ABSTRACT
The Silver Catfish (Chrysichthys nigrodigitatus) plays a crucial role in the Calabar River ecosystem, influencing local economies and aquatic biodiversity. This study assesses the trophic cascades and food scarcity effects on the Silver Catfish, focusing on its morphometric parameters and seasonal variations during the dry and wet seasons in the Calabar River. Key parameters, including body weight, total length, and fin lengths, were analyzed, with statistical tests applied to determine seasonal differences. Significant seasonal variations were found in dorsal fin length, caudal fin length, and head length. Specifically, dorsal fin length increased from 6.94 cm in the dry season to 9.69 cm in the wet season (p = 0.00073), caudal fin length from 9.31 cm to 12.55 cm (p = 0.0049), and head length decreased from 13.75 cm to 11.88 cm (p = 0.023). These variations likely reflect changes in feeding behavior due to trophic cascades, where predator-prey interactions and food availability are altered by seasonal factors, resulting in food scarcity during the dry season. This highlights the need for effective seasonal management and conservation strategies to mitigate food scarcity impacts, protect the species, and maintain the health of the Calabar River ecosystem.
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