Hector's Dolphin Cephalorhynchus hectori calf mortalities may indicate new risks from boat traffic and habituation

Abstract

Two Hector's Dolphin calves Cephalorhynchus hectori were killed by probable boat collision in 1999, indicating that boat strikes may pose more of a threat to the species than previously thought. When discovered, one dead calf was still tended by its mother. After recovery, both animals were necropsied with trauma from boat strikes as the most likely cause of death. These deaths are discussed in the context of increasing human contact with Hector's Dolphins in Akaroa Harbour, and risks to the dolphins caused by this habituation.