| Abstrakt: |
The impact of large dams is a prevalent topic in environmental science, but the importance of altered water quality as a driver of eco-biological impacts in a lake ecosystem is often missing from the research in tropical aquatic environments. The sustainability of fishing in Lake Kenyir is becoming increasingly challenging due to overfishing and worrying levels of pollution in numerous riverine locations, which are detrimental to aquatic ecosystems and jeopardize aquatic life, particularly fish. These negative consequences have transformed lake ecosystems into dreadful obstacles that may significantly impair a species’ capacity to carry out essential biological functions like development and reproduction. Based on the above perspectives, this study focused on some characteristics of water quality and reproductive biology (sexual dimorphism, age composition and gonad maturity) of Tinfoil barb Barbonymus schwanenfeldii, among one the popular fish in tropical man-made Lake Kenyir, Terengganu, Malaysia. The morphometric characteristics, meristic counts, age composition, and gonad maturity were investigated to examine the possible sexual size dimorphism, age, and the reproductive status of Tinfoil barb B. schwanenfeldii in Kenyir Lake, Terengganu, Malaysia. 8 morphometric characters showed significant differences within the sexes while meristic and otolith anatomy showed similar characteristics within the sexes. Males and females were of 5 and 1 y above, of age, respectively. Gonadosomatic index was between 3.84 ± 0.66 to 0.92 ± 0.13, and 6.50 ± 0.89 to 7.34 ± 1.11 while the hepatosomatic index ranged from 0.51 ± 0.17 to 0.59 ± 0.08, and 0.39 ± 0.04 to 0.70 ± 0.09 for males and females, respectively. 50% of the males were in the spent stage while 40% of the females were in Stage V, and 30% in Stage III. Thus, selected morphometrics parameters could be useful to differentiate within sexes of Tinfoil barb B. schwanenfeldii. The males B. schwanenfeldii were of older population compared to the female’s population in Kenyir Lake. According to the Malaysia’s National Water Quality Standards (NWQS), the water quality in Kenyir Lake Basin varied temporally and spatially and the most affected parameters were pH, dissolved oxygen, biochemical oxygen demand, chemical oxygen demand, and total suspended solids. The findings of this research may contribute to the further understanding of the eco-biology that aids in effective sustainable fisheries management in this fascinating man-made Lake Kenyir, Terengganu, Malaysia. [ABSTRACT FROM AUTHOR] |
