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j Annex VI. Report of Spain on the P. bogaraveo fishery (Juan Gil Herrera) SRWG on shared demersal resources Ad hoc Scientific Working Group between Morocco and Spain on Pagellus bogaraveo in the Gibraltar Strait area Málaga (Spain), 22 July 2010 ITS BIOLOGY Spanish information about the red seabream (Pagellus bogaraveo) fishery in the Strait of Gibraltar Region Juan Gil Herrera Growth: -Otoliths reading -Tagging programmes (recaptures) Red seabream is considered a slow growing species. Gueguen (1969) reported a maximum age of 20 years. In the Azores Islands a maximum ageof15yearswasobservedina56cmlength fish (Krug, 1994). In the Strait of Gibraltar VBGF parameters were also estimated from the increasing size of 271 recaptures. Part I: Biology and Fishery THE SPECIES VORAZ: Pagellus bogaraveo (Brünnich, 1768) Inshore waters above various types of bottom (rocks, sand, mud) to 400 m (Mediterranean) and 700 m (Atlantic); young near the coast, adults on the continental slope specially over muddy bottoms. Omnivorous, but feed mainly on crustaceans, mollusks, worms and small fish. Protandric hermaphrodites. Adults move towards the coast up to the edge of the Taxonomy: continental shelf to spawn from January to June. Important foodfish: Superclass GNATHOSTOMATA marketed mainly fresh. Class ACTINOPTERYGII Subclass NEOPTTERYGII Distribution: Eastern Atlantic (Norway, Division TELEOSTEI Strait of Gibraltar to Cape Blanc in Subdivision EUTELOSTEI Mauritania, Madeira, Canary Islands) Superorder ACANTHOPTERYGII and western Mediterranean (rare Order PERCIFORMES beyond the Sicilian Strait). Family SPARIDAE Genus Pagellus (Valenciennes, 1830) ITS BIOLOGY ∞ φ Similar growth patterns can be assumed for the red seabream in all the areas. This assumption does not denote a single stock: Growth patterns are similar but not the same! ITS BIOLOGY ITS BIOLOGY Testicle Stock identity: Reproduction: -Tagging programmes Ovary -Hermaphroditism -Genetic - Spawning season -Viral studies -Length at first maturity ICES considered three different components for this species: a) areas VI, VII, and VIII; b) area IX (where the case study fishery take place) and c) area X. This separation does not pre-suppose that there are three different stocks of red (blackspot) seabream, but it offers a better way of recording the available information (ICES WGDEEP Report 2008). SPAIN Hermafroditas Hembras Machos 100% 75% 50% 25% 0% I II III IV V VI VII VIII IX X XI XII Machos Hembras Hermafroditas 100% 75% 50% The smallest specimina are mainly males, then an important part of individuals change it sex and became females. Spawning seems to take place in the Strait of Gibraltar area, where the fishery is carried out. The spawning season in the Strait of Gibraltar seems to take place during the first quarter of the year (Gil, 2006). The period coincides with those obtained by Krug (1994) for the Azores Islands and from previous studies in the Cantabrian Sea by Sánchez (1983), Alcaraz et al. (1987) and Castro (1990). MEDITERRANEAN SEA 25% ATLANTIC OCEAN 0% 25 27 29 31 33 35 37 39 41 43 45 47 49 51 53 MOROCCO 31
