Length-weight Relationship and Condition Factor of Four Catfish Species (Actinopterygii: Siluriformes) from the Stanley Reservoir, Tamil Nadu, Southeast India

Background: The length-weight relationship is estimated for four catfish species in order Siluriformes. Methods: Fish samples were collected from the three sampling stations at Stanley Reservoir, Tamil Nadu, Southeast India, between December 2021 to November 2022. Fulton’s condition factor (KF) (Fulton, 1904) , calculated using the formula KF = (W/L^3) x 100 and Relative condition factor (KR) using the equation KR = W/(a x Lb3) was employed to evaluate the health of the subjects and variations in form or condition with length respectively. Result: The estimated b values range from 2.50 to 3.77. This study also provides the length-weight relationship for the newly described species, Pangasius icaria, which possesses delicacy in commercial markets. Both Fulton’s condition factor (KF) and relative condition factor (KR) further highlight the health and ecological status of these species. These findings provide critical baseline data for the conservation and management of catfish species in this reservoir, highlighting the impact of anthropogenic pressures on their populations.