In this study bio-indicator bacteria and environmental variable parameters were investigated in the coastal areas of the Gulluk Bay, Aegean Sea, Turkey. The seawater samples which were taken from surface (0-30 cm) were tested regarding total and fecal coliform, streptococci and nutrients from May to February in 2012-2013. The primary hydrographic parameters were recorded using multiparameter (YSI 556) in situ at the sampling stations. The highest fecal pollution stress and indicator bacteria values were observed in the period between June and August. The finding showed that bacterial pollution sources of the study area, especially in the summer season, under the control of increasing anthropogenic activities. The finding showed that terrestrial pollution sources carry a potential risk for public and ecosystem health and the sustainable use of living sources. Precautions should be formulated and put into action immediately in order to protect the region from bacteriological risks. (C) 2015 Elsevier Ltd. All rights reserved.