Ecology, Environment and Conservation Paper

A STUDY ON EFFECTS OF SHIP BALLAST WATER DISCHARGES ON THE ZOOPLANKTONS IN CALABAR COASTAL WATERS

S.U. Jatau, M.C. Emere, M.S. Abdulsalam, Y. Umar and N.A. Etangetuk

Abstract

The distribution, abundance and seasonal variation of Zooplanktons collected from coastal stations and ship ballast tanks were investigated. In the Coastal water nine (9) major taxa of Zooplanktons were recorded namely Arthropoda (25.9%), Rotifera (23.3%), Copepoda (16.4%), Annelida (9.9%), Ciliaphora (9.5%), Protista (7.1%), Decapoda (4.6%), Cladocera (1.7%) and Chaetognat ha (1.6%) were observed. In Ballast water eleven (11) major taxa were recorded namely Arthropoda (26.4%), Cladocera (22.3%), Rotifera (17.4%), Copepoda (13.4%), Ciliaphora (9.4%), Chaetognatha (6.1%), Decapoda (1.8%), Mollusca (1.3%), Ctenophora (0.8%), Gastropoda (0.8%), and Cnidaria (0.04%). The seasonal variation of Zooplanktons in the Calabar coastal water showed that zooplanktons abundance was highest in the months of August, October and December. In Ship ballast water zooplanktons recorded the highest abundance in September, November, January, February and March. Alien species were found in the Calabar coastal water which were probably introduced by ship ballast water discharged.