Post-fragmentation recovery in the soft coral Sinularia flexibilis is enhanced by suspension culture

Fragmentation is widely used for the propagation of soft corals, yet the physiological processes governing early post-fragmentation recovery remain poorly quantified. Recovery-related processes such as wound healing and energy allocation are often conflated with growth, potentially obscuring treatment effects. Here, post-fragmentation recovery in the soft coral Sinularia flexibilis (Quoy & Gaimard, 1833) was examined under controlled aquarium conditions, comparing fragments cultured in suspension or placed on the tank bottom, with and without supplemental feeding. Wound healing was assessed using an ordinal ranking system, growth was quantified through repeated morphometric measurements of fragment linear extension and volume, and energetic condition was evaluated via tissue calorimetry. Fragments maintained in suspension progressed through healing stages significantly faster than bottom-cultured fragments, achieving complete tissue closure and earlier polyp regeneration. In contrast, short-term growth rates in linear extension and volume did not differ consistently between culture methods during the recovery period, and survival was 100% across all treatments. Feeding enhanced growth under bottom culture but had limited effects under suspension culture. Notably, tissue energy content was significantly higher in suspended fragments than in bottom-cultured fragments, irrespective of feeding regime. These results demonstrate that culture method strongly influences early post-fragmentation recovery and energetic condition without necessarily affecting short-term somatic growth. The findings support the view that soft corals reallocate energetic resources toward wound repair following fragmentation and highlight suspension culture as an effective strategy to enhance recovery efficiency during early post-fragmentation phases. Distinguishing recovery dynamics from growth is therefore critical for interpreting experimental outcomes and for optimizing soft coral husbandry and propagation practices.