Caribbean Sea

An inventory of the main jellyfish distributed in different locations of Nueva Esparta state was made, during years 2009 to 2012. The jellyfish were observed and collected during fishing operations, diving (snorkeling and SCUBA) and stranded on the beach, collecting a total of 30 specimens.. The Class Scyphozoa presented the highest species richness with four families and four species; on the other hand, the Class Cubozoa was represented by two species, while one species was representative of the class Hydrozoa.

High-elevation tropical grassland systems, called Páramo, provide essential ecosystem services such as water storage and supply for surrounding and lowland areas. Páramo systems are threatened by climate and land use changes. Rainfall generation processes and moisture transport pathways influencing precipitation in the Páramo are poorly understood but needed to estimate the impact of these changes, particularly during El Niño conditions, which largely affect hydrometeorological conditions in tropical regions. To fill this knowledge gap, we present a stable isotope analysis of rainfall samples collected on a daily to weekly basis between January 2015 and May 2016 during the strongest El Niño event recorded in history (2014-2016) in two Páramo regions of Central America (Chirripó, Costa Rica) and the northern Andes (Cajas, south Ecuador). Isotopic compositions were used to identify how rainfall generation processes (convective and orographic) change seasonally at each study site. Hybrid Single Particle Lagrangian Integrated Trajectory model (HYSPLIT) air mass back trajectory analysis was used to identify preferential moisture transport pathways to each Páramo site. Our results show the strong influence of northeast trade winds to transport moisture from the Caribbean Sea to Chirripó and the South American low-level jet to transport moisture from the Amazon forest to Cajas. These moisture contributions were also related to the formation of convective rainfall associated with the passage of the Intertropical Convergence Zone over Costa Rica and Ecuador during the wetter seasons and to orographic precipitation during the transition and drier seasons. Our findings provide essential baseline information for further research applications of water stable isotopes as tracers of rainfall generation processes and transport in the Páramo and other montane ecosystems in the tropics.

Costa Rica's Caribbean coastline is the result of a complex tectonic setting coupled with dynamic geological, climatological, hydrological and ecological processes. Despite their importance in risk prevention and in land use planning, geomorphological maps at detailed scales are scarce in Costa Rica. A geomorphology map of 210 km of the Caribbean coastline was produced at a scale of 1: 25,000 with a 1: 50,000 scale output map. Eleven landforms were mapped and described based upon their morphogenesis (i.e. tectonic, volcanic, fluvial and/or coastal). This work is an important base for coastal management, and is a compilation of the best existing knowledge of the Caribbean coast of Costa Rica. ARTICLE HISTORY

Aruba is one of the most densely populated islands in the Caribbean. However, very little is known about its cetaceans. In 2010 and 2011, a total of 19721 km (1686 h) boat-based surveys over nearshore transects resulted in 117 positively-identified sightings comprising eight species. New records are also added for one of three previously-documented species. Five additional species were documented from strandings or reports by others. This brings the total number of cetacean species identified in Aruban waters to 16, of which nine are authenticated here for the first time. Atlantic spotted dolphin (Stenella frontalis (N ¼ 59) and bottlenose dolphin (Tursiops truncatus) (N ¼ 33) were the most frequently observed species, with sightings of both year-round, followed by spinner dolphin (S. longirostris) and false killer whale (Pseudorca crassidens). Additional species recorded are pantropical spotted dolphin (S. attenuata), striped dolphin (S. coeruleoalba), common dolphin (Delphinus capensis), rough-toothed dolphin (Steno bredanensis), short-finned pilot whale (Globicephala macrorhynchus), killer whale (Orcinus orca), Risso's dolphin (Grampus griseus), humpback whale (Megaptera novaeangliae), Bryde's/Eden's whale (Balaenoptera brydei/edeni), sperm whale (Physeter macrocephalus) and an unidentified beaked whale (Mesoplodon sp.). All cetaceans were sighted within 22 km of the coast in relatively shallow waters. Sighting rate was low (0.69 cetacean sightings per 100 km). Sightings of calves and neonates indicate that Aruba may be a nursing or breeding area for some species. The presence of several species of cetaceans in Aruba's coastal waters year-round indicates that status and threat assessments are needed to protect them.

Although sponges are important components of benthic ecosystems of the Caribbean Sea, their diversity remained poorly investigated in the Lesser Antilles. By organizing a training course in Martinique, we wanted both to promote taxonomy and to provide a first inventory of the sponge diversity on this island. The course was like a naturalist expedition, with a field laboratory and a classroom nearby. Early-career scientists and environmental managers were trained in sponge taxonomy. We gathered unpublished data and conducted an inventory at 13 coastal sites. We explored only shallow water habitats (0–30 m), such as mangroves , reefs or rocky bottoms and underwater caves. According to this study, the sponge fauna of Martinique is currently represented by a minimum of 191 species, 134 of which we could assign species names. One third of the remaining non-identified sponge species we consider to be new to science. Martinique appears very remarkable because of its littoral marine fauna harboring sponge aggregations with high biomass and species diversity

Pteropods and heteropods (holoplanktonic gastropods) are an important component of the modern oceans; however, detailed
information on their distribution in the fossil record is often based on poorly preserved specimens. This study presents the
micropaleontological analysis of three exceptionally well-preserved Late Pleistocenemarine sediment cores from the eastern Caribbean
Sea, westernMediterranean Sea and the Indian Ocean. This study presents the first stratigraphical record of heteropods in the Caribbean
Sea and extends the known zonation of pteropods in the Mediterranean Sea. Distributions of pteropods, heteropods and planktonic
foraminifera are presented with abundance and species richness data, as well as stratigraphical dates inferred from the oxygen isotope
stratigraphy, argon-argon dating and biostratigraphy. The findings of this study greatly improve our understanding of holoplanktonic
gastropod stratigraphy and ecology. Results reveal that the geographical range of heteropods, thought to be restricted to sub-tropical
warm waters,may be much greater, including waters of sub-polar temperature. Heteropods were also found to be surprisingly abundant,
potentially representing a more important part of the ocean food web than previously thought. Analysis revealed two species of
holoplanktonic gastropod that are previously undescribed and indicate that the pteropod Heliconoides mermuysi (Cahuzac and Janssen
2010), known exclusively from the Moulin de Cabanes (Miocene),may have lived in theCaribbean Sea and Indian Ocean as recently as 4
kyr ago. These findings highlight the urgent need for increased research on holoplanktonic gastropods. The threat that current climate
change and ocean acidification poses, particularly to the delicately shelled forms, means that some species may become extinct before
they have even been fully ‘discovered’

The family Nereididae includes more than 500 polychaete species described worldwide, and includes species common in many benthic environments, but some other species may tolerate freshwater or can even thrive in humid substrates in tropical forests. In estuarine environments, nereidid polychaetes can be abundant and relevant as a food source for resident or migratory birds. Laeonereis culveri (Webster, 1879) is a common estuarine species found in tropical and subtropical Atlantic American shores and was described from New Jersey; its median and posterior parapodia have upper notopodial ligules usually longer than the lower ones, and the latter are parallel to the notaciculae throughout the body. L. culveri distribution is from Connecticut to central Argentina; however, this wide distribution might be due to the inclusion of several other species as junior synonyms, despite that some morphological differences were found between them. One of such species is L. nota (Treadwell, 1941), that was described from Texas; its parapodia have notopodial ligules of about the same size, and the lower ones are oblique to the notaciculae. In order to clarify the differences between these two species, and to define which inhabits the Northwestern Caribbean region, topotype materials from these two species and specimens from Chetumal Bay were collected, and their morphological features were compared. Our results indicated that L. culveri and L. nota are different species and that the latter is found in Chetumal Bay. On the basis of mature specimens, L. culveri is hereby restricted to the Northern Gulf of Mexico and Northwestern Atlantic Ocean, and L. nota is reinstated and its distribution extends from Texas, in the Gulf of Mexico to Chetumal Bay, in the Northwestern Caribbean Sea. A key to identify all species in Laeonereis Hartman (1945) is also included. Rev. Biol. Trop. 64 (1): 189-201. Epub 2016 March 01.

