UNESCO in report titled ‘Engaging Communities to Safeguard Ocean Life’ based on eDNA expeditions, highlights vulnerability of marine species as oceans warm.

About UNESCO’s eDNA Expeditions

• Global citizen science initiative that measures marine biodiversity and assess impacts of climate change on species distribution across UNESCO WHMS.
• eDNA sampling campaigns were organized across 21 of 51 UNESCO’s WHMS between September 2022 and July 2023.

About eDNA

• Defined as genetic material left by organisms in environment. It includes DNA from cells, tissues, fluids, and excrement which can be collected and detected from environment samples.

Significance of eDNA

• Large scale: eDNA sampling is possible for geographically distant and vast areas.
• Robust technology: It is a highly sensitive and rapid method compared to other bio-monitoring methods.
• Sustainable: Non-invasive method, thus lesser impact on environment.
• Others: Cost-effective sampling collection, ability to detect rare, transient and invasive species. E.g. Detection of invasive lionfish in Belize.

Limitations of eDNA

• Limited data provided: eDNA only confirms presence and does not capture number, size, sex, or life stage of detected organisms. 
• Identification: Absence of many species in DNA reference databases, leading to identification issues.
• Others: Prone to contamination; High costs of sampling analysis in labs.