Our study is based on a tremendous (n=168) and unique data set of otolith elemental concentration characterized by the Magnesium 24 (Mg μg/g), Strontium 88 (Sr μg/g) and the Barium 138 (Ba μg/g) extracted from Greenland halibut Reinhardtius hippoglossoides living in the Saguenay Fjord, Estuary and Gulf of St. Lawrence caught during the summer 2016 mission using an Alfredo III bottom otter trawl. Information about Greenland halibut such as length (mm), weight (g), capture site, depth and date were added. The otolith section (margin or core) analyzed was specified. The objective was to explore the spatial variation of the elemental fingerprints in the Estuary and Gulf of St. Lawrence and to determined the connectivity and natal source of our individuals. The elemental sectors were determined based on elemental fingerprint similarites and the natal source (origin) by clusturing random forest analysis performed on the core section of the otoliths only.