Showing papers in "Revista De Biologia Marina Y Oceanografia in 2018"
TL;DR: The results show that the use of the microalga Chlorella vulgaris for the absorption of nutrients and growth in wastewater is feasible, which opens up encouraging perspectives for its application in purification processes in the fish farming activity or another industry that generates effluents with these characteristics.
Abstract: Growth of microalgae Chlorella vulgaris and its efficiency in dissolved nutrients removal from effluent generated by yellowtail amberjack hatchery production were studied under laboratory scale conditions. This research evaluated indoor and outdoor conditions during 8 days, using filtered and UV light disinfected effluent, inoculated with an initial concentration of 2.06·10 6 ± 4.16·10 3 cells mL -1 of Chlorella vulgaris . In the determination of the growth and removal of nutrients, 12 transparent cylindrical-conical ponds with a capacity of 50 L were used. Three ponds were used for each experimental condition, indoor (3) and outdoor (3), with effluent water from the dorado culture, the remaining six ponds were controls using 1μm filtered seawater, disinfected and enriched with general culture medium F/2, in indoor (3) and outdoor (3), respectively. The result of growth under indoor condition reached a maximum value of 4.17·10 6 ± 7.57·10 5 cells mL -1 after 6 days. Similar growth was achieved in control tanks 4.75·10 6 ± 2.29·10 5 cells mL -1 , whereas in outdoor experimental condition the maximum growth obtained was 2.81·10 6 ± 2.69·10 5 cells mL -1 reached on day 2, compared with controls that showed a maximum growth of 1.83·10 7 ± 2.29·10 5 cells mL -1 . The best nutrient removal results recorded as nitrite removal were values of 91.67 and 88.41% (indoor and outdoor conditions, respectively). Nitrate removed reach a 57.47% (indoor) and 29.31% (outdoor) and a similar ammonia removal of 42.22% for both experimental conditions. Finally, high phosphate removal of 65.78% (indoor) and 75.78% (outdoor) were observed. The results show that the use of the microalga Chlorella vulgaris for the absorption of nutrients and growth in wastewater is feasible, which opens up encouraging perspectives for its application in purification processes in the fish farming activity or another industry that generates effluents with these characteristics.
10 citations
TL;DR: The results of the study suggest that Streptomyces sp.
Abstract: A total of 72 morphologically different actinomycetes isolates were isolated from samples collected at different regions of Vellore, Tamil Nadu, India and screened for its antibacterial activity against fish and shellfish pathogens. All actinomycetes isolates were screened for antibacterial activity by cross streak method against the selected fish and shellfish bacterial pathogens including Aeromonas caviae, Aeromonas hydroplila, Edwardsiella tarda, Vibrio anguillarum and Vibrio harveyi . Secondary screening of antagonistic isolates by well diffusion method leads to the identification of potential isolate. Culture conditions for the potential isolate were optimized for maximal growth and yield of the ethyl acetate (EA) crude extract. The potential isolate was characterized by molecular taxonomy and phylogeny and identified as Streptomyces species and named as Streptomyces sp. VITNK9. The 16S rDNA nucleotide sequence was searched through the GenBank database and showed 83% similarity to Streptomyces vinaceusdrappus. The EA extract prepared from Streptomyces sp. VITNK9 showed moderate antagonistic activity accessed by the formation of zone of growth inhibition against, Aeromonas caviae (15.33 mm) , Aeromonas hydrophila (17.66 mm) , Edwardsiella tarda (18.33 mm) , Vibrio anguillarum (14.33 mm) and Vibrio harveyi (14.33 mm). The MIC value of EA extract was ranged between 0.03-0.125 mg mL-1. The GC-MS spectrum of the ethyl acetate extract revealed the presence of two major compounds, pyrrolo [1,2-A] pyrazine- 1,4-Dione (56.67%) and Hexahydro-3-(2-Methylpropyl) (27.91%), respectively. The results of the study suggest that Streptomyces sp. VITNK9 is a potential source for antagonistic secondary metabolites against fish and shellfish bacterial pathogens.
10 citations
TL;DR: In this paper, plankton samples were collected through bongo net oblique tows in 40 stations from onboard a bio-oceanographic cruise took place in inner fjords of southern Chile (47° to 51°S).
Abstract: Chilean Patagonian fjords are characterized by strong stratification and chemical gradients which influence the ichthyoplankton distribution and abundance. Plankton samples were collected through bongo net oblique tows in 40 stations from onboard a bio-oceanographic cruise took place in inner fjords of southern Chile (47° to 51°S). Water column physical data were obtained with a conductivity-temperature-depth profiler (CTD) and turbidity was measured with a portable turbidimeter from 0 to 100 m depth. Stations were distributed by three zones: oceanic, channels and continental waters. A total of 1424 larvae were collected, representing 21 families. Dominant taxa were Maurolicus parvipinnis (31%), Sebastes oculatus (12%), Merluccius australis (11%), Lampanyctodes hectoris (10%), and Bathylagichthys parini (8%). Most of the environmental variability was determined by salinity, mainly in the area where continental waters are discharged. The water column in the oceanic zone presented mixed waters dominated by the myctophid L. hectoris and the sternoptychid M. parvipinnis . No significant effect of turbidity gradients on larval fish assemblages was evident during spring. The channel zone was both more saline, and density stratified with less turbidity, and lower abundance of species. Two ichthyoplanktonic assemblages were evident, one living in oceanic waters, and the other from channels and inner zones.
