Abstract
Thirteen morphometric characters of catfish Silurus triostegus were studied from three localities on the Tigris and Shatt al-Arab rivers, Iraq. Monthly samples revealed no significant differences between genders. Positive allometric growths for all morphometric characters studied were observed. This study gives information to fishery biologists about morphometric characters of S. triostegus from the Tigris and Shatt al-Arab rivers to assist in planning of conservation strategies for this fish species.