Copépodos epipelágicos en Bahía Cupica, Pacífico colombiano: composición de especies, distribución y variación temporal

Abstract

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.

Effects of seasonal upwelling on hydrography and mesozooplankton communities in a Pacific tropical cove off Colombia

“…Our results are also consistent with the biomass increase in phytoplankton (~ 9-fold) and zooplankton (~ 2-fold) documented by Smayda (1966) in Bahía de Panamá during the dry season. Likewise, our results agree with the seasonal increase in total mesozooplankton biomass and abundance, as well as the increase of specific groups such as copepods, medusae, and hyperiids that has been documented in coastal waters of Bahía Culebra (Bednarski & Morales-Ramírez, 2004; Rodríguez-Sáenz & Morales-Ramírez, 2012), Bahía de Panamá (Miglietta et al, 2008), Bahía Cupica (Jerez-Guerrero et al, 2017), and Isla Gorgona (Valencia & Giraldo, 2012;Giraldo, Valencia, Acevedo, & Rivera, 2014). In February 2013, although upwelling was evident at Ensenada de Utría in the changes in the environmental conditions of the subsurface waters, these changes were not reflected in an increase of the biomass and abundance of the mesozooplankton.…”

“…During the rainy season, the high cloud cover, high precipitation levels, and the discharge of numerous small creeks into the cove were the main factors modulating the temperatures and salinities at the surface, reflected in salinities lower than 25 and significantly warmer waters in October 2013. The low salinities in combination with the warmer temperatures during the rainy season were also reflected in a less stratified water column compared to the dry season, similar to what has been documented in the Northern Pacific coast of Colombia (Jerez-Guerrero et al, 2017) and in the Gulf of Panama (Smayda, 1966;Forsbergh, 1969;D'Croz, Kwiecinski, Maté, Gómez, & Del Rosario, 2003). During the dry season, the decrease in cloud cover, precipitation, and runoff corresponded with an increase in surface salinities within the cove.…”

“…In Ensenada de Utría, the signal of upwelled waters during the dry season was evident in the subsurface waters in the middle and outer zones of the cove, where temperature and dissolved oxygen concentrations decreased, and salinity increased. Therefore, subsurface waters in the cove followed the expected seasonal pattern that has been documented in Bahía Culebra in the Gulf of Papagayo, Costa Rica (Alfaro et al, 2012), in coastal waters of the Gulf of Panama (Smayda, 1966;Forsbergh, 1969;D'Croz et al, 1991;D'Croz & Robertson, 1997;D'Croz et al, 2003), and in Bahía Cupica (Jerez-Guerrero et al, 2017) and Isla Gorgona in Colombia (Giraldo, Rodríguez-Rubio, & Zapata, 2008;Valencia & Giraldo, 2012). However, whereas in Bahía Culebra (Rixen et al, 2012) and in Bahía de Panamá (Smayda, 1966;D'Croz & Robertson, 1997) the signal of upwelled waters can be detected at the surface, in Ensenada de Utría surface waters remained warm throughout the study period.…”

“…At Ensenada de Utría, it is possible that the increase in food supply during the dry season (i.e., mesozooplankton biomass) was accompanied by a shift in the size structure of the mesozooplankton towards a higher proportion of larger organisms, as has been documented for the copepod assemblages in Bahía Cupica, located further north in the Pacific coast of Colombia (Jerez-Guerrero et al, 2017). The concentration and size of the plankton, as well as the timing and overlap with the food, are all important factors modulating the development and survival of fish larvae (Cushing, 1990;Beaugrand, Brander, Lindley, Souissi, & Reid, 2003;Kristiansen, Drinkwater, Lough, & Sundby, 2011).…”

Composición y abundancia taxonómica del zooplancton desde el Pacífico Sur hasta la Península Antártica 2016-2017

“…

Con el propósito de contribuir al conocimiento del zooplancton asociado a las masas de agua presentes a lo largo de un gradiente latitudinal desde Perú hasta la Península Antártica, se obtuvieron 14 muestras con una red cónica de ojo de malla de 250 µm y 60 cm de diámetro de boca, desde 0 a 200 m de profundidad, en el marco de la III Expedición Científica de Colombia a la Antártica "Almirante Padilla" (Verano Austral 2016-2017. Los resultados permitieron determinar un total de 75 familia/morfotipos (f/m), pertenecientes a 32 órdenes.

…”