Sixteen years of sea surface temperature (SST, 1994-2009) were used to characterize the southern Caribbean upwelling system. This system extends from 61-75.51W and 10-12.51N, with 21 upwelling foci clustered in seven groups differentiated by their SST cycles. Two of those groups had the strongest coastal upwelling: the 'eastern area' (63-651W) and the 'western area' (70-731W). The literature reports that the eastern and western upwelling areas hold 78% and 18% of the small pelagic biomass within the upwelling system, respectively. We looked into variations of the upwelling dynamics in those areas using seasonal cycles of satellite SST, chlorophyll-a (Chl) and sea-wind, as well as climatological hydrographic data from the World Ocean Atlas. Comparing their annual averages, the eastern area featured the lowest SST (25.24 1C) and the highest Chl (1.65 mg m −3); it has moderate wind intensity (6.12 m s −1) and shallower 22 1C isotherm (85 m). The western area had stronger winds (8.23 m s −1) but deeper 22 1C isotherm (115 m), slightly higher SST (25.53 1C) and moderate Chl (1.15 mg m −3). The upwelling in the eastern area was more prolonged than in the western area (SST o26 1C during 8.5 and 6.9 months, respectively). According to the 'optimal environmental window' theory, small clupeoid recruitment is a dome-shaped function of the upwelling intensity, turbulence and SST, with an optimum wind speed around 5-6 m s −1. The eastern upwelling area wind speed is close to this optimum value. The western upwelling area shows much higher wind speed that causes high level of turbulence and strong offshore transport that could hinder small pelagics recruitment in that area.

The tropics are characterized by a variety of atmospheric and oceanic systems dominated by multi-scale interaction processes. This is Part I of a two-part review study on climate and climate variability of the Eastern Tropical Pacific (ETP). Here, the mean fields of incoming short wave radiation, surface energy fluxes, sea surface temperature, sea level pressure, salinity, wind patterns at 10m height, wind stress curl, precipitation, and evaporation are analyzed and synthetized using available data including that from the last decade. Given the strong interaction between the ETP and Caribbean Sea-Atlantic Ocean, mean field discussions are presented for two different domains, a relatively large domain from 24° S-36° N and between 129° W-17° W, and a smaller domain embedding only the Caribbean Sea and the easternmost part of the ETP. Most results on the climate of these two regions can be used as the base line for climate change studies. Interannual variability of tropical cyclones is also investigated over the domain of the latter two basins in the smaller domain. The study is complemented with a short review of some low frequency modes, such as, El Niño-Southern Oscillation, the Pacific Decadal Oscillation, and the Atlantic Multi-decadal Oscillation. Such low-frequency modes are known to modulate regional systems, including tropical cyclone frequency. Rev. Biol. Trop. 64 (Suppl. 1): S1-S22. Epub 2016 February 01.

RESUMEN: El pulpo común, Octopus vulgaris, (CUVIER, 1797) constituye un recurso pesquero de gran valor, además de desempeñar un rol significativo en la dinámica trófica de los ecosistemas donde está presente, por lo cual resulta importante hacer estudios parasitológicos sobre él, particularmente escasos en Venezuela. Cincuenta y dos ejemplares adultos de pulpo común, provenientes de actividades pesqueras del noreste de la Isla de Margarita, fueron analizados para conocer su condición sanitaria. Ante la presencia de cuerpos iridiscentes en diferentes órganos, se tomaron muestras de los tejidos, se fijaron en solución de Bouin y se procesaron histológicamente. Su estudio histopatológico demostró la presencia del coccidio Aggregata sp., no registrado previamente en aguas venezolanas. Entre las fases vitales observadas del parásito, las más significativas taxonómicamente fueron los ooquistes, los cuales mostraron forma subesférica a ovoidal, superficie lisa y un diámetro promedio de 614,3 mm (360-1060 m), así como los esporoquistes, esféricos, los cuales medían 12,3 mm en promedio (11,2-14 mm), conteniendo de 4 a 12 esporozoitos vermiformes, con una moda de 6. Se discuten algunos aspectos taxonómicos, ecológicos y patológicos del hallazgo.

Seagrass meadows evolved in the presence of disturbances and have a wide variance in recovery rate that largely follow a trajectory of re-colonization and succession to pre-disturbance levels. Invasive species may gain a foothold within native seagrass beds after space is opened by disturbances that reduce seagrass cover. Here we use shoot density monitoring data to describe growth of the invasive seagrass Halophila stipulacea in Caribbean bays over a 5-year period and conduct a series of experiments using a combination of mesocosm, seagrass removal plots, and field measurements to quantify vegetative fragment survivorship and recovery after benthic disturbance. Shoot density increased rapidly in invaded bays, reaching average densities of approximately 600 shoots/m 2 within 5 years of establishment. Seagrass cover was estimated to recover to pre-disturbance level 17-31 weeks after removal from vegetative propagation of neighboring plants outside the treatment plot. Mesocosm experiments found floating and settled fragments as small as 2 cm in length and containing at least one vertical shoot survived the 4-day trial and increased in both length and biomass. Empirical evidence here demonstrates that H. stipulacea is highly resilient to small-scale disturbance which we suggest is having a transformative impact on Caribbean seagrass communities.

La producción primaria diaria del fitoplancton fue estimada en la estación serial del programa CaTS (Caribbean Time-Series Station, 17° 36’N, 67° 00’0) mediante incubaciones en un fotosintetrón usando radiocarbono, 14C. Generamos curvas de irradianza contra la tasa de fotosíntesis (curvas P-E) para obtener los parámetros fotosintéticos: alfaB, betaB, y PBs.
Determinamos el valor de la constante de atenuación vertical, Kd (PAR), y la profundidad de la capa fótica mediante perfiles de irradianza descendente en la banda de los 400-700 nm, Ed
(PAR,z). Se registró la fluorescencia de la clorofila-a in situ para generar un perfil vertical de la biomasa de fitoplancton distribuida en la columna de agua. La irradianza PAR en la superficie del mar, Ed (PAR,0), fue modelada mediante estimados de la cubierta de nubes tele detectada
por satélites (International Satellite Cloud Cover Project). Modelamos la propagación vertical de la irradianza incidente en superficie utilizando el coeficiente de atenuación vertical de la luz difusa, Kd(PAR,z). Se integró numéricamente el perfil de la tasa de fotosíntesis hasta una profundidad de 200 m, limitando la integración a las horas de luz disponibles para fotosíntesis.
La producción integrada (PP) osciló entre 62 y 943 mg C m-2 d-1. La producción anual es alrededor de 171 g C m-2 año-1. La trayectoria anual de PP muestra una distribución con
valores elevados en: marzo-abril, julio y octubre. Esta estacionalidad coincide con la observada en la serie de tiempo de clorofila-a tele detectada por SeaWiFS en una banda entre los 15.6-17.6° N. El aumento en la producción primaria en marzo-abril esta asociado a la mayor disponibilidad de luz al fitoplancton profundo, a la influencia de aguas dispersas del Río Amazonas y a la presencia de fitoplancton con parámetros fotosintéticos favorables. El máximo de octubre se explica por la influencia del Río Orinoco pero el máximo de julio no parece estar asociado a influencia de los ríos. La estación CaTS muestra oscilaciones mayores en PP que no se observan en otras estaciones oligotróficas como BaTS y HOT.

