Seasonal Feeding Activity, Gut Content Analysis and Morphometric Insights of B. Bagarius from the Indus River

Abstract

This study examines the seasonal feeding activity, gut content composition, and length-weight relationship of Bagarius bagarius from the Indus River, emphasizing seasonal variations in feeding habits and food availability. The feeding activity was categorized into five levels: full stomach, three-quarters full stomach, half full stomach, one-quarter full stomach, and empty stomach, with monthly analyses conducted for each category. The highest proportion of empty stomachs was recorded in January, while peak feeding activity occurred during summer and monsoon seasons, with August exhibiting the highest percentage of full stomachs (45%). Gut content analysis identified diverse food items, including zooplankton, protozoans, crustaceans, insects, molluscs, detritus, plant material, fish larvae, eggs, and scales. Seasonal patterns revealed that B. bagarius predominantly follows a carnivorous diet but opportunistically shifts to omnivory when food is scarce. The morphometric analysis highlighted significant variation in length-weight relationships, showing negative allometric growth (b=1.59). Monthly data revealed differences in feeding intensity between mature and immature individuals, influenced by breeding cycles and seasonal food availability. This research provides crucial insights into the trophic ecology and seasonal adaptations of B. bagarius, shedding light on its ecological role in the Indus River and aiding in the development of conservation strategies for this vital freshwater species