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Revista de Biología Marina y Oceanografía
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ISSN (Print) 0717-3326 - ISSN (Online) 0718-1957
Published by SciELO

[688 journals]

Comparison of thermal fronts frequency and permanence using data of
different spatial dimensions and satellite images resolution in California
Current southern region
- Abstract: Resumen: Se evaluó la mejor dimensión de la escala espacial (dimensión de cuadrantes) y resolución espacial de imágenes (1 y 4 km), con respecto a la frecuencia y permanencia de frentes oceánicos de temperatura que caracterizan la variabilidad estacional e interanual en la región sur del Sistema de la Corriente de California durante 2006-2010, a partir del análisis de imágenes diarias de temperatura superficial del mar (“Multi-scale Ultra-high Resolution” de 1 km y “Advanced Very High Resolution Radiometer” de 4 km de resolución de píxel). La identificación de los frentes oceánicos de temperatura se realizó mediante el algoritmo de detección de borde (SIED, por sus siglas en inglés). Para identificar la mejor distribución de los frentes se compararon diferentes dimensiones de cuadrantes (0,5°, 1,0° y 2,0° latitud y longitud geográfica). El cuadrante de 1,0° resultó ser el más adecuado por presentar una menor dispersión de la frecuencia de frentes y un mayor número de observaciones, aunado a las imágenes de alta resolución (1 km) que permitieron detectar un mayor número de estructuras de mesoescala de la variabilidad estacional e interanual de la dinámica oceánica de la porción sur de la Corriente de California.Abstract: The best dimension of spatial scale (quadrant dimension) and images resolution (1 and 4 km) were evaluated, with respect to frequency and permanence of oceanic thermal fronts that characterize seasonal and interannual variability of the California Current System during 2006-2010, from the analysis of daily images of sea surface temperature (1 km Ultra High-Resolution Multi-Scale and Advance Very High-Resolution Radiometer resolution of 4 km pixel resolution). Fronts identification was performed using Single Edge Detection (SIED) algorithm and to identify the best distribution in the area different quadrant dimensions were compared (0.5°, 1.0° and 2.0° geographical latitude and longitude). 1.0° quadrant turned out to be the most suitable because it presented a lower dispersion of front frequency and a greater number of observations. Together with high-resolution images (1 km) they allowed to detect a greater number of mesoscale structures, which identifies seasonal and year-to-year variability of ocean dynamics in California Current southern portion.
Effect of irradiance and temperature on Chondracanthus chamissoi
sporophytes
- Abstract: Resumen: La macroalga Chondracanthus chamissoi, conocida comúnmente como "yuyo" o “chicorea de mar”, ha adquirido una gran importancia económica en los últimos años debido a su potencial como recurso acuícola en Perú y Chile. Por esta razón, es necesario conocer los factores que afectan su cultivo. Con el objetivo de determinar el efecto de la irradiancia y la temperatura sobre el asentamiento y crecimiento de esporofitos de C. chamissoi, se sometieron carposporas recién liberadas a dos niveles de irradiancia (35 y 70 µmol m-2 s-1) y tres temperaturas (18, 20 y 22 ºC) durante 6 semanas. Se cuantificó el número de carposporas asentadas a los 7 días de iniciada la inoculación y se midieron los microtalos formados a partir del día 22. Los resultados mostraron que el mayor asentamiento fue a 35 µmol m-2s-1 y 22 ºC, con 209,33 ± 24,58 esporofitos por cm2. Las menores densidades se obtuvieron en los tratamientos de 18 y 20 ºC a 35 µmol m-2s-1, con 74,7 ± 45,5 y 57,0 ± 37,6 esporofitos por cm2, respectivamente. La mayor tasa de crecimiento específico (TCE) se logró a 70 µmol m-2s-1 (18 ºC), con 8,3% d-1, seguida de 70 µmol m-2s-1 (22 ºC), y 70 µmol m-2s-1 (20 ºC) con 8,2 y 8,1% d-1, respectivamente. En conclusión, los esporofitos de C. chamissoi se pueden desarrollar a mayor velocidad a una irradiancia de 70 µmol m-2s-1, teniendo en cuenta que al aumentar la temperatura se puede generar una disminución en la tasa de crecimiento.Abstract: Chondracanthus chamissoi, commonly known as "yuyo" or "sea chicory", has acquired great economic importance in recent years due to its potential as an aquaculture resource in Peru and Chile. For this reason, it is necessary