Identification guide for cephalopod paralarvae from the Mediterranean Sea

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Effects of fishing restrictions on the abundance, size structure and mortality rate of a western Mediterranean population of Scorpaena scrofa (Linnaeus, 1758)

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Trophic interactions among grouper (Epinephelus marginatus), octopus (Octopus vulgaris) and red lobster (Palinurus elephas) in the Western Mediterranean

In the present paper a first evaluation of the trophic interactions between grouper, octopus and spiny red lobster in the western Mediterranean is presented. The efficiency of octopus preying on lobsters is also estimated from trap catches. Grouper and octopus base their diet on the same major taxonomic groups and this is reflected in the values of diet overlap. Trophic diversity of grouper and octopus is also very similar. The estimation of the octopus efficiency preying on lobsters shows that 23.5% of the attacks are successfulPublicado

The use of Artificial Neural Networks (ANNs) in aquatic ecology

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Life-history, ecology and fishery of Sepia officinalis in the western Mediterranean

Cephalopods constitute important resources for different Mediterranean fisheries such as trawl, artisanal and recreational fleets. Cuttlefish (Sepia officinalis) has been caught there from ancient times on and holds an important seasonal artisanal fishery in the Balearic Islands (western Mediterranean). This fishery takes advantage of the reproductive migration to coastal waters of large, mature individuals, even though the species is also taken by bottom trawlers throughout the year. In this study we used data from the following sources to analyze different aspects of cuttlefish biology, ecology and fishery in the western Mediterranean: 1) monthly biological and size samplings of individuals caught by artisanal boats (2007-08); 2) size samplings on board ofcommercial bottom trawlers (2001-11); 3) biological and size samplings on spring scientific surveys (2001-11); and 4) official fishery statistics from 1965 to the present. The main objectives of this study are twofold. First, use all this information to generate a comprehensive insight on the life cycle of this species linking ecology and life-history traits to seasonal fishery trends. Secondly, analyze interannual variations on landings and the relationship with different environmental parameters (e.g. moon, temperature, climatic indices). Biological (N=950 individuals) and size frequency samplings were used to estimate different species and population parameters such as length-weight relationships, sex- ratio, population structure and dynamics, gonadosomadic index and fecundity. The vast majority of individuals caught by the artisanal fishery between January and July were sexually mature, which confirms the reproductive migration to coastal waters during spring. The clear seasonal trend observed in cuttlefish landings also tallies with this migration, since catches show a marked peak in March-April. Although landings display a sawtooth like pattern from 1965 to 2011 with historical maximums in 1991 and 2005, there is a general increasing trend with time, especially from mid-1990

Informe de campaña MN2001

Informe de campaña de la campaña oceanográfica realizada a bordo del B/O Ramón Margalef en enero de 2020. La campaña se enmarca en el proyecto MOLA-MENORCA 2 continuación de un proyecto anterior igualmente amparado por el convenio de colaboración CAIB-IEO. Esta campaña en concreto es la continuación de los trabajos de adquisición diseñados para producir la primera cartografía completa de detalle de la plataforma insular de la isla de Menorca.IEO-Govern Illes Balear

Stock assessment of Mullus surmuletus from GFCM GSA-05 (Balearic Islands)

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Stock boundaries for fisheries assessment and management in the Mediterranean: the Balearic Islands as a case study

The stock concept plays a pivotal role in fisheries assessment and management. Stocks are defined according to biological, geographical, economic or socio-political factors. The General Fisheries Commission for the Mediterranean (GFCM) has established thirty management geographical sub-areas (GSAs) based on political and statistical considerations rather than biological or economic factors. Here, we present our view on the main biological and ecological aspects that should be considered for delineating different management units in the Mediterranean. We focus on the Balearic Islands (GSA05) as a case study highlighting its specificities compared to the adjacent coast of the Iberian Peninsula (GSA06), but the approach could be generalized to the problem of identifying stock boundaries in other areas. The work is based on published information from different marine disciplines such as geomorphology, ecology and fisheries, combined with the analysis of new data coming from official fishery statistics and scientific surveys. This approach avoids the important draw¬backs (inconclusive results, high costs) of other time-consuming techniques used in stock identification, such as genetics. According to the information presented, we conclude that GSA05 should be maintained as an individualized area for assess-ment and management purposes in the western MediterraneanPublicado

La importància del sector pesquer en la investigació oceanogràfica

Una gran part de les activitats científiques que es duen a terme per estudiar els mars i oceans no seria possible sense la col·laboració del sector pesquer. Poder disposar de dades biològiques o pesqueres obtingudes per la flota és bàsic i imprescindible per a molts dels estudis que duem a terme els biòlegs marins. La recollida d’aquestes dades es fa tant mitjançant embarcaments a bord de les distintes flotes, com a través del mostratge de les captures un cop desembarcades a la llotja per a la seva comercialització. En el nostre cas, sempre hem contat amb la col•laboració del sector pesquer per dur a terme la nostra feina dirigida a la investigació dels recursos i ecosistemes marins en aigües de Catalunya i les Illes Balears. En moltes ocasions, el sector ens ha sol•licitat informació sobre els estudis que realitzem a partir de les dades obtingudes amb la seva col•laboració. Això no sempre és tan senzill com sembla, donat que en la majoria de casos els treballs que duem a terme estan escrits en anglès i destinats a un públic especialitzat, de manera que poden resultar difícils d’assimilar pel públic en general. La falta de documentació de caire divulgatiu ha fet que, fins ara, no haguem pogut respondre de forma adequada als esmentats requeriments d’informació sobre els objectius i resultats del nostre treball. Això ens ha portat a escriure aquest llibret, el qual és un intent d’apropar la nostra feina a tota la gent del sector que, d’una manera o una altra, col•labora amb nosaltres i fa que aquesta feina sigui possible. En les següents pàgines trobareu informació sobre qui som, què fem i perquè ho fem. El nostre objectiu és que el llibret doni respostes a moltes de les qüestions que se’ns han plantejat des del sector i ajudi a donar a conèixer els treballs que duem a terme amb la seva col•laboració, amb la qual esperem poder seguir contant en el futurPublicad