Mst Ruhina Margia Khanam¹*, Md. Niamul Naser^1,2, Md. Shahadat Ali^1,2

¹Department of Zoology, Faculty of Biological Sciences, University of Dhaka, Dhaka-1000, Bangladesh
²Advanced Fisheries Research Laboratory (AFRL), Department of Zoology, University of Dhaka, Dhaka-1000, Bangladesh

ABSTRACT

The assemble of rotifer communities as well as their relationship to several environmental variables and with other planktonic communities were studied in some coastal ponds of Bakerganj, Barisal during April 2006 to March 2007. In this study five groups of zooplankton were recorded and these were rotifers, nauplii, copepoda, cladocerans and protozoa. The occurrence of different groups of zooplankton was rotifer 41.26 %, nauplii 27.28 %, copepoda 22.34 %, cladocera 8 %, protozoa 1.12 %, respectively. A total of 19 genera and 38 species of rotifer were identified from the seven ponds and a river of the studied area and among them the abundance of major genera of rotifers were brachionus> polyarthra> trichocerca> filinia> keratella >other species, respectively. The highest abundance of rotifer was found in winter and lowest in monsoon. On the other hand, cladocera, copepoda and bauplii were recorded highest in summer and lowest in winter where as protozoa was highest in monsoon and lowest in summer. In this study, protozoa, copepoda, cladocera were considered as biotic factor of the ponds. Some physicochemical parameters of the water such as pH, dissolved oxygen (DO), air and water temperatures of the study areas were recorded during the study period. The water quality was positively or negatively related to the abundance of rotifer. Among the rotifer two types were responded to temperature. One type (Brachionus, Trichocerca, Filinia) preferred high temperature (29-31ºC) and other type (Polyarthra, Keratella) preferred low temperature (20-24ºC). It is also observed that total rotifer density was largest at 24ºC. In conclusion, among the environmental factors the influence of temperature on rotifer species is abundance and river did not appear to be rich in planktonic rotifer community.

Key words: Zooplankton, rotifer, temperature, Barisal, Bangladesh.

*Corresponding author. Tel.: +81 080-6445-6797
E-mail address: mstruhinamargiakhanam@gmail.com (MRM Khanam)                            Full Text (PDF)  Supplementary Materials