Evaluating the effects of catch-and-release angling on Cape stumpnose Rhabdosargus holubi in a South African estuary

Fisheries managers are increasingly promoting catch-and-release (CR n = 169). Although all fish exhibited at least one reflex impairment, the RAMP score was significantly higher in the 90-s air-exposure treatment (H (2,86) = 9.73, p = 0.007). Also, RAMP scores were significantly lower in the delayed samples (p < 0.01). Although short-term mortality was relatively low (2.3%) for this species, it was highest in the 90-s treatment (7%). These results suggest that physiological stress is higher when R. holubi are exposed to longer periods of air exposure and that the physiological stress of fish subject to a C&R event is best measured after a delay. Keywords : air-exposure, blood glucose, blood lactate, estuarine species, recreational fisheries, reflex impairment, West Kleinemonde Estuary