Effects of Catch-and-Release Angling on the Physiology and Behavior of Juvenile Lemon Shark in the Bahamas

Targeting sharks with hook and line angling is becoming more prevalent within the recreational angling community. Although catch-and-release is often advocated as a conservation measure for protecting these apex predators, little research has been conducted to quantify the effects of catch-and-release angling on sharks. Juvenile lemon sharks (Negaprion bevirostris) are vulnerable targets of anglers that frequent tropical flats. As such, we measured the physical impacts, physiological response, and post-release behavior and mortality of juvenile lemon sharks caught near Eleuthera, The Bahamas. A total of 32 sharks ranging from 530-875 mm (TL) were caught and released using spinning rods, dead bait, and circle hooks (5/0). Following release, each shark was tracked for 20 min using a visual float. Hooking in the tongue was most prominent (59%), following by corner jaw (31%), face/eye (6%), and gut (3%). Two sharks (6.25%) hooked in the tongue died prior to release. Two sharks (6.25%) died post-release, both when water temperature was at or near 35°C. Of the physiological parameters measured, only blood lactate (0.3-6.31 mmol/L) and potassium (6.02-9.81 mmol/L) correlated positively with fight time. Results indicate that hooking injuries and environmental conditions contribute to the overall stress of catch-and-release angling for juvenile lemon sharks.