COMPARISON OF CULTURE METHODS FOR THREATENED CARIBBEAN STAGHORN CORAL Acropora cervicornis GROWN IN AN OCEAN-BASED NURSERY FOR RESTORATION

Kelli O'Donnell, Katie Lohr, Erich Bartels, and Josh Patterson*
 
 University of Florida - School of Forest Resources and Conservation
 The Florida Aquarium - Center for Conservation
 Apollo Beach, FL 33572
 joshpatterson@ufl.edu

Staghorn coral Acropora cervicornis has been federally listed as Threatened since 2006, following population declines beginning in the late 1970s. This once ubiquitous framework builder on Caribbean fore reefs has been especially impacted in the Florida Keys, where populations have been reduced by up to 97% in many areas. Of the host of management actions designed to change this trajectory, aquaculture is increasingly used to grow staghorn coral in ocean-based nurseries. The biology of this coral makes it an ideal candidate for culture, and as of 2016 over 100,000 nursery colonies have been outplanted onto reefs in Florida.

A variety of culture methods are employed for staghorn coral. These can be broadly categorized into benthic-attached or water column-suspended, dependent upon how and where the colony is held in place. We compared specific benthic-attached (block) and water column-suspended (tree) systems in a study conducted in a Mote Tropical Marine Laboratory nursery. Total linear extension of each colony was measured monthly for 11 months, and observations of colony health and breakage were also made. Only three colonies survived through November 2015, following an extended period of elevated temperature and subsequent bleaching event. Prior to this date, colonies grown on trees were significantly larger and experienced significantly less breakage than those on grown blocks. Genotype also had a significant effect on colony growth.