Determining the timing and location of fish reproductive events is crucial for the implementation of correct management and conservation schemes. Conventional methods used to monitor these events are often unable to assess the spawning activity directly or can be invasive and therefore problematic. This is especially the case when threatened fish populations are the study subject, such as the Arctic charr (Salvelinus alpinus L.) populations in Windermere (Cumbria, UK). Arctic charr populations have been studied in this lake since the 1940s, and the locations and characteristics of spawning grounds have been described in detail using techniques such as hydroacoustics, as well as physical and visual surveys of the lake bottom. Here, in conjunction with established netting surveys, we added an environmental DNA (eDNA) metabarcoding approach to assess the spatial distribution of Arctic charr in the lake throughout the year to test whether this tool could allow us to identify spawning locations and activity. Sampling was carried out between October 2017 and July 2018 at three locations in the lake, covering putative and known spawning .