Recent decade of growth and calcification of Orbicella faveolata in the Florida Keys: an inshore-offshore comparison

Abstract

Coral reefs along the Florida Keys portion of the Florida Reef Tract (FRT) have undergone a dramatic decline since the 1980s. Since the 1997−1998 El Nino event, coral cover on offshore reefs of the FRT has been ≤5% and continues to decline. Mortality of the frameworkconstructing coral in the Orbicella (formerly Montastraea) annularis species complex has driven this recent loss in overall coral cover. One exception to this decline occurred on the inshore patch reefs of the Florida Keys, where coral cover has remained relatively high. We examined the growth and calcification of Orbicella faveolata, an ecologically important subspecies of the O. annularis complex, at both an inshore and an offshore reef site representing this dichotomy of present-day coral cover. The period examined (2004 to 2013) encompasses the Caribbean-wide 2005 mass coral bleaching, the 2009−2010 catastrophic cold-water bleaching, and a warm-water bleaching event in 2011. Extension and calcification rates were higher inshore every year from 2004 to 2013 except when there were thermal stress events that solely impacted inshore reefs (as in 2009−2010 and 2011). Inshore growth rates recovered quickly from cold and warm-water stress. These higher calcification rates and their quick recovery after thermal stress are likely important factors in the persistence of high coral cover inshore.