Fish Biodiversity and Water Quality of Tropical Forest Streams Adjacent to the Western Boundary of Kinabalu Park, Sabah

Modification and degradation of habitats outside the boundaries of a national park may result in the park's integrity being compromised. Thus, the present study aims to document variation in freshwater fish and water quality of tropical forest streams adjacent to the western boundary of Kinabalu Park, Sabah. Concurrently, fish samples and environmental parameters were collected at six stations covering a total streamline length of 10 km. The three most abundant species were Tor tambra (34.4%), Barbodes sealei (19.5%), and Lobocheilos ovalis (12.4%). Tor tambra exhibited a negative allometric growth pattern (coefficient < 3) and was in poor to fair condition (0.8 < Fulton’s condition factor < 1.2). The highest fish abundance was found in downstream stations with species addition. Metrics of diversity, such as Shannon's diversity index and the Margalef index of species richness, decreased as elevation increased from 100 to 600 metres above sea level. The water quality of the forest streams is good, classified as Class I and/or Class II by Malaysia's National Water Quality Standards, except for ammoniacal nitrogen at station 6, which was classified as Class III. Higher turbidity, orthophosphate, and ammoniacal-nitrogen values were found near the Podos village. In conclusion, the altitudinal gradient of fish biodiversity was observed in the forest streams near Kinabalu Park. Regular water quality monitoring of the downstream river is necessary, as indicated by the potential domestic impacts on the river

Survey of freshwater fish in Kadamaian area, western Sabah

The freshwater fish fauna was surveyed in forest streams located in the Kadamaian area, Sabah during the Borneo Geographic Expedition 2019. Fish samples were obtained from six stations by electrofishing from an upstream to downstream direction. A total of four families, 12 genera, and 14 species of fish were recorded from the present study. The most dominant family was Cyprinidae (10 species; 71.43%), followed by Gastromyzontidae (2 species; 14.29%), Nemacheilidae (1 species; 7.14%), and Mastacembelidae (1 species; 7.14%). The number of species was low in upstream stations at higher altitude but substantially higher in downstream stations with lower altitude. Economically valuable fish, Tor tambra was found at all stations. Gastromyzon monticola which is endemic to Sabah was also recorded at most stations