MEPS 516:187-194 (2014)  -  DOI: https://doi.org/10.3354/meps10996

ABSTRACT: In the current era of reduced coral populations, the effects of predation are likely to compromise the growing investment in restocking of imperiled coral populations and may be a strong, chronic deterrent of natural population recovery. A 2 yr surveillance study documented highly variable prevalence of predation by the fireworm Hermodice carunculata on both wild (0 to 51%) and restocked (0 to 53%) populations of the Caribbean staghorn coral Acropora cervicornis, but significantly higher prevalence overall in 2012 than 2011. In addition, individual predation scars (branch tips) were tagged to determine the costs of predation both in terms of healing time (i.e. to recover positive rates of branch growth) and in terms of likelihood of progressive disease-like tissue loss on preyed branch tips. The risk of preyed branches showing progressive tissue loss at the subsequent survey was 10 times higher than for non-preyed branches. A survival analysis indicated an estimated mean time to healing for preyed branch tips of 110 ± 6 d (95% confidence). Finally, an experiment conducted in 2013 tested whether removing the dead skeleton from preyed branch tips could accelerate recovery. Indeed, this intervention shortened the mean time to formation of a new apical tip to 46 d (range: 22 to 92 d). Thus, fireworm predation imposes significant costs on both remnant wild and restocked staghorn colonies, but removing dead tips, rather than leaving them to bioerode, is a useful strategy to accelerate recovery from predation.

KEY WORDS: Hermodice carunculata · Acropora cervicornis · Corallivory · Florida Keys · Restoration