eDNA metabarcoding as a biomonitoring tool for marine protected areas

Area of Science:

• Marine Biology
• Ecosystem Management
• Molecular Ecology

Background:

• Marine protected areas (MPAs) require effective monitoring for ecosystem management.
• Current SCUBA-based visual surveys are costly, time-consuming, and limited in scope.
• Environmental DNA (eDNA) metabarcoding offers a promising, less resource-intensive alternative.

Purpose of the Study:

• To compare the effectiveness of eDNA metabarcoding and underwater visual census for monitoring fish communities.
• To assess the strengths and limitations of eDNA metabarcoding against traditional survey methods.
• To evaluate eDNA's ability to detect fish species composition inside and outside MPAs.

Main Methods:

• Collected water samples for eDNA metabarcoding within Scorpion State Marine Reserve.
• Conducted paired underwater visual census surveys concurrently.
• Utilized MiFish 12S metabarcoding for fish species identification.

Main Results:

• eDNA captured 76% of observed fish species and 95% of genera during visual surveys.
• eDNA identified 23 additional species not detected by concurrent visual surveys.
• eDNA detected significant variations in fish communities based on location and site, demonstrating high sensitivity.

Conclusions:

• eDNA metabarcoding is a sensitive and effective tool for monitoring marine fish communities.
• eDNA serves as a valuable complementary method to traditional visual surveys in MPAs.
• eDNA metabarcoding can detect subtle ecological patterns crucial for marine ecosystem management.