Physiological response to angling of Africa’s premier freshwater angling species, the tigerfish Hydrocynus vittatus

摘要: Angling fraternities widely promote catch-and-release (C&R) as a fisheries management tool. This study aimed to determine the physiological response of Africa’s premier freshwater angling species, tigerfish Hydrocynus vittatus , C&R in Okavango Delta, Botswana. Standard techniques were used collect fish, whereafter fish anaesthetised clove oil, blood drawn from caudal vein and general biometric data noted, then revived released. Blood plasma was analysed for glucose, cortisol lactate concentrations assess effects duration, size condition. Larger angled longer duration. Plasma glucose decreased with greater concentrations, an indication aerobic anaerobic work done during capture. Few individuals showed increased concentrations. In extended-capture (angled >1 min), significantly above values control fish. A linear regression analysis that well-fed had less stress compared individuals. Furthermore, discriminant function indicated suite biomarkers successful indicating different responses according handling times along nutritional status likely influential factors range especially levels this study. These suggest causes tigerfish, but could nonetheless be valuable tool, ensuring sustainability populations. Keywords: cortisol, analysis, lactate, biomarkers, univariate statistics