Make your own free website on
New Zealand Whale and Dolphin Trust logo
What's New?
Our Research
Who's Involved
What You Can Do
Contact Details
What's New?/NI Hector's Dolphin last updated 08 June 2005
North Island Hector's Dolphin - help protect this critically endangered population
hector's dolphin jumping
First, some good news...

There is a protected area for the North Island Hector's dolphin, also known as Maui's dolphin, that extends four nautical miles off the coast, from Maunganui Bluff (north of Dargaville) to Pariokariwa Point (north of New Plymouth). The protected area encompasses some 400km of coastline. This is major progress. To see how this decision was reached, read on...


Hector's dolphin is an endangered species, only found in New Zealand. The North Island population is very small (just over 100 individuals, Slooten et al., 2004, 2005) and has recently been listed as critically endangered on the international Red List of threatened species (IUCN, 2000). North Island and South Island Hector's dolphins are genetically different (Pichler et al., 1998).

The North Island population (like several other Hector's dolphin populations) is declining (Martien et al., 1999; Pichler and Baker, 2000), due to bycatch in gillnets (Martien et al., 1999). A sustainable level of bycatch would be about one dolphin every 5 years. A meeting of fishers, conservation groups, scientists and government officials (in Wellington, May 2000) agreed that bycatch should be reduced to zero, to allow the population to recover. The only effective way to achieve this would be to avoid overlap between dolphins and gillnets. In addition, it will be important to keep a close eye on other human activities in the area. For example, recent proposals to carry out sand mining throughout the range of North Island Hector's dolphins is not good news.

North Island Hector's dolphins are found between Maunganui Bluff (north of Dargaville) and New Plymouth. To reduce bycatch of Hector's dolphins to sustainable levels, it would be necessary to avoid gillnetting and trawling for this whole area, out to at least four nautical miles offshore.


Will this be sufficient?

There are still concerns about the following issues in particular:

  • The current protected area does not include the harbours on the North Island west coast
  • It does not include restrictions on trawling
  • There are no restrictions on other activities like sand mining
Hector's dolphins have been sighted in the harbours on the North Island west coast, and further research is planned to find out how much time they spend in these harbours. While not as much of a risk as gillnetting, Hector's dolphins are regularly caught in trawl fisheries. Recent population modelling by a group of scientists led by the Ministry of Fisheries suggests that current protection may not be sufficient to prevent further population decline.
Why was the North Island Hector's dolphin sanctuary necessary?
It seems that the majority of New Zealanders are very concerned about Hector's dolphin conservation, but opinions certainly range the whole spectrum from "let's do something right now!" through to "why should I care?". So, why should we care...
Hector's dolphins are only found in New Zealand
The species is listed as endangered, and the North Island population as critically endangered, on the international Red List of Endangered Species. This is an international recognition that impacts on the species are not sustainable, and the species will go extinct unless we act. Or, rather unless we stop acting...
This is our fault
We are the reason that Hector's dolphins are threatened with extinction. New Zealanders are threatening the existence of Hector's dolphins by catching them in fishing gear, polluting their environment and killing dolphins by running over them in boats.
The main threat is gillnet entanglement
Hector's dolphins are caught in trawls and gillnets. The risk of entanglement in gillnets, per day fishing, is far greater for gillnetting. Gillnet fishing, on its own, is sufficient to cause populations around NZ to decline and ultimately to go extinct.
This threat is totally and easily avoidable
Every single fish species that is caught in commercial and recreational gillnetting can be caught using other fishing methods. We could stop killing Hector's dolphins in gillnets (and trawls if we wanted to) tomorrow. This is not like some pollution event that has already occurred and we are powerless to prevent the pollution getting to Hector's dolphins. Gillnetting is something we do, voluntarily, and we could stop doing.
The issue is not jobs or money

Very few commercial fishers use gillnets. In terms of total profits from fishing, gillnetting barely registers. None of the major income earners (e.g. orange roughy, squid, hoki) are caught using gillnets. Most of the fish caught in gillnets is of poor quality and low value, and is used in the local fish and chip trade. The trade-off on the North Island west coast is whether the extinction of the North Island Hector's dolphin is justified to avoid a slight decrease in profitability for about five commercial fishers.

Fishers currently using gillnets could easily switch to other fishing gear. No jobs would need to be lost. The problem is that some in the fishing industry see this issue as setting a dangerous precedent. If they give in and change to more selective fishing gear, this could set a precedent for having to make changes to other unsustainable fishing practices. This could have serious implications for the fishing industry. A sustainable fishing industry would certainly be less profitable.

So, what can I do to help save the North Island Hector's dolphin?

Write to the Minister of Fisheries and the Minister of Conservation!

The marine mammal sanctuary goes some way to helping this species, but not far enough. Several meetings of interested groups (Fishers, Ministry of Fisheries, Department of Conservation, scientists, conservation groups, etc.) have agreed that the management goal for North Island Hector's dolphin should be to reduce human impacts to as close to zero as possible. Extending the sanctuary to include harbours (Kaipara, Manukau, Kawhia, Raglan, Aotea and Port Waikato) and having restrictions on trawling will give the North Island Hector's dolphin a much greater chance of survival.

Please write a letter or send an e-mail supporting these, or stronger measures. Feel free to use any of the arguments above and the references below to support your case.

You can send your letter to:

  • David Benson-Pope, Minister of Fisheries, Parliament Buildings, Wellington
  • Chris Carter, Minister of Conservation, Parliament Buildings, Wellington
    (no stamp required)
Or by e-mail to:
  • Dawson, S., Pichler, F., Slooten, E., Russell, K. and Baker, C.S. 2001. North Island Hector's dolphin is vulnerable to extinction. Marine Mammal Science 17 (2): 366-371.
  • Dawson, S.M., Read, A. and Slooten, E. 1998. Pingers, porpoises and power: Uncertainties with using pingers to reduce bycatch of small cetaceans. Biological Conservation 84(2): 141-146.
  • IUCN Red Data List 2000. IUCN, World Conservation Union, Gland, Switzerland,
  • Martien, K.K., Taylor, B.L., Slooten, E. Dawson, S.M. 1999. A sensitivity analysis to guide research and management for Hector's dolphin. Biological Conservation 90: 183-191.
  • Pichler, F. and Baker, CS 2000. Loss of genetic diversity in the endemic Hector's dolphin due to fisheries-related mortality. Proc R. Soc. Lond. B. 267:97-102.
  • Pichler, F., Baker, CS, Dawson, S.M. & Slooten, E. 1998. Mitochondrial differences between east and west coast populations of Hector's dolphin. Conservation Biology. 12(3): 1-8.
  • Russell, K. 1999. The North Island Hector's dolphin: a species in need of conservation. Unpub. MSc thesis,
  • Slooten, E., Dawson, S., Rayment, W.J. and Childerhouse, S.J. 2004. Aerial survey of North Island Hector's dolphin. Final report to Department of Conservation and World Wide Fund for Nature, Wellington.
  • Slooten, E., Dawson, S., Rayment, W.J. and Childerhouse, S.J. 2005. Distribution of Maui's dolphin, Cephalorhynchus hectori maui. New Zealand Fisheries Assessment Report, Published by Ministry of Fisheries, Wellington.
  • University of Auckland.
copyright information