Paz B.,Instituto Investigaciones Marinas CSIC |
Paz B.,Spanish Institute of Oceanography |
Franco J.M.,Instituto Investigaciones Marinas CSIC |
Franco J.M.,Spanish Institute of Oceanography
Harmful Algae | Year: 2013
Yessotoxins (YTXs) production along the culture growth of three strains of the dinoflagellate Protoceratium reticulatum isolated from seawater of Galician Rias Baixas, Spain was investigated. Quantification and toxin profile determination in both cells and culture medium along the growth curve were performed by liquid chromatography-mass spectrometry (LC-MS3) analysis. The YTX profile was very similar among strains, the three algal strains produce mainly YTX and also some YTX analogs. Among the strains the maximum toxin production ranged between 416 and 576ngmL-1. This is the first report about YTX production by P. reticulatum isolated in Galician coast, NW Spain. © 2012 Elsevier B.V.
Contreras-Catala F.,National Polytechnic Institute of Mexico |
Sanchez-Velasco L.,National Polytechnic Institute of Mexico |
Beier E.,Research Center Cientifica Educacion Superior Of Ensenada |
Godinez V.M.,Research Center Cientifica Educacion Superior Of Ensenada |
And 2 more authors.
PLoS ONE | Year: 2016
Effects of geostrophic kinetic energy flux on the three-dimensional distribution of fish larvae of mesopelagic species (Vinciguerria lucetia, Diogenichthys laternatus, Benthosema panamense and Triphoturus mexicanus) in the southern Gulf of California during summer and fall seasons of stronger stratification were analyzed. The greatest larval abundance was found at sampling stations in geostrophic kinetic energy-poor areas (<7.5 J/m3), where the distribution of the dominant species tended to be stratified. Larvae of V. lucetia (average abundance of 318 larvae/10m2) and B. panamense (174 larvae/10m2) were mostly located in and above the pycnocline (typically ∼ 40 m depth). In contrast, larvae of D. laternatus (60 larvae/10m2) were mainly located in and below the pycnocline. On the other hand, in sampling stations from geostrophic kinetic energy-rich areas (> 21 J/m3), where mesoscale eddies were present, the larvae of the dominant species had low abundance and were spread more evenly through the water column, in spite of the water column stratification. For example, in a cyclonic eddy, V. lucetia larvae (34 larvae/10m2) extended their distribution to, at least, the limit of sampling 200 m depth below the pycnocline, while D. laternatus larvae (29 larvae/10m2) were found right up to the surface, both probably as a consequence mixing and secondary circulation in the eddy. Results showed that the level of the geostrophic kinetic energy flux affects the abundance and the three-dimensional distribution of mesopelagic fish larvae during the seasons of stronger stratification, indicating that areas with low geostrophic kinetic energy may be advantageous for feeding and development of mesopelagic fish larvae because of greater water column stability. © 2016 Contreras-Catala et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Perez-Camacho A.,Spanish Institute of Oceanography |
Labarta U.,Instituto Investigaciones Marinas CSIC |
Vinseiro V.,Instituto Investigaciones Marinas CSIC |
Fernandez-Reiriz M.J.,Instituto Investigaciones Marinas CSIC
Aquaculture | Year: 2013
Mussel raft culture as traditionally practiced in Galicia (Spain) represents an extreme case of aggregation, where culture density along growth ropes is maximized to achieve greater commercial yields. However, to maintain high growth rates during the entire cultivation period the initial density must be reduced through a process called "thinning-out" when rope weight increases by a factor of 10.In raft culture, the annual commercial cycle is superimposed on a production cycle that can last up to 18. months. For this reason, the thinned-out mussel ropes can only occupy 75% of the usable surface area of the raft. Additionally, the rope handling process has a pronounced impact on production costs, affecting both labor and material costs.With the objective of optimizing economic yields in mussel raft culture, we conducted a study to compare a new technique without thinning-out with the traditional method, and we evaluated the effect of density on mussel growth for both techniques.For this purpose, three different densities were prepared for the no thinning-out ropes (800n, 1000n and 1200n mussels/m), and the other three for the thinning-out ropes (400y, 500y and 600y mussels/m).At the end of the experiment, average length and average live weight for mussels cultured without thinning-out were significantly lower than values observed for mussels cultured with thinning-out. However, the no thinning-out technique did not result in a lower total biomass production.The technique without thinning-out has a production cycle of 12. months, which coincides with annual production. On the other hand, the culture with thinning-out technique has a 15-month cycle (seeding and thinning-out processes); thus annual production was 20% lower than total production. Under these conditions, production at the two highest densities (1000n and 1200n) was significantly higher than production at all densities with thinning-out.If we consider economic yield per raft per year, which also takes into account the higher price of mussels with increasing size, the difference between the two culture methods is smaller. Only the 1200n ropes still produced a higher economic yield than the 600y ropes. On the other hand, the shortening of the cultivation time and the elimination of the thinning-out reduce the production costs.In conclusion, the results obtained with the new culture technique without thinning-out at high seed densities enable substantial improvements in terms of biomass, economic yields, and operating costs for mussel production. © 2013 Elsevier B.V.
