Rearing duration influences survival rate in the Post‐Larval Capture, Culture and Release of a coral reef fish

Abstract Introduction Juvenile coral reef fish face an initial predation‐induced mortality bottleneck with mortality exceeding 60% within 48 hours of settlement. This intense predation, exacerbated by anthropogenic stressors, limits recruitment and contributes to global declines of reef fish populations. Post‐Larval Capture, Culture, and Release (PCCR), where fish larvae are captured before settlement, reared in captivity, and released at a later developmental stage, has emerged as a promising restoration strategy. However, the rearing durations that best balance survival and scalability remain unclear. Objective This study aimed to evaluate how short‐term captive rearing duration, a key variable previously inconsistent across studies, influences growth, post‐release behavior, and survival of the Ambon damselfish ( Pomacentrus amboinensis ) as a model coral reef fish. Methods Settlement‐stage fish were captured with light traps, reared for 2, 4, or 6 days, and individually released onto experimental patch reefs. Growth, post‐release behavior, and survival were quantified using a framework designed to isolate the effects of rearing duration and examine its influence on PCCR outcomes. Results Captivity duration significantly influenced survival probability, with 75% of fish reared for 6 days surviving compared to 58% and 61% for 2 and 4 days, respectively. Post‐release feeding rate and vertical positioning were positive predictors of survival, whereas body size had no effect. Early growth did not differ between captive‐reared fish and wild conspecifics. Conclusion By demonstrating the effectiveness of short culture duration, this study provides actionable guidance for integrating PCCR into restoration initiatives alongside complementary conservation measures.