Hector’s and Māui dolphin deaths (1921–2015)

The Hector’s and Māui dolphins are subspecies of the small dolphin Cephalorhynchus hectori. These coastal dolphins are endemic to New Zealand (not found anywhere else). Māui dolphins are found on the west coast of the North Island, most often between Maunganui Bluff, north of Dargaville, and New Plymouth. Hector’s dolphins are mostly found around the South Island. Both subspecies are threatened with extinction. The Hector’s dolphin is classified as nationally endangered, while the Māui dolphin is nationally critical. Dolphins can become entangled in fishing gear used by both commercial and recreational fishers, with set nets posing a particularly high risk. Reporting the bycatch of protected species helps us understand the pressures our protected marine species face from fishing.
We report on two aspects of Hector’s and Māui dolphin deaths based on data extracted from the Department of Conservation (DOC) Incident Database for 1921–2015: the number of dolphin deaths by cause of death, including a comparison of deaths over 1996–2015; and the number of dolphin deaths from entanglement by type of fishing gear.