Nueva defensa de tesina del Máster de Ecología Marina en el COB

La alumna del Máster de Ecología Marina de la UIB, Mª Teresa Farriols, defiende su tesina en el Centro Oceanográfico de Baleares

Mª Teresa Farriols, alumna del Máster de Ecología Marina de la UIB, presentó la memoria en el salón de actos del Centro Oceanográfico de Baleares el pasado martes 13 de noviembre.

Farriols ha realizado el período de prácticas del máster de Ecología Marina de la Universitat de les Illes Balears (UIB) en las dependencias del COB en virtud del Convenio firmado entre el IEO y la UIB de prácticas en empresas e instituciones para estudiantes de estudios oficiales de postgrado (másteres y doctorados). La tesina ha sido dirigida por el Dr. Enric Massutí, investigador del COB. Estuvieron presentes en el tribunal el director del Máster, el Dr. Gabriel Moyà y la Dra. Beatriz Guijarro.

La memoria ha versado sobre el estudio de los principales parámetros biológicos y el análisis demográfico de tríglidos, serranos y arañas, especies de peces que suponen una importante captura accidental en la pesquería de arrastre de la plataforma continental de las Islas Baleares y que constituyen una parte importante de la categoría de pescado mezclado comercializado como "morralla", con desembarques anuales promedio de 143 toneladas en la última década.

Resúmen de la tesina:

• Population dynamics and explotation of four by-catch nekton-benthic species in the bottom trawl fishery of the Balearic Islands (western Mediterranean), Mª Teresa Farriols (2012).

  The teleosts Chelidonichthys cuculus (Linnaeus, 1758) (Pisces: Triglidae), Trigloporus lastoviza (Bonnaterre, 1788) (Pisces: Triglidae), Serranus cabrilla (Linnaeus, 1758) (Pisces: Serranidae) and Trachinus draco (Linnaeus, 1758) (Pisces: Trachinidae), are important by-catch species in the bottom trawl fishery developed along the continental shelf off the Balearic Islands (western Mediterranean). They constitute an important fraction of the mixed fish category commercialized as “Morralla”, with annual landings averaging 143 tons in the last decade. The main biological parameters and a demographic analysis of these species are presented in this study. The length-weight relationships, the growth parameters of the Von Bertalanffy equation, the spawning season, the length at first maturity, and the natural mortality of these species, as well as their bathymetric distribution, abundance and length frequency estimated in previous Master’s Degree projects reports (Camps, 2009; Seda, 2009; Cánovas, 2010) have been compiled, reviewed, completed with new data, and re-calculated. Samples and data used come from the monthly monitoring of the bottom trawl fishery (2008-2010) and the annual MEDITS surveys in the study area (2001-2011), developed within the Data Collection Framework of the European Commission. Based on a steady state assumption, three years pseudo-cohorts (2008-2010) were created for each species by using catch data and fish length frequencies obtained by observers on board, and the annual official landings. Virtual Population Analysis (VPA) and Yield per Recruit (Y/R) models were carried out on these pseudo-cohorts using the estimated biological parameters in order to assess the exploitation level of the species. The state of the populations were also analyzed using fishery independent indicators, based on MEDITS surveys data, within the context of the Marine Strategy Framework Directive, such as the distribution range, the Conservation Status of Fish and the evolution of the abundance and biomass of the populations. The results can contribute to the improvement of the biological knowledge of fish species, poorly studied in the western Mediterranean, and the assessment and management of the bottom trawl fishery in the area.