Presence and Composition of Planktons’ Organisms in Ships Ballast Water Discharged in Al-Mukalla Harbor, Gulf of Aden

This was the first study in Yemen, and Gulf of Aden aims to investigate the marine organisms in ballast water and sediments, and gives baseline information defines the zooplankton, phytoplankton and invertebrates, associated fuel tankers. Samples from Ballast water were taken from three ships that arrived at Mukalla Port, the Hadhramout coast from ports of Hamriyah port, U.A.E; ports of Taheri, Iran; and Bosaso Somalia (MT: Gulf Petroleum III, MT: Prime Royal, and M T: Breu) respectively. The marine organisms in samples were presented by three taxonomic groups, phytoplankton, zooplankton and benthos. Fifty-eight taxa were identified within this study; which consisted of 17 phytoplankton, 18 zooplanktons and 23 Benthos. The highest density of phytoplankton was 21 Ind/L, with the occurrence of 17 species found in ballast water, while 22 Ind/50cc of 2 species in sediment samples of the tanker Beru, and fewer densities were in Gulf Petroleum and Prim Royal. The most common phytoplankton observed were Coscinodiscus granii, Coscinodiscus jonesianus and Thalassiosira eccentric. The low Zooplankton density was 13 Ind/L with an occurrence of 18 species found in Prim Royal tanker. Copepods were the most dominant zooplankton among the three tankers. Paracalanus parvus had the highest value of dominance followed by Calanopia parathompsoni, Acrocalanus gracilis and Paracalanus denudatus had the lowest occurrence over three tankers. Seven taxa of Dinoflagellates were identified; two of them Ceratium fusus and polykrikos sp. are known to be harmful species.