- Somkiat Khokiattiwong & Wenxi Zhu
- Posted on
- Phuket, Thailand
On 27-29 November 2023, the IOC Sub-Commission for the Western Pacific (WESTPAC) in partnership with the Marine and Coastal Resources Research and Development Institute (Thailand) and the Nanjing University (China), organized a training workshop at the Phuket Marine Biological Center, Thailand to introduce about the Environmental DNA (eDNA) method, and explore how it could be used for researching and monitoring marine biodiversity in coastal habitats.
“We cannot manage well what we don’t know!” The training workshop truly marked a resounding start forward in using eDNA for marine biodiversity monitoring in the region. It is the first ever training workshop organized in the region focusing on using eDNA for monitoring marine biodiversity, with overwhelming interests received from resource managers, conservation practitioners and researchers from the region. The workshop received technical support from the Nanjing University.
Home to the highest level of marine biodiversity and endemism in the world, the whole Southeast Asia and its adjacent areas rely heavily on coral reefs, seagrass beds and mangroves – critical habitats for maintaining its magnificent marine biodiversity that support sustainable livelihoods and economy. While the human activities and climate change have been escalating, our conservation efforts have been constrained by conventional methods for monitoring marine biodiversity (species diversity, richness, distribution and their migration patterns), as they are difficult to scale up to cover the entire coastline of countries.
Environmental DNA (eDNA) is the genetic material that has been shed from organisms into the surrounding environment, such as water, soil, or air. It can be collected from a variety of sources, including water samples, sediment samples, and even filter papers that have been used to filter water. Environmental DNA (eDNA) metabarcoding is a novel method of assessing biodiversity. When samples are taken from the environment, DNA is extracted, and amplified using general or universal primers in polymerase chain reaction and sequenced using next-generation sequencing to generate thousands to millions of reads. From this data, species presence can be determined, and overall biodiversity assessed.
Environmental DNA (eDNA) has recently attracted considerable attention for its potential in measuring marine biodiversity, due to its cost effectiveness and without the need to extract organisms from their environment. However, it also has some limitations, such as inadequate regional fish barcode data, limited sampling efficiency and laboratory protocols, the eDNA-based fish monitoring has been gradually applied in different marine ecosystems, with significant improvement made in the last few years.
The training workshop featured cutting-edge lectures on the first day about the theory and methods of eDNA biomonitoring and its application, principle and technical guidelines of field sampling and lab preparation, data processing and analysis.
Thanks to the tremendous support of the Thailand’s Department of Marine and Coastal Resources, a field cruise was arranged on the second day to take all participants to the ocean for practical hands-on training on large volume sampling and post-processing of samples in the reef area of Racha Island, Hae Island and PMBC’s coastal waters.
The last day of the training workshop was dedicated to national/institutional reports about eDNA research status in each country, and a brainstorming session where participants shared their experiences, discussed the challenges and opportunities of eDNA monitoring, and explored the potential for collaborations in the region.
There was a consensus that the benefit of using eDNA for biomonitoring is immense, but capacity disparities are also evident given it is a novel technology. Participants decided to take a demonstration approach to the eDNA program development, with a view to improving eDNA biomonitoring capacity through learning-by-doing process, and generating useful results for marine biodiversity consideration, resource or marine protected areas management.