Leon-Chavez C.A.,National Autonomous University of Mexico |
Beier E.,Research Center Cientifica Educacion Superior Of Ensenada |
Sanchez-Velasco L.,CICIMAR IPN |
Barton E.D.,Instituto Investigaciones Marinas CSIC |
Godinez V.M.,Research Center Cientifica Educacion Superior Of Ensenada
Journal of Geophysical Research C: Oceans | Year: 2015
On the basis of five oceanographic cruises carried out in the Eastern Tropical Pacific off Mexico, relationships between the larval fish habitats (areas inhabited by larval fish assemblages) and the environmental circulation scales (mesoscale, seasonal, and interannual) were examined. Analysis of in situ data over a grid of hydrographic stations and oblique zooplankton hauls with bongo net (505 μm) was combined with orthogonal robust functions decomposition applied to altimetry anomalies obtained from satellite. During both cool (March and June) and warm (August and November) periods, Bray-Curtis dissimilarity Index defined three recurrent larval fish habitats which varied in species composition and extent as a function of the environmental scales. The variability of the Tropical larval fish habitat (characterized by high species richness, and dominated by Vinciguerria lucetia, Diogenichthys laternatus, and Diaphus pacificus) was associated with the seasonal changes. The Transitional-California Current larval fish habitat (dominated by V. lucetia and D. laternatus, with lower mean abundance and lower species richness than in the Tropical habitat) and Coastal-and-Upwelling larval fish habitat (dominated by Bregmaceros bathymaster) was associated mainly with mesoscale activity induced by eddies and with coastal upwelling. During February 2010, the Tropical larval fish habitat predominated offshore and the Transitional-California Current larval fish habitat was not present, which we attribute to the effect of El Niño conditions. Thus, the mesoscale, seasonal, and interannual environmental scales affect the composition and extension of larval fish habitats. Key Points: Variability of larval fish habitats in the Eastern Tropical Pacific Water masses and larval fish habitats in the Eastern Tropical Pacific ENSO influences in the larval fish habitats in the Eastern Tropical Pacific © 2015. American Geophysical Union. All Rights Reserved.
Ruiz-Ochoa M.,National University of Colombia |
Ruiz-Ochoa M.,University of Antioquia |
Beier E.,Research Center Cientifica |
Bernal G.,National University of Colombia |
Barton E.D.,Instituto Investigaciones Marinas CSIC
Deep-Sea Research Part I: Oceanographic Research Papers | Year: 2012
Daily sea surface temperature (SST) data from the Advanced Very High Resolution Radiometer (AVHRR) database with ~4km of spatial resolution were analyzed for the period 1985-2009 in the Colombian Basin using harmonic and empirical orthogonal function (EOF) analysis. The data were compared with observational records in the Rosario Island National Park at 10m depth (T 10) from March 2003 to August 2005. SST values were higher than T 10 from June to October (rainy season), but similar from December to February (dry season); both data sets have similar coefficient of variation. The mean SST distribution varies spatially, with minimum SST values in the coastal zone of La Guajira Peninsula and maximum values in the Darien and Mosquitos Gulfs. The seasonal variability explains up to 75% of the total variability in La Guajira, a high value compared with 40% in the Mosquitos Gulf. The most important feature of the splitting of SST variation into annual and semiannual harmonics in La Guajira is the relationship between their amplitudes. These are of the same order, which is not common in other ocean zones, where the semiannual component is only a small fraction of the annual dominated by the solar warming. The river water discharge, highest from August to November, produces low density surface water, reduces vertical mixing and limits the absorption of solar radiation to a thin surface layer, explaining the discrepancy between SST and T 10 in the rainy season. The decomposition of the SST in EOFs indicated that the dominant mode of the basin is a uniform interannual variation in phase with the North Tropical Atlantic Index. The second mode, representing the variability of the Guajira upwelling, covaried strongly with the second mode of wind stress curl. The third mode reflected the role of the vertical atmospheric circulation cell associated with the Caribbean Low Level Jet off Central America. © 2012 Elsevier Ltd.