September 29, 2026
Environmental DNA: How eDNA Helps Ocean Conservation
Estimated reading time: 0 minutes
BY: Liv Ward
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What is Environmental DNA (eDNA)?
Environmental DNA (eDNA) is the genetic material shed by organisms in their environment. This material comes from skin cells, scales, mucus, feathers, waste and other biological matter left by species in their surroundings. Once released, eDNA remains in the environment before breaking down due to sunlight, microbes, and water conditions. By collecting eDNA from water, air and soil, scientists can detect species, monitor biodiversity and better understand ecosystems.
How Does Environmental DNA (eDNA) Work?
1) Sample Collection
Scientists collect water samples from specific ocean locations to capture eDNA from nearby organisms. Niskin bottles are typically attached to a CTD rosette, closing at different depths to collect water samples throughout the water column. Samples are carefully labeled by depth, location, date, environmental conditions, as well as the water temperature and salinity.
2) Filtration
Scientists filter collected samples to separate genetic material (DNA) shed by species in the area from sediment and water.
3) Preservation
eDNA samples are safely stored and either frozen or preserved in a buffer, which prevents degradation. This allows DNA to be stored for several years.
4) Analysis
Scientists compare DNA sequences to reference databases to identify which species are present in a sample. This information is then used to identify patterns in species presence, distribution, and diversity.
5) Interpretation
Scientists look for patterns to provide insight into the ocean environment and help better understand marine species and ecosystems.
6) Reporting
Reports summarize which species were detected, where samples were collected and how biodiversity varies across locations and over time. These findings support ongoing monitoring of the ocean ecosystem. As climate change affects the ocean, long-term monitoring is becoming increasingly important.
Why Environmental DNA (eDNA) Matters in Canada?
Canada’s vast and diverse ocean ecosystems make eDNA a valuable tool for monitoring species, biodiversity and marine habitats. Here are three ways eDNA can support ocean conservation in Canada:
- Tracking biodiversity in Canada: eDNA provides a snapshot of biodiversity and how species and communities change over time. It can help map biodiversity across different marine habitats.
- Detection of rare, endangered or invasive species: eDNA research can detect species that might otherwise go unnoticed in other traditional marine research methods such as drop cameras.
- Species mapping: eDNA can help scientists track where marine species occur and understand their geographic distribution and associated habitats.
How Environmental DNA Helps Ocean Conservation
eDNA helps scientists better understand marine biodiversity and the habitats that support a healthy ocean. This evidence can help identify ecologically important areas and inform science-based ocean protection decisions.
On a recent expedition to the Southern Newfoundland Slope, led by Oceana Canada and Fisheries and Oceans Canada, scientists gathered eDNA. Only now are scientists revealing this area’s remarkable biodiversity, documenting deep-sea species humans rarely have the chance to see.
Learn more about the Southern Newfoundland Slope expedition. >>>
What is Environmental DNA (eDNA)?
Environmental DNA (eDNA) is the genetic material shed by organisms in their environment. This material comes from skin cells, scales, mucus, feathers, waste and other biological matter left by species in their surroundings. Once released, eDNA remains in the environment before breaking down due to sunlight, microbes, and water conditions. By collecting eDNA from water, air and soil, scientists can detect species, monitor biodiversity and better understand ecosystems.
How Does Environmental DNA (eDNA) Work?
1) Sample Collection
Scientists collect water samples from specific ocean locations to capture eDNA from nearby organisms. Niskin bottles are typically attached to a CTD rosette, closing at different depths to collect water samples throughout the water column. Samples are carefully labeled by depth, location, date, environmental conditions, as well as the water temperature and salinity.
2) Filtration
Scientists filter collected samples to separate genetic material (DNA) shed by species in the area from sediment and water.
3) Preservation
eDNA samples are safely stored and either frozen or preserved in a buffer, which prevents degradation. This allows DNA to be stored for several years.
4) Analysis
Scientists compare DNA sequences to reference databases to identify which species are present in a sample. This information is then used to identify patterns in species presence, distribution, and diversity.
5) Interpretation
Scientists look for patterns to provide insight into the ocean environment and help better understand marine species and ecosystems.
6) Reporting
Reports summarize which species were detected, where samples were collected and how biodiversity varies across locations and over time. These findings support ongoing monitoring of the ocean ecosystem. As climate change affects the ocean, long-term monitoring is becoming increasingly important.
Why Environmental DNA (eDNA) Matters in Canada?
Canada’s vast and diverse ocean ecosystems make eDNA a valuable tool for monitoring species, biodiversity and marine habitats. Here are three ways eDNA can support ocean conservation in Canada:
- Tracking biodiversity in Canada: eDNA provides a snapshot of biodiversity and how species and communities change over time. It can help map biodiversity across different marine habitats.
- Detection of rare, endangered or invasive species: eDNA research can detect species that might otherwise go unnoticed in other traditional marine research methods such as drop cameras.
- Species mapping: eDNA can help scientists track where marine species occur and understand their geographic distribution and associated habitats.
How Environmental DNA Helps Ocean Conservation
eDNA helps scientists better understand marine biodiversity and the habitats that support a healthy ocean. This evidence can help identify ecologically important areas and inform science-based ocean protection decisions.
On a recent expedition to the Southern Newfoundland Slope, led by Oceana Canada and Fisheries and Oceans Canada, scientists gathered eDNA. Only now are scientists revealing this area’s remarkable biodiversity, documenting deep-sea species humans rarely have the chance to see.
Learn more about the Southern Newfoundland Slope expedition. >>>
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