Internal tides of near-semidiurnal frequencies were observed in October 2000 at the ADCP1 station located in oceanic waters (18° 17.478’ N, 67° 48.155’ W), about 10 nautical miles to the NNE of Mona Island with a depth of 481 m. The maximum observed height (crest to trough) in the euphotic zone was 26 m. The presence of a shallow pycnocline (40 m) and high Brunt-Väisälä frequencies were due to maximum influence of the Orinoco River on the Mona Passage waters at this time of the year. These conditions facilitated the propagation of the internal tide throughout the middle of the euphotic zone. Maximum concentrations of chlorophyll-a (1.2 mg Chl-a m-3) occurred during high upward velocities (> 40 m h-1). Phytoplankton was displaced upward to a zone above the pycnocline receiving higher light intensities. Additionally, increases in vertical eddy diffusivity above 6 x 10-3 m-2 s-1 were observed one hour before the arrival of the internal tide trough. Soon after that, increments in primary productivity of the order of 0.05 mg C m-3 h-1 were measured. The advection of phytoplankton by strong upward currents into a layer of higher irradiance, and increments in vertical eddy diffusivity, were responsible for distorting the typical V-shaped spatial-temporal pattern of primary productivity. Higher values of primary productivity were observed near the wave trough, than those observed during periods of maximum solar irradiance at noon. Significant changes in the attenuation coefficient (from 0.03 m-1 to 0.05 m-1) for the following SeaWiFS bands: 412, 443, 490 and 512 nm corresponded to events of maximum upward velocities and higher diffusivity. These processes seem to be easy to detect in oceanic waters, out of the influence from high nutrient load waters due to rivers.

To determine the coral reef morpho-functional structure of San Andrés, regarding functional benthic diversity and fish (Lutjanidae), we evaluated the condition of the coral structure on the leeward side of the island, which is an area impacted by tourism, through diving and fishing. Three sampling sites were evaluated during two years recording the distribution of benthic organisms, environmental variables and Snappers density (Lutjanidae). A low density of Lutjanus jocu and Ocyurus chrysurus was found, with a high density of juveniles of L. apodus and L. mahogoni, which showed a preference for reefs with submassive and brain corals. Algae especially Macroalgae and octocorals were those with the greatest coverage in the reefs, followed by inert substrates, while corals were represented by species with a wide distribution such as Agaricia agaricites and Porites astreoides. Octocorals correlated negatively with stony corals and that the most widespread fragile corals were the finger. We concluded that there is a higher density of mainly juvenile snappers where there is a greater variety of coral morpho-functional groups, and not necessarily in sites with greater coral coverage. Also, adult snappers were associated with octocoral zones. This shows that morpho-functional diversity is a crucial factor in the permanence of snappers.

El 8 de Agosto del 2014 a las 12:53 LST (Hora Local) ocurrió un meteotsunami con una altura de 29.9 cm (0.98 ft) en el Puerto de Fajardo, Puerto Rico. Este es el evento de mayor altura registrado hasta el día de hoy (vea Tabla 1). El evento está asociado al paso de una onda tropical por el área de Puerto Rico. Fue generado por un pulso en la presión atmosférica de 0.4 mb.  El pulso se desplazó a 35 MPH desde el ESE, discurrió unos 50.8 km en un trayecto a lo largo de la plataforma insular entre Vieques y Fajardo. El acoplamiento entre el pulso atmosférico y la ola larga barotrópica facilitó que durante el trayecto la resonancia de Proudman (1929) incrementara la amplitud de la ola, desde -0.4 cm hasta 1.8 cm. Luego en el Puerto de Fajardo, nuevamente la amplitud del meteotsunami aumentó 13.15 cm debido a la segunda resonancia con el Puerto de Fajardo. Para alcanzar una amplitud final igual a 14.95 cm.

Macroalgae of the marine subtidal area of the Miranda state, Venezuela Marine macroalgae have an important role in the ecology of aquatic ecosystems because they contribute to primary productivity and provide food and habitat for many species. The study of these communities in the Miranda state has been scarce and they have mainly focused on the intertidal zone, so an inventory of macroalgae in the subtidal zone between Chirimena and Puerto Francés was considered. To do this, samplings were done monthly from June 2014 to March 2015 at twelve randomly selected stations between 5 and 25 m deep. Macroalgae were identified in the laboratory using microscopes and specialized literature. A total of 119 species of macroalgae were identified, dominated by the Rhodophyta phylum, followed by Ochrophyta phylum. Two increases in species richness were observed during the study time: the first of them was associated with the intensity of the trade winds during the first months of the year which promote upwelling in the Venezuelan coast. This was evidenced by the presence of some indicator species of this phenomenon. The second increase occurred at the beginning of the rainy season followed by a decrease during the months with maximum rainfall. With this inventory, a total of 45 unreported species for the Miranda state, and Gayliella taylorii, Gayliella fimbriata and Rhodymenia divaricata species for the Venezuelan coast were registered.

RESUMEN: Las macroalgas marinas tienen un papel importante en la ecología de los ecosistemas acuáticos, ya que además de contribuir con la productividad primaria, proporcionan alimento y hábitat a muchas especies. Los estudios de estas comunidades en el estado Miranda han sido escasos y enfocados fundamentalmente en la zona intermareal, por lo que se planteó realizar un inventario de las macroalgas de la zona submareal entre Chirimena y Puerto Francés. Para ello, se realizaron muestreos mensuales desde junio de 2014 hasta marzo de 2015 en doce estaciones seleccionadas aleatoriamente entre 5 y 25 m de profundidad. La identificación de las macroalgas se realizó en el laboratorio con el uso de microscopios y claves especializadas. Se identificaron 119 especies de macroalgas dominadas por el phylum Rhodophyta, seguido por el phylum Ochrophyta. Se observaron dos aumentos del número de especies durante el periodo de estudio. El primero asociado a la intensidad de los vientos alisios durante los primeros meses del año, los cuales promueven la surgencia costera, y que se evidenció con la presencia de especies indicadoras de este fenómeno. El segundo aumento del número de especies ocurrió al principio de la época de lluvias, con una disminución posterior durante los meses con máximas precipitaciones. Con este inventario, se contribuyó con 45 especies no reportadas para el estado Miranda y las especies Gayliella taylorii, Gayliella fimbriata y Rhodymenia divaricata para la costa venezolana.

