net. Aim 2 / 71

37 LONGLINE Nowadays, 40 vessels operate in Tunisian waters. The greatest part of the effort is concentrated along the north coast of Tunisia. The two ports known by the landing of swordfish are Tabarka and Bizerte. However, in 1998 two other cities have gained importance in terms of landing. These cities are Teboulba and Mahdia. The landings in these two ports have reached 40% of the national catch, which varies between 200 and 400 tones. Figure 27 Port Unités (m) Gauge (t) Power (hp) Tabarka Bizerte 13 10,7-16,7 7-20, La Goulette Nabeul 12 10,7-16 9, Sousse 2 10,5-12 8, Monastir , Total ,7 7-20, Tabl. 3- Distribution of Tunisian longliners targeting swordfish fishing Longline is a Japanese tecnnique which has been successful in Japan. It needs very few sailors for its manouvers and the expenses for its maintenance are low. This technique is spreading more and more along our coasts and it is used the whole year. Conception The longline is the fishing gear for the capture of swordfish and is composed by several units; each unit has a principal rod, to which some branches are attached. At the extremity of each unit there is a float. The extremities of the whole longline are marked by a float at the beginning and a signal (ensign) at the end. The main rod is a braided textile thread, with a diametre of 6 millimetres. Its length depends upon the number of coupled units. Each branch is composed of three parts (figure 28): - the two first parts are 10 metres long threads which have a diametre ranging from 4 to 5 milimetres. They are attached one after the other and the second thread has a ballast. Le signal est formé d'une tige en bois de 4 à 5 mètres de long, munie d'un pavillon rouge à l'extrémité supérieure; deux bouées sont attachées à la tige à 3,5 mètres de l'extrémité Aim 2 / 72

38 supérieure assurant la flottabilité du signal; un lest de 6 à 7 Kg est attaché à la partie inférieure assurant le maintien du signal en position verticale dans l'eau. Répartition de la puissance des palangriers (pêche à l'espadon) 5% 2% 33% 44% 16% cv cv cv cv >180 cv Réaprtition des longueurs des palangriers (pêche à l'espadon) 14% 7% 26% 53% 10-11,9 m 12-13,9 m 14-15,9 m >16 m Répartition des tonnages des palangriers (Pêche à l'espadon) 11% 11% 16% 32% 30% 7-9,9 tx 10-12,9 tx 13-15,9 tx 16-18,9 tx >19 tx Figure 27.- Fleetof long-line Aim 2 / 73

39 Figure 28 - Floating longline Aim 2 / 74

40 Regulation There is no particular national regulation for this way of fishing except for the recommendation made by the CICTA adopted by Tunisia as contracting country and which deals with fishing in the Mediterranean during the months of spawning. According to this recommendation of the CICTA, the bluefin tuna fishing is forbidden in the said area during the period from July 1 st to the July 31st by means of great longliners measuring more than 24 metres long. LONG-LINE Bluefin Tuna MALTA (NAC) Bluefin tuna (Thunnus thynnus) fishing season in Malta starts during the month of May and extends until the month of July. The upsurge in bluefin tuna landings came about as a result of the tapping of the Japanese market in1989 and in fact one will find that from a mere 48,669 kilos in1990 landings shot up to 353,014 in 1995 as a result of diversification of the fishing effort by the larger vessels. The decrease in landings during the last 3 seasons may be attributed to the large presence of tuna purse seiners off the Maltese Islands. In 1998 tuna were targeted by 52 multi-purpose vessels ranging from 10 to 20 metres, 150 full-time fishermen and part-time fishermen. The total landings were 244,749 kg of which 108,768 kg (45 %) was exported. The decrease in landings from 1995 onwards may be mainly attributed to the large presence of foreign tuna purse seiners just off the Maltese Islands, which carry out a very efficient operation. The gear used is drifting surface longline and is baited with Atlantic mackerel and/or Japanese squid. The maximum number of hooks set in a longline is 2,500 and this depends mostly on the size of the boat. The lines are set during the afternoon and the operation goes on till around 8.00 p.m. since fishermen reckon that this is the prime time for the fish to bite. The lines start being retrieved from around p.m. onwards. Fishing is undertaken to the West, South and South East of the Maltese Islands between the 35 th and 36 th parallels with the following parameters: on the Western limit Latitude 35:52:00 Longitude 13:30:00 (50 miles from Marsaxlokk harbour) to the southern extremity Latitude 35:21:58 Longitude 12:25:24 (30 miles from Marsaxlokk harbour) to the Aim 2 / 75