to know the factors that affect its cultivation. With the aim of determining the effect of irradiance and temperature on the settlement and growth of C. chamissoi sporophytes, newly released carpospores were subjected to two levels of irradiance (35 and 70 µmol m-2 s-1) and three temperatures (18, 20 and 22 ºC) for 6 weeks. The number of settled carpospores was quantified 7 days after the start of inoculation and microthalli formed were measured from day 22. Results showed that the highest settlement occurred at 35 µmol m-2s-1 and 22 ºC, with 209.33 ± 24.58 sporophytes per cm2. The lowest densities were obtained in the treatments of 18 and 20 ºC at 35 µmol m-2s-1, with 74.7 ± 45.5 and 57.0 ± 37.6 sporophytes per cm2, respectively. The highest specific growth rate (SGR) was achieved at 70 µmol m-2s-1 (18 ºC), with 8.3% d-1, followed by 70 µmol m-2s-1 (22 ºC), 70 µmol m-2s-1 (20 ºC) with 8.2 and 8.1% d-1, respectively. In conclusion, sporophytes of C. chamissoi can develop at a higher speed at an irradiance of 70 µmol m-2s-1, considering that increasing the temperature can generate a decrease in the growth rate.
Taxonomic diversity of the marine Amphipods (Crustacea, Peracarida) of
Cuba
- Abstract: Resumen: Los anfípodos están presentes en casi todos los ecosistemas marinos y estuarinos del mundo. En Cuba, es uno de los grupos de invertebrados mejor conocidos en cuanto a su sistemática. Sin embargo, un inventario completo de especies y su diversidad taxonómica, así como la incidencia de los hábitats en los cuales se desarrollan estos organismos, aún no han sido estudiados. En el presente trabajo se presentó la totalidad de las especies inventariadas hasta la fecha. Se analizó además la diversidad taxonómica del grupo y la posible incidencia del hábitat sobre ésta. Se conformó una base de datos a partir de las listas de especies de anfípodos publicadas en la literatura científica, así como donaciones de especímenes recolectados en varias zonas de la plataforma marina por estudiantes y colegas, conteniendo datos de presencia y distribución de las especies. La verificación de logro para obtener el inventario completo se obtuvo mediante curvas de acumulación de especies, a partir de estimadores no paramétricos. La diversidad taxonómica se estimó con los índices de distinción taxonómica promedio (Delta+) y su variación (Lambda+). Hasta la fecha, se han registrado 200 especies de anfípodos marinos, que se distribuyeron en cuatro subórdenes, 13 parvordenes, 27 superfamilias, 57 familias y 109 géneros, para una totalidad del inventario del 67,2%. La distinción taxonómica promedio para la plataforma marina cubana fue de 77,6 y su variación de 204. Los hábitats no afectaron a la distinción taxonómica promedio, pero si a su variación. Se recomienda continuar los estudios sistemáticos del grupo, y profundizar en las investigaciones de su ecología.Abstract: Amphipods are present in almost all marine and estuarine ecosystems around the world. In Cuba, the members of this group of invertebrates have been highly studied in terms of their systematics. However, the total species inventory and its taxonomic diversity, as well as the incidence of the habitats in which these organisms develop have not yet been surveyed. The complete inventory of species to date is presented for the first time and the taxonomic diversity of the group is analyzed. The possible impact of habitat on the taxonomic diversity of these organisms was also evaluated. A database was created from lists of amphipod species published in the scientific literature, as well as donations of specimens collected in various areas of the marine shelf by students and colleagues, containing species occurrence and distribution data. The completeness of the inventory was assured by species accumulation curves from non-parametric estimators. Taxonomic diversity was estimated with the average taxonomic distinctiveness indices (Delta+) and its variation (Lambda+). To date, 200 species of marine amphipods have been registered, which were distributed in four suborders, 13 parvordenes, 27 superfamilies, 57 families and 109 genera, with a total inventory of 67.2%. Average taxonomic distinctiveness for the Cuban marine shelf was 77.6 and the variation was 204. Habitats did not affect the average taxonomic distinctiveness, but it did affect its variation. It is recommended to continue the systematic studies of the group, and go deeper in investigations of its ecology.
