Disease intervention using amoxicillin paste is effective at stopping stony coral tissue loss disease (SCTLD) lesion progression; however, it does not provide protection against reinfection. Prolonging colony survival may require regular visits to treat new lesions should they appear. Intervention activities in southeast Florida were allocated between regular treatment and monitoring of selected priority colonies and broadscale disease interventions. The latter involved strike team divers, who worked in small groups covering large areas of reef treating all SCTLD lesions observed, tagging the colonies, and recording their locations via a floating GPS. Broadscale disease intervention efforts aimed to maximize the area covered and treat as many disease lesions as possible without the intent of returning to monitor treatment success. Between 2018 and 2024, over 1,800 colonies of 17 different species were treated at over 280 sites. We evaluated this strategy’s effectiveness in preventing colony mortality by revisiting 178 Montastraea cavernosa colonies treated once after 12 months or more prior and recording their condition. 94% of all M. cavernosa colonies were still alive at the time of revisit. Categorizing colonies into elapsed timeframes since treatment yielded high proportions of survival: 100% of colonies treated 13–21 months prior, 97% treated 24–34 months prior, and 87% treated 35–41 months prior. The average percent decrease in live tissue coverage was 18%, 20%, and 30% after 13–21, 24–34, and 35–41 months, respectively. Compared to reported natural SCTLD senescence of about 30%, one-time broadscale interventions provide prolonged colony survival, reducing the burden of post hoc restoration.
Zummo et al. (Mon,) studied this question.