Ron Hill; Hannah Nylander-Asplin; Jennifer Doerr

Population Dynamics and Genotypic Richness of the Threatened Acropora spp. and their Hybrid in the U.S. Virgin Islands Annual Report 2019

2019

NOAA Southeast Fisheries Science Center

"In September 2019, we collected 63 colonies from reefs surrounding St. Thomas and St. John as a continuation of a multifaceted approach to understand the ecology and population dynamics of the threatened Acropora taxa. Starting in 2009, three long-term transect sites were established at Thatch Cay, Lovango and NoName Bay around eastern St. Thomas and St. John. These sites have been used to quantify changes in A. cervicornis cover and determine the relative health of the colonies on the transect. Along with quantifying abundances of A. cervicornis and A. prolifera at these sites, colonies sampled in 2019 were genotyped using microsatellites to determine genotypic richness and thus the main method of propagation for each taxa and site. In addition to quantifying shifts in coral cover, the colonies collected for genotypic analysis were also fragmented and hung in the University of the Virgin Islands (UVI) coral nursery near Flat Cay on the south side of St. Thomas. Here, we are investigating the comparative growth rates and general health of A. cervicornis and A. prolifera in a nursery setting. By using parental and hybrid colonies from different sites, colonies that are naturally more resilient to thermal stress, disease and other disturbance events can be identified and further studied with the main goal of propagating and out-planting these colonies back onto the reef. Once colonies are out-planted, we can observe the health and growth rates of A. cervicornis and A. prolifera in situ to identify differences in health, growth and survival."

population dynamics, genotypic analysis, genotypic richness, coral restoration, Acropora cervicornis, Acropora palmata, Acropora prolifera, USVI

NMFS

SEFSC

FY2019 CRCP Project ID 31243; Project Title: Guiding Restoration of Virgin Island reefs: Are hybrids more resilient?; Principal Investigator: Ron Hill