Cetaceans are known to play an important role in ecosystem structure and dynamics because they occupy the highest position in food webs. In order to improve our knowledge on the feeding ecology of the long finned pilot whale, Globicephala melas edwardii, in the western South Atlantic Ocean, we analyzed carbon (δ¹³C) and nitrogen (δ¹⁵N) stable isotope composition of bone collagen from 54 specimens found stranded along the coast of Tierra del Fuego, Argentina. Through Bayesian mixing models we estimated the contribution of the most putative prey to the consumer’s diet. Prey species were selected, based on previous knowledge and covered all possible foraging areas for the region that were analyzed through a visual spatial analysis (based on sightings records). Based on our results, the long finned pilot whale is mainly a teutophagous species, feeding on squids, and can complement its diet with neritic prey when moving sporadically to coastal areas. We found that the southeastern part of Tierra del Fuego, north of Staten Island and the slope break around the Burdwood Bank are plausible feeding areas, which offer suitable habitats where pilot whales can search for their preferred prey. These areas are important for Argentin’s conservation policies, since they enclose three oceanic Marine Protected Areas (Namuncurá–Burdwood Bank, Burdwood Bank II and Yaganes). Therefore, it is crucial to improve the knowledge regarding their foraging preferences in order to provide support for conservation and management strategies in these MPAs.

众所周知，鲸类在生态系统结构和动态中发挥着重要作用，因为它们在食物网中占据最高位置。为了提高我们对南大西洋西部长鳍领航鲸Globicephala melas edwardii摄食生态的了解，我们分析了碳 ( δ ¹³ C) 和氮 ( δ ¹⁵N) 来自阿根廷火地岛海岸搁浅的 54 个标本的骨胶原的稳定同位素组成。通过贝叶斯混合模型，我们估计了最可能的猎物对消费者饮食的贡献。根据先前的知识选择了猎物物种，并覆盖了该地区所有可能的觅食区域，这些区域通过视觉空间分析（基于目击记录）进行了分析。根据我们的研究结果，长鳍领航鲸主要是一种以鱿鱼为食的条食性物种，并且在零星移动到沿海地区时可以用浅海猎物补充其饮食。我们发现火地岛东南部、史坦顿岛以北和伯德伍德河岸周围的斜坡断裂是合理的觅食区，它提供了合适的栖息地，领航鲸可以在那里寻找他们喜欢的猎物。这些区域对阿根廷的保护政策很重要，因为它们包围了三个海洋海洋保护区（Namuncurá-Burdwood Bank、Burdwood Bank II 和 Yaganes）。因此，提高有关其觅食偏好的知识以支持这些海洋保护区的保护和管理战略至关重要。