The expansion of exotic Chinook salmon (Oncorhynchus tshawytscha) in the extreme south of Patagonia: an environmental DNA approach

NARDI, CRISTINA F; FERNANDEZ, DANIEL ALFREDO; VANELLA, FABIÁN ALBERTO; CHALDE, TOMÁS

BIOLOGICAL INVASIONS

SPRINGER

Lugar: Berlin; Año: 2019

1387-3547

Theability to detect species at low densities greatly improves thesuccess of management action on alien in vasivespecies (AIS) and decreases their possible impact on ecosystems. Inthe last two decades, exoticChinooksalmon(Oncorhynchus tshawytscha)has established populations in both Pacific and Atlantic river basinsof Patagonia. The last established populations have been reported atthe extreme south Patagonia, in the island of Tierra del Fuego (TDF).In order to obtain information on the distributionofthis AIS, wedeveloped a detection method based on environmental DNA (eDNA) tomonitor Chinook salmon expansioninTDF. First, wedesigned Chinook salmon specific primers with no cross-amplificationwith DNA from other species living at the same environment. Second,we attempted to detect Chinook salmon DNA from natural environmentsat the same time that we performed conventional survey byelectrofishing. Finally, weused a Real Time PCR assay to amplify Chinook salmon DNA obtainedfrom water samples from 10 river basins and one estuary within TDFand one river basin from Isla de los Estados. We were able to detectChinook salmon DNA from 8 rivers and from the estuary in TDF. As aresult, the eDNA-based method allowed us to confirm the expansion ofChinook salmon since its first report in TDF. p { margin-bottom: 0.21cm; direction: ltr; line-height: 115%; text-align: left; }p.western { font-family: "Calibri", serif; font-size: 11pt; }p.cjk { font-family: "Calibri"; font-size: 11pt; }p.ctl { font-family: "Times New Roman"; font-size: 11pt; }a:link { color: rgb(0, 0, 255); }</div></body></html>