Ecological Study of Rotifers from Chandrabhaga River, Kalmeshwar, Dist. Nagpur

Rotifers represent an important component of freshwater zooplankton and serve as a valuable natural food source for fish larvae because of their suitable size range and high nutritional value. The present investigation was conducted to evaluate the diversity and seasonal abundance of rotifers in the Chandrabhaga River at Kalmeshwar, Nagpur District. Water samples were collected over a one-year period from June 2017 to May 2018, and various physicochemical characteristics, including temperature, dissolved oxygen, biological oxygen demand, pH, alkalinity, hardness, and total dissolved solids, were examined in relation to rotifer abundance. A total of eleven rotifer species were identified during the study period. Species belonging to the genus Brachionus constituted the dominant component of the rotifer community. The highest rotifer density was observed during winter, whereas the lowest abundance occurred during the monsoon season. Seasonal variation indicated a positive association between water temperature and rotifer abundance, while increased water flow appeared to reduce population density. The study highlights the ecological importance of rotifers and their usefulness as indicators of freshwater ecosystem conditions.