8 citations
TL;DR: Guafo Island is an important breeding, shelter, and feeding site for marine mammals in Chile as mentioned in this paper, and the growing anthropogenic pressure on this ecosystem emphasizes the importance of formal protection of this island as a priority site for Marine conservation in the Northern Patagonia of Chile.
Abstract: The chiloense marine ecoregion, at the Northern Chilean Patagonia, has been considered a hotspot of marine mammal diversity, yet little is known regarding specific sites used by these species for reproduction, nursing, refuge, and foraging. This information is critical for proper spatial ecosystem planning and conservation of marine resources. In the austral summers of 2004 through 2008, and from 2012 to 2017, the presence, distribution, and behavior of 13 species of marine mammals was recorded at Guafo Island, an oceanic island located in the center of the chiloense ecoregion. Guafo Island is an important reproductive and feeding site for South American fur seals ( Arctocephalus australis australis ), South American sea lions ( Otaria byronia ) and marine otters ( Lontra felina ), and an important feeding, nursing, and transit location for humpback whales ( Megaptera novaeangliae ), Orcas ( Orcinus orca ), and blue whales ( Balaenoptera musculus ). We also recorded occasional sightings of fin whales ( B. physalus ), southern right whales ( Eubalaena australis ) and Peale’s dolphins ( Lagenorhynchus australis ). The island coastline also serves as refuge for molting Southern elephant seals ( Mirounga leonina ) and vagrant Subantarctic fur seals ( Arctocephalus tropicalis ). The information presented here highlights Guafo Island as an important breeding, shelter, and feeding site for marine mammals in Chile. The growing anthropogenic pressure on this ecosystem emphasizes the importance of formal protection of this island as a priority site for marine conservation in the Northern Patagonia of Chile.
8 citations
TL;DR: In this article, the authors determined the richness, cobertura, and composition of the macroalgae assemblage in the intertidal zone of Maitencillo, Valparaiso, Chile over the course of three years (2013-2015).
Abstract: espanolResumen: El registro de la diversidad de algas permite reconocer especies que podrian generar informacion base para medidas de manejo, proteccion de los ambientes y presentar nuevas oportunidades de uso. En este contexto, el objetivo del presente trabajo fue determinar la riqueza, cobertura y composicion del ensamble de especies de macroalgas en la zona intermareal de Maitencillo, Valparaiso, Chile, durante 3 anos de monitoreo (2013-2015). Un total de 29 especies fueron registradas, donde 23 de ellas pertenecen a Rhodophyta, 3 a Ochrophyta; clase Phaeophyceae, y 3 a Chlorophyta. La riqueza de especies presento una alta variacion espacio-temporal en el area de estudio, donde las zonas del intermareal y las estaciones del ano presentaron un efecto significativo, explicando un 61 y 31% de su variabilidad, respectivamente. La mayor riqueza especifica se registro en las zonas media y baja (14 especies) durante primavera, y en la zona baja del intermareal (14) durante verano. Los menores valores fueron encontrados en la zona media (2) durante otono. Las zonas del intermareal demostraron ser la variable de mayor importancia a nivel de la comparacion del ensamble de algas, explicando el 53% de la variacion, mientras que la estacionalidad explico el 18% de esta. La mayor cobertura fue registrada en la zona media durante primavera, con predominio de Mazzaella laminarioides y Ulva spp. En la estacion de otono se obtuvo la menor cobertura debido a los procesos de acrecion de arena. En paredones dominaron especies del complejo Pyropia. Los resultados indicaron un claro patron de distribucion vertical y variacion estacional en el ensamble de macroalgas, destacando una mayor presencia de especies de Rhodophyta. La descripcion de la flora bentonica obtenida en este trabajo actualiza la diversidad de algas representativa de la Region de Valparaiso, Chile. EnglishAbstract: Records on the diversity of algae serve as a foundation for establishing management and environmental protection programs, as well as for determining new commercial uses of algae. With this context in mind, the goal of the present study was to determine the richness, coverage, and composition of the macroalgae assemblage in the intertidal zone of Maitencillo, Valparaiso, Chile over the course of 3 years (2013-2015). A total of 29 species were recorded from three phyla - 23 Rhodophyta; 3 Ochrophyta, of the Phaeophyceae class; and 3 Chlorophyta. Species richness presented high spatial and temporal variations, with these variations most significantly explained by intertidal zone (61%) and the seasons (31%). The highest levels of specific richness were recorded in the mid and lower intertidal zones (14 species) in spring, as well as in the lower intertidal zone (14 species) during summer. The lowest values of specific richness were recorded for the mid intertidal zone (2 species) during fall. The distinct levels of the intertidal zone also notably impacted algae assemblage, explaining 53% of variation while the seasons explained 18% of variation. The greatest coverage was recorded in the mid intertidal zone during spring, with a predominance of Mazzaella laminarioides and Ulva spp. complex. In turn, the lowest coverage was found in fall, linked with processes of sand accretion. In rocky walls, the Pyropia complex dominated. Results indicate a marked pattern of vertical and seasonal distribution in the macroalgae assemblage, as well as notably high presence of Rhodophyta species. This benthic flora description serves to update information on the diversity of representative algal species from Valparaiso Region of Chile.
7 citations
TL;DR: Esta especie fue detectada habitando en el humedal El Culebron, Coquimbo, Chile, y surgen las preguntas de cual sera el impacto de esta ispecie introducida en las especies nativas, especialmente si su presa es el camaron de rio Cryphiops caementarius.
