Spatio-temporal variation in the growth of coral fragments of opportunity in the Eastern Tropical Pacific: implications for coral reef restoration

Introduction: Coral-reef communities are considered one of the most biodiverse, but also most threatened, marine ecosystems, and the accelerating loss of habitat over the past decades warrants active intervention. Objective: The present study demonstrates the successful implementation of a low-impact restoration technique in three Central Mexican Pacific degraded coral communities, using a protocol based on natural fragmentation (''fragments of opportunity") of the branching coral Pocillopora spp., considered the most abundant and primary carbonate-producing coral species of the Eastern Tropical Pacific. Methods: The restoration program was implemented in two offshore and one inshore coraline areas. The relationships between seawater temperature and coral survival, growth, and attachment rate were assessed over one year, with 183 fragments monitored each month. Results: The mean coral growth rate was 3.3 ± 0.1 mm mo-1, with annual growth rates in length and width of 39.9 ± 14.2 and 36.5 ± 19.5 mm yr-1, respectively. Self-attachment efficiency was 78 % and the survival rate was high (84 %). The growth rate differed significantly among reefs. Conclusions: Upon monitoring directly fragmented corals over a year, growth rates were deemed high enough to merit active restoration in the region. However, our data show that structural and abiotic differences and seasonal variability must be considered overall in successful long-term coral community restoration initiatives in the eastern Pacific region.

Introducción: Las comunidades de arrecifes de coral se consideran uno de los ecosistemas marinos con mayor biodiversidad, pero también los más amenazados, y la pérdida acelerada de hábitat en las últimas décadas justifica la implementación de una intervención activa. Objetivo: El presente estudio demuestra la implementación exitosa de una técnica de restauración de bajo impacto basada en la fragmentación natural (''fragmentos de oportunidad") del coral ramificado Pocillopora spp., la cual es la especie coralina más abundante y principal productora de carbonato del Pacífico Oriental Tropical. Métodos: El programa de restauración se implementó en dos sitios lejos de la costa y un sitio cercano a la costa, con comunidades coralinas degradadas. Las relaciones entre la temperatura del agua de mar y la supervivencia, el crecimiento y la tasa de adhesión de los corales se evaluaron durante un año con 183 fragmentos monitoreados cada mes. Resultados: La tasa media de crecimiento coralino fue de 3.3 ± 0.1 mm mo-1, con tasas de crecimiento anual en largo y ancho de 39.9 ± 14.2 y 36.5 ± 19.5 mm año-1, respectivamente. La eficiencia de la auto-adherencia fue del 78 % y la tasa de supervivencia fue alta (84 %). La tasa de crecimiento difirió significativamente entre los arrecifes. Conclusiones: Al monitorear directamente los corales fragmentados durante un año, las tasas de crecimiento se consideraron lo suficientemente altas como para merecer una restauración activa en la región. Sin embargo, nuestros datos muestran que las diferencias estructurales y abióticas y la variabilidad estacional deben considerarse en general en las iniciativas exitosas de restauración de comunidades de coral a largo plazo en la región del Pacífico oriental.

Stable isotope analysis reveals partitioning in prey use by Kajikia audax (Istiophoridae), Thunnus albacares, Katsuwonus pelamis, and Auxis spp. (Scombridae) in the Eastern Tropical Pacific of Ecuador

Kajikia audax, Thunnus albacares, Katsuwonus pelamis, and Auxis spp. occupy high and middle-level trophic positions in the food web. They represent important sources for fisheries in Ecuador. Despite their ecological and economic importance, studies on pelagic species in Ecuador are scarce. This study uses stable isotope analysis to assess the trophic ecology of these species, and to determine the contribution of prey to the predator tissue. Isotope data was used to test the hypothesis that medium-sized pelagic fish species have higher δ15N values than those of the prey they consumed, and that there is no overlap between their δ13C and δ15N values. Results showed higher δ15N values for K. audax, followed by T. albacares, Auxis spp. and K. pelamis, which indicates that the highest position in this food web is occupied by K. audax. The stable isotope Bayesian ellipses demonstrated that on a long time-scale, these species do not compete for food sources. Moreover, δ15N values were different between species and they decreased with a decrease in predator size.(AU)

