CADIC   02618
CENTRO AUSTRAL DE INVESTIGACIONES CIENTIFICAS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
New establishment of a chinook salmon (Oncorhynchus tsawytscha) population in the extreme South Patagonia
Autor/es:
TOMÁS CHALDE; MIGUEL ANGEL CASALINUOVO; JAVIER HERNÁN ROJO; PAOLA AMANDA VILLATARCO; CLAUDIA CLEMENTINA BOY; SANTIAGO LESTA; DANIEL ALFREDO FERNANDEZ
Lugar:
Ciudad Autónoma de Buenos Aires
Reunión:
Congreso; Marine and Freshwater Invasive Species; 2016
Institución organizadora:
Aquatic Ecosystem Health & Management Society
Resumen:
Patagonian lakes and rivers are characterized by a long history of salmonid species introduction since early 20th century. At least nine fish species have been transplanted from North Hemisphere into Patagonia, mainly for sport fishing and aquaculture. Three of these species established successful populations in Tierra del Fuego (Salvelinus fontinalis, Salmo trutta and Oncorhynchus mykiss) while recently, in 2006, it has been described the first establishment of a chinook population in Lapataia River basin, flowing into the Beagle Channel. Chinook salmon is an anadromous species native from North Pacific basins that has been imported into Chile for ranching experiments in the 80?s, and later on dispersed into many rivers. Salmon runs have been observed for more than a decade in the Grande River, an Atlantic basin of Tierra del Fuego. The aim of this study was to check the establishment of a self-sustaining population of this species in this river, to characterize its life history and to compare it with the population of Lapataia River. The life history of this population was studied from scale reading of adults captured by anglers since 2013. In April of 2014 and 2015 surveys across the Grande River were conducted to study the presence of chinook juveniles. Three native (Galaxias maculatus, Geotria australis and Eleginops maclovinus) and three salmonids species (S. trutta, O. mykiss and O. tshawytscha) were captured by electrofishing. Chinook juveniles were classified as stream-ecotype, with seaward migration after a full year in the river, while adults spent 2-3 years at sea before returning during springtime and spawning at the headwaters. These results showed differences with the Lapataia population where stream- and ocean-type salmon were recorded and adults returned during fall and spawned near the river mouth. These data provide key information to understand the dispersion of this exotic species.