The ECOTRANS oceanographic-fishing cruises will cover the following objectives: i) Sampling plankton (micro and mesozooplankton); ii) Sampling larvae of selected pelagic fish and iii) Trawl sampling (demersal) and bird census to determine the species and functional groups biomass and the trophic ecology of small pelagic fish, hake, monkfish and sharks at the NW Mediterranean ecosystem. The cruise (15 days of duration) will be conducted during the spawning period of the sardine (winter) in order to get their larvae.

The impact of trawling activity on a highly vulnerable habitat: the facies of Isidella elongata, a characteristic facies of Mediterranean deep sea communities, which is surprisingly a poorly known ecosystem.

The specific objectives of the campaign are: 1-To determine the abundance and spatial horizontal distribution of eggs and larvae of bluefin tuna in the Balearic Sea during the peak of spawning lay of the species in the area. 2-To determine the abundance and horizontal spatial distribution of potential predators of ABFT eggs, especially Pelagia noctiluca, and predators and potential preys of bluefin tuna larvae present in the surface layers above the thermocline, where the eggs and larvae of ABFT are distributed. 3-To characterize the hydrological scenario in the study period and area. 4- To determine the vertical distribution of eggs, larvae and postlarvae of bluefin tuna and Pelagia noctiluca along the daily cycle 5- To determine the daily mortality rates of larvae of ABFT in their different stages of development in the different environmental conditions prevailing in the study area 6- To get samples to study the trophic ecology of pre-juvenile and larval stages of bluefin tuna.

1-Determinar la influencia del escenario hidrográfico en la estructura, distribución y condición de las poblaciones larvarias de atún rojo Atlántico en el Mar Balear. 2-Evaluar la fiabilidad de los modelos de hábitat de puesta ya desarrollados para la especie, incluyendo las primeras versiones del modelo operacional. 3-Definir la ecología trófica de larvas y postlarvas de atún rojo Atlántico en el Mar Balear, considerando tanto su relación directa o indirecta con otros grupos planctónicos (picoplancton bacteriano, micro y mesozooplancton), como las interacciones entre larvas de túnidos de distintas especies y/o tallas. 4-Calcular un Indice Larvario para la estimación de la biomasa del stock reproductor. 5-Obtener coeficientes de calibración que permitan estandarizar los resultados obtenidos en muestreos cuantitatives de larvas de túnidos con distintos tipos de redes y metodologías de pesca. 6-Determinar la influencia ambiental en la estructuración vertical de las poblaciones larvarias de túnidos, y de ésta, considerando sus variaciones nictimerales y ontogenéticas, en algunos de los parámetros biológicos y fisiológicos de las larvas.

Estimating the abundance and population structure of the target species of the trawl fishery in the Mediterranean, identified in the MEDITS project (Annex I), studying the biology of exploited communities on the shelf and upper slope of the study area and the impact of fishing on ecosystems.

Estimating the abundance and population structure of the target species of the trawl fishery in the Mediterranean, identified in the MEDITS project (Annex I), studying the biology of exploited communities on the shelf and upper slope of the study area and the impact of fishing on ecosystems.

Estimating the abundance and population structure of the target species of the trawl fishery in the Mediterranean, identified in the MEDITS project (Annex I), studying the biology of exploited communities on the shelf and upper slope of the study area and the impact of fishing on ecosystems.

Estimating the abundance and population structure of the target species of the trawl fishery in the Mediterranean, identified in the MEDITS project (Annex I), studying the biology of exploited communities on the shelf and upper slope of the study area and the impact of fishing on ecosystems.

Estimating the abundance and population structure of the target species of the trawl fishery in the Mediterranean, identified in the MEDITS project (Annex I), studying the biology of exploited communities on the shelf and upper slope of the study area and the impact of fishing on ecosystems.

Estimating the abundance and population structure of the target species of the trawl fishery in the Mediterranean, identified in the MEDITS project (Annex I), studying the biology of exploited communities on the shelf and upper slope of the study area and the impact of fishing on ecosystems.