In times of exacerbating biodiversity loss, reliable data on species occurrence are essential. Environmental DNA (eDNA) – DNA released from organisms into the water – is increasingly used to detect fishes in biodiversity monitoring campaigns. However, eDNA turns out to be capable of providing much more than fish occurrence data, including information on other vertebrates. A study, published in the open-access journal Metabarcoding and Metagenomics, demonstrates how comprehensively vertebrate diversity can be assessed at no additional costs.