Environmental DNA (eDNA) Testing
Environmental DNA (eDNA) testing is a scientific tool available to augment, or replace conventional ecological survey methods for the detection of species of management interest.
eDNA refers to the genetic material (nuclear, mitochondrial or chloroplast DNA) that is released by an organism (as gametes, dead skin cells, feces, urine, mucous, etc.) to its environment and can be collected from that environment using water, sediment, or soil sampling.
Maxxam tests eDNA for target species using quantitative PCR (qPCR) assays that have been thoroughly validated for both specificity and sensitivity.
eDNA is particularly advantageous for detecting species that are of low population density and hard to observe using conventional methods. This is true for species at risk and early detection of invasive species.
Advantages of eDNA compared to conventional survey methods:
- Improved sensitivity – eDNA detects cryptic and low density species with greater sensitivity;
- Accurate – properly designed eDNA tests are specific to the target species not requiring a qualified expert in the field to identify the species;
- Time savings – reduced field time with eDNA sampling compared to conventional methods;
- Cost effective – ecological surveys can be completed faster and multiple target species can be tested from a single eDNA sample;
- Less invasive – eDNA replaces trapping/electrofishing and reduces the impact to sensitive habitats, including less risk of pathogen transfer;
- Permit and license not required – eDNA sampling does not require a permit;
- Reduced observer bias – eDNA sampling reduces error associated with observer experience or variation in surveying efforts;
- Improved field safety – field sampling can occur during daylight hours and better weather conditions;
- Expanded window of surveying – eDNA sampling can be completed outside of conventional restraints, e.g., window of amphibian calling;
- Option for future testing – properly archived eDNA samples can be tested at a future date for additional species of interest without the need to recollect samples from the field.
- eDNA sampling, filtration and preservation article
- Important Considerations for eDNA Sampling, Filtration and Preservation Video