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The shape of sagitta otoliths was used to compare individuals of little tunny (Euthynnus alleteratus) harvested on board commercial fishing vessels from the coastal areas along the Eastern Atlantic, including the Mediterranean Sea. Fish sampling and selection was designed to cover possible seasonal changes and tuna size. The research encompassed both morphometric and shape analyses of left sagittal otoliths extracted of 504 fish specimens. Four shape indices (Circularity, Roundness, Rectangularity, and Form-Factor) were significantly different between two groups, showing a statistical differentiation between two clear spatial units. The degree of divergence was even more pronounced along the rostrum, postrostrum, and excisura of the generated otolith outlines between these two groups. One group corresponds to the samples from the coastal areas in the Northeast Temperate Atlantic and Mediterranean Sea (NETAM Area) and a second group from the coastal areas off the Eastern Tropical Atlantic coast of Africa (ETA Area). This study is the first to use otolith shape to differentiate tunas from separate spatial units. These results could be used to re-classify previously collected samples and to correct time series of data collected.

SUMMARY Data are presented on the Spanish fleet, fishing areas, catches, fishing effort, performance (CPUEs) and size distribution for purse seiner and baitboat. The total catch increased slightly by 3.1%. In 2019, there was a halt in fishing activity in July as a result of a check being carried out on bigeye quota consumption. More than 70% of sets were on “objects” and 25% on “free schools”. Median weights were slightly higher: yellowfin 10.7 kg (6.7 kg in 2018) (4.87 kg object and 32.11 kg free school); skipjack 1.7 kg (1.6 kg in 2018) (2.81 kg object and 2.42 kg free school) and bigeye 4.9 kg (3.5 kg in 2018) (3.4 kg object and 25.1 kg free school). Yellowfin presented a modal size of 42 cm for object and modal sizes of 42, 54, 152 cm for free school. Skipjack had a modal size of 42 cm on object and 44 cm for free school. Bigeye had a modal size of 44 cm on object and 42 and 152 cm for free school in 2019. RÉSUMÉ Des données sont présentées sur la flottille espagnole, les zones de pêche, les captures, l'effort de pêche, les performances (CPUE) et la distribution par taille pour les senneurs et les canneurs. Les captures totales ont légèrement augmenté de 3,1 %. En 2019, l'activité de pêche s'est arrêtée en juillet suite à un contrôle de la consommation du quota de thon obèse. Plus de 70 % des opérations étaient des opérations sous objets alors que 25 % des opérations étaient sur bancs libres. Les poids médians étaient légèrement supérieurs : albacore 10,7 kg (6,7 kg en 2018) (4,87 kg objet et 32,11 kg banc libre) ; listao 1,7 kg (1,6 kg en 2018) (2,81 kg objet et 2,42 kg banc libre) et thon obèse 4,9 kg (3,5 kg en 2018) (3,4 kg objet et 25,1 kg banc libre). L’albacore présentait une taille modale de 42 cm pour les opérations sous objets et des tailles modales de 42, 54, 152 cm dans le cas des opérations sur bancs libres. Le listao avait une taille modale de 42 cm pour les opérations sous objets et 44 cm dans le cas des opérations sur bancs libres. Le thon obèse

This document sets out the data for the Spanish fleet, strategies, fishing areas, catches of target species, effort, CPUEs, samplings and size distributions of target species. In 2017, total catch decreased by 5%. Twice as many sets have been carried out on objects than on free schools. More than 80% were conducted on objects and less than 20% on free schools. Average weights were: 5.3 kg for yellowfin tuna (3.8 kg on objects and 31 kg on free schools); 1.6 kg for skipjack (1.6 kg on objects and 2.03 kg on free schools); and 3.37 kg for bigeye tuna (3.27 kg on objects and 37.9 kg on free schools). The modal size for yellowfin tuna caught on objects is 46 cm and the two modal sizes for free school catches are 52 and 150 cm. The modal size for skipjack caught on objects is 42 cm and the modal sizes for free schools are 46, 55 and 64 cm. There is a single modal size for bigeye tuna caught on objects, i.e. 42 cm, and three modal sizes for free schools, i.e. 42, 114 and 146 cm.

En este documento se presentan datos de la flota española, estrategias de pesca, zonas de pesca, capturas de las especies objetivo, esfuerzos, rendimientos (CPUEs), coberturas de muestreos y distribuciones de talla de las especies objetivo y accesoria de la flota atunera de cerco y de la flota de cañeros de cebo vivo que faena en el Océano Atlántico Tropical. El número de barcos de cerco que operó durante este último año disminuyó en 2 unidades, aunque la captura total aumentó ligeramente durante 2016. En éste último año, se realizaron dos veces más lances a objeto que a banco libre. En términos de porcentaje el 68 % correspondió a Objetos y el 32 % a Banco Libre. Los pesos medios de los ejemplares capturados han sido: para rabil 8,5 kg (4,1 kg objeto y 25,5 kg banco libre); para el listado 1,97 kg (1,9 kg objeto y 2,67 kg banco libre) y para patudo 3,8 kg (3,3 kg objeto y 24,3 kg banco libre). El rabil (YFT) talla modal de captura 42 cm a Objeto (OB) y cuatro tallas modales de 42 cm, 58 cm, 106 cm y 138 cm para las capturas a Banco libre (FS) en 2016. El listado (SKJ) una talla modal de captura, 64 cm para Objeto (OB) y dos tallas modales de 64 cm y 72 cm para Banco libre (FS) en 2016. El patudo (BET) una única talla modal de captura 40 cm para Objeto (OB) y dos tallas modales de 42 cm y 94 cm para Banco libre (FS) en 2016.