The study examined the effect of hydrocarbon pollution on aquatic resources and water quality in Qua Iboe estuary, Nigeria. Specifically, the study was designed to identify the concentration levels of heavy metals arising from petroleum activities on marine resources using fish genera composition, condition factor and tissue analysis. Data for the study was obtained by extracting 1 gram of six different species of fisheries obtained from the estuary and macerated in 10ml distilled water and the aqueous extract used to analyze the heavy metal concentrations. Adult specimen of fish species were collected upstream and down streams from the Qua Iboe estuary using combination of traps and gill nets to determine the fish condition factor. The fish specimens were kept in coolers packed with ice and transported to the laboratory where the wet weight and total length of individual fish was measured with an electric weighing balance and a meter rule, employed in calculating the fish condition factor. Fish tissue analysis for heavy metal was carried out using PerkinElmer flame and graphite furnace atomic spectrometer (PerkinElmer, 4100ZL) which exposed micrograms per gram. The result revealed that the condition factor (k) values ranged between 0.784 to 0.895. These were outside the recommended level. Also, the tissue analysis of the different fish species showed that the concentration of lead (pb), Iron (Fe), Copper (cu), Cadmium (cd), Manganese (Mn), and Zinc (Zn) approached critical levels. This implies that petroleum exploration and exploitation activities pose eminent risk to fisheries development as obvious ecological stressors and perturbation abound in the estuary. Based on these findings, the study strongly recommends the need for a sound and effective environmental monitoring designed programme to be carried out by the oil and gas industry operating within the Qua Iboe river estuary of Ibeno with a view to reducing its negative effect on the estuary. Also there is need for timely clean up of pollutants from oil exploration and exploitation activities in the estuary to be done to cushion this negative effect on the aquatic life forms.
