NOAA Fisheries –
Tiny bits of DNA collected from waters off the West Coast allowed scientists to identify more species of marine vertebrates than traditional surveys with trawl nets. They also reflect environmental shifts such as unusual ocean temperatures that affect the organisms present, new research shows.
The findings published in Frontiers in Marine Science demonstrate that environmental DNA, or eDNA, can add valuable detail to longstanding marine surveys. They revealed the presence of important species that usually evade trawl nets such as great white sharks and salmon. Ongoing collection of eDNA can also help detect environmental changes when marine life shifts habitat with changes in the ocean, the study found.
“eDNA is adding details that we might not get any other way, and giving us a more complete picture,” said Collin J. Closek, an Early Career Science fellow at the Center for Ocean Solutions at Stanford University. Closek is lead author of the paper with other scientists from Stanford University, University of California Santa Cruz, and NOAA’s Southwest Fisheries Science Center.
Marine life constantly sheds bits of genetic material into surrounding water. eDNA techniques capture that DNA from water samples and identify the species it comes from. New laboratory sequencing methods help scientists examine many samples at once. They have made eDNA an increasingly powerful tool for detecting the range of species that have passed through the water.