Regional Survivorship, Predation and Growth of Outplanted Fragments from Resilient Orbicella Faveolata in Southeast Florida
Location
HCAS Guy Harvey Oceanographic Center, Nova Southeastern University
Start
2-13-2025 3:45 PM
End
2-13-2025 4:00 PM
Type of Presentation
Oral Presentation
Abstract
Over 150 corals >2m in diameter reside in southeast Florida’s nearshore habitats, the majority being Orbicella faveolata dating up to 320 years old. Since 2015, many have died or experienced significant tissue loss due to stressors caused by stony coral tissue loss disease (SCTLD). Fragments broken from healthy-looking colonies with a low probability of survival were collected to aid in restoration of recently dead colony surfaces. Fragments were microfragmented and maintained in an ex-situ nursery until ready for outplanting. Predation, survival, growth, and disease occurrence of outplanted O. faveolata fragments across three experimental outplanting phases were conducted in February 2023, December 2023 and May 2024. Each phase adapted different outplanting methods to address challenges encountered in previous phases. Phase 1 involved countersinking fragments of two different sizes into coral skeletons and experienced high removal and predation, particularly for fragments smaller than 1.5 cm2. To mitigate these issues, Phases 2 and 3 employed larger fragments (~4cm2) countersunk in cement domes and utilized biodegradable PHA tubes for protection from fish predation. Phase 2 included a spatial component by outplanting fragments to eight colonies across Fort Lauderdale and Biscayne regions. However, Phase 2's PHA protection was compromised by extreme weather. Phase 3 addressed this problem by using thicker PHA tubes to assess their effectiveness. Predation in Phase 2 varied significantly across monitoring periods, peaking at 5.2% one-month post-outplanting. Fragments in Fort Lauderdale exhibited significantly higher predation probability. Time of year, region and genotype also influenced fragment’s daily growth rate. In Phase 3, the PHA structures demonstrated improved success, with most remaining intact beyond the peak predation period. Consequently, fragments protected by PHA structures exhibited lower predation rates compared to controls. Daily growth rate significantly varied with time of year and genotype. However, a potential disease outbreak resulted in substantial outplant mortality. Understanding these factors is important for improving outplanting protocols. The fragments propagated from these massive colonies are an important genetic stock of disease-resistant donors for future restoration efforts. This project will help optimize the use of corals of opportunity to hopefully produce a generation of disease resistant corals.
Regional Survivorship, Predation and Growth of Outplanted Fragments from Resilient Orbicella Faveolata in Southeast Florida
HCAS Guy Harvey Oceanographic Center, Nova Southeastern University
Over 150 corals >2m in diameter reside in southeast Florida’s nearshore habitats, the majority being Orbicella faveolata dating up to 320 years old. Since 2015, many have died or experienced significant tissue loss due to stressors caused by stony coral tissue loss disease (SCTLD). Fragments broken from healthy-looking colonies with a low probability of survival were collected to aid in restoration of recently dead colony surfaces. Fragments were microfragmented and maintained in an ex-situ nursery until ready for outplanting. Predation, survival, growth, and disease occurrence of outplanted O. faveolata fragments across three experimental outplanting phases were conducted in February 2023, December 2023 and May 2024. Each phase adapted different outplanting methods to address challenges encountered in previous phases. Phase 1 involved countersinking fragments of two different sizes into coral skeletons and experienced high removal and predation, particularly for fragments smaller than 1.5 cm2. To mitigate these issues, Phases 2 and 3 employed larger fragments (~4cm2) countersunk in cement domes and utilized biodegradable PHA tubes for protection from fish predation. Phase 2 included a spatial component by outplanting fragments to eight colonies across Fort Lauderdale and Biscayne regions. However, Phase 2's PHA protection was compromised by extreme weather. Phase 3 addressed this problem by using thicker PHA tubes to assess their effectiveness. Predation in Phase 2 varied significantly across monitoring periods, peaking at 5.2% one-month post-outplanting. Fragments in Fort Lauderdale exhibited significantly higher predation probability. Time of year, region and genotype also influenced fragment’s daily growth rate. In Phase 3, the PHA structures demonstrated improved success, with most remaining intact beyond the peak predation period. Consequently, fragments protected by PHA structures exhibited lower predation rates compared to controls. Daily growth rate significantly varied with time of year and genotype. However, a potential disease outbreak resulted in substantial outplant mortality. Understanding these factors is important for improving outplanting protocols. The fragments propagated from these massive colonies are an important genetic stock of disease-resistant donors for future restoration efforts. This project will help optimize the use of corals of opportunity to hopefully produce a generation of disease resistant corals.