First confirmed stranding of a fin whale (Balaenoptera physalus) in Tierra del Fuego, Argentina

Fin whales (Balaenoptera physalus) can be found worldwide, in oceanic waters, though are rarely found in coastal areas of wide and shallow continental platforms such as those in the western South Atlantic Ocean. Here we report the first confirmed stranding of a B. physalus off the Atlantic coast of Tierra del Fuego (TDF), in July (austral winter) of 2016. In addition, a bibliographic review of the strandings of this species was carried out on the Argentinian coasts and especially on TDF. The animal was fresh when it was found and may have been alive at the moment of the stranding. The specimen was a physically immature female with a total length 15.8 m. No injuries or fishing gear were observed to suggest accidental entanglement or vessel collision. The specimen's stomachs were empty except for a low-grade infestation with the trematode Ogmogaster antarcticus, but without any associated macroscopic gastric pathology. Although the necropsy was carried out within a few hours of death, we could not make an accurate diagnosis of the cause of death. However, the insufficient fat deposits indicate a bad physical condition and may have contributed to its stranding and subsequent death. This specimen represents the first confirmed stranding of this species in TDF.

Automated summary

Fin whales are globally distributed in oceanic waters but rarely found in coastal areas with wide and shallow continental platforms like the western South Atlantic Ocean. The first confirmed stranding of a B. physalus off the Atlantic coast of Tierra del Fuego was reported in July 2016. The physically immature female specimen was found fresh with minimal injuries or signs of entanglement, yet the cause of death could not be accurately determined despite the necropsy findings. Insufficient fat deposits were noted, indicating poor physical condition which may have led to the stranding and subsequent death.