Community assemblages of migratory larids (Charadriiformes: Laridae) in
southwestern Gulf of Mexico
- Abstract: Resumen: Los representantes de la familia Laridae tienen un rol importante en la ecología funcional de los ambientes marinos y costeros, por lo que han sido descritos como bioindicadores de la ictiofauna, sin embargo, el conocimiento sobre estas aves en el suroeste del golfo de México es limitado. El objetivo del presente estudio fue estudiar los ensambles y patrones migratorios de la familia Laridae en la línea costera de la playa Barra Norte, Estado de Veracruz, suroeste del golfo de México. Durante la temporada migratoria invernal 2014-2015 se realizaron tres muestreos mensuales a través de transectos lineales de 1 km x 600 m. Los ensambles se abordaron a través de índices de diversidad (equidad de Pielou, dominancia de Simpson y de diversidad verdadera) y especies dominantes (caracterizadas por un análisis de similitud porcentual). Con un análisis de correspondencia canónico parcial se estudió su migración. Se registraron 3.314 organismos agrupados en 14 especies. La equidad fue más alta en abril y la dominancia en febrero. Las especies dominantes fueron Leucophaeus atricilla, Thalasseus maximus, T. acuflavidus e Hydroprogne caspia. Se encontraron tres patrones migratorios que coinciden con las temporadas de lluvias, nortes y secas. Cada patrón contiene particulares ensambles de especies. El primer patrón ocurre de agosto a octubre 2014 (Sterna hirundo, T. acuflavidus y Chlidonias niger), el segundo de noviembre 2014 a febrero 2015 (Larus delawarensis, L. californicus, L. argentatus smithsonianus, L. atricilla, H. caspia y Rissa tridactyla), y el último abarca abril y mayo 2015 (Rynchops niger, Sternula antillarum y L. pipixcan). Los resultados establecen que el ensamblaje comunitario de los láridos se compone de un patrón migratorio múltiple.Abstract: Individuals of Laridae family play an important role in functional ecology of marine and coastal environments, and have been described as bioindicators of ichthyofauna, however, knowledge about these birds in southwestern Gulf of Mexico is limited. The objective of the present study was to study Laridae family assemblages and migratory patterns along Barra Norte beach coastline, Veracruz State, southwestern Gulf of Mexico. During 2014-2015 winter migratory season, three monthly samplings were conducted along 1 km x 600 m line transects. The assemblages were approached through diversity indices (Pielou's equity, Simpson's dominance and true diversity) and dominant species (characterized by a percentage similarity analysis). Migration was studied with a partial canonical correspondence analysis. A total of 3,314 organisms grouped into 14 species were recorded. Equity was highest in April and dominance in February. The dominant species were Leucophaeus atricilla, Thalasseus maximus, T. acuflavidus and Hydroprogne caspia. Three migratory patterns were found and coincide with the rainy, northerly and dry seasons. Each pattern contains particular species assemblages. The first pattern occurs from August to October 2014 (Sterna hirundo, T. acuflavidus and Chlidonias niger), the second from November 2014 to February 2015 (Larus delawarensis, L. californicus, L. argentatus smithsonianus, L. atricilla, H. caspia and Rissa trydactila) and the last one covers April and May 2015 (Rynchops niger, Sternula antillarum and L. pipixcan). Results establish that larids community assemblage is composed of a multiple migratory pattern.
