(…) Little is known regarding other causes of mortality and population trends of harbor porpoises from the Estuary and Gulf of St. Lawrence. Harbor porpoises have been reported to be occasional victims of attacks from bottlenose dolphins (Tursiops truncatus) in Great Britain and California, and from Pacific white-sided dolphins (L. obliquidens) in Washington State (Ross & Wilson, 1996; Baird, 1998; Cotter et al., 2011). Such interspecific violent interactions have never been reported from the Estuary and Gulf of St. Lawrence.
The objective of this communication is to describe the postmortem findings on a harbor porpoise calf presenting lesions suggestive of interspecific violent interactions with Atlantic white-sided dolphins. (…)