Kajikia audax, Thunnus albacares, Katsuwonus pelamis e Auxis spp. ocupam posições tróficas intermedias e/ou elevadas nas cadeias alimentares. Estas espécies representam um importante recurso pesqueiro no Ecuador. Apesar da sua importância económica e ecológica, estudos nestas espécies pelágicas no Ecuador são raras. Este estudo usa isótopos estáveis para avaliar o seu nível trófico de modo a determinar a contribuição das suas presas para os tecidos destes predadores. Dados dos isótopos foram usados para testar a hipótese de que estas espécies de peixes pelágicos possuem valores mais elevados de δ15N do que daqueles das presas consumidas, e que não existe uma sobreposição entre os valores de δ13C e δ15N. Resultados mostram que valores mais elevados de δ15N para K. audax, seguidos por T. albacares, Auxis spp. e K. pelamis, indicam que a posição mais elevada na cadeia alimentar é ocupada por K. audax. Elipses Bayesianas de isótopos estáveis demonstram que, a uma escala de longo-termo, estas espécies de peixes não competem pelos recursos. Adicionalmente, os valores de δ15N são diferentes entre espécies de peixe estudadas e estes valores decrescem com a diminuição do tamanho do predador.(AU)

Composition, density and biomass of fish community from the surf zone as a function of the lunar cycle at Miramar Beach in Cabedelo, Paraíba

The influence of the moon cycles on the ichthyofauna has been little studied in the surf zone. In this study, the number of species, density and biomass were evaluated as a function of the moon. A total of 49 species distributed in 24 families were captured in two areas of Miramar beach. The mean density was significant high in the weaning and low in the new moon, while density and biomass together showed differences for areas. The most abundant species were Anchoa tricolor and Trachinotus falcatus (new moon), and Anchovia clupeoides showed significant differences in the waning moon. The RDA indicates that turbidity influenced significantly the presence of two species group. The group I were represented by Stellifer brasiliensis, Trachinotus goodei, A. clupeoides, Chilomycterus spinosus and Conodon nobilis that occurred on the waning and new phases in both areas, while the group II were represented by Polydactylus virginicus and Haemulopsis corvinaeformis in the full moon. The surf zones may also be strongly governed by the lunar phases. Therefore, the results found in this study, showed that the biological interactions between the species with turbidity and moon might explain the density and biomass variations for some species in the surf zone.(AU)

A influência das fases lunares sobre a ictiofauna tem sido pouco estudada na zona de arrebentação. Nesse estudo, foram avaliadas, o número de espécies, densidade e a biomassa da ictiofauna em função da lua. Foram capturadas 49 espécies distribuídas em 24 famílias em duas áreas na Praia de Miramar. A densidade foi significativamente elevada nas luas minguante e nova. Além disso, a densidade e biomassa juntas mostraram diferenças entre as áreas. As espécies mais abundantes na lua nova foram Anchoa tricolor e Trachinotus falcatus, e Anchovia clupeoides teve uma maior abundancia na lua minguante. O RDA, indicou que a turbidez influenciou significativamente a presença de dois grupos distintos. O grupo I, representado por Stellifer brasiliensis, Trachinotus goodei, A. clupeoides, Chilomycterus spinosus e Conodon nobilis estiveram presentes nas luas minguante e nova em ambas as áreas, e o grupo II, representado por Polydactylus virginicus e Haemulopsis corvinaeformis na lua cheia. As zonas de arrebentação também podem ser reguladas fortemente pelas fases lunares. Os resultados mostraram que as interações biológicas entre as espécies com a turbidez e as fases lunares podem explicar as variações de densidade e biomassa para algumas espécies na zona de arrebentação.(AU)

Fish assemblages in three fringed mangrove bays of Santa Cruz Island, Galapagos Marine Reserve / Ensamblaje de peces en tres bahías con bordes de manglar en la Isla Santa Cruz, Reserva Marina de Galápagos

Abstract Mangrove-fringed bays are highly variable ecosystems that provide critical habitats for fish species. In this study we assessed the fish assemblage in three mangrove-fringed bays (Punta Rocafuerte, Saca Calzón and Garrapatero) in the Southeast side of Santa Cruz Island, Galapagos Marine Reserve. Using gillnets, we carried out a total of 108 fieldtrips from January 2010 to December 2011. A total of 1 773 bony and 740 cartilaginous fishes belonging to 26 species and 15 families were identified at the same sampling sites. Species richness was higher in the protected bay (Garrapatero) than in those open to fishing (Punta Rocafuerte, Saca Calzón). Blacktip sharks (Carcharhinus limbatus, n= 729), Thoburn's mullets (Mugil thoburni, n= 492), Peruvian mojarras (Diapterus peruvianus, n= 440), milkfish (Chanos chanos, n= 206) and the yellow fin mojarras (Gerres cinereus, n= 197) were the most common species across sites and season (cold and warm). The abundance of the most common species varied seasonally, with C. limbatus and C. chanos being more abundant in the warm season (December to April), and M. thoburni, C. limbatus and G. cinereus in the cold season (June to October). Temperature was the most important driver of abundance in C. limbatus and C. chanos, while salinity influenced Umbrina galapagorum. This study represents the first evaluation of the fish assemblage composition and dynamics in mangrove-fringed bays in the Galapagos Marine Reserve. Rev. Biol. Trop. 66(2): 674-687. Epub 2018 June 01.

