Who?I am a French PhD student at the MARine Biodiversity Exploitation and Conservation (MARBEC) laboratory, in the Universit� de Montpellier. We are working in collaboration with Louis Bernatchez at the Universit� Laval. We will also collaborate with two groups of explorers, �La Voie Arctique� and �Le Vagabond�, who will sail on the arctic seas this summer. Both boats were designed to reduce all pollution and greenhouse gas emissions. What?Our goal is to sample environmental DNA (eDNA) in the Arctic regions of Canada, with a protocol completely carried out offshore (2 different boats). One boat will host 3 persons, the other one will host 4 persons. No facilities will be constructed. The analysis of eDNA will be carried out in France, and results will be shared with local communities and published in an open access journal. Sampling eDNA only requires to filter surface seawater: indeed, it has no impact on wildlife, it doesn�t affect the species behavior and provides better results than most conventional survey methods.Why?We hope to survey marine fish communities in coastal waters, in order to detect early species arrivals due to climate change. This region is one of the less surveyed on the globe, but also the region where climate change will have the strongest effects, and thus we expect strong changes in the fish communities. We believe it is of great importance to study the area to know which marine fish species are present in the local communities. Where?One of the boats will sail from Sachs Harbour (Inuvialuit), to Greenland, thus passing through Nunavut in its northernmost parts, and the second boat will sail in the Baffin Sea, from Grise Fiord to Saint Pierre & Miquelon. The Vagabond will pass near 6 local communities: Iqaluit, Pangnirtung, Qikiqtarjuaq, Clyde River, Pond Inlet, and Grise Fiord.When?The Vagabond boat will start from Grise Fiord in early September, while La Voie Arctique will start from Sachs Harbour in June, and get to Nunavut as soon as the weather and the winds allow.