Streamlining large-scale oceanic biomonitoring using passive eDNA samplers integrated into vessel's continuous pump...

Area of Science:

• Marine biology
• Environmental science
• Molecular ecology

Background:

• Scaling ocean biomonitoring is crucial for understanding marine ecosystems.
• Traditional water filtration for environmental DNA (eDNA) is time-consuming and limits large-scale application.
• Passive samplers offer a potential solution for efficient eDNA collection at sea.

Purpose of the Study:

• To evaluate a novel artificial sponge passive sampler for oceanic eDNA biomonitoring.
• To compare the performance of passive sampling with standard water filtration.
• To assess the feasibility of integrating passive samplers onto ocean-going vessels.

Main Methods:

• Deployment of artificial sponge passive samplers connected to underway seawater systems.
• Comparison with traditional water filtration methods across six locations from New Zealand to Antarctica.
• Eukaryote metabarcoding of the mitochondrial COI gene for biodiversity analysis.

Main Results:

• No significant difference in phylogenetic alpha-diversity between passive samplers and water filtration.
• Both methods showed decreasing Zero-Radius Operational Taxonomic Units (ZOTUs) with increasing latitude.
• Passive samplers detected more phyla and a higher estimated number of ZOTUs than filtration, despite higher replicate variability.

Conclusions:

• Artificial sponge passive samplers show promise for large-scale offshore marine eDNA biomonitoring.
• The technology can be integrated into existing ocean-going fleet operations without interference.
• Further improvements in passive sampler technology are needed to enhance replicate consistency and optimize biodiversity recovery.