Comparing Efficacy of Epoxy Versus Cement for Outplanting Caribbean Staghorn Coral, Acropora cervicornis

Abstract

Acropora cervicornis population declines since the 1970s initiated its listing as threatened under the US Endangered Species Act and critically endangered under the IUCN Red List. In response, restoration by outplanting nursery-reared A. cervicornis fragments to degraded reefs was developed. Here we compare outplanting A. cervicornis fragments using marine epoxy to a 10:1 cement/silica mix in clusters of six fragments across two sites off southeast Florida, USA. The epoxied outplants were established in December 2019 (n=810 fragments) and the cemented outplants were established in December 2020 (n=516 fragments). Outplant survival, attachment, and predation and disease prevalence was tracked for one year. Additionally, the effort associated with outplanting using each method was compared. After one year, the survival rate for the epoxied and cement fragments was 66% and 95%, respectively. Missing fragment prevalence for epoxied and cemented fragments was 24% an