The complete history of salmonid introductions in the Kerguelen Islands, Southern Ocean

• Published in: Polar Biology
• Main Authors: Lecomte, Frédéric, Beall, Edward, Chat, Joëlle, Davaine, Patrick, Gaudin, Philippe
• Other Authors: Ministère des Ressources naturelles du Québec, Université de Québec, Institut National de la Recherche Agronomique (INRA), Ecologie Comportementale et Biologie des Populations de Poissons (ECOBIOP), Institut National de la Recherche Agronomique (INRA)-Université de Pau et des Pays de l'Adour (UPPA), We gratefully acknowledge the support (funding, logistics, travel) provided by the TAAF administration (Terres Australes et Antarctiques Françaises-Mission de Recherche) and by the Polar Institute (IPEV, Institut Polaire Paul-Emile Victor, formerly IFRTP, Institut Français de Recherche et de Technologie Polaire) over all these years and their staff in Paris, La Réunion and Brest, France.
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2013
• Subjects: introduction; colonization; salmo; salvelinus; kerguelen island; oncorhynchus; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; Kerguelen; Kerguelen Island; Kerguelen Islands; Southern Ocean; Polar Biology
• Online Access: https://hal.inrae.fr/hal-02647667; https://doi.org/10.1007/s00300-012-1281-5

International audience Since the early 1950s, several species of salmonids have been introduced more or less successfully in the Kerguelen Islands, a 7,215 km² archipelago located in the Southern Ocean (49°S, 70°E) and previously devoid of any freshwater fish. The aim of this work was to establish a documented chronicle of these events from available archives, to better understand the causes of the colonization failure or success for the different species. The history that emerged from the analysis of the archives appeared much more complex than previously published. Stocks of various origins were used, and numerous attempts were made at different sites involving variable numbers of fish released at different life stages. Between 1951 and 1991, 22 importation attempts took place, involving about 2 million individuals. Of the 8 species introduced (Salmo trutta, S. salar, Oncorhynchus mykiss, O. tshawytscha, O. kisutch, Salvelinus namaycush, S. fontinalis and S. alpinus), only 3 failed to establish local populations (O. mykiss, O. tshawytscha and S. namaycush). Overall, 23 watersheds were stocked. At present, 45 watersheds are colonized by one or several species. S. trutta, S. fontinalis, S. alpinus and O. kisutch were capable of migrating toward new habitats. The brown trout (S. trutta) was the only species to colonize a large number of watersheds (32 in about 10 generations). Its success can be explained by the diversity of origins, the number and importance of introduction and transfer attempts, the diversity of release sites and the peculiarities of its life cycle