This study presents the first observation of a tsunami induced by an atmospheric disturbance, this phenomenon is known in the literature as a meteotsunami. The meteotsunami was small scale and no damage was reported in the ports. On August 16, 2011 between 12:24 and 21:18 AST, the NOAA tide gauges registered a marked increase in the height of the coastal seiches in several ports and bays along 120 miles of the Caribbean coast in Puerto Rico; in the following locations: Puerto de Yabucoa, Santa Isabel, Magueyes Island, Salinas Bay, Puerto Real, Puerto de Mayagüez and in the west of Mona Island. The seiches with the highest height were recorded in Bahía Salinas and in Puerto Real with heights of 0.61 ft (18.5 cm) and 0.48 ft (14.6 cm), respectively. The amplitudes of meteotsunami in these two places were 0.305 ft (9.3 cm) and 0.24 ft (7.3 cm), surpassing by some 9 and 11 times the RMS amplitude of these localities. Even in Bahia Salinas the height of the wave exceeded the vertical range of the tide. The meteotsunami was excited by a pulse at atmospheric pressure of 0.7 mb and 2 ½ hours later by a second pulse of 1.4 mb. Increases in atmospheric pressure were immediately followed by a line of strong winds in gusts, which reached up to 37 knots (42.6 MPH). These events are associated with the passage of an extensive tropical wave over the waters south of Puerto Rico. According to the National Hurricane Center in Miami, the tropical wave was moving westward at about 20 MPH. Meteorological stations along the coast recorded the passage of pulses, which moved westward at an average speed of 35.5 MPH (15.8 m s-1). The tide gauges recorded the excitement of the seiches after the passage of the first pulse in the barometric pressure on each of the locations. The pulses excited seiches progressively throughout each station, making it possible to calculate the propagation speed between 28.6 MPH (12.7 m s-1) and 35.3 MPH (15.7 m s-1), equivalent to the local velocities of a long wave propagating in waters with depths between 16.5 m and 25.1 m. Assuming that the local longwave velocity is on average 32 MPH (14.2 m s-1), the mathematical ratio between the velocity of the atmospheric pulse (0.7 mb) and the long wave velocity is equivalent to a Froude number (Fr) equal to 1.11. This value suggests Proudman resonance between the atmospheric disturbance and the long wave when they travel on the waters of the insular platform, amplifying the first wave by 3 cm and the second wave by 6 cm. The final amplitude of the meteotsunami suggests that there was amplification due to resonance in the harbor or bay. Immediately after the passage of the second pulse, the currents increased their magnitude by 20 cm s-1 towards the west at a depth of 1 m and 4 m.

The interstitial cyclopoid copepod Neocyclops ferrarii Rocha, 1995 was found in samples obtained from littoral areas of Rodadero Bay, northern Colombia. The specimens from Colombia share the diagnostic features of N. ferrarii presented in the original description. However, the Colombian specimens show some degree of variation with respect to the type material in: 1) the number of teeth in the labrum; 2) the length of outer exopodal spine on female leg 5; 3) the relative length of the mandibular palp setae; 4) length/width ratio of caudal rami; 5) the length ratio of caudal setae VI/III; 6) the length ratio of caudal setae VII/VI; 7) the male body size; 8) the male caudal rami length/width ratio; 9) This is the second record of this species after its original description from Belizean waters. In the Caribbean region N. ferrarii most closely resembles N. vicinus Herbst, both of them bear an antennary exopod, a 12-segmented female antennule, P3ENP3 armature formula 3,III, but can be separated from the latter by difference in the length/width ratio of the female caudal ramus, the length ratio of caudal setae VI/III, the length ratio of caudal setae VII/VI, the male body size, the number of segment of P4ENP, the armature details of mandibular palp and the number of segments of male P5. This is the second species of Neocyclops recorded from Colombia and represents a distributional range expansion of N. ferrarii in the Caribbean Basin.

Nocturnal variations of zooplankton abundance and hydrographic conditions were examined at three locations (centre, north shore and south shore) in Phosphorescent Bay, Puerto Rico, from May 1992 through April 1993. Seven taxa accounted for approximately 96% of the annual mean zooplankton abundance: Oithona spp. (43·5%), Acartia tonsa
(31·5%), copepod nauplii (8·8%), Paracalanus spp.(6·7%), gastropod veligers (2·5%), larvaceans (1·7%) and Pseudodiaptomus cokeri (1·6%). Copepods dominated numerically throughout the year and comprised 94·3% of total zooplankton. Higher abundance of zooplankton (mean&1 SD=252 259&176 797 individuals m"3) was associated with cool water temperatures (24·9–27·4 )C) and dry conditions (0·3–2·9 cm precipitation/month) which prevailed between December and March relative to the period between April and November (warm/wet season) (mean&1 SD=59 773&26 861 individuals m"3), when temperature and precipitation were higher (27·3–30·3 )C, 3·1–20·6 cm month"1). Fluctuations of zooplankton populations, particularly copepods, followed progressive increments in chlorophyll a concentrations. This abundance pattern was consistent at the three sampling stations. Zooplankton abundance was higher on the north shore of the bay. The taxonomic composition of zooplankton was similar at the sampling stations studied.

Recently, 250-m resolution MODIS images acquired by the Earth Observing System Terra and Aqua Satellites during sunglint conditions allowed us to survey high-frequency nonlinear internal solitary wave occurrences on a near-global scale . It is possible to detect internal solitons packets leaving the generation area during fortuitous conditions: minimum cloud cover, near-specular reflectance pattern of sunlight off the ocean surface (sunglint) and strong oceanic stratification. On a few days of September 2012 all these favorable conditions concurred allowing us to track the movement of solitons packets across the Caribbean Sea. Some of the packets traveled 540 km from Aves Ridge toward Puerto Rico, exciting coastal seiches as was hypothesized by Chapman and . Others traveled toward Curacao and the Netherland Antilles. Two sets of sequential images were analyzed. The first set covers SEP 01-04 2012 (YD 245-YD 248) and the second set covers SEP 17-20 2012 (YD 261-YD 264). September is the peak month of the hurricane season, but luckily most of the tracks were far from the Caribbean Sea and the cloud cover was notably reduced. The first MODIS image shows four solitons packets west from Aves Ridge, they are named: Lopez245, Hollander245, Harris and the farthest is Forel. The suffix corresponds to the image yearday. For example, Lopez246 is the same soliton packet, but one day later. The traveled distance was measured by georefencing the images in Google Earth and using the application called ruler. Distance traveled measurements were calculated using only the lead soliton of each packet. We obtained 87 km for Lopez246. The time of each image comes from the metadata file. Time interval between successive images is 78300 seconds. Dividing travel distance by time interval we obtained a soliton speed of 1.11 m/s. displays the calculated lead soliton celerity for Lopez and Hollander packets. A simple visual inspection of the sequential images shows an evolution within the wave packets. The solitons separation distance (SS) increases the wave packet width (WPW). The ratio of these two physical parameters, SS/WPW, follows a logarithmic curve for the Harris Packet ). If we plot this ratio against the waves source distance we get a useful linear trend ). Plotting the linear trends for each wave packet (of the first set) against the lead soliton distance allowed us to get a clear picture of packet evolution, as they move away from the source. The trend lines slope have a tendency to reduce their values as the packets move away from Aves Ridge ). Plotting the slopes of the trend lines against the lead soliton distance from Aves Ridge shows a logarithmic decrease in the slope value, as we move away from the source ). This evidence supports that the spreading of the solitons occurred just after passing over the Aves Ridge. The origin point for our distance measurements was selected at the southern tip of the prominent crest, the origin coordinates were: 14° 03' 12" N, 63° 36' 35" W. There are several MODIS images of internal solitary waves about 10-20 km east of this location moving west toward our origin position, these images show one or two solitary waves but not packets (see last MODIS image of this paper). These waves could be a lee wave before been released or a solitary wave generated at other ridge crest about 100 km East. Just after the solitary waves passed over the Aves Ridge the soliton packets appeared. It is interesting to note that the horizontal scale of soliton packet separation is of the order of 100 km. The second set of images shows packet Apel moving SW (237°) toward Curacao and the Netherland Antilles and packet Chapman moving NW (294°) toward Puerto Rico and the Dominican Republic. From the image analysis we obtained a speed of 0.81 m/s for the lead soliton of packet Apel. The lead soliton speed of packet Chapman ranged between 1.22 m/s and 1.75 m/s ( ). The estimated time of arrival (ETA) of the soliton packet to Puerto Rico is shown on . The true arrival time was mark as the start of large seiche oscillations (> 0.4 feet) in the tidal record of Magueyes Island ( ). Our ETA's were offset by 11 hours from the true arrival time . One day later, a second package arrived and excited more large amplitude oscillations. Assuming an average package separation distance of 92.5 km, it is possible to estimate a speed of 0.97 m/s. In conclusion, our analysis of the second set of MODIS images revealed that soliton packages speeds ranged between 1.22 to 1.75 m/s, equivalent to a travel time of 3.6 to 5.1 days to reach Isla Magueyes, Puerto Rico. Top: Modis Image: LesserAntilles.2012245.aqua.721.250m (01/SEP/2012 17:30 UTC) Bottom: Modis Image: LesserAntilles.2012246.terra.721.250m (02/SEP/2012 15:15 UTC).