Abstract: Australoheros facetus se distribuye en los arroyos costeros de Uruguay y Rio Grande do Sul en Brasil, Cuenca del rio Parana y region inferior del rio Parana en Argentina, con una gran capacidad de adaptacion al ambiente. Esta especie es de interes para la acuariofilia y producto de esta actividad se han producido liberaciones en Sudamerica y Europa. En Chile, su introduccion data desde 1940. Esta especie fue detectada habitando en el humedal El Culebron, Coquimbo, Chile y surgen las preguntas de cual sera el impacto de esta especie introducida en las especies nativas, especialmente si su presa es el camaron de rio Cryphiops caementarius . Para obtener informacion de sus habitos alimentarios, junto con un grupo de estudiantes del colegio Guillermo Cereceda Rojas de Coquimbo, se efectuaron 3 muestreos entre el 2015 y 2016. Se capturaron 24 individuos con un 37,5% de hembras, los ejemplares mas pequenos y los de mayor peso fueron machos. A los peces capturados se les registro su longitud total (L t ), peso total (P t ) y sexo. Se determino la proporcion de sexo, distribucion de talla, relacion L t /P t . Se analizo su contenido estomacal, aplicando los indices de frecuencia de ocurrencia, numerica y gravimetrica, determinando el indice de importancia relativa (IIR) y su respectivo porcentaje. Se obtuvo como resultado un crecimiento isometrico y no hubo diferencias en la relacion L t /P t para hembras y machos. Se registro la presencia de 20 item presa (restos de plantas, Annelidae, Mollusca, Arthropoda y Pisces). Las presas mas importantes fueron peces (37,5% IIR), Cryphiops caementarius (25% IIR) y Chironomidaes (13,8% IIR). Se recomienda evaluar la presencia de esta especie, en otros sistemas hidrograficos de la region y en especial, el impacto de A. facetus en la depredacion de camaron de rio.
6 citations
Abstract: espanolResumen: El Alto Golfo de California y Delta del Rio Colorado es un area que se encuentra inmersa en un conflicto ecologico, economico, politico y social debido a la pesca ilegal de totoaba Totoaba macdonaldi y la posible extincion de vaquita marina Phocoena sinus Esto ultimo ha provocado el cierre de todas las pesquerias en la region salvo la de curvina golfina Cynoscion othonopterus la cual es la unica especie con permiso de explotacion Por lo tanto, el objetivo principal fue evaluar el estado de salud de la pesqueria mediante los indicadores de sustentabilidad de Froese en el Alto Golfo de California durante las temporadas de pesca 2008, 2013, 2014 y 2015 Los resultados mostraron que la produccion anual de curvina golfina presenta fluctuaciones, resaltando el periodo 2012-2016, donde las capturas totales con excepcion de 2014, sobrepasaron la cuota de captura establecida por el Instituto Nacional de la Pesca La longitud de madurez para los anos estudiados fueron: 2008= L50: 502 mm (IC= 490-514 mm), 2013= L50: 559 mm (IC= 544-576 mm), 2014= L50: 499 mm (IC= 476-518 mm), y 2015= L50: 480 mm (IC= 445-510 mm) Con base en los indicadores de sustentabilidad, se demuestra que la pesqueria de curvina golfina esta dirigida hacia los organismos de mayor longitud (mega-reproductores) Se concluye que actualmente la curvina golfina manifiesta problemas de sobreexplotacion y por ende su aprovechamiento no es sustentable Esto sugiere la necesidad realizar ajustes y actualizaciones a las actuales medidas de manejo EnglishAbstract: The Upper Gulf of California and Colorado River Delta is a zone which is immersed in an ecological, economic, political and social conflict That is because of the Totoaba Totoaba macdonaldi illegal fishing and the Vaquita Phocoena sinus potential extinction This issue has driven to ban all the region's fisheries with the exception of the Gulf corvina Cynoscion othonopterus which is the only of the finfish species with operating license Therefore, the main objetive was to evaluate the fishery's health condition through the Froese sustainability indicators in Upper Gulf of California during 2008, 2013, 2014 and 2015 fishing seasons The results showed that the Gulf corvina annual production ratio showed fluctuations, highlighting in the 2012-2016 period, when the whole fishing captures with the exception of 2014, surpassed the established quota by the National Institute of Fishery (Instituto Nacional de Pesca) The size-at-maturity were: 2008= L50: 502 mm (IC= 490-514 mm), 2013= L50: 559 mm (IC= 544-576 mm), 2014= L50: 499 mm (IC= 476-518 mm), and 2015= L50: 480 mm (IC= 445-510 mm) Based on the sustainability indicators, it is demonstrated that the Gulf corvina fishery is directed towards the organisms of greater length (mega-spawners) Finally it is concluded that Gulf corvina currently shows problems of over-exploitation and therefore its exploitation is not sustainable This suggests the need to make adjustments and updates to current management measures
6 citations
6 citations
TL;DR: In this article, the authors found 395 dead seabirds, of which 382 were identified and grouped into 21 species, including Peruvian booby, Guanay cormorant, and Kelp gull.
