Impact of Ice-Angling and Handling on Swimming Performance in Bluegill and Largemouth Bass

Many recreational anglers practice catch-and-release; however, research indicates that capture and handling has the potential to adversely affect fish. Numerous catch-and-release studies have been conducted during warmer months, but little work has been done during the winter when ice-anglers in temperate regions target fish. We conducted an ice angling simulation that quantified the impacts of air temperature and air exposure duration on swimming performance and gill physiology of Bluegill Lepomis macrochirus and Largemouth Bass Micropterus salmoides. In all experiments, fish were first subjected to a simulated angling bout in water at 5 degrees C, followed by 30 s or 5 min of air exposure at above freezing (3-8 degrees C) or subfreezing (-7 degrees C) temperatures. The fish were then assessed for critical swimming speed (Bluegill), oxygen consumption (Bluegill), burst swimming (Largemouth Bass), or gill damage (Largemouth Bass). Results showed that Bluegill subjected to 5 min of air exposure at -7 degrees C suffered impaired swimming, with a 47% loss in critical swimming speed (U-crit) compared with the controls. Treatment had no impact on burst swimming or gill damage in Largemouth Bass. The results demonstrate the possible impacts of air exposure on fish, and we recommend that ice-anglers make an effort to minimize air exposure duration, especially when air temperatures are low.