The Sardinella aurita fishery off northeastern Venezuela, region of seasonal wind-driven coastal-upwelling, accounts for 90% of the Caribbean Sea small pelagic catch. This law-protected artisanal fishery takes place up to ~10 km offshore. The spatial distribution, number of schools, and biomass of S. aurita were studied using eight hydro-acoustic surveys (1995-1998). The study included the analysis of satellite-derived sea surface temperature and chlorophyll-a. Surveys were grouped by strong, weak, and transitional upwelling seasons. Relationships between these observations were analyzed using Generalized Additive Models. Results show that during the primary upwelling season (January-May) sardines were widely distributed in upwelling plumes that extended up to 70 km offshore. In the other hand, during the weak upwelling season (September-October) higher sardine densities were found within 10 Km off the coastal upwelling foci. The number of small pelagic schools was directly correlated with small pelagic densities; however, regardless of the season, higher numbers of small pelagic schools were always closer to the shoreline, especially during warm conditions. These two behaviors increase the availability and catchability of sardines for the artisanal fishery during the warm season, regardless of the total stock size.

The tiger shrimp (Penaeus monodon) is an Indo-Pacific species. Its global production between 1970 and 1980 exceeded all other shrimp
species, which favored its introduction and cultivation outside its natural range in several countries of Africa, Europe, USA and South
America. It is currently found in the coast of the Atlantic Ocean (Mexico, United States, Puerto Rico, Brazil, Guyana, Venezuela and
Colombia). Despite the risk involved, no studies have been conducted to evaluate their impact as a possible invasive species and
their genetic condition. This study evaluated the genetic status and population origin of P. monodon in the northernmost Colombian
Caribbean, analyzing the mitochondrial DNA control region (mtDNA-CR). 16 individuals were randomly collected from Golfo
de Salamanca and 342 original Indo-Pacific sequences were obtained from GenBank. Parameters of genetic diversity and genetic
relationships were analyzed. These results were a total of 358 sequences compared and 303 haplotypes identified. Three haplotypes
were identified in the Colombian population. This results showed lower genetic diversity compared with Indo-Pacific populations.
These haplotypes were closely related to those found in samples from the Philippines and Taiwan. We discuss the need to create
a regional network to characterize the established populations in the Great Caribbean, with the purpose of inferring colonization
processes and the establishment of management measures.

Este estudio demuestra que los eventos de seiches costeros extremos en Isla Magueyes, en el suroeste de Puerto Rico son excitados por una actividad intensa de olas solitarias internas de tamaño mayor que se generan en la Cresta Submarina de Aves luego de la evolución no-lineal de una marea interna semidiurna M2 que se enfrenta a una corriente zonal positiva. Condiciones astronómicas favorables (coincidencia de sizigia, perigeo y cruce del Ecuador Celeste) no son suficientes para generar una actividad mayor. Es necesaria la presencia de una corriente contraria a la propagación de la marea interna semidiurna. Esta corriente se manifiesta cuando hay vorticidad ciclónica entre la isla de Martinique y la Cresta Submarina de Aves. El lado sur del vórtice ciclónico genera la corriente zonal positiva dentro del corredor de la marea interna semidiurna. Presentamos tres eventos concretos que cumplen esa misma condición oceanográfica.

Un evento extraordinario de seiches costeros grandes y extremos fue registrado por el mareógrafo de Isla Magueyes - en el suroeste de Puerto Rico - durante 10 días consecutivos, además se registraron cuatro seiches extremos en un periodo de cuatro días, algo nunca antes visto en el registro de eventos que abarca del 1995-2019. Condiciones astronómicas favorables (sizigia, perigeo y declinación lunar cero) generaron corrientes semidiurnas fuertes en el Canal de St. Lucia y Pasaje de St. Vincent, que a su vez generaron una marea interna semidiurna que se propagó hacia el oeste a lo largo de un corredor (14° N a 14.8° N, -62° O a -63.5° O), donde enfrentó un componente zonal U hacia el Este con una magnitud de hasta 0.4 m/s. Esta corriente de trasfondo dentro del corredor fue opuesta a la propagación de la marea interna semidiurna durante una semana completa, facilitando así su evolución no-lineal, y ésta al pasar sobre la Cresta Submarina de Aves generó olas solitarias internas de tamaño mayor y con separación de alrededor de 10 km. Revisando unos 15 eventos de seiches costeros extremos registrados en Isla Magueyes desde el 1995 hasta el 2019, hemos encontrado que en 14 de éstos (93%), el componente zonal U es positivo dentro del corredor de la marea interna semidiurna. Por el contrario, cuando el componente zonal U es negativo, la mayoría de las veces no suelen ocurrir seiches costeros extremos. Por lo anterior, podemos concluir que la dirección-magnitud y duración del componente zonal U de la corriente de trasfondo dentro del corredor es un factor necesario, en adición a los astronómicos, para determinar la amplitud y extensión del campo de olas solitarias internas de amplitud mayor, que se propagan hacia el Mar Caribe Nororiental y que terminarán excitando seiches costeros extremos en Isla Magueyes, en el suroeste de Puerto Rico.

El 1 de noviembre del 2018 imágenes satelitales de Aqua/Terra/MODIS en la banda de clorofila-A detectaron un marcado frente de una masa de agua con relativamente alto contenido de clorofila-A, asociado a la pluma del Río Orinoco, éste chocó en el veril de la Parguera contra las aguas costeras que residen sobre la plataforma insular. Esto causó un acelerado incremento (3-4 cm/día) del nivel del mar en Isla Magueyes, La Parguera. El 2 de noviembre el mareógrafo de la estación de NOOA/NOS/CO-OPS 9759110 registró - dentro de un ciclo mareal diurno - un rápido aumento en el nivel del agua, elevando la pleamar hasta una altura de 0.2 m sobre el datum MHHW. Entre el 6 y 10 de noviembre, cuatro sucesivas pleamares diurnas superaron ligeramente el nivel de 0.20 m sobre el MHHW. Luego entre el 10 y 14 de noviembre, cuatro sucesivas pleamares estuvieron por encima del nivel 0.18 m, una diferencia de sólo 2 cm del anterior. A partir del 14 de noviembre los
niveles empezaron a descender. Por lo anterior, podemos decir que Isla Magueyes estuvo experimentando niveles anormales (>0.17 m sobre MHHW) del nivel del mar entre el 2 y 14 de noviembre de 2018. Este evento ocurrió durante buenas condiciones del tiempo (brisa suave, presión
atmosférica estables, en ausencia de seiches costeros grandes y marea ciclónica). En el mes de noviembre nunca se habían registrado valores tan elevados del nivel del mar en Isla Magueyes bajo buenas condiciones del tiempo, desde que comenzó su registro en diciembre de 1954 hasta el presente. El golpe del frente constituye un fenómeno físico adicional que incrementa el nivel del agua en La Parguera alrededor de 3 cm y que debe ser considerado cuando se examinen los factores que pueden agravar localmente el incremento del nivel del mar.