Abstract: Monitoring of seabirds stranded on beaches can provide information about their causes of death, such as bycatch in fishing activities or oil spills. During a year we monthly monitored the Coquimbo Bay, north Chile, to quantify the number of seabirds and species stranded. We found 395 dead seabirds, of which 382 were identified and grouped into 21 species. The most abundant were the Peruvian booby with 115 individuals (30%), the Guanay cormorant with 83 individuals (22%) and the Kelp gull with 65 individuals (17%). The most abundant and frequent species were those nesting in the Coastal System of Coquimbo. Mortality mainly affected seabirds that feed on anchoveta, which is the main target resource of purse seine fishing. We suggest that the incidental mortality caused by fishing is chronic and relatively constant during the year. A long-term monitoring program is needed to better estimate the mortality and the factors that influence the interaction of seabirds with fishing gears.
6 citations
TL;DR: A review of studies that have addressed to date the effect of both climate oscillations and global warming on populations of tropical tunas was performed in this article, where the main challenges of fisheries biology in relation to the management of stocks of tropical tuna, an important fishery resource, in the context of climate change.
Abstract: espanolResumen: El termino ‘tunido tropical’ se refiere a un grupo de especies de peces escombriformes que incluye al listado o barrilete (Katsuwonus pelamis), el patudo (Thunnus obesus) y el rabil (Thunnus albacares), que presentan una amplia distribucion pantropical, y cuyo optimo de temperatura superficial del agua del mar en el que habitan se situa en torno a los 20oC Actualmente, dos de estas especies se encuentran entre las 7 especies con mayores volumenes de desembarque a nivel mundial Se preve que en el futuro los stocks de tunidos tropicales jueguen un papel fundamental para salvaguardar la seguridad alimentaria El objetivo de este trabajo fue presentar los principales retos de la biologia pesquera en relacion a la gestion de las poblaciones de tunidos tropicales en un contexto de cambio climatico Para esto se revisaron los estudios que se han abordado hasta el presente sobre el efecto tanto de las oscilaciones climaticas, como del calentamiento global en las poblaciones de tunidos tropicales EnglishAbstract: The term ‘tropical tuna’ refers to skipjack (Katsuwonus pelamis), bigeye (Thunnus obesus) and yellowfin tunas (Thunnus albacares), which have a wide pantropical distribution Tropical tunas inhabit waters with a sea surface temperature with an optimal value around 20°C Currently, two of these species are among the 7 species with higher landings worldwide In addition, it is expected that future tropical tuna stocks play a key role safeguarding food security The aim of this paper was to review the studies about the effect of both climatic oscillations and global warming on tropical tuna populations Moreover, it warns about the main challenges of fisheries biology in relation to the management of stocks of tropical tunas, an important fishery resource, in the context of climate change For this, a review of studies that have addressed to date the effect of both climate oscillations and global warming on populations of tropical tunas was performed
6 citations
TL;DR: The results highlight the need of further researches for monitoring the colonies of this species considering future scenarios of rising temperature and no relationship was found between depth and percentage of affected colonies.
Abstract: Records of mortality after a high temperature event in 2014 in the white gorgonian Eunicella singularis were compiled in six different locations around the Chafarinas Islands. Quadrats were used to quantify dead colonies, colonies affected by epibionts and healthy colonies at different depths. No relationship was found between depth and percentage of affected colonies; however, differences in the mortality among sites were detected. On average, 43% of the colonies of E. singularis were found dead, 1% damaged and 36% healthy. These results highlight the need of further researches for monitoring the colonies of this species considering future scenarios of rising temperature.
TL;DR: This study describes and classifies a case of multiple malformations in an unborn blue shark Prionace glauca fetus, which was extracted from a gravid female captured during a research campaign addressed to the biological study of sharks in northern and central Chile.
Abstract: This study describes and classifies a case of multiple malformations in an unborn blue shark Prionace glauca fetus, which was extracted from a gravid female captured during a research campaign addressed to the biological study of sharks in northern and central Chile. The analyzed specimen shows tetrophthalmia with unilateral synophthalmia, anomaly characterized by the existence of 4 ocular globes, two of which are partially fused. In addition, the axial skeleton of the fetus shows thoracic lordosis and helical torsion in the abdominal-caudal portion. This is the first world report of tetrophthalmia with unilateral synophthalmia in chondrichthyans.
TL;DR: In this paper, the authors investigated the environmental impact of offshore floating sea cages and the influence of runoff on cage fish farming in SE Gulf of California via the analysis of the physico-chemical profiles of the water column and sediments.
Abstract: This study investigated the environmental impact of offshore floating sea cages and the influence of runoff on cage fish farming in SE Gulf of California via the analysis of the physico-chemical profiles of the water column and sediments, located in SE Gulf of California, Mexico. Water and sediment samples were analyzed for physico-chemical parameters. In general, nitrates showed the highest concentrations of nutrients in the potential impact station (1.92 mg L-1). The results displayed temporal variations in the NH4 +, NO3-, and PO43- in the water column as well as variations in the clay and organic matter in the sediment. The observed trends of these parameters were toward higher concentration in the potential impact and control stations .
TL;DR: Results suggest that larvae differently utilize these two areas as a refuge or for feeding, and that adults might be coupling their spawning periods with short-term oceanographic features.
