Porites Coral Colony Recovery at Caño Island

Porites Coral Colony Recovery at Caño Island

Alvin Sherman Library

Coral reefs are essential marine ecosystems and Porites lobata is an important Eastern Pacific reef-building coral that plays a major role in reef structure and ecosystem stability. This project documents Porites lobata responses to impacts associated witl1 the 2023-24 El NiÑo-Southern Oscillation, comparing coral tissue condition from 2024 and 2025. Overlapping digital images (~500 each year) utilizing two GoPro Hero 11 cameras were obtained from one, large (~13 m²) Porites lobata colony at Caño Island, Costa Rica. The program Agisoft Metashape was used to generate a 3D photogrammetry model constructed from these digital images. Living, bleached and dead tissue areas were manually traced on the model and percent coverage was calculated utilizing the program TagLab. In 2024, the colony had 10.5% healthy living tissue, 65.0% bleached tissue, and 24.5% dead area. In 2025, there was a shift in tissue composition, with healthy living tissue rising to 57.0%, bleaching declining to 4.0%, and dead area increased to 39.0%. These results document a bleaching event in 2024 followed by split tissue recovery and mortality in 2025. Approximately half of the bleached tissue observed in 2024 recovered, and half suffered mortality. Monitoring coral species provides insight on how they respond under environmental stressors and in this colony Porites lobata demonstrated partial resilience.