En el presente trabajo se determinó la prevalencia, abundancia e intensidad promedio de los parásitos encontrados en el intestino de juveniles de Litopenaeus schmitti en las localidades de Curarire (Municipio Cañada de Urdaneta) y Santa Rita (Municipio Santa Rita), Lago de Maracaibo, Estado Zulia, Venezuela. El diagnóstico parasitológico se hizo mediante el examen microscópico en fresco de intestino. La identificación y clasificación se realizó según Levine et al. (1980) y Hutton et al. (1959). Se reporta la gregarina Nematopsis sp (Protozoa: Apicomplexa) en diferentes etapas de desarrollo y una larva de eucestodo (Cestoda: Lecanicephallidae) libres en el lúmen intestinal. Los valores más altos de prevalencia (P= 24,24%), abundancia (A= 4,06 Nematopsis/camarón) e intensidad promedio (IP= 16,75 Nematopsis/camarón) de Nematopsis sp, se observaron en los ejemplares de menor talla (20-35 mm LT), procedentes de la localidad de Curarire. El mayor porcentaje de ejemplares parasitados fueron hembras. Los valores más altos de prevalencia (P= 52,78%), abundancia (A= 63,39 larvas/camarón) e intensidad promedio (IP= 136,50 larvas/camarón) de la larva de eucéstodo (Metazoa: Lecanicephallidae), se registraron en ejemplares de menor talla (55-85 mm LT), procedentes de Santa Rita. En éste caso el mayor porcentaje de ejemplares parasitados fueron machos. No se observaron lesiones ni reacción inflamatoria en el tejido epitelial intestinal que representen un efecto dañino de los parásitos reportados en los ejemplares silvestres de Litopenaeus schmitti.

Starting in 2011, coastal areas of the Caribbean Sea and tropical Atlantic Ocean began to experience extraordinary yearly accumulations of pelagic Sargassum brown alga. Historical reports place large quantities of Sargassum only in the North Atlantic (mostly in the Gulf of Mexico and the Sargasso Sea). Accumulations of Sargassum in the tropical Atlantic have continued. We used a numerical particle-tracking system, wind and current reanalysis data, drifting buoy trajectories, and satellite imagery to determine the origin of the Sargassum that is now found persistently in the tropical Atlantic. Our analyses suggest that during the extreme negative phase of the winter 2009-2010 North Atlantic Oscillation (NAO), unusually strong and southward-shifted westerly winds explain the transport of Sargassum from the Sargasso Sea (∼20-40°N, 80-20°W) into the far eastern North Atlantic. Our hindcast Sargassum distributions agree with surface current simulations with the inclusion of "windage". Windage is the additional, wind-induced drift of material floating at the free surface resulting from direct wind forcing on the sea surface, as well as on floating or partially-submerged objects. In our simulations, windage is included as an added vector (speed and direction) to the model-computed surface ocean currents equivalent to 1% of surface wind velocities. Lagrangian analysis of the regional circulation suggests that (1) part of the Sargassum subsequently drifted to the southwest in the North Equatorial Current (NEC) and entered the central tropical Atlantic, arriving in the Caribbean by the spring of 2011, with (2) another portion continuing southward along the coast of Africa in the Canary Current, eventually joining the seasonally-varying system of tropical Atlantic currents and thereby delivering a large Sargassum population to the tropical Atlantic. Since then, Sargassum patches aggregate from March to September in massive windrows along the Inter-Tropical Convergence Zone (ITCZ) under the action of converging winds. The windrows follow the ITCZ in its seasonal northward migration in the central tropical Atlantic. They are stretched across the central tropical Atlantic as the ITCZ crosses the latitude of the seasonal formation of the North Equatorial Counter Current (NECC). These patches and windrows are exposed to high sunlight and open-ocean upward flux of nutrients due to eddy and wind-driven mixing in the central tropical Atlantic. During the northern spring and summer, as the Sargassum drifts farther north with the ITCZ, large portions of the population are advected into the eastern Caribbean Sea. Some of these patches remain dispersed as the ITCZ migrates southward, and re-aggregate into new windrows as the ITCZ intensifies the following March-April. If wind mixing is strong and the mixed layer is deeper than about 50-60 m in the southern tropical Atlantic at this time, the Sargassum will bloom and form a massive windrow. Otherwise, the bloom will be inhibited. The extreme 2009-2010 NAO wind anomaly could be considered as triggering a biosphere "tipping point" that caused important ocean-scale ecosystem changes in the tropical Atlantic, with significant recurrent social and economic consequences. Understanding whether this new expanded geographic range of massive Sargassum blooms is temporary or whether it will revert to its pre-2009 distribution requires sustained monitoring and research.

The southern Caribbean Sea experiences strong coastal upwelling between December and April due to the seasonal strengthening of the trade winds. A second upwelling was recently detected in the southeastern Caribbean during June-August, when local coastal wind intensities weaken. Using synoptic satellite measurements and in situ data, this midyear upwelling was characterized in terms of surface and subsurface temperature structures, and its mechanisms were explored. The midyear upwelling lasts 6-9 weeks with satellite sea surface temperature (SST) ~1-2 • C warmer than the primary upwelling. Three possible upwelling mechanisms were analyzed: cross-shore Ekman transport (csET) due to alongshore winds, wind curl (Ekman pumping/suction) due to wind spatial gradients, and dynamic uplift caused by variations in the strength/position of the Caribbean Current. These parameters were derived from satellite wind and altimeter observations. The principal and the midyear upwelling were driven primarily by csET (78-86%). However, SST had similar or better correlations with the Ekman pumping/suction integrated up to 100 km offshore (W E 100) than with csET, possibly due to its influence on the isopycnal depth of the source waters for the coastal upwelling. The midyear upwelling was not caused by dynamic uplift but it might have been enhanced by the seasonal intensification of the Caribbean Current during that period.

