Osteo-pathological analysis provides evidence for a survived historical ship strike in a Southern Hemisphere fin whale (Balaenoptera physalus)

Abstract

The life history of a fin whale (Balaenoptera physalus) caught during whaling operations in the 1950s was partly reconstructed. 3D surface models of the bones of the skeleton curated at the Zoological Museum of Hamburg were used for an osteopathological analysis. The skeleton revealed multiple healed fractures of ribs and a scapula. Moreover, the processus spinosi of several vertebrae were deformed and arthrosis was found. Together, the pathological findings provide evidence for large blunt trauma and secondary effects arising from it. Reconstruction of the likely cause of events suggests collision with a ship inflicting the fractures and leading to post traumatic posture damage as indicated by skeletal deformations. The injured bones had fully healed before the fin whale was killed by a whaler in the South Atlantic in 1952. This study is the first in-detail reconstruction of a historical whale—ship collision in the Southern Hemisphere, dating back to the 1940s, and the first documentation of a healed scapula fracture in a fin whale. The skeleton provides evidence for survival of a ship strike by a fin whale with severe injuries causing long-term impairment.

Report of the Scientific Committee

“…It was noted that, while ship strikes are often assessed from a conservation perspective, there are clear implications for the health and welfare of struck but surviving cetaceans, and that welfare considerations often provide the motivation for stakeholders to implement mitigation measures. Daume et al (2023) describe an osteopathological analysis of the skeleton of a fin whale that revealed multiple healed fractures of ribs and a scapula. Reconstruction of the likely cause of events suggests collision with a ship, inflicting the fractures and leading to post-traumatic posture damage.…”