Resumen Las bahías de manglar son ecosistemas muy variables que proveen hábitats críticos para especies de peces. En este estudio se evaluó los ensamblajes de peces de tres bahías de manglar (Punta Rocafuerte, Saca Calzón y Garrapatero) ubicadas en el sureste de la isla Santa Cruz, Reserva Marina de Galápagos. Usando redes de trasmallos iguales a los usados por la pesca artesanal, se llevaron a cabo un total de 108 salidas de campo entre enero 2010 y diciembre 2011. Un total 1 773 peces óseos y 740 peces cartilaginosos correspondiendo a 26 especies y 15 familias fueron capturados, identificados y liberados con vida. La riqueza de especies fue mayor en Garrapatero (sitio protegido) que en Punta Rocafuerte y Saca Cazón (sitios abiertos a la pesca). Las mayores capturas estuvieron representadas por el tiburón punta negra (Carcharhinus limbatus; n= 729), seguido la lisa rabo negro (Mugil thoburni; n= 492), la mojarra peruana (Diapterus peruvianus; n= 440), la diabla (Chanos chanos; n= 206) y la mojarra rayada (Gerres cinereus; n= 197). A pesar que éstas especies fueron consistentemente las más importantes a través de los sitios y temporadas (caliente y fría), se observó una mayor abundancia de C. limbatus y C. chanos durante la temporada caliente (enero a abril), y de M. thoburni, C. limbatus y G. cinereus durante la temporada fría (junio a octubre). La temperatura fue determinada como el factor más importante que influye en la abundancia de C. limbatus y C. Chanos, mientras la salinidad lo fue para Umbrina galapagorum. Este estudio representa una importante contribución para el entendimiento de la composición de los ensamblajes de peces en las bahías de manglar de la Reserva Marina de Galápagos.

Reef fish community in presence of the lionfish (Pterois volitans) in Santa Marta, Colombian Caribbean / Comunidad de peces arrecifales en presencia del pez león (Pterois volitans) en Santa Marta, Caribe colombiano

Objetive. Fish species community structure and benthic organisms coverage were studied in five localities in Santa Marta where the lionfish is present. Materials and methods. Abundance of fish species, including lion fish, was established using 30 m random visual censuses and video transects; trophic guilds were established according to available references. On the other hand benthic coverage was evaluated using the software Coral Point Count (CPCe) 4.0. Results. Families with higher species numbers were Serranidae, Labridae, and Pomacentridae. Lionfish abundances were low (2.6±2.1 ind/120 m²), but in any case Pterois volitans was observed as the eleventh more abundant species, surpassing species of commercial value such as Cephalopholis cruentata. Species that were found in larger numbers (>100, Thalassoma bifasciatum, Haemulon aurolineatum, Canthigaster rostrata, Abudefduf saxatilis, Chromis cyanea, and Stegastes partitus) were mainly invertebrate eaters, planctivores, and territorial herbivores. Coral coverage showed higher coral percentages in Chengue (69.9%) and Cinto (27.4%), larger sponge percentages in Morro (32.7%); Isla Aguja and Remanso showed the larger figures for abiotic substrate (41.6 and 37%, respectively); corals, sponges, and gorgonians were the components best explaining fish community, but not for the lion fish, which inhabit all studied reef formations. Conclusions. Lion fish is ranked between the 20 more abundant species, with none commercially important species larger, hence no species may qualify as a natural control. Lion fish has as well become a relatively abundant species in Santa Marta reefs, independent of benthic coverage.

