Monitoring Attempted Eradication of the Invasive Species Northern Pike (Esox lucius), and Re-Establishment of Three-Spined Stickleback (Gasterosteus aculeatus) in Gillsvann, using eDNA Analysis.

Anthropogenic activities are putting marine and freshwater ecosystems under increasing pressure and global climate change is causing transformations in ecosystems and food chains worldwide. Invasive species pose one of the greatest threats to natural diversity and the endemic species essential for ecosystem balance. In November 2021, Gillsvann in Kristiansand, Norway, was treated with rotenone with the aim of eradicating the invasive species Northern pike (Esox lucius) from the lake. The effectiveness of the treatment was monitored using environmental DNA (eDNA) analysis. The primary objective was to investigate the presence of Northern pike eDNA in the lake from November 2021 (after the tr…