Non-native anadromous salmonids in the La Plata Basin: long distance colonization?

LUIS ALBERTO ESPÍNOLA; CLAUDIO BAIGÚN; CARLA RIVA-ROSSI; PAMELA QUIROGA; ELIE ABRIAL; ANA PIA RABUFFETTI; MARTÍN CESAR MARIA BLETTLER; LUCIANO NEVES DOS SANTOS

BioInvasions Records

Regional Euro-Asian Biological Invasions Centre - REABIC

Lugar: Helsinski; Año: 2023 vol. 13 p. 251 - 265

The introduction and dispersal of salmonids have been widespread in Patagonian basins, including anadromous species such as Chinook salmon (Oncorhynchus tshawytscha), rainbow trout or steelhead (O. mykiss), sea-run brown trout (Salmo trutta), and, to a lesser extent, coho salmon (Oncorhynchus kisutch). In recent years, Chinook salmon and steelhead have been reported in the Paraná and Uruguay rivers and in the estuary of La Plata River. This could be a result of long-distance movements, where stray individuals travel northward along the cold Malvinas current. They enter these rivers when it collides with the warm current originating from Brazil. However, this entry takes place within a specific timeframe when the water temperature remains below its lethal thermal threshold. Due to this temperature constraint and their reproductive characteristics, the introduction of salmonids into this basin would not present a risk to the native species. The projected impact of climate change, which anticipates an increase in river temperatures and a southward shift of the Brazilian current, would further support this hypothesis