Abstract: This paper presents an analysis of spatial and temporal patterns in the fish larvae composition of two geographically adjacent nearshore areas within the Humboldt Current System (HCS), northern Chile. Five surveys were performed at Isla Santa Maria (ISM) and Punta Coloso (COL), Mejillones Peninsula. Ichthyoplankton were collected every 15 days in 2014 during the austral autumn-winter (May to August). A total of 412,410 fish larvae belonging to 36 taxa were identified, a high abundance compared with other HCS regions. Data also revealed similarities in species recorded compared with central Chile as well as differences compared with central Peru; a number of families were shared between these HCS regions and other systems (e.g., Canarias Current System). ISM was dominated by intertidal-subtidal species (e.g., Helcogrammoides cunninghami), while Engraulis ringens was most abundant at COL. Several species were positively correlated with dissolved oxygen (e.g., Auchenionchus microcirrhis), as well as temperature and Ekman transport (e.g., Sebastes oculatus), while the presence of others is negatively related to the same environmental parameters (e.g., Graus nigra). Results suggest that larvae differently utilize these two areas as a refuge or for feeding, and that adults might be coupling their spawning periods with short-term oceanographic features. Larval fish assemblages of nearshore areas in northern Chile are described here for the first time and highlight the important role of these two areas in the early developmental stages of fish species.
TL;DR: Observaciones durante 6 temporadas de desove en la zona intermareal rocoso de Montemar, bahía de Valparaíso, Chile, constituye un aporte sobre aspectos no descritos del comportamiento reproductivo y the ontogenia of A. porosus.
Abstract: Con el objetivo de estudiar el comportamiento reproductivo y describir los huevos y larvas del bagre Aphos porosus (Pisces: Batrachoididae), se realizaron observaciones durante 6 temporadas de desove en la zona intermareal rocoso de Montemar, bahia de Valparaiso, Chile. Se mantuvieron peces adultos en el laboratorio y se controlo el desarrollo de huevos y larvas. Tambien se realizo la fertilizacion artificial de huevos en el laboratorio. Se observo la llegada de los machos a la costa a partir de octubre, seguidos de las hembras en noviembre y diciembre de cada ano. Los huevos fueron adheridos a las paredes verticales o inferiores de las piedras y grietas de las pozas del intermareal de Montemar y en las paredes de los estanques. Su diametro fue de 5,3 ± 0,3 mm. La eclosion se produjo a los 18 d a 18,6°C y a los 21 d a 16,3°C. Las larvas recien eclosionadas midieron en promedio 4,8 mm de longitud total (LT) (rango entre 4,3 a 5,1 mm LT) y realizaron parte de su desarrollo adheridas al sustrato por el saco vitelino. Antes de consumir completamente el vitelo, las larvas ya presentaban el patron de pigmentacion y la forma del cuerpo similar a la de los juveniles. Al terminar de absorber el vitelo, las larvas midieron 20,5 a 24,0 mm LT y se liberaron del sustrato entre los 60 y 65 d de edad. Este trabajo constituye un aporte sobre aspectos no descritos del comportamiento reproductivo y la ontogenia de A. porosus, dentro del conjunto de especies de peces de la costa de Chile
TL;DR: It is concluded that the juveniles of Notothenia sp.
Abstract: Notothen fishes (Nototheniidae) have been recorded on the coasts of South America, from 35°S to southern. Little is known about the biology of intertidal notothen fishes or their relationships with other species, including parasites. Here, we analyzed the parasitic fauna of a species of Notothenia collected from the rocky intertidal of Lebu, south-central Chile (36°S) and compared the parasite community of this host with other 9 fish species commonly found in intertidal rocky pools. Among the tested species, Notothenia sp. had the highest parasite richness (21 parasitic taxa vs. 1 to 9 parasitic taxa). The composition of parasite species was different among fishes, with similarity indices between 0 and 33%. The parasite composition of Notothenia sp. was most similar to Calliclinus geniguttatus (27%). The most abundant and prevalent parasites found in Notothenia sp. were the copepod Caligus cf . cheilodactyli , Tetraphyllidea larvae, anisakid nematodes, and several acanthocephalan species, which are typical of other fish from the subtidal and bento-demersal zones. Therefore, we conclude that the juveniles of Notothenia sp. were a few months old and had their parasites when reaching the intertidal zone, acquired some generalist parasites during their stay in this habitat, such as Holobomolochus chilensis and Lecithaster macrocotyle . Most notothen fishes are from Antarctic and Sub-Antarctic waters, therefore, it is possible that this fish came from another habitat but also from the austral region of South America. Notothenia sp. could not be specifically identified because of different results between morphological and genetic analyses.
TL;DR: In this paper, a trabajo estudio of the habitos alimentarios combinando analisis estomacales and estabilidad isotopica was conducted.
Abstract: El besugo, Epigonus crassicaudus, es una especie de importancia economica para la actividad pesquera que opera en el centro-sur de Chile. A pesar de ello, poco es lo que se conoce respecto a su biologia. En este sentido, este trabajo estudio los habitos alimentarios combinando analisis estomacales y de estabilidad isotopica. Los resultados del analisis dan cuenta de la importancia de los peces mesopelagicos (Myctophidae, Stomiidae) en la dieta con un aporte del 80%, seguido por crustaceos ( Sergestes arcticus ) alcanzando un 10%. No se detectaron diferencias en la dieta en peces con distinto grado de madurez sexual. En tanto, los valores de los isotopos de nitrogeno y carbono mostraron valores de promedio de 17,12 ± 1,1 δ 15N y de -17,51 ± 0,7 δ 13C, respectivamente. La constitucion de valores de δ 13C fue proporcional al tamano corporal de los besugos: individuos de mayor tamano habitan en ambientes mas demersales que ejemplares de menor tamano. De acuerdo a estos resultados, el besugo se situa como consumidor secundario.
