Community Structure and Abundance of Epipelagic Copepods in a Shallow Protected Bay, Gulf of Thailand

Abstract

The community structure and abundance of epipelagic copepods in a shallow protected bay (Manao Bay, Gulf of Thailand) were studied twice a week from September 2006 to August 2007.  Copepod samples were collected by vertical hauling using a conical 0.6 m diameter plankton net with 200 µm mesh size. Twenty-eight species from 19 genera were recorded. The mean abundance was 4,064 ± 263 individuals. m^-3. The dominant species were Acartia erythraea Giesbrecht (7.16%), Corycaeus asiaticus Dahl (4.72%), Pseudodiaptomus aurivilli Cleve (4.17%) and Euterpina acutifrons (Dana) (3.85%). Copepodid stages were more dominant than the other stages, consisting of 64.19% of the total copepod abundance. The carnivores were the most abundant at 17.55%, followed by the omnivores (13%) and the herbivores (3.33%). Total abundance of the copepods showed a temporal variation. The Shannon - Wiener diversity index ranged from 1.66 to 2.49. But the detected similarities to temporal variability showed no difference in species composition. The epipelagic copepod community in this bay was low in diversity but high in abundance throughout the year.