Early warning: detection of exotic Coho salmon (Oncorhynchus kisutch) by environmental DNA and evidence of establishment at the extreme south Patagonia

• Published in: Canadian Journal of Fisheries and Aquatic Sciences
• Main Authors: Chalde, Tomás, Nardi, Cristina Fernanda, Fernandez, Daniel Alfredo
• Format: Article in Journal/Newspaper
• Language: English
• Published: National Research Council Canada-NRC Research Press
• Subjects: EDNA; Patagonia; coho salmon; Beagle Channel; https://purl.org/becyt/ford/1.6; https://purl.org/becyt/ford/1; Austral; Argentina; Fernandez; Antártida; Tierra del Fuego
• Online Access: http://hdl.handle.net/11336/117163

The global expansion of aquaculture is a constant propagule pressure that enables the establishment of exotic species in freshwater and marine environments. Here, we provide the first report on the presence of exotic coho salmon (Oncorhynchus kisutch) at the extreme south of Patagonia, in the island of Tierra del Fuego (TDF). During the last 6 years, 43 juvenile coho salmon were captured along the Beagle Channel, while one adult was captured in fresh water. Scale analysis showed that migration from fresh water as smolt would occur during their first winter of life. Mitochondrial DNA analyses revealed two haplotypes previously reported in North America and a new haplotype not reported before. We developed an environmental DNA assay for detecting coho salmon DNA from fresh water, obtaining positive results in three rivers. Additionally, one of these rivers was monitored monthly for a year, and we detected coho salmon DNA over 7 months, revealing the probable occurrence of coho salmon juveniles in fresh water. These results suggest the potential establishment of self-sustaining populations of coho salmon in TDF. Fil: Chalde, Tomás. Universidad Nacional de Tierra del Fuego; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina Fil: Nardi, Cristina Fernanda. Universidad Nacional de Tierra del Fuego, Antártida e Islas del Atlántico Sur. Instituto de Ciencias Polares, Ambientales y Recursos Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Fernandez, Daniel Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina. Universidad Nacional de Tierra del Fuego, Antártida e Islas del Atlántico Sur. Instituto de Ciencias Polares, Ambientales y Recursos Naturales; Argentina