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Environmental DNA (eDNA)

Summary

Marine environments and organisms continue to be impacted by a myriad of factors. While marine organisms can be challenging to access and assess, all organisms shed their DNA, referred to as environmental DNA (eDNA), which can assist in detection of organisms without having to capture them. Our eDNA projects have developed faster, cheaper, and more sensitive approaches for collecting biological baselines and measuring how shifts in biodiversity composition occur over time.
 
Developing eDNA techniques allows for streamlined sampling of species and ecosystems worldwide, putting the evidence on the table for the relevant agencies, parties, and the public to consider for more informed and transparent decision-making. In partnership with management agencies, multiple institutions, engineers and scientists, COS is developing novel genetic techniques to more efficiently track biodiversity and species abundance in the ocean.

Process

Across multiple eDNA projects, COS has contributed to the science and optimization of technologies to collect eDNA samples and ground truth DNA identification with biodiversity assessments to inform ecosystem monitoring and management needs.

2012-2014

In collaboration with the Monterey Bay Aquarium, COS tested the potential to detect eDNA from multiple species simultaneously in the Open Sea Exhibit, a 1.2 million gallon seawater tank at the Monterey Bay Aquarium (Kelly et al., 2014).

2014-2016

Additional collaborations between COS, the Monterey Bay Aquarium, Hopkins Marine Station, and Stanford enabled COS staff to break new ground in using eDNA for biodiversity detections in marine environments. eDNA detections in the wild kelp forest of Monterey Bay were comparable to those observed via SCUBA visual surveys done by SCUBA divers (Port et al. 2016).

Experiments conducted at Hopkins Marine Station distinguished differences in the shedding and persistence rates of the eDNA of anchovies, sardines and mackerel, three commercially and ecologically important fish species. Anchovy, sardine and mackerel DNA persisted on the order of days, suggesting eDNA is a promising tool for efficiently and effectively tracking fish in marine waters (Sassoubre et al., 2016).

2015-2020

COS collaborated with the National Oceanic and Atmospheric Administration as well as partners at multiple institutions to implement eDNA monitoring in both the Florida Keys and Monterey Bay National Marine Sanctuaries. As part of the five-year Marine Biodiversity and Observation Network (MBON) Sanctuaries Project, we collected eDNA baselines (Andruszkiewicz et al., 2017; Kelly et al., 2017; Sawaya et al., 2019; Closek et al., 2019; Djurhuus et al., 2020) and determined standardized eDNA methods (Djuhuus et al., 2017).

Additionally, we identified that eDNA data can add organismal detections to standard monitoring methods (Kelly et al., 2017). We used standard survey and eDNA methods to observe different distribution patterns of marine vertebrates in the central California Current Ecosystem during a warmer el Niño year versus when typical ocean conditions returned (Closek et al., 2019). We identified seasonal patterns of organisms in Monterey Bay and networks of organisms (from bacteria to vertebrates), which highlighted potential key organisms that could serve as indicators of the ecosystem’s state (Djurhuus et al., 2020).

Current Projects

More information about our current eDNA work.

Resources

Environmental DNA 2016 Fact Sheet 

COS News Stories, Publications and Related Webpages

Media Coverage

Publications