Abstract:
The waters of Rawa Bangkau monotonous swamp, including the South Hulu Sungai Regency,
potentially have several types of swamp fish that are economically valuable, quite high-priced,
and popular with the South Kalimantan people. To date, there has been limited data about the
lake and the resources it holds; the data is essential for proper management, among which are
about the organisms making up the lake. Accordingly, the objectives of this study were (1) to
obtain data and study the conditions of water quality and biology of Rawa Bangkau by
examining the structure of the plankton community, (2) to clarify the stomach contents of
Swamp fish, and (3) to analyze changes in Swamp fish food through a preference index (choice)
based on Ivlev, 1961. The researchers carried out sampling in July-August 2020. The
measurement results showed that: (1) DO (Dissolved Oxygen) measurements showed that the
water conditions were not suitable for aquatic biota and lightly polluted. The nitrate content was
in mesotrophic to oligotrophic conditions. The study site's abundant and diverse plankton
showed low to moderate values, which was the same case with the uniformity and dominance
index; (2) Fish guts indicated that the fish food was relatively the same as what was available in
the waters (plankton); (3) The fish’s eating habits changed due to natural food unavailability.
The preference index showed that fish did not choose their food type – they ate the