Evaluation of Cuban oyster resource status (Crassostrea spp.) and
reference points for its management
- Abstract: Abstract: Oyster Crassostrea spp. is the bivalve mollusk with the largest commercial volume in Cuba. Populations should be assessed for their management and conservation, which has been performed but with different methodologies and only in certain localities, making it difficult to evaluate and compare between periods and regions. Therefore, current state of the resource was to be determined according to maximum sustainable yield (MSY), biomass for the maximum sustainable yield (BMSY), and corresponding fishing mortality rate (FMSY). Catch Maximum Sustainable Yield (CMSY) model was applied with Monte Carlo method, resource biomass and exploitation were evaluated for northwestern (NW), northeastern (NE), southeastern (SE), and southwestern (SW) regions of the insular platform, as well as for periods (1960-1991 and 1992-2020). From 1992-2020, a 50% reduction in oyster landings was recorded when compared with 1960-1991 period, which was reflected in population indicators according to estimated fishery reference points. Based on applied model and method, current oyster fishery management is perceived as unsustainable with stock depletion and overfishing in NW, NE, and SW regions. Cuban SE region shows a more favorable status. Oyster farming should increase to obtain higher production and broodstock biomass to decrease fishing effort on wild populations.Resumen: En Cuba, la ostra Crassostrea spp. es el molusco bivalvo de mayor volumen comercial. La evaluación de sus poblaciones es necesaria para su manejo y conservación, pero se ha realizado con diferentes metodologías y solo en localidades puntuales, lo que dificulta su evaluación y comparación entre periodos y regiones. Por lo tanto, se determinó el estado actual del recurso según el rendimiento máximo sostenible (MSY), biomasa para el rendimiento máximo sostenible (BMSY) y la tasa de mortalidad por la pesca (FMSY) correspondiente. Se aplicó el modelo CMSY con método de Monte Carlo, y se evaluó la biomasa y la explotación del recurso para las regiones noroeste (NW), noreste (NE), sureste (SE) y suroeste (SW) de la plataforma insular, así como por periodos (1960-1991 y 1992-2020). Durante 1992-2020 se registró una reducción del 50% en los desembarques de ostras respecto al periodo 1960-1991, lo que se reflejó en los indicadores poblacionales según los puntos de referencia evaluados. De acuerdo con el modelo y método aplicados, la gestión pesquera actual de la ostra se percibe no-sostenible, con agotamiento del stock y sobrepesca en las regiones NW, NE y SW. La región SE del país presenta un estado más favorable. Se sugiere incrementar la ostricultura para obtener mayor producción y biomasa de reproductores para disminuir el esfuerzo de pesca sobre las poblaciones silvestres.
Description of the dermal denticles on pre-pelvic claspers of the
Cockfish, Callorhinchus callorynchus (Holocephali: Callorhinchidae), from
Coquimbo, Chile
- Abstract: Abstract: Chimaeras or Ghost sharks (Subclass Holocepahli) have sexual structures called pre-pelvic claspers, and these structures are covered by dermal denticles. In this study, dermal denticles present in pre-pelvic claspers of the Cockfish, Callorhinchus callorynchus, were described in order to compare them with those of other known species of this subclass. Pre-pelvic claspers of 22 specimens were removed for further examination. Dermal denticles on the flat surface of pre-pelvic claspers were different when examining their size, shape, and number of cusps. Dermal denticles were classified as type A (three cusps), B (four cusps), C (five cusps), D (six cusps) and E (eight cusps). Dermal denticles with fewer cusps were located near the center, whereas those with more cusps were located towards the periphery. All types of dermal denticles were found in the largest individuals (> 40 cm length). Possible functions of the dermal denticles and the pre-pelvic clasper in the reproductive activity of this species are suggested.
Melanism records in Sebastes oculatus (Perciformes, Scorpaenoidei:
Sebastidae) in the northern coast of Chile
- Abstract: Abstract: Melanism is the presence of an excess of dark pigmentation in an animal, which causes a total or partial blackening of the skin. In fish, melanosis has been reported for a few species, indicating that it is not a common aspect and that it more frequently affects limnic species. The capture of a Sebastes oculatus female specimen, with complete melanism, is reported. The individual was captured by hand line, in the town of Isla Pájaro II, northern Chile. Its standard length is 31.5 cm and its total weight is 993 g. The general coloration of the body is dark gray. The fins do not have the orange hue characteristic of the species at their ends. The melanic condition in S. oculatus is very rare, it is the second time that it has been reported for this species, where the expression of a dark color would be beneficial for specimens that inhabit bottoms with little vegetation and between cracks.

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