Diffused inputs into the marine environment are now recognized as highly significant for some heavy metals. An attempt has been made in the present study to understand the seasonal variation of nickel resistant bacteria diversity in the coastal zone of Chennai, India. A reduction in nickel resistant population was observed with increase in depth when compared to samples collected near the shore. The trend of Nickel resistant bacterial population was found to be Fishing Harbor Traverses > Chennai Harbor Traverses > Cooum River Traverses = Ennore Traverses > Adyar River Traverses. The results of the present study clearly showed the increase in the development of metal resistance among the bacterial population during the study period. The nickel resistant bacterial population in the surface sediment samples studied off Chennai in Bay of Bengal during the three consecutive years varied between 3.3 and 5.3 log10 CFU/g with an average of 4.4 log10 CFU/g of sediment.

Nickel resistant bacteria, microbial population dynamic, anthropogenic impact, bio indicators.