Abstract
The Sooty Shearwater (Ardenna grisea) is a species facing global decline, nesting on southern hemisphere islands, and migrating to the northern hemisphere during the non-breeding season. This study confirms the species ́ breeding presence on Isla de los Estados in the Fuegian archipelago, Argentina. Additionally, we present a preliminary evaluation of its habitat utilization. Active burrows were found along the northern coast of the island on slopes with dense, stumpy subantarctic forests and beneath or alongside rocky outcrops overlooking the coast. These discoveries provide valuable insights into the population status of the species, offering critical insights that can significantly inform and enhance conservation efforts.