Three small-scale fisheries based on the island of Majorca (NW Mediterranean)

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Disentangling the influence of fishing, demography and environment on population dynamics of Iberian Peninsula waters fish stocks

Overexploitation and climate change are increasingly causing unanticipated changes in marine ecosystems such as higher variability in fish recruitment or shifts in species dominance and distribution that alter the productivity of fish stocks. This study analyses how external and internal drivers influence population dynamics of hake (Merluccius merluccius), white anglerfish (Lophius piscatorius), four-spot megrim (Lepidorhombus boscii), and horse mackerel (Trachurus trachurus) of Iberian Peninsula waters of the Northeast Atlantic across different spatiotemporal scales. Available spawning stock biomass and recruitment have been used as biological data, whereas fishing mortality, demographic data as well as climatic and oceanographic data have been used as drivers. The obtained results indicate that population dynamics of these species are mainly driven by oceanographic variability at regional scale along with fishing pressure and demographic factors, while the impact of large-scale climate indices was minimal. The identified variables represent relevant oceanographic regional processes candidate to be potentially integrated into the stock assessment models and management procedures of these important fishery resource

An attempt to determine variability of RNA/DNA ratios during Dicentrarchus labrax larval development

RNA and DNA content of seabass (Dicentrarchus labra.x) larvae were determined from day 10 to day 60 after hatching in an aquaculture facility. Our results show a two-phase modulation of the RNA/DNA ratio throughout seabass larvae development. From day 10 after hatching there is an increase in the RNA/DNA ratio reaching maximal values at day 30 of age. Then, the RNA/DNA ratio decreased reaching minimal values at day 60 after hatching. These results are consistent with a high rate of protein synthesis during the first 30 days of seabass development compared with the rest of the developmental period studied. The results are compared with that of otolith growth carried out for the same species larvaeAPROXIMACIÓ A LA DETERMINACIÓ DE LA VARIABILITAT DE LA RELACIÓ DNA/RNA DURANT EL DESENVOLUPAMENT LARVAL DEL LLOBARRO Dicentrarchus labrax. S'ha determinat el contingut de DNA (àcid desoxiribonucleic) i de RNA (àcid ribonucleic) en larves de llobarro (Dicentrarchus labrax) d'edats compreses entre 10 i 60 dies de vida, procedents d'una planta de cultiu. Els resultats obtinguts mostren dues fases diferenciades de desenvolupament d'aquestes larves, basades en la relaci6 RNA/DNA avaluada. S'observa un augment de la proporci6 de RNNDNA des del dia 10 fins el dia 30 de vida, per a decréixer a continuació, trobant els valors mínims en les larves de 60 dies de vidaPublicado

Are pelagic cephalopods in the Mediterranean as abundant as suggests the stomach contents of their predators?

Final workshop IDEADOS: The wrapping up of the IDEADOS project, International Workshop on Environment, Ecosystems and Demersal Resources and fisheries, 14-16 November 2012, Palma de Mallorca, SpainPeer reviewe

A mesoscale index to describe the regional ocean circulation around the Balearic Islands

The formation of Western Mediterranean Intermediate Water (WIW) in the Gulf of Lions and its later presence in the Balearic Channels play a significant role in the regional circulation. The presence of WIW, given by the intermediate water temperatures in the Ibiza Channel, has been related to air temperture in the Gulf of Lions, providing a continuous and long index of regional circulatio