July 17, 2020 — A recent test in Japan using environmental DNA (eDNA) to survey eel populations in rivers achieved similar detection rates to electro-shock fishing – without killing eels – and another test, on jack mackerel, improved estimation accuracy.
Molecular analysis of DNA left in the environment has proven to be an effective tool for detecting the presence of species, and is being applied more frequently in place of traditional survey fishing. It usually uses the polymerase chain reaction (PCR) process – a process also used in the COVID-19 antibody test – to rapidly duplicate genetic material to a quantity that can be effectively detected and identified. It has the advantage that it does not disturb or kill the fish – important for endangered species.