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The reproductive biology of the European hake (Merluccius merluccius, Linnaeus, 1758) was studied on the eastern central Atlantic Moroccan coast from November 2001 to December 2003. The sex ratio was close to 1:1 for the specimens with a total length of less than 45 cm. European hake spawned all year round, though two spawning peaks were recorded with a certain interannual variability: the first and main peak in winter and a secondary intermittent peak in summer. Length at first maturity was estimated as 28.6 cm and 33.8 cm total length for males and females, respectively. These values are closer to Mediterranean than Atlantic hake values. The mean batch fecundity was 299872 eggs ind–1. The relative batch fecundity was estimated as 228 eggs per gram of gutted weight. Batch fecundity increased proportionally with fish length and weight. The batch fecundity of European hake in the Moroccan Atlantic area is higher than that in northern Atlantic and northwestern Mediterranean areas., Se ha estudiado la biología reproductiva de la merluza europea (Merluccius merluccius, Linnaeus, 1758) en la zona central del Atlántico Oriental de la costa de Marruecos durante el período de noviembre de 2001 a diciembre de 2003. La proporción sexual fue cercana a 1:1 para los individuos de talla total menor de 45 cm. La merluza europea se reproduce durante todo el año. Se han detectado dos picos de puesta con una cierta variabilidad interanual: el primero y más importante en invierno y otro pico secundario intermitente en verano. La talla de primera madurez se estimó en 28.6 cm y 33.8 cm de longitud total para machos y hembras respectivamente. Estos valores son más cercanos a los observados para la merluza en el Mediterráneo que a los del Atlántico. La fecundidad parcial media fue de 299872 huevos ind–1. La fecundidad parcial relativa se estimó en 228 huevos por gramo de hembra referido al peso eviscerado. La fecundidad parcial se incrementó proporcionalmente a la longitud y peso del pez. La fecundidad parcial de la merluza europea en el área atlántica de Marruecos, muestra valores más altos que en las áreas del Atlántico situadas más al norte y del NW Mediterráneo.

Eastern boundary upwelling ecosystems: integrative and comparative approaches, 2-6 June 2008, Las Palmas, Gran Canaria, Spain, The Large Marine Ecosystem of the Canary Current (CC) is one of the four major eastern boundary upwelling systems of the world ocean, and thus an area of intensive fisheries activity. The coastline is separated into two distinct areas -the Iberian coast and the NW African coast- at the Strait of Gibraltar, where the Mediterranean Sea and the Atlantic Ocean exchange water. The two areas share similarities in local oceanography, productivity and fisheries, but also exhibit their own particularities. In the northern most Iberian region, the Rías Baixas represent a unique ecosystem, strongly interacting with the coastal upwelling and amplifying its signal. Although seasonality in the Trade wind regime is more pronounced in the northern and southern extremes of the CC, the whole region exhibits high annual productivity and fish population yield. Nevertheless, a large fraction of the productivity is presumably lost to the open ocean. In particular, the NW African shelf between Cape Guir (32 N) and Cape Blanc (21 N) exhibits numerous upwelling filaments. These appear topographically generated in general and those arising south of 28 N result largely from the interplay of the coastal jet with eddies shed downstream the Canaries Archipelago. Filaments facilitate nearshore-offshore exchange of water parcels and properties and a net productivity loss. In recent years, considerable information has been gathered from these coastal ecosystems, and several review papers have been published on plankton biology, biogeochemistry or regional fisheries. Here, we present an updated global review of the CC, covering aspects ranging from hydrography, through biogeochemistry to trophic interactions and fisheries, all of which are affected by processes occurring on distances from mesoscale to large scale and over periods from days to decades. The synthesis will highlight recent major advances in experimental studies, both over the coastal shelf and in the open-ocean transition zone, as well as in modelling exercises. Ongoing numerical models range from large-scale and regional circulation off Iberia and NW Africa to coupled physical-biological models looking at plankton productivity or fish population dynamics