Coral reefs sustain the livelihoods of millions of people worldwide and small island nations such as those in the Caribbean are especially dependent on them. However, these vital ecosystems have been rapidly declining, leading to loss of coral cover including keystone species like staghorn coral, Acropora cervicornis. High mortalities of staghorn coral over the last few decades have decimated populations and resulted in low genetic diversity among the surviving individuals. This decline has created the need for the restoration of this, where coral farming with the use of mid-water ocean nurseries has been proved to be an effective tool. Efforts to restore staghorn focus on optimizing growth conditions as well as identifying resilient and fast-growing genets. Factors such as depth, temperature, nursery structure and parent coral genotype have all been shown to affect the growth of staghorn coral within a nursery. The ability to quickly heal exposed skeletal tissue after fragmentation has also been an important factor in determining the successful restoration of staghorn.
The goal of this study was therefore to investigate the effect of source colony and position in a mid-water floating nursery tree, i.e tree branch position, on growth and healing of fragments from two neighboring source colonies of staghorn, located offshore of South Eleuthera, The Bahamas. Five centimeter pieces of two wild staghorn colonies (n = 10 each) were cut and placed on a nursery tree within The Bahamas Coral Innovation Hub nursery, located in South Eleuthera, The Bahamas. Total linear extension (TLE) was recorded after one year. Colony B had a higher average TLE (33.11 cm±10.36cm) than colony A (26.90 cm ± 5.31cm) and also developed more secondary polyps (Figure 1). Top fragments from both source colonies generated more secondary branches (66%) than the bottom. Therefore, implying both positions on the nursery tree and source colony influence the growth of A. cervicornis, with source colony having a higher influence. Higher growth rates at the top could be attributed to the proximity to sunlight, allowing for greater instances of photosynthesis. This indicates that restoration efforts should potentially focus on shallower ocean-based nurseries to allow for ample sunlight to reach the fragments and maximize growth. Efforts should focus on multiple source colonies to increase genetic diversity to increase resilience