Abstract Along the Chilean coast, at least one type of orca ( Orcinus orca linnaeus , 1758) is documented for Patagonia throughout the subtropical North. Here, first land-based anecdotal observations (2014/2015) from Los Ríos Region, northwardly adjacent to the Subantarctic, were complemented by records from a casual citizen science network (2021–2023). The 32 sightings included in the analysis suggest that orcas stay for 1–4, possibly up to 12 days in regional waters, without apparent seasonal patterns. Observed groups consisted of 1–9 (mean: 4.03) individuals. As in northern Chile, predation on South American sea lions ( Otaria flavescens shaw , 1800) includes the facilitation of prey access through purse seiners, and hints on cultural transmission were found. Nonetheless, a larger prey spectrum is suggested, wherein pelagic/demersal species possibly play a role, whereas other cetaceans appear to represent at least no preferred prey. Play and/or training with a live seabird was recorded, but so far no predation on birds. The observations on diet, behavior, and sociobiology reveal similarities not only to orcas in northern through Patagonian Chile, but also to orcas in Argentinian Patagonia, and to Pacific orcas further north. These as well as differences found both within and beyond the region point to the need for intensified studies to examine orca types/type-relatedness, behavior, and ecology—foremost in light of conservation.
Niebaum et al. (2026) studied this question.