This research study aimed to analyze the physico-chemical characteristics of Bitan- ag creek and to assess zooplankton diversity. Specifically, it determined (1) the physico-chemical condition and nutrient load of the creek and compared to DENR Administrative Order (DAO) standard, (2) assessed how the physico-chemical parameters affect the distribution and abundance of zooplankton, (3) identify zooplankton species that are found in each sampling sites, (4) measure significant difference on the abundance and diversity of zooplankton between sites. The study made used of the descriptive-comparative design to determine quantitatively water quality parameters such as conductivity, water temperature, TDS, turbidity, salinity, water current, COD, DO, pH, nitrates and phosphorus. The results clearly revealed that some physico-chemical and nutrient load parameters exceeded the standard of class “C” water body, this includes: conductivity, TDS, turbidity, DO and phosphate content. A total of five (5) species of zooplankton belonging to three (3) families namely: Appendicularia, Daphniidae and Ameiridae were present. Family ameiridae had the highest total number of three individuals which are found in first and third sites, whereas, the appendicularia and daphniidae settled only in the third sampling sites. Further, the study also showed significant difference on the abundance and diversity of zooplankton between sites. Thus, the distribution and abundance of zooplankton in Bitan –ag creek were greatly influenced by the condition of its physico-chemical and nutrient chemistry. The research suggested that there should be rehabilitation of Bitan –ag creek to avoid further degradation of its water quality.