Objectivo. Se estudió la estructura de especies de la comunidad íctica y se evaluó la cobertura de organismos bentónicos en cinco localidades en Santa Marta, Colombia con presencia del pez león. Materiales y métodos. Se estimó la abundancia a través de censos visuales y video transectos de 30 m y se estableció el gremio trófico de cada especie según literatura. El sustrato se cuantificó con el software Coral Point Count (CPCe) 4.0. Resultados. Las familias con más especies fueron Serranidae, Labridae y Pomacentridae y, aunque su abundancia promedio fue baja (2.6±2.1 ind/120 m²), Pterois volitans fue la undécima especie más abundante, superando a peces comerciales como Cephalopholis cruentata. Las especies más abundantes fueron invertívoros, planctívoros y herbívoros, tales como Thalassoma bifasciatum, Haemulon aurolineatum, Canthigaster rostrata, Abudefduf saxatilis, Chromis cyanea y Stegastes partitus. Se encontró mayor porcentaje de coral en Chengue (69.9%) y Cinto (27.4%) y de esponjas para Morro (32.7%); para Isla Aguja y Remanso predominó el componente abiótico (41.6 y 37%, respectivamente). Corales, esponjas y gorgonias fueron los componentes que mejor explicaron la comunidad íctica, aunque no para el pez león que habita todas las formaciones arrecifales. Conclusiones. El pez león se ubica entre las 20 especies de peces más abundante, con ninguna especie de importancia comercial en los sitios muestreados que lo supere en talla y que pudiera ser un control natural del invasor. Igualmente, se ha convertido en una especie relativamente abundante en los arrecifes samarios sin importar los atributos del fondo.

Amphidinolide P from the Brazilian octocoral Stragulum bicolor

Abstract Dinoflagellates are an important source of unique bioactive secondary metabolites. Symbiotic species, commonly named zooxanthellae, transfer most of their photosynthetically fixed carbon to their host. The mutualistic relationship provides the organic metabolites used for energy production but there are very few reports of the role of the dinoflagellates in the production of secondary metabolites in the symbiotic association. Corals and other related cnidarians are the most well-known animals containing symbiotic dinoflagellates. In the present paper we describe the isolation of amphidinolide P (1) from the octocoral Stragulum bicolor and its prey, the nudibranch Marionia limceana, collected off the coasts of Fortaleza (Ceará, Brazil). The coral extracts also contained 3-O-methyl derivative (2) of amphidinolide P, together with minor compounds still under investigation. Amphidinolides have been so far reported only in laboratory cultures of Amphidinium sp., thus compounds 1 and 2 represents the first identification of these polyketides in invertebrates. The finding proves the possibility to isolate amphidinolides from a natural symbiosis, enabling further biological and biotechnological studies.

Bibliografía sobre organismos, ambientes y procesos marinos y atmosféricos en Bahía Culebra, Pacífico norte, Guanacaste, Costa Rica (1922-2012) / Bibliography on marine organisms, environments, and oceanographic and atmospheric processes in Bahía Culebra, north Pacific, Costa Rica (1922-2012)

Bibliography on marine organisms, environments, and oceanographic and atmospheric processes in Bahía Culebra, north Pacific, Costa Rica (1922-2012). Bahía Culebra is located on the north Pacific coast of Costa Rica. It is a seasonal upwelling area, rich in marine ecosystems and organisms, and the main tourist development area in the country. Here, I compiled and analyzed a list of 182 publications in scientific journals, and 23 thesis, reports and books in which marine organisms, environments and marine and atmospheric processes from Bahía Culebra or in which the Bay are mentioned is presented and analyzed. The majority of the publications, starting with a paper from 1922 on a polychaete worm, are on biodiversity and ecology. The are no publications on some environments, for example the benthonic fauna of soft bottoms, or on some taxa, for example, flat worms. More work is needed on fisheries and management of the organisms and environments of Bahía Culebra.

Bahía Culebra se locoaliza en la parte norte de la costa Pacífica de Costa Rica. Es una región de afloramiento estacional, rica en ambientes y organismos marinos, y además, la zona de mayor desarrollo turístico del país. En este trabajo compilo y analizo una lista de 182 publicaciones en revista científcas y 23 tesis, informes y libros sobre organismos, ambientes y procesos marinos y atmosféricos en Bahía Culebra o donde se menciona la Bahía, se presentan y analizan. La gran mayoría de los trabajos, empezando en 1922 con la descripción de un poliqueto, son sobre biodiversidad y ecología. Faltan trabajos sobre algunos ambientes de la bahía, por ejemplo, el bentos de los fondos blandos, y grupos de organismos, por ejemplo, sobre gusanos planos de vida libre. Faltan investigaciones sobre pesquería y manejo de los organismos y ambientes marinos de la Bahía.