Southern India is well distributed with wetlands. In these wetlands the water quality parameters play key role in fish’s microhabitat predilection and can be used as index of biological productivity in freshwater ecosystem. The present work was, mainly, intended to create information on physicochemical parameters along with fish diversity indices in the Theroor wetland ecosystem at Kanyakumari districts, for four seasons i.e. one year period from 2014-2015 to have a vivid idea of the ecological status of the selected wetland surrounded by agricultural lands, small scale industries and macrophyte infested water body situated at Kanniyakumari district of Tamilnadu comprising 80 Sqkm of area. Hence, proper scientific management of parameters like temperature, pH, dissolved gases (DO2), hardness, BOD etc., seems to be essential prerequisite for maintaining and monitoring wetlands health. All the analyzed parameters showed significant seasonal fluctuation in the water quality. The studies revealed that the certain physicochemical parameters were satisfactory with few exceptions like hardness and BOD. Similarly in the study area fish diversity analysis showed six order of fishery diversity and density were recorded with that percentage viz., Perciformes (38%)>Cypriniformes (31%) >Siluriformes (13%) >Ophiocephaliformes (8%) >Anguilliformes (7%) >Cyprinodotiformes (3%) and among the 6 order the range of fish density viz., Perciformes (38%) >Cypriniformes (31%) >Siluriformes (13%) >Ophiocephaliformes (8%) >Anguilliformes (7%) >Cyprinodotiformes (3%) were recorded respectively.