Hypoxia is the depletion of dissolved oxygen below 2 mg O 2 /L. Relatively few studies on hypoxia and its effects on benthic macrofauna have been done in tropical marine ecosystems. This study describes the temporal response of the water column, sediments and macrofauna to seasonal hypoxia in a semi-enclosed bay (Cienfuegos, Caribbean Sea). The Calisito site was sampled monthly from June 2010 until February 2012, yielding 21 sampling times. At each sampling event water and sediment samples were collected for measuring the abiotic variables (temperature, salinity, dissolved oxygen, nutrients, redox potential discontinuity, silt/clay and organic matter content) and macrofauna (abundance and species richness). Temperature and surface salinity followed a typical temporal pattern during the summer/rainy and the winter/dry periods. Salinity stratification occurred in the rainy period, lasting three months in 2010 and six months in 2011. The bottom water dissolved oxygen indicated hypoxic and anoxic events during the wet periods of 2010 and 2011 associated with salinity stratification, low hydrodynamics and oxidation of the accumulated organic matter. Over the study period, 817 individuals were collected and identified. Polychaetes were the dominant group in terms of abundance (57 % of total) followed by mollusks (41%). Hypoxia (and occasionally anoxia) caused strong deleterious effects on the abundance and species richness of macrofaunal communities in the study site. The most abundant polychaetes were opportunistic species with high tolerance to hypoxic conditions: Prionospio steenstrupi, Polydora sp.and Paraprionospio pinnata. Most of them colonized relatively fast once hypoxia ended. Persistent species such as Caecum pulchellum and Parvanachis obesa were present during hypoxia with fluctuating densities and appar- ently recover to higher abundances when normoxic conditions are re-established. Macoma tenta and Tellina consobrina colonized approximately 1-2 months later than the first polychaete peak during normoxia. Probably, the deleterious effects of hypoxia on the macrofauna were intensified by negative interspecific relationships such as competition by suitable space and predation. The recolonization of macrofauna depended possibly on local transport by currents within the bay because the connection with the Caribbean Sea is relatively limited. In summary, seasonal hypoxia in Cienfuegos Bay influences the water and sediment geochemistry and reduces both the abundance and diversity of macrofauna. Rev. Biol. Trop. 64 (1): 177-188. Epub 2016 March 01.

Sixteen years of sea surface temperature (SST, 1994-2009) were used to characterize the southern Caribbean upwelling system. This system extends from 61-75.51W and 10-12.51N, with 21 upwelling foci clustered in seven groups differentiated by their SST cycles. Two of those groups had the strongest coastal upwelling: the 'eastern area' (63-651W) and the 'western area' (70-731W). The literature reports that the eastern and western upwelling areas hold 78% and 18% of the small pelagic biomass within the upwelling system, respectively. We looked into variations of the upwelling dynamics in those areas using seasonal cycles of satellite SST, chlorophyll-a (Chl) and sea-wind, as well as climatological hydrographic data from the World Ocean Atlas. Comparing their annual averages, the eastern area featured the lowest SST (25.24 1C) and the highest Chl (1.65 mg m −3); it has moderate wind intensity (6.12 m s −1) and shallower 22 1C isotherm (85 m). The western area had stronger winds (8.23 m s −1) but deeper 22 1C isotherm (115 m), slightly higher SST (25.53 1C) and moderate Chl (1.15 mg m −3). The upwelling in the eastern area was more prolonged than in the western area (SST o26 1C during 8.5 and 6.9 months, respectively). According to the 'optimal environmental window' theory, small clupeoid recruitment is a dome-shaped function of the upwelling intensity, turbulence and SST, with an optimum wind speed around 5-6 m s −1. The eastern upwelling area wind speed is close to this optimum value. The western upwelling area shows much higher wind speed that causes high level of turbulence and strong offshore transport that could hinder small pelagics recruitment in that area.

This study reports the first dicephalic shark's embryo of smalleye smooth-hound Mustelus higmani and the eighth case in blue shark Prionace glauca. Each embryo was removed from the womb of a pregnant female, caught in coastal waters of the Caribbean Sea, near to Nueva Esparta state. The dicephalic embryos are exhibited in the Marine Museum of Margarita. RESUMEN Dos casos de dos cabezas en embriones de tiburón, viuda amarilla Mustelus higmani y el tiburón azul Prionace glauca. Este estudio reporta el primer embrión dicefálico de la viuda amarilla Mustelus higmani, y el octavo caso en el tiburón azul Prionace glauca. Cada embrión fue removido del vientre de una hembra preñada, capturada en aguas costeras del mar Caribe en las cercanías del estado Nueva Esparta. Los embriones dicefálicos son exhibidos en el Museo Marino de Margarita.

Hypoxia is the depletion of dissolved oxygen below 2 mg O2/L. Relatively few studies on hypoxia and its effects on benthic macrofauna have been done in tropical marine ecosystems. This study describes the temporal response of the water column, sediments and macrofauna to seasonal hypoxia in a semi-enclosed bay (Cienfuegos, Caribbean Sea). The Calisito site was sampled monthly from June 2010 until February 2012, yielding 21 sampling times. At each sampling event water and sediment samples were collected for measuring the abiotic variables (temperature, salinity, dissolved oxygen, nutrients, redox potential discontinuity, silt/clay and organic matter content) and macrofauna (abundance and species richness). Temperature and surface salinity followed a typical temporal pattern during the summer/rainy and the winter/dry periods. Salinity stratification occurred in the rainy period, lasting three months in 2010 and six months in 2011. The bottom water dissolved oxygen indicated hypoxic an...

Although sponges are important components of benthic ecosystems of the Caribbean Sea, their diversity remained poorly investigated in the Lesser Antilles. By organizing a training course in Martinique, we wanted both to promote taxonomy and to provide a first inventory of the sponge diversity on this island. The course was like a naturalist expedition, with a field laboratory and a classroom nearby. Early-career scientists and environmental managers were trained in sponge taxonomy. We gathered unpublished data and conducted an inventory at 13 coastal sites. We explored only shallow water habitats (0-30 m), such as mangroves, reefs or rocky bottoms and underwater caves. According to this study, the sponge fauna of Martinique is currently represented by a minimum of 191 species, 134 of which we could assign species names. One third of the remaining non-identified sponge species we consider to be new to science. Martinique appears very remarkable because of its littoral marine fauna ha...

En los ecosistemas rocosos costeros, los anfípodos cumplen un papel importante al representar un vínculo entre los productores primarios y organismos de niveles tróficos superiores. No obstante, son pocos los estudios que han abordado la estructura comunitaria y dinámica de este grupo. Considerando estos aspectos, en esta investigación se planteó como objetivo determinar las variaciones espaciales y temporales de la estructura comunitaria de los anfípodos en dos localidades costeras de Venezuela, y su relación con las variables abióticas salinidad, precipitación, temperatura, pH, oxígeno disuelto, amonio, nitritos, nitratos y fosfatos. Se realizaron muestreos mensuales de los organismos para estimar la abundancia y riqueza de la comunidad de anfípodos en las playas Caracolito y Caimán, desde junio de 2014 hasta junio de 2015. Se registró un total de 20 especies, representantes de 10 familias de anfípodos. Las especies más abundantes fueron Hyale pygmaea, Elasmopus pectinicrus y Amphitoe marcuzzii. No se encontraron diferencias estadísticamente significativas en la riqueza de especies entre meses o playas. Se observó una variabilidad temporal de la abundancia total de individuos en ambas localidades, con la mayor densidad en agosto (618 ± 3 ind/100 cm 2) y la menor en diciembre (48 ± 2 ind/100 cm 2). Los patrones de abundancia se relacionan con las variables fisicoquímicas temperatura y salinidad, lo que sugiere que la comunidad de anfípodos puede ser sensible a las fluctuaciones de las condiciones ambientales. Palabras clave: Caribe sur, crustáceos, peracáridos, plataforma rocosa, variabilidad temporal.

