Epipelagic copepods in Bahía Cupica, Colombian Pacific: species composition, distribution and temporal variation. The study of changes in abundance and composition of copepod species, at different temporal and spatial scales, help to understand the ecosystems function and how the oceanographic dynamics affects their variability and other resources abundances. Since very few studies have been developed on this group in Colombian Pacific coastal areas, the purpose of this study was to assess the spatial and temporal changes in the copepods community distribution at Cupica Bay, between December 2012 and February 2013. For this, oblique plankton hauls were performed along six transects perpendicular to the coast, in 22 stations, using a Bongo Net (30 cm diameter, 2.1 m large, with mesh size 250 µm and 500 µm) equipped with a flowmeter, during two contrasting oceanographic periods. The results showed significant changes in oceanographic conditions and superficial circulation patterns. Fifty two (52) copepods species were identified, from which thirty five (35) were new records for the Colombian Pacific. The biggest copepod abundance was recorded in February 2013 (28 604 ind. 100 m -3 ), and small copepods species were the most dominant. During December 2012, species of the order Poecilostomatida were the most abundant (58.2), but during February were the species of the order Calanoida (69.5 %). The community structure and species composition was characterized by five significant groups, three groups during December 2012 and two during February 2013, dividing the bay in different zones. A positive correlation between temperature and copepods assemblages was evident during both periods, but stronger during December 2012. The results suggested that community structure and species composition of resident copepods in North Colombian Pacific neritic zones, are modelled by the intensity of upwelling, superficial local pattern circulation, and continental freshwater discharges in the region. The results are helpful to understand the copepods community structure, and the future studies should attempt to examine other variables (e.g. effect of food available and oxygen concentration dissolved) to improve understanding of copepods structure in the Pacific coast region of Colombia. Rev. Biol. Trop. 65 (3): 1046-1061. Epub 2017 September 01.

Oblique zooplankton tows were carried out in the Gerlache Strait from 17 to 22 January 2015 as part of the first Colombian oceanographic expedition to the Antarctic continent, to document the composition and structure of the epipelagic copepod assemblage, taking into account variations at a small spatial scale. The epipelagic environment of the Gerlache Strait was divided into two oceanographic regions during sampling: a stratified northern region and a homogeneous southern region. The epipelagic copepod assemblage comprised 17 species belonging to four orders and 13 families. Adult copepods as well as developmental stages ranging from copepodite II (C2) to copepodite V (C5) from eight different species were recorded in the study area. The dominant species by number was Oithona similis, followed by O. frigida, Ctenocalanus citer, Drescheriella glacialis, and Calanoides acutus. There were significant differences between the epipelagic copepod assemblages present in the northern and southern regions of the Gerlache Strait (Anosim, p = 0.01), with a dissimilarity percentage of 52%. Moreover, Aetideus armatus is reported for the first time in the western sector of the Antarctic Peninsula. The oceanographic conditions and the geomorphological characteristics of the study area modulated the surface circulation pattern, as well as the structure and composition of the primary producers during the study period, determining the spatial variation of the abundance and composition of the epipelagic copepod assemblage in the Gerlache Strait during the 2015 Austral summer.

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El fitoplancton es uno de los componentes primarios de los ambientes acuáticos marinos. En los arrecifes de coral, tiene un papel fundamental porque provee alimento a los corales y, secundariamente, da alimento al zooplancton, por lo que crea interacciones tróficas importantes en este ecosistema. El deterioro de los arrecifes a nivel global ha ocasionado, entre muchos otros factores, un aumento en la abundancia de especies de fitoplancton debido al incremento de nutrientes y sedimentos que no favorecen a la salud de estos ecosistemas. En el Parque Nacional Natural Corales del Rosario y de San Bernardo, en particular, estos efectos se perciben durante la época de precipitaciones, principalmente por descargas continentales. Por lo tanto, este estudio intenta contribuir con información detallada de la comunidad fitoplanctónica que se presenta en el área protegida y la abundancia relativa durante dicho periodo. Para esto se analizaron 16 muestras recolectadas en la temporada de mayor precipitación entre 2016 y 2019 en cuatro estaciones dentro del área del parque, mediante arrastres horizontales con una red de 63 µm. Se identificaron 228 morfoespecies de fitoplancton que corresponden a especies de ambientes de aguas someras y costeras. Las diatomeas fueron el grupo de mayor representatividad durante 2016, 2017 y 2019, con la presencia de especies como Skeletonema costatum, Chaetoceros affinis y Bacteriastrum furcatum. Durante 2018 los dinoflagelados aumentaron su representatividad por encima de las diatomeas, con la presencia de algunas especies con potencial nocivo como Pyrodinium bahamense y Alexandrium monilatum, las cuales registraron las mayores abundancias relativas en ese año.