Marissa McMahan

Director of Fisheries

Environmental DNA, or eDNA, is a new research and monitoring tool that Manomet uses in our fisheries and shorebirds research. All organisms shed DNA – in the form of scales, gametes, waste products, and more. By analyzing water and sediment samples, we can match DNA found in the samples to that of species of interest, allowing us to learn more about species distribution and population abundance. For our fisheries research, we are focused on river herring and shellfish. The mapping of the human genome was a huge breakthrough less than 20 years ago; now, the process of mapping genomes has become routine and the genomes of thousands of species are available from a federal database.

The benefits of eDNA analysis include the ability to detect species occurring at low levels of abundance and monitoring larval stages that are difficult to identify to the species level. Because the process can be completed in a noninvasive way without handling organisms, it is also ideal for monitoring juvenile river herring, which often don’t survive being netted, and endangered species, including Atlantic salmon, which must be handled as little as possible.