TL;DR: Biofouling affects global aquaculture with significant impacts on productivity and profitability, especially in marine shellfish culture, where both the target culture species and/or infrastructure are exposed to a diverse array of fouling organisms.
Abstract: Biofouling affects global aquaculture with significant impacts on productivity and profitability, especially in marine shellfish culture, where both the target culture species and/or infrastructure are exposed to a diverse array of fouling organisms In oyster culture, fouling of stock causes physical damage, mechanical interference, biological competition and environmental modification, with infrastructure also colonized The present study describes the composition of the biofouling community inhabiting the surface of the mangrove oyster Crassostrea rhizophorae , cultivated in an Amazon estuary, in the state of Para, northern Brazil In total, 6,124 macroinvertebrates were collected during July, August, October and December 2013 Collected epifauna was represented by 5 groups (Bivalvia, Gastropoda, Polychaeta, Crustacea and Anthozoa), 20 families and 37 species Bivalvia was the most abundant class, with the mussel Mytella charruana by far the most dominant species with 5,183 individuals Knowledge about the composition of biofouling as well as identifying the main species that cause direct impacts allows more tailored and strategic management options, minimizing the often-significant costs associated with biofouling control (antifouling)
TL;DR: Using mitochondrial DNA and phylogenetic approaches, 6 individuals of the species Xenobrama microlepis are identified in a haul targeting the southern Ray’s bream taken by artisanal fishermen close to Chilean coast.
Abstract: Species that occur in low abundances and that are morphologically similar to the target fish are often undetectable in fisheries hauls; however, they add to the catch statistics of the target species. Using mitochondrial DNA and phylogenetic approaches we identified 6 individuals of the species Xenobrama microlepis in a haul targeting the southern Ray’s bream ( Brama australis ) taken by artisanal fishermen close to Chilean coast. The presence of X. microlepis increases the regional marine biodiversity of fishes in Chilean waters, and fisheries managers should pay attention to the hidden biodiversity in the fishery statistics.
TL;DR: The use of molecular identification by COI is recommended to identify Auxis larvae to the species level, as well as in other marine fish larvae collected in other regions of the world, that have identification troubles.
Abstract: The larvae of the Auxis genus are abundant in the Gulf of California during summer; however, their identification to the species level by morphological methods is a challenge. The goal of this study was to identify A. thazard and A. rochei larvae for first time, through molecular markers using COI sequences of mtDNA, and look for distinctive morphological characteristics between species, mainly in pigmentation patterns. Larvae were obtained by zooplankton tows in 3 oceanographic cruises in the southern Gulf of California and adjacent waters. The presence of A. thazard and A. rochei larvae was genetically confirmed. The sequences of 7 larvae showed genetic divergences lower than 1% when were compared to sequences of A. thazard adults, while 15 larvae showed genetic divergences lower than 2% when where compared to sequences of A. rochei adults. Genetic divergences between both Auxis species were higher than 2%. These results suggest the spawning of both species in the Gulf of California. On the other hand, pigmentation patterns and morphometric characteristics, in all larval stages, did not permit the secure differentiation between species. Thus, the use of molecular identification by COI is recommended to identify Auxis larvae to the species
TL;DR: Copepod parasites collected from different sites along corporal body of sharks and rays captured onboard cruise OCEARCH concluded they are generalist parasites of wide geographic distribution.
Abstract: In the Chilean coast, sharks and rays are one of the least studied fish groups, therefore quantitative data about theirparasites are scarce or almost non existing. Copepod parasites were collected from different sites along corporal body of Prionace glauca (n= 12) and of Isurus oxyrinchus (n= 1) captured onboard cruise OCEARCH during March and April 2014. Three species belonging to the Pandaridae family were identified: Echthrogaleus coleoptratus , Dinemoura producta and Nessipus orientalis . The latter species is here recorded for the first time in Chilean waters. These copepods did not show infection site preferences along host body. Considering the wide range of hosts described for these parasite species, it is concluded they are generalist parasites of wide geographic distribution.
TL;DR: Estas diatomeas marinas fueron ricas en aceites esenciales, alcaloides, y terpenos, y el perfil fitoquímico cualitativo indicó that estas di atomeasmarinas fuen ricas in aceites económica, al caleides, and terpeno.
Abstract: Marine diatoms synthesize and secrete a variety of secondary metabolites with potential applications in the pharmaceutical industry, however their study is still limited. Therefore, the objective of this work was to isolate and culture the species Chaetoceros curvisetus, Asterionella japonica , and Biddulphia mobiliensis from Santa Lucia Bay in Acapulco, Guerrero, Mexico, as well as to determine the antibacterial activity against bacteria of clinical importance and the analysis of qualitative phytochemical profile of their extracts obtained. Biomass yield was 219.62 ± 0.99; 151.12 ± 1.41, and 109.04 ± 1.48 mg for C. curvisetus, A. japonica , and B. mobiliensis , respectively. Hexane, dichloromethane and acetone extracts were obtained for each species and the qualitative phytochemical profile indicated that these marine diatoms were rich in essential oils, alkaloids, and terpenes. C. curvisetus extract was observed to possess the highest antibacterial activity with Minimum Inhibitory Concentrations (MIC) between 0.5 and 2 mg mL-1 for ATCC bacteria, and 8 and 16 mg mL-1 for E. coli BLEE-producing strains.
