Mark Stoeckle, together with co-authors Lyubov Soboleva (Hunter College) and Zachary Charlop-Powers (Rockefeller University), update their 2017 paper “Aquatic environmental DNA detects seasonal fish abundance and habitat preference in an urban estuary” (PLOS ONE e0175186). They extended their original six-month study to twelve months, making this one of the longest time series of fish monitoring by eDNA to date. The new analysis shows how little bits of DNA shed by fish track the seasonal movements of fish populations in and out of New York Harbor. eDNA also gives a picture of how the relative abundance of species differs from one habitat to another. These results help open our eyes to how eDNA can improve monitoring of ocean life.