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Length-weight relationships (LWRs) for six fish species caught from tidepools in an intertidal rocky shore in the Gulf of Cadiz are presented. This study presents the first data on LWR for Clinitrachus argentatus (WT = 0.0069 * TL3.077), Coryphoblennius galerita (WT = 0.0051 * TL3.409), and Parablennius incognitus (WT = 0.0090 * TL3.113) outside the Mediterranean Sea and adjacent eastern waters. The data of LWRs for juveniles of Symphodus roissali (WT = 0.0117 * TL3.091), Serranus scriba (WT = 0.0165 * TL2.881), and Diplodus cervinus (WT = 0.0152 * TL3.060) are also presented for first-time. Due to fish body shape may vary during growth in relation to size, studies covering a specific size range relating to life stage can be useful to estimate the LWRs for different development phases. The findings of this study fill the gap in LWRs data for immature fish in S. roissali, S. scriba and D. cervinus. Moreover, because intertidal zones and their adjacent subtidal areas represent nursery grounds for species that eventually recruit to coastal fisheries, the LWRs estimates for other species can also help to understand the population dynamics and conservation for native fish species.

The reproductive cycle of seven common species (Gobius paganellus, Gobius bucchichi, Gobius cobitis, Parablennius sanguinolentus, Salaria pavo, Tripterygion tartessicum and Symphodus roissali) on rocky shores in the Gulf of Cadiz and their relationship with the sea surface temperature (SST) is analysed. Partial data on Scorpaena porcus are also given. Fecundity of these short lifespan species shows a positive linear correlation between the number of oocytes and an increase in female size. Spawnings are concentrated in the first 7 months of the year. An analysis of reproductive growth with respect to SST shows that water temperature in the winter months affects the timing of the onset of reproduction in most species. Recruitment is takes place throughout the year, but a temporal segregation within different families occurs in their spawning as well as recruitment.

The structural patterns of the mesozooplankton community of San José Gulf (SJG), a one of a kind semi-enclosed basin located in the northern margin of the Valdés Peninsula (Argentine Patagonia), were studied by means of semi-automatic image analysis. Samples were obtained bimonthly during the warm season (October 2012?April 2013) at stations distributed on a regular grid. Cluster analyses outlined two spatially consistent groups of stations showing similar patterns when based on physical (SST, Chl-a, and bottom depth) and community structure (abundance, biomass, and slope of the size spectra) descriptors, each broadly distributed on one of two previously described hydrographic domains formed by the interaction of tidal circulation, coastal morphology, bottom topography, and seasonal vertical stratification. Examination of the slope of the mesozooplankton size spectra revealed that the stratified waters of the East Domain sustain higher proportions of small organisms and higher biomass, suggesting potentially low trophic transfer efficiency compared to its vertically-mixed West counterpart. Three-clustering analyses resulted in still spatially consistent groups of stations when based on the community descriptors, revealing the existence of a transition zone, presumably resulting from intermediate hydrodynamic conditions. Principal component analysis revealed that biomass of cladocerans modulates the size spectra and is related with distances from sampling stations to SJG´s mouth. Overall, a consistent spatial correlate was found between physical conditions of water masses and the structure of the mesozooplancton community contained within. Fil: Hernández Moresino, Rodrigo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentina Fil: Di Mauro, Rosana Patricia. State University of Louisiana; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Crespi Abril, Augusto Cesar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentina. Universidad Nacional del Comahue; Argentina. Universidad Nacional de la Patagonia; Argentina Fil: Villanueva Gomila, Gabriela Lujan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentina Fil: Cano Compaire, Jesus. Universidad de Cádiz; España Fil: Baron, Pedro Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentina

The present work on the feeding ecology of Scorpaena porcus according to season, sex and size, is the first study carried out in the rocky intertidal in the NE Atlantic. Previous studies were carried out with fish collected in fishing grounds from Mediterranean areas. A total of 106 fish were caught in monthly samplings from April 2008 to July 2010 in three areas of the rocky intertidal zone in the Gulf of Cadiz. The diet composition varied with season, size and sex. Shrimps were the main diet resource during all year, but other prey were also important depending on the season. As the size of fish increased, predation on smaller crustaceans decreased and consumption of larger crustaceans and fish augmented. Females and males based their diet on shrimps, while indeterminate fish fed largely on amphipods. No significant differences were found between feeding intensity and season, size and sex. Nevertheless, the PERMANOVA results showed that the number of prey is affected by the interaction between sex and size class. Our results highlight that S. porcus is a stenophagic species that shows a gradual segregation in the use of resources as it grows, which indicates there is no intraspecific competition in the rocky intertidal.

This paper describes the use of resources and diet of nine resident fish species in the rocky intertidal zone of the Gulf of Cadiz and examines whether their populations are affected by trophic competition. A stomach content analysis of the nine species revealed that only one was herbivorous ( Parablennius sanguinolentus ), while the rest were mainly carnivorous ( Gobius bucchichi , Gobius cobitis , Gobius paganellus , Zebrus zebrus , Salaria pavo , Lepadogaster lepadogaster , Scorpaena porcus and Tripterygion tripteronotum ). The most frequently consumed prey were amphipods, isopods, polychaetes, decapods, chironomids, tanaidaceans, gastropods, copepods, cumaceans and ostracods. In most species, the occurrence of polychaetes and molluscs was higher in the cold season, whereas that of isopods, decapods, chironomids and fish increased in the warm season. In general, larger specimens consumed larger prey, with an increase in the occurrence of isopods, decapods and fish. An analysis of trophic niche breadth defined G. cobitis as generalist, G. bucchichi as opportunist and S. porcus as specialist, whereas the values obtained for the other species did not indicate a clearly defined strategy. Low diet overlap values and the segregation observed in several analyses indicated an adequate distribution of resources.