We conducted tests to quantify delayed mortality of white crappie (Pomoxis annularis) after catch and release by anglers. White crappie were subjected to I) catch and release in shallow water using traditional hook-and-line methods and 2) rapid depressurization to simulate catch in deep water. Mortality 6-11 days after catch and release from shallow water averaged 3%. No significant differences (P > 0.05) were detected between mortality rates of white crappie 15-25 cm and >25 cm total length, nor between fish caught using live and artificial baits. No mortalities occurred 96 hours after white crappie were depressurized from depths ≤10m, but 29% and 67% of the fish died when depressurized from 13 and 16 m, respectively. Regulations involving catch and immediate release of white crappie can reduce fishing mortality, but may be less effective when and where fish are frequently caught from deep water.
