Help Shape Threat Management Plan for New Zealand’s Endemic Maui Dolphin

Wednesday, 31 Oct, 2012

Scientific research confirms human impact responsible for 94% species loss rate.

Photo courtesy of Steve Dawson

New Zealand’s Ministry of Primary Industries (MPI) and Department of Conservation (DOC) are now receiving public submissions for the Threat Management Plan (TMP) for New Zealand’s endemic Maui dolphin. The MPI will consider all submissions which will then be analysed and recommendations developed for the Minister of Primary Industries to decide upon protection measures. This is a separate request for submissions apart from those made earlier this year. The next review will be in 2017. The population over one year of age is reported to be 55 – 79 and approximately 20-25 breeding females are currently remaining. There has been a staggering species loss rate of 94% from population estimates taken 1970.

The Maui dolphin, Cephalorynchus hectori maui, lives only on the west coast of New Zealand’s North Island and is a sub-species of the Hector’s Dolphin Cephaloryhnchus hectori hectori which is found in the South Island. Although visually similar, scientific research determined the Maui’s as a sub-species in 2002, due to differences in geography and mitochondria.

In the wild, these dolphins live up to 22 years of age and in an optimal environment they will begin breeding at approximately 7 years of age, birthing one calf every 2 – 6 years. The Maui dolphin habitat is in the coastal environs, up to the 100m depth contour, although they travel further offshore during winter feeding throughout the water column. Within their coastal habitat range, sight and sound recorded research has proved a presence in the Kaipara and Manukau Harbours.

The decline of this species has been documented by various universities, government departments, and ministries, with human-induced impacts agreed as the major cause. The TMP review considers that fishing related activities such as entanglement in nylon filament set nets and trawling account for 95% of mortalities, with the remaining 5% due to seismic surveying, mining, pollution, and disease. The review estimates a 95.7% likelihood of further decline over the next five years at a rate of 7.6% each year. The Maui dolphin population is estimated to be able to sustain one death per 10 -23 years due to human related activities, five were lost in the past year.

The International Union for the Conservation for Nature (IUCN) lists the Maui dolphin as Critically Endangered and facing a high risk of extinction. New Zealand lists the Maui dolphin as conservation dependent. Earlier this year a public submission phase to offer better protection for the Maui dolphin resulted in a temporary set-net ban south of New Plymouth, an inadequate measure covering a small area.

In July the International Whaling Commission Scientific Committee urged New Zealand to take immediate action to effectively prevent an imminent extinction. In September, 576 members of the IUCN World Conservation Congress voted overwhelmingly to a motion to stop the extinction of the world’s rarest dolphin- Maui dolphin. There were two votes against the motion – New Zealand’s.

Scientific research has determined both cause and effect of the declining Maui dolphin population, and marine mammal sanctuaries have been proven in the New Zealand context to assist with species recovery. The purpose of the TMP is to identify current threats and to implement strategies that will reduce the human-induced impacts upon the Maui dolphin. We are watching and documenting the extinction of the Maui dolphin. Make sure you are one of the many who act to stop it.

Please send submissions to

Please mention the following precautionary measures in your submission:

Fishing-related measures proposed by the MPI:

  • Ban set nets and trawling up to the 100m depth contour of the total habitat range
  • Full protection in the Kaipara and Manukau Harbours
  • Protection between the North and South Island

Non-fishing related measures proposed by DOC:

  • Extend West Coast North Island Marine Mammal Sanctuaries
  • Extend restrictions of Seismic Surveying in Marine Mammal Sanctuaries
  • Extend restrictions of sea bed mining

And yes, please sign the petition at


Photo courtesy of Steve Dawson
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