Amphipod community dynamics in two rocky shores of Miranda state, Venezuela In rocky shores ecosystems, amphipods play an important role by representing a link between primary producers and organisms at higher trophic levels. However, there are very few studies on the community structure and dynamics of this group. Considering these aspects, the objective of this research was to know the spatial and temporal variations of the community structure of amphipods in two coastal localities of Venezuela and their relationship with the abiotic variables salinity, precipitation, temperature, pH, dissolved oxygen, ammonium, nitrite, nitrate, and phosphate. Monthly samples of the abundance and richness of the amphipod community were carried out on the Caracolito and Caimán beaches between June 2014 and June 2015. A total of 20 species were recorded, representing 10 families of amphipods. The most abundant species were Hyale pygmaea, Elasmopus pectinicrus, and Amphitoe marcuzzii. No significant differences were found in species richness between months or beaches. A temporal variability of the total abundance of individuals was observed in both locations, with the highest density in August (618 ± 3 ind / 100 cm2) and the lowest in December (48 ± 2 ind / 100 cm2). Also, a relationship was found between the abundance patterns and the physicochemical variables temperature and salinity, which suggests that the amphipod community is sensitive to fluctuations in environmental conditions.

We examined the variability of sea surface carbon dioxide fugacity (fCO 2sea ) and its relation to temperature at the Cariaco Basin ocean time-series location (10130 0 N, 64140 0 W) for the period from 1996 through 2008. Periods of warm (positive) and cold (negative) anomalies at the station were related to variability in coastal upwelling intensity. A positive temporal trend in monthlydeseasonalized sea surface temperatures (SST) was observed, leading to an overall increase of 1.13 1C over 13 years. Surface fCO 2sea displayed significant short-term variation (month to month) with a range of 330-445 matm. In addition to a large seasonal range (58 7 17 matm), deseasonalized fCO 2sea data showed an interannual positive trend of 1.77 7 0.43 matm yr À 1 . In the Cariaco Basin, positive and negative anomalies of temperature and fCO 2sea are in phase. An increase/decrease of 1 1C coincides with an increase/decrease of 16-20 matm of fCO 2sea . Deseasonalized fCO 2sea normalized to 26.05 1C, the mean Cariaco SST, shows a lower rate of increase (0.51 7 0.49 matm yr À 1 ). Based on these observations, 72% of the increase in fCO 2sea in Cariaco Basin between 1996 and 2008 can be attributed to an increasing temperature trend of surface waters, making this the primary factor controlling fugacity at this location. During this period, a decrease in upwelling intensity was also observed. The phytoplankton community changed from large diatom-dominated blooms during upwelling in the late 1990's to blooms dominated by smaller cells in the first decade of the 21st century. The average net sea-air CO 2 flux over the study period is 2.0 7 2.6 mol C m À 2 yr À 1 employing the Wanninkhof parameterization, and 2.1 72.5 mol C m À 2 yr À 1 based on Nightingale's model. To further understand the connection between the changes observed in the Cariaco Basin, the relationships between interannual variability in the temperature anomaly with three modes of climate variability (AMO, NAO and ENSO) were examined. The correlations between SSTA and two of these climate modes (AMO and ENSO) only show very weak relationships, although they were significant.

Resumen. La Fosa de Cariaco en la plataforma continental de Venezuela está compuesta por dos sub-cuencas de ~ 1400 m de profundidad, alineadas de este a oeste. En la cuenca oriental se lleva la serie de tiempo CARIACO (1995-) con mediciones mensuales hidrográficas, biogeoquímicas y ecológicas. Sin embargo, se conoce menos de la cuenca occidental. Se realizaron dos cruceros oceanográficos (FOSA 1 y FOSA 2) en septiembre 2008 (época de estabilidad y lluvia) y marzo 2009 (época de afloramiento y sequía), para analizar la variación espacial y estacional de la hidrografía de ambas sub-cuencas. La temperatura superficial del mar fue uniforme y cálida (28-29 °C) en ambas cuencas en septiembre, y disminuyó en marzo, cuando la cuenca oriental fue significativamente (p < 0,05) más fría que la occidental (22-24 °C y 24-26 °C), debido a la surgencia estacional en el sector sureste de la Fosa. La salinidad superficial fue menor en septiembre por la influencia de las aguas superficiales del Caribe y la descarga de ríos locales. En marzo, el nivel del agua Subtropical alcanzó la superficie, elevando los valores de salinidad en toda la región. Los cambios hidrográficos estacionales que experimenta la Fosa influyeron en la concentración de nitrato y clorofila a (Chla) superficial, ambas bajas en septiembre (< 0,1 μM y < 0,3 μg L-1 , respectivamente), y más elevados en marzo, en particular en el área de influencia de la surgencia (> 2 μM y > 1,4 μg L-1). El máximo en profundidad de la Chla también afloró durante la época de surgencia, de 50-60 m en septiembre a 0-40 m en marzo. Se muestra una diferencia significativa entre las cuencas oriental y occidental según la época sea de estabilidad o surgencia. La cuenca occidental presenta una variación estacionalidad menos pronunciada. Palabras clave. Hidrografía. Clorofila. Fosa de Cariaco. Estacionalidad. Mar Caribe, Venezuela. Spatial and seasonal hydrographic and biogeochemical changes in the region of the Cariaco Basin Abstract. The Cariaco Basin is a semi-enclosed basin of tectonic origin composed of two ~ 1400 m deep sub-basins, aligned in an east-west direction. In the eastern sub-basin, the CARIACO Ocean Time-Series project has been taking biogeochemical and ecological measurements on a regular basis since 1995. However, relatively little is known about the western sub-basin. Two oceanographic cruises (FOSA FOSA 1 and 2) in September 2008 (stratified water column; rainy season) and March 2009 (upwelling; dry season), were conducted to analyze the spatial and seasonal variation in hydrography and geochemistry of both sub-basins. During September 2008, sea surface temperature (SST) was relatively uniform throughout the basin (28-29 °C), and decreased in March 2009, becoming significantly colder in the eastern than in the western sub-basin (22-24 and 25-26 °C, respectively; p < 0.05), due to the seasonal upwelling which occurs in the southeastern part of the basin. Surface salinity was lower in September, due to the influence of surface waters from the Caribbean and the discharge of local rivers. In March, Subtropical Underwater (SUW) reached the surface, raising the salinity values throughout the region. The seasonal hydrographic changes that the basin experiences influenced the surface nitrate and chlorophyll concentrations, both low in September (< 0.1 μM and

The Cariaco Basin, located on the continental margin of the southeastern Caribbean Sea, has been a site of extensive oceanographic research since the early 1950s. Here we examined the seasonal and spatial variability in satellite wind, sea surface temperature (SST), surface chlorophyll (CHL), and primary production (PP) within the Cariaco Basin (1994-2009). This variability has implications in modulating the vertical flux of particulate material to the bottom of the basin. While cross-shore Ekman Transport was positive (upwelling inducing) year-round, it showed 20-60% higher values (stronger upwelling) in the eastern sub-basin, compared to the western sub-basin 1.35-2.77 m 2 s −1 and 1.06-1.73 m 2 s −1 , respectively; p < 0.01). This translated into differences in CHL concentration and PP rates between the eastern and western Cariaco sub-basins. Long-term seasonal means of SST, CHL, and PP showed significant inter-basin differences (p < 0.01) between December and July; during that period the eastern basin was cooler (24.86 ± 1.03°C vs. 25.56 ± 0.80°C, p < 0.01), with higher CHL (0.50 mg m −3 vs. 0.35 mg m −3 ; p < 0.01) and PP (1763 ± 994 vs. 782 ± 129 mg C m −2 day −1 , p < 0.01) than the western sub-basin. The eastern Cariaco sub-basin had larger seasonal amplitude and variability in oceanographic characteristics than the western sub-basin, while the western sub-basin had slightly higher and more variable seasonal riverine runoff inputs. These differences have implications for the interpretation of the paleoclimate sediment record stored in different sectors of the Cariaco Basin. ARTICLE HISTORY