Defense Date
8-4-2025
Document Type
Thesis
Degree Type
Master of Science
Degree Name
Marine Science
First Advisor
Joana Figueiredo, Ph.D.
Second Advisor
Nicole D. Fogarty, Ph.D.
Third Advisor
Tammy Frank
Keywords
aquaculture, coral, juvenile, light, restoration, spectrum
Abstract
For at least half a century, numerous direct and indirect anthropogenic stressors have led to the decline of coral populations globally. To minimize this decline and preserve genetic diversity, land-based nurseries have been sexually propagating corals to repopulate reefs. While the techniques to induce corals to spawn and rear their larvae are relatively well-established, the grow-out, i.e. rearing from newly settled to a size suitable for outplanting, remains yet to be fully optimized. Specifically, light spectrum, food quantity and quality and algal control require optimization. This study investigated the post-settlement survival and growth of the Caribbean reef building corals Colpophyllia natans and Pseudodiploria strigosa under three light spectra: (1) near surface (natural sunlight), i.e. outdoors grow-out at land-based nurseries; (2) 10m reef depth (using radion lights); (3) blue-shifted (using radion lights) peaking between 400-450nm. This experiment was conducted at both Nova Southeastern University and The Florida Aquarium using the same larval cohort. All treatments underwent the same irradiance biweekly increase from 25 µmol photons m-2s-1 at week 0 to 200 µmol photons m-2s-1 at week 19. After seven months, the blue-shifted spectrum presented the highest survival rates for both species. Reef-mimic spectrum produced comparable growth to blue-shifted for P. strigosa. Reef-mimic spectrum provided a size advantage over blue-shifted for C. natans. The near-surface spectrum treatments performed poorly leading to smaller sized corals. The findings from this study will help inform future aquaculture practices for coral restoration efforts by identifying the benefits and detriments of multiple light spectra during coral grow-out.
NSUWorks Citation
Liam A. Abrams. 2025. Optimization of Light Spectrum During the Early Grow-out of Caribbean Corals. Master's thesis. Nova Southeastern University. Retrieved from NSUWorks, . (215)
https://nsuworks.nova.edu/hcas_etd_all/215.