Status of Ichthyofauna under Conservations and Threats in the Historical Pahang River, Pahang, Malaysia

The aim of the present review is based on fish diversity status in the historical Pahang River, Pahang, Malaysia to represent the status of fish composition and its investigation with IUCN status for future monitoring and conservation purposes to the critical fish species. Secondary data were collected from published articles, reviews, field visits, GIS mapping, and books. A total of 259 fish species belonging 19 orders, 50 families, and 146 genera were recorded from the Pahang River waters. Fish from the order Cypriniformes belongings to the family Cyprinidae was documented the most dominant fish group as highest number of species (87 species) followed by the family Siluridae (18 species), Bagridae (16 species), Cobitidae (16 species), Osphronemidae (12 species) and Balitoridae (10 species). Available fishery resources need to be managed carefully as 9 commercial fish species (28.8%) are currently vulnerable and may be extinct in near future. Furthermore, the presence of 14 introduced fish species in the Pahang River waters also requires attention from the respective authorities due to the potential disruption to balance of aquatic systems and ecological circles. Changing land use issues in the Pahang River such as siltation, watershed destruction, rainforest degradation, conversion of wetlands to agricultural and industrial development, land reclamation, mining and logging, construction of barrages and flood mitigation channels. In addition, unstable climatic pattern such as seasonal vast flooding and irregular disturbance by human, illegal and destructive fishing, environmental imbalanced through poisons and pollutants would be significant challenges to the fish diversity management in the historical Pahang River. This study implies to biomonitoring in the Pahang River to ensure sustainable management to aquatic fauna for further studies and development. Thus, effective and necessary mitigation steps should be proposed to protect our valuable bioresources from the Pahang River.