TL;DR: The dominant zooplankton of the La Mancha lagoon, Veracruz, Mexico was analyzed with the objective of evaluating its seasonal and diel variability, as well as the influence of the main environmental variables on this variability.
Abstract: espanolResumen: El zooplancton dominante de la laguna La Mancha, Veracruz, Mexico, fue analizado con el objetivo de evaluar su variabilidad estacional y nictimera, asi como la influencia que sobre el ejercen las principales variables ambientales. De mayo 2012 a abril 2013, cada mes se realizo un ciclo de 24 h, tomando muestras cada 4 h, en la boca de la laguna. Simultaneamente a la toma de muestras de zooplancton, se registraron parametros ambientales in situ como la temperatura, oxigeno disuelto, salinidad, clorofila a y numero de celulas fitoplanctonicas. Se capturaron 54 taxa (principalmente del holoplancton) y 10 de ellos fueron considerados dominantes (abundancia total > 0,5%). La comunidad estuvo dominada por dos especies de copepodos (Acartia tonsa y Pseudodiaptomus pelagicus), asi como por larvas zoea de braquiuros (~85%). La abundancia total del zooplancton mostro pulsos significativos a lo largo del ano, uno en febrero-marzo dominado por copepodos y otro en septiembre-octubre, dominado por larvas de decapodos. A pesar de que la abundancia total del zooplancton fue mayor en la noche, solo P. pelagicus, anfipodos, megalopas y otras larvas de decapodo fueron significativas durante este periodo. De acuerdo con un Analisis de Correspondencia Canonica, el estado de la boca (abierta/cerrada), numero de cianofitas y precipitacion fueron los factores ambientales mas importantes en la determinacion de la abundancia del zooplancton dominante. EnglishAbstract: The dominant zooplankton of the La Mancha lagoon, Veracruz, Mexico, was analyzed with the objective of evaluating its seasonal and diel variability, as well as the influence of the main environmental variables on this variability. From May 2012 to April 2013, every month a 24-h cycle was completed, taking samples every 4 h, at the mouth of the lagoon. Simultaneously with zooplankton sampling, in situ environmental parameters such as temperature, dissolved oxygen, salinity, chlorophyll a and number of phytoplankton cells were recorded. We collected 54 taxa (mainly holoplankton) and 10 of them were considered dominant (total abundance > 0.5%). The zooplankton community was dominated mainly by two species of copepods (Acartia tonsa and Pseudodiaptomus pelagicus), as well as zoea larvae of brachyura (~85%). At seasonal level, the total abundance of zooplankton showed significant pulses throughout the year, one in February-March dominated by copepods and another in September-October, dominated by decapod larvae. On a diel scale, although total zooplankton abundance was significantly higher at night, only P. pelagicus, amphipods, megalopae, and other decapod larvae showed significant differences at this level. According to a Canonical Correspondence Analysis, the mouth stage (open/close), the number of cyanophytes and precipitation were the most important environmental factors in determining the abundance of the dominant zooplankton.
TL;DR: The rbc L analysis showed that the longbladed specimens inhabiting Valparaiso Bay correspond to Porphyra mumfordii, which constitutes the first record of P. momfordii for central Chile.
Abstract: The genus Porphyra , commonly found along Chilean coast, is an important commercial algal food known as nori. There are some specimens of Porphyra found at Montemar Marine Protected Area (32°57’S; 71°33’W) in Valparaiso Bay, which taxonomical identity is not clear. This study aimed to identify long-bladed specimens of Porphyra inhabiting the upper, mid and lower intertidal in Valparaiso Bay. To do so, 30 thalli of Porphyra were collected during the winter of 2015 in Montemar. All samples were subjected to rbc L molecular marker amplification. However, only 18 individuals were sequenced successfully. In addition, a morphological description was conducted. The rbc L analysis showed that the longbladed specimens inhabiting Valparaiso Bay correspond to Porphyra mumfordii . Differences in size and color of thalli found on each intertidal level were recorded. This research constitutes the first record of P. mumfordii for central Chile.
TL;DR: The presence of this species in the southeast of the Gulf of Mexico is reported, increasing up to five, the number of the species of the subfamily Dasyatinae in this zone.
Abstract: A Bathytoshia centroura female of 181 cm disk width was found during the monitoring of small scale fishery in the state of Tabasco, Mexico. The specimen was caught by a gill net vessel at 32 km northeastern of the port of Sanchez Magallanes, at 78 m depth. Large size and spacing of mid-dorsal bucklers, conspicuous tubercles on the outer parts of disc and tail with numerous rows of small spines were used to verify the identification. The presence of this species in the southeast of the Gulf of Mexico is reported, increasing up to five, the number of the species of the subfamily Dasyatinae in this zone.
TL;DR: In this paper, the authors describe and document experiences applying standardized and verified methodological steps for deploying satellite transmitters on hard shell marine turtles and present a documented and step-by-step viable description on the path to have clear and versatile basis as reference for the satellite transmitter deployments.
Abstract: Sea turtles are migratory species that occupy several marine and coastal habitats along their different life stages. The study of the spatial and temporal distribution of these vertebrates has been revolutionized with technological advances such as satellite telemetry, which in the last two decades has substantially increased its implementation. This technology attends the need of knowing and locating their critical habitats (such as inter-nesting, migrating, feeding and mating) as well as know their migratory movements for the understanding of their biology and protection through the deployment of satellite transmitters on sea turtle individuals. Because the cost of a satellite transmitter is high, its effective deployment on a sea turtle in a quickly, safely, and firmly way is of vital interest to the researcher to ensure that the transmitter persists for an extended time maximizing the information contribution and benefit the research. In this context, the objective of this contribution is to describe and document experiences applying standardized and verified methodological steps for deploying satellite transmitters on hard shell marine turtles. This contribution represents a documented and step-by-step viable description on the path to have clear and versatile basis as reference for the satellite transmitter deployments.
