Coral Resilience on Koh Tao

Madalena working on some of her reef surveys

Madalena working on some of her reef surveys

Scientists and local stakeholders are racing to protect coral reefs as climate change threatens their survival everywhere around the globe. One of the techniques often utilized is the creation of Marine Protected Area (MPAs) to manage the resources and ensure protection or sustainable use. On Koh Tao different coastal management plans have been proposed since 1987, but the first real progress towards creating MPA sites started in 2012. But, with global reef decline at over 2% per year, triage must be done to protect the most vulnerable or valuable reefs first. But how can managers know which reefs are most in need of protecting, and how should the MPAs be set-up in each unique reef to ensure that the efforts are successful?


In early 2014, Madalena Cabral joined the NHRCP conservation team as an intern while she also worked on a Maters Thesis project with the University of Lisboa. Over the course of 5 months, Madalena completed reef surveys around the island using the specialized methods developed by the IUCN to evaluate coral reef resilience using a wide range ecological, physical, and anthropogenic factors. The resilience of a coral reef is basically its ability to withstand or rebound from any major disturbances like bleaching, disease outbreak, predator outbreaks, etc. Her data and findings are not only important to understanding the current state of the reefs around the island, but also gives recommendations on what should be done to manage them for the future.


Her full thesis titled “Resilience-based assessment for targeting coral reef management strategies in Koh Tao, Thailand” can be downloaded here.


Over the time she was here, Madalena managed to collect enough surveys, with the help of other members from our team, to analyze 14 sites around the island. The resilience score for each site ranged from 2.96 to 3.54. The 3 most resilient sites around the island where White Rock, Hin Ngam, and Shark Island; and the 4 lowest scores where for Tao Tong, Japanese Gardens, and Sairee.  The sites with the lowest scores had more threats present, less resilient coral genera, and less recovery from past events, as can be seen in the table below.


Cabral_2014_Resielence of Koh Taos Reefs using IUCN method-30

Madalena looked at the high resilience sites with high biodiversity of corals and found that three of them are currently not included in marine protected areas but should be (Hin Ngam, Tanote, Ao Leuk). Hin Wong, one of the few sites with a high abundance of Acropora corals, should also be included for protection. In her conclusion, she also outlined several other important findings and recommendations for changes to the current MPA status of sites around the island.


Madalena’s project continues to further the efforts the research we have been doing here for nearly a decade and moving them into policy recommendations that can help protect our local reefs for the future. Projects like this are an important part to ensuring the sustainability of our marine resources, in a world where more than 1.6 billion people currently living along tropical coasts.


Really great work Madalena! It was great to have you in our program, and we hope that you maintain your enthusiasm and passion for marine conservation to help lead us all towards a better future.

Don’t forget to download her full paper and see more of the projects and papers from our past students and interns on our website.