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Santiago de Compostela, Spain

Rodriguez-Cabello C.,Spanish Institute of Oceanography | Perez M.,Spanish Institute of Oceanography | Banon R.,Servizo de Planificacion
Journal of Applied Ichthyology | Year: 2014

The aim of this study was to identify some of the Apristurus species by combining morphometric and genetic tools. Several specimens of the genus Apristurus were caught on the Galicia Bank Seamount (NE Atlantic), between 1460 and 1809 m depths, during a multidisciplinary survey carried out in 2011 within the framework of the INDEMARES Project. Morphometric and genetic analyses were conducted to aid the identification of the specimens collected. A total of 20 specimens were identified, of which 18 corresponded to Apristurus aphyodes (Nakaya and Stehmann, 1998), one to A. profundorum (Goode and Bean, 1896) and one to A. melanoasper Iglesias, Nakaya&Stehmann, 2004. Genetic results based on the mtDNA COI sequences (682-690 bp fragment of the COI gene) support the identification of A. profundorum and A. melanoasper, with a bootstrap of 99 and 96%, respectively. The identification of A. aphyodes was also performed using a 499 bp fragment of the 16S mitochondrial gene. These are the first records of the Apristurus species from Galician waters, which extends their known area of distribution and provides more information on different biological and ecological aspects of this complex taxonomic group. © 2014 Blackwell Verlag GmbH.

Villegas-Rios D.,CSIC - Institute of Marine Research | Villegas-Rios D.,Norwegian Institute of Marine Research | Alos J.,Leibniz Institute of Freshwater Ecology and Inland Fisheries | Palmer M.,CSIC - Mediterranean Institute for Advanced Studies | And 4 more authors.
Marine Ecology Progress Series | Year: 2014

Catchability, a key parameter in stock assessment, is often considered constant in time and space. However, when fishing with passive gears like traps or gillnets, fish behavior determines the odds of encounter with the fishers and thus catchability. Few studies have presented comprehensive empirical evidence of the link between behavior measured in the wild and catchability from a life-history strategy perspective. Here, a suite of different variables, including environmental cues, physiological states, fish activity, home range and catchability, were modeled using a sinusoidal function to describe their seasonality over the year and the degree of coupling among them in a sedentary coastal fish (Labrus bergylta). All the variables except the home range size showed a significant variation over the year, following a sinusoidal pattern. The models showed a tight match between the seasonality of catchability and fish activity, with high values of both variables occurring in late spring to early summer, when the highest levels of feeding and the period of reproductive inactivity occurred. Lower catchability values were predicted in late autumn to early winter, coinciding with the spawning season and the associated reduced activity. This integrative research shows that the spatio-temporal dimension of fish life-history strategy has a key role in shaping catchability even in highly sedentary species. Time-varying catchability needs to be incorporated into stock assessment models that aim to accurately describe fish population health and to estimate abundance indices. © Inter-Research 2014.

Alonso-Fernandez A.,CSIC - Institute of Marine Research | Otero J.,CSIC - Institute of Marine Research | Villegas-Rios D.,CSIC - Institute of Marine Research | Villegas-Rios D.,Norwegian Institute of Marine Research | Banon R.,Servizo de Planificacion
Marine Ecology Progress Series | Year: 2014

Fish body size is a key life history trait that influences population dynamics. Individual growth and size distribution are generally affected by both intrinsic and extrinsic factors. However, the drivers of body size changes are still poorly understood. The NW Iberian Peninsula is one of the most important fishing regions in Europe, where there is a special emphasis on artisanal fisheries. Despite the large contribution of small-scale fisheries to local communities, there is a lack of knowledge of the biotic and abiotic factors influencing the performance of coastal key species. In this study, we analyzed spatio-temporal changes in body size of Pollachius pollachius at the population level in response to a set of intrinsic and extrinsic factors. Generalized additive mixed-effects models were fit to a data set of ∼11000 records of individual body size of catch sampled by onboard observers during the last 13 yr in a complex multi-gear artisanal fishing fleet. Pollack body size showed strong spatio-temporal patterns, with an inshore-offshore geographic gradient where smaller fish were associated with shallower waters. Moreover, body size displayed a seasonal cycle, with larger individuals occurring mainly in winter months. This seasonality matches the annual reproductive cycle of the species. In addition, body size was affected by the interaction between population density and the temperature experienced by fish the year pre ceding the catch, with smaller individuals occurring at elevated temperatures and higher densities. © Inter-Research 2014.

Banon R.,Servizo de Planificacion | Arronte J.C.,C.O. de Santander | Barros-Garcia D.,University of Vigo | Vazquez-Dorado S.,University of Vigo | De Carlos A.,University of Vigo
Zootaxa | Year: 2013

From 2009 to 2011 eleven specimens belonging to four bathygadid species of the family Bathygadidae were captured in two different locations in the northern waters of Spain. The morphometric measurements and meristic characters of these specimens are given. The specimens were identified as belonging to the genera Gadomus Regan, 1903, and Bathygadus Günther, 1878, including the following species: Gadomus dispar (Vaillant, 1888), Gadomus longifilis (Goode & Bean, 1885), Gadomus arcuatus (Goode & Bean, 1886) and Bathygadus melanobranchus Vaillant, 1888. As a result, a new northern limit of distribution of G. arcuatus from the northeastern Atlantic is reported. The first molecular identification and genetic interrelationships of Bathygadidae species, based on the mitochondrial COI nucleotide sequences -DNA bar-codes- is reported. Sequences corresponding to specimens from the same species were identical and the overall mean ge-netic diversity (uncorrected p-distance) was 0.096 ± 0.008. Based on a morphological and meristic examination of the specimens, as well as on the available literature, an updated key of the members of the family Bathygadidae from the north-eastern Atlantic Ocean is provided. Copyright © 2013 Magnolia Press.

Banon R.,Servizo de Planificacion | Arronte J.C.,C.O. de Santander | Vazquez-Dorado S.,University of Vigo | Del Rio J.L.,C.O. de Vigo | de Carlos A.,University of Vigo
Molecular Ecology Resources | Year: 2013

DNA sequences of cytochrome c oxidase I gene (COI) from Lepidion spp. were employed to test the efficiency of species identification. A sample of 32 individuals from five Lepidion species was sequenced and combined with 26 sequences from other BOLD projects. As a result, 58 Lepidion DNA sequences of the COI gene belonging to eight of the nine recognized Lepidion species were analysed. Sequences were aligned and formed seven clades in a Bayesian phylogenetic tree, where Lepidion lepidion and Lepidion eques grouped jointly. The Kimura 2-parameter genetic distances, among congeners were, on average, 4.28%, 16 times greater than among conspecifics (0.27%). The main diagnostic meristic data of Lepidion spp. were compiled and a detailed morphological revision of the congeneric species L. eques and L. lepidion was made. The eye diameter was significantly different between L. eques and L. lepidion (P < 0.001). The number of anal fin rays ranged from 45 to 51 in L. lepidion and from 47 to 54 in L. eques, but no significant differences were obtained in the mean values of this variable (P = 0.07). According to the morphological and genetic analyses, the results strongly suggest that the Mediterranean codling L. lepidion and the North Atlantic codling L. eques are conspecific, making L. eques a junior synonym of L. lepidion. © 2012 Blackwell Publishing Ltd.

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