TL;DR: The larvae of the starry butterfish Stromateus stellatus share the general shape of the family, with a body that increases notably in depth and preanal length during development; they present characteristic pigmentation that differentiates them from larvae of related species.
Abstract: Although larvae of the starry butterfish Stromateus stellatus (Family Stromateidae) are often observed in coastal waters of the southeastern Pacific Ocean, there is no formal description of the species’ early development. Using ichthyoplankton samples collected off central Chile, the larval development, including observations on osteology of late postflexion stage larvae, and temporal differences in larval densities in nearshore waters are described. Preflexion larvae have a short, rounded snout and a distinctive pigment pattern. Notable transformations throughout the development from early preflexion to postflexion are the increase in preanal length from less than 40 to more than 50% of body length (BL) and in body depth from 5 to 33% BL. Initially, larvae develop 3 melanophores on the dorsal contour of the body, small melanophores at the jaw angle, and a row along the ventral margin of the tail. Large melanophores dorsal and ventral to the gut, intestine, and above the swim bladder are also present in early preflexion. After notochord flexion, larvae develop light pigmentation on the sides of the tail, and heavy pigmentation on the head and trunk. The larvae share the general shape of the family, with a body that increases notably in depth and preanal length during development; they present characteristic pigmentation that differentiates them from larvae of related species. The larvae were recorded in low density (less than 6 ind. 100 m -3 ) in the nearshore during mid-spring (October) and early summer (late December until mid-January) off central Chile. The occurrence of the larvae in the plankton recorded in central Chile is consistent with information from literature of larval distribution and reproductive activity in adults.
TL;DR: The anatomy, disposition and extension of the main cephalic sensory canals and associated structures in a clupeiform from Chile, S. bentincki, are provided for first time to obtain a better understanding of the systematic and comparative ethology of the sardines.
Abstract: The anatomy, disposition and extension of the main cephalic sensory canals and associated structures in a clupeiform from Chile, S. bentincki , are provided for first time. Ten cephalic canals were identified: supraorbital, infraorbital, anterorbital, postorbital, preopercular, mandibular, ethmoidal, temporal, postemporal and extrascapular. Due to the scarce literature in sensory structures regarding Chilean Clupeiformes, it is necessary more studies about those features for the respective comparisons to obtain a better understanding of the systematic and comparative ethology of the sardines and to have an integral view of the cephalic sensory system of canals in this order.
TL;DR: The stock of tintoreras no esta sobreexplotado as mentioned in this paper, but it is for shortfin mako in the North-eastern Atlantic Ocean and the stock of blue sharks is not overexploited.
Abstract: espanolResumen: Las tintoreras (Prionace glauca) y los marrajos (Isurus oxyrinchus) son especies objetivo explotadas por los palangreros espanoles y portugueses. Las tripulaciones desembarcan los tiburones en la lonja de Vigo (Espana). La flota palangrera perdio 15 unidades de pesca entre 2004 y 2016. Del 2001 al 2016, las cantidades desembarcadas de marrajos disminuyeron cuando las cantidades de tintoreras subieron notablemente. Segun los informes del ICCAT, el stock de tintorera no esta sobreexplotado. Sin embargo, el stock del marrajo si lo estaria en el Atlantico noreste. Los tiburones capturados y vendidos en la lonja son en la gran mayoria, juveniles, siendo la madurez sexual muy tardia para ambas especies. Las autoridades deben tomar medidas para reducir la presion de la pesca ejercida sobre ambas especies. EnglishAbstract: Blue shark (Prionace glauca) and shortfin mako (Isurus oxyrinchus) are species exploited by the Spanish and Portuguese longline fleet. They land sharks in the fish market at Vigo (Spain). The number of longliners decreased between 2004 and 2016 (less 15 boats). Landings of shortfin mako have decreased and those of blue shark increased between 2001 and 2016. In accordance with ICCAT informs, the blue shark stock is not overexploited. But it is for shortfin mako in the North-eastern Atlantic Ocean. The sharks landed in a fish market are mainly juvenile, the maturity age being late for both species. The authorities must establish measures to reduce fishing pressure.
TL;DR: Biological traits of the sicklefin smooth-hound shark, M .
Abstract: Mustelus lunulatus is the most important shark demersal species in the landings of the Ecuadorian artisanal fishery, this study was carried out to expand the knowledge about size, sex, type of growth (isometric or allometric) and reproductive aspects in males of the species. Biological traits of the sicklefin smooth-hound shark, M . lunulatus, caught in the Pacific coast of Ecuador were assessed by examining 199 individuals ranging from 41.2 to 135.0 cm in total length (TL). The means TL did not show significant differences between sexes. The sex ratio was not different from 1:1 and the weightlength relationship did not showed significant differences between males and females. Both sexes have a growth of isometric type ( b males= 3.05 and b females= 3.15). Total length at sexual maturity (TL50) of male M . lunulatus , calculated from the clasper condition, was estimated to be 97.2 cm. The present study provides new information regarding the biology of M. lunulatus in Ecuadorian waters.