41 south east Latitude 35:22:74 Longitude 15:03:14 (37 miles from Marsaxlokk harbour) which covers approximately 2,000 square miles (Busuttil, C 1999, pers. comm.). At the beginning of the season, i.e. in May, the effort is undertaken mainly in the South West area of the region and consequently further to the east according to the normal movement of the bluefin tuna. The season ends in July. The main landing zones are Marsaxlokk, St. Paul s Bay and Marsascala harbours in Malta, whilst those in Gozo are Mgarr and Marsalforn harbours. Marsaxlokk is the harbour where most of the tuna is landed. The tuna is usually gutted (removal of internal organs and gills) on board and is unloaded at the fish market in Malta. The tuna for export is the prepared (removal of head and bones) and exported directly either by plane or by boat in freezer containers. The potential catch size per boat per season for the Maltese fishermen amounts to approximately 80 bluefin tuna and ranges between 50 and 100 according to the year. The long-line ( konz ) (Figure 29) is the most popular method for tuna fishing in our islands. In August 1953, the British Government decided to invite Mr. T.W. Burdon, then the deputy Director of Fisheries in Singapore, to prepare a report on the fishing industry in our islands. Mr. Burdon suggested that tuna fishing should be carried out by the long-line, as this was a less expensive implement than the tonnara and did not require such a large number of fishermen working together concurrently. It was however only in the sixties that this fishing system became widely used. The long-line, which is of a surface drift type, can vary from 20 kilometers to 120 kilometers in length; hence its name. It is usually kept afloat ( konz tal-wicc ). The main line is usually monofilament with a diameter ranging between mm. Along the main line, there are the side lines / snood ( brazzol ) which are about 6 m long. The snoods are also made of monofilament but with a smaller diameter of around 1.6 mm. The distance between two consecutive snoods is usually around 54 m. The snoods are alternatively fitted with a small white buoy. Floating flags tied to long bamboo rods are used along the line and these begin to vibrate vigorously when a fish is caught. At the end of each side line, there is a hook to which the bait is attached. The hooks used are of the Japanese round type. The number of hooks used by each fishermen is usually in the region between 1500 and The length of long-line and number of hooks used depend on the vessel and the crew. The bait used for fishing for bluefin tuna includes Atlantic mackerel and squid, which are alternatively attached to the hooks. The squid provides a better bait for the bluefin tuna but is in turn much more expensive. Early in the afternoon, casting of the long-line starts with a speed of about 7 knots. It begins at a distance of about 15 kilometers from the coast and may take till about 8:30 in the evening, i.e. just before sunset. Aim 2 / 76

42 Fig. 29 Typical Maltese Surface Longlines - BFT Hauling starts at around 10:30 and is done with special belt hydraulic winches. The master of the boat uses a strong light fixed to the bow of the boat to spot the small marker buoys. Hauling is done at a speed of about 6 to 7 knots. The time spent on hauling depends on the amount and type of fish caught because if for example the fish caught are still alive, it would take much longer to haul the fish on board. Since the long-line is very long and consists of many hooks, it is very liable to get entangled. It is therefore wound up in a circular basket and the hooks are attached to straps of cork which are fixed around the rim of the basket. The long-line is then ready to be used again without any problems. Swordfish Since in Malta registration of all boats is required by law, with the help of Fisheries Officers, the boats which are yearly engaged in tuna fishing were identified and for each fishing craft, the following information was collected from the respective owners: Craft Registration Number Port Crew Number of Hooks Type of Vessel Length of Vessel (m) Width of Vessel (m) Draught of Vessel (m) Propulsion (hp) Table of Fishing Vessels Data Forms Aim 2 / 77

43 Craft Registration Number Figure 30 Typical Maltese Surface Longlines - SWO The craft registration number of each vessel was obtained from the Fisheries Department since in Malta registration of fishing boats is required by law. The owners of the three fishing vessels were contacted and asked to help with this project by allowing an observer on board to stay on the fishing vessel during fishing. The observers on board were taught how to collect the necessary information by the procedures described below. Port There are various ports scattered around the Maltese Islands as shown in Figure 31, where tuna fishing vessels can be anchored but the main ones include: Mgarr in Gozo and Marsaxlokk in Malta. During the data collection exercise, the port from where each fishing vessel operates was recorded. Aim 2 / 78

44 Figure 31 Main Fishing Ports Number of Hooks In Malta, tuna is caught by means of the surface drift long-line. This is usually made up of a main line along which are the side lines. At the end of each side line, there is a hook (Fig. 32) to which the bait is attached. The number of hooks used for each fishing trip is very important for Fishery Statistics in order to calculate the Catch per Unit Effort. Aim 2 / 79

45 Figure 32 Hook used in catching BFT THE LUZZU (fishing boat) The luzzu is a typical Maltese fishing boat. It is fusiform in shape (tapering at both ends) and carvel-built with a vertical stem pot at the prow which s slightly higher than the stern. Both the bow and the stern rise above the rest of the vessel in order to protect the crew from the spray of the sea when the boat is moving against the waves. The luzzu-type boat was introduced in Malta in the beginning of this century when some men from Mosta brought a design of an English fishing boat to Marsaxlokk and boats started being built according to this new design. Initially, as all other fishing boats, the luzzu was propelled by sails and oars, but, as motor engines were increasingly applied to the vessels the number of luzzijiet increased considerably. Today, many of them have a cabin installed, and a store for fish. The name luzzu possibly originates from lozzu (figure 33) which is the Maltese name given to the Mediterranean barracuda. Like this fish, the luzzu is fusiform in shape; the original name of this fishing boat was indeed lozzu and not luzzu. The length of this fishing boat usually reaches 15 m. Registered luzzijiet belonging to full time and part time fishermen, as on 31 December 1998, amounted to 270 in Malta and 78 in Gozo. Aim 2 / 80

46 Figure 33. The Luzzu (fishing boat) MULTI PURPOSE VESSEL The other fishing vessels used for bluefin tuna fishing are the launch or multi purpose vessels. On 31 December 1998, there were 59 of them registered in Malta and 20 in Gozo. These launches are all equipped with a cabin and are also widely decked. They are moderately fast vessels, with plenty of comforts for the crew and ample space for storing and handling all the various fishing implements and the captured fish. The data collected is summarized in Figure 34, 35, 36 and 37 below. Aim 2 / 81