500 m 300 m 100 m 30 m Cádiz 300 m 100 m Conil Barbate La Línea Algeciras Tarifa 10 7 456 11 9 8 12 26 13 27 28 29 14 3 2 1 33 34 36 35 38 151617 18 37 39 40 41 1920 Estrecho de Gibraltar 300 m 43 21 22 2425 23 42 Ceuta Tanger Tetuán Estepona 30 m 100 m 300 m 500 m Fuengirola 500 m 300 m 100 m ITS BIOLOGY STRAIT OF GIBRALTAR SPANISH RSB FISHERY (AND MARKETING) Length at first maturity estimates (Gil and Sobrino, 2001) 1.0 0.8 Males 0.6 0.4 0.2 L 50 a = -11.16 b = 0.37 r 2 = 0.73 L 25 = 27.18 L 50 = 30.15 L 75 = 33.11 L 90 = 36.08 0.0 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 Total length (cm) 1.0 0.8 a = -14.47 0.6 b = 0.40 r 2 = 0.82 L 25 = 33.02 0.4 L 50 = 35.73 L 75 = 38.44 L 90 = 41.05 0.2 L 50 0.0 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 Total length (cm) Females “Voracera”fleet Artisanal ±100 boats Main ports Commercial cat. Tarifa Burro Algeciras Tamaño Mediano Pequeño > 1.300 grs. 850 a 1.300 grs. 550 a 850 grs. 350 a 550 grs. ITS BIOLOGY STRAIT OF GIBRALTAR SPANISH RSB FISHERY Feeding: -Study difficulties (bait!) -Main preys -Predators (without taking humans into account!) Not too much studies. The overall diet is not very diverse, mainly composed by Sergia robusta as main prey while the order teleosts Stomiiformes can be considered as a secondary prey. Other appearing species are Lampanyctus crocodiles, Lophogaster typicus, Argyropelecus hemigymnus and Chauliodus sloani (Polonio et al., 2008). Main predators are unknown in the Strait of Gibraltar waters but maybe dolphins’ predation should be taken into account (personal communication from Ceuta veterinary). Studies in Azores (Gomes et al., 1998) cite that Conger conger, Raja clavata and Galeorhinus galeus should be considered as potential predators (all three species are present in Strait of Gibraltar area). STUDY AREA STRAIT OF GIBRALTAR SPANISH RSB FISHERY Strait of Gibraltar: Artisanal longline fishery targeted red seabream has been developed along the Strait of Gibraltar area. Actually the Spanish fishery covers almost the 70 % of the landings for the speciesintheSubareaIX. 36.60 36.40 Gulf of Cádiz SPAIN Spanish red seabream fishery in the Strait of Gibraltar is almost a monospecific fishery with one clear target species. Pagellus bogaraveo represents the 74% from the total landed in average percentage which constitutes a fleet component by himself (Silva et al., 2002) 36.20 36.00 35.80 30 31 32 Alboran Sea 35.60 MOROCCO -6.60 -6.40 -6.20 -6.00 -5.80 -5.60 -5.40 -5.20 -5.00 -4.80 -4.60 32
Page 2 and 3: CopeMed II - ArtFiMed Technical Doc
Page 4 and 5: Preface The CopeMed II Project on C
Page 6 and 7: Preparation of this document This d
Page 8 and 9: 1. Opening of the meeting and desig
Page 10 and 11: For the collection of data on catch
Page 12 and 13: The Spanish red seabream fishing fl
Page 14 and 15: of the series. ICES recommended cat
Page 16 and 17: Table 1. Comparison of the data/par
Page 18 and 19: 11.Conclusions and recommendations
Page 20 and 21: Annex I. List of participants INRH
Page 22 and 23: Annex III. Introduction and Objecti
Page 24 and 25: of the activities of the GFCM Sub-C
Page 26 and 27: Table 3: A proposal for an updated
Page 28 and 29: Annex IV. Rapport sur l’état de
Page 30 and 31: Alors que l’engin utilisé par le
Page 32 and 33: 8.3 Indices d’abondance L’évol
Page 34 and 35: 9- Recommandations d’aménagement
Page 36 and 37: 35% 11% 7% 26% 21% Dorade rose Pagr
Page 40 and 41: STRAIT OF GIBRALTAR SPANISH RSB FIS
Page 42 and 43: STRAIT OF GIBRALTAR SPANISH RSB FIS
Page 44 and 45: INDICE - Presentación del Sistema
Page 46 and 47: Valoración de los Recursos Pesquer
Page 48 and 49: RESULTADOS: Estimación Rendimiento
Page 50 and 51: -Consideración de nuevas posibilid
Page 52: 45

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