Maui's Dolphin (North Island Hector's Dolphin) Cephalorhynchus hectori maui
Maui's dolphins (popoto) are the world’s rarest marine dolphins, found only in waters around New Zealand. They are most easily recognized by their round dorsal fin.
Research has found that the Maui dolphin is a sub-species of Hector's dolphin and is genetically distinct from the South Island Hector's dolphin.
Maui's dolphin is ‘Critically Endangered’ (World Conservation Union - www.redlist.org), with an estimated population of only about 111 individuals.
Any species that has declined to such a small number is at great risk, but Maui's dolphins are in an even worse situation because their population may include fewer than 60 mature animals with only around 25 breeding females. Genetic diversity is thought to be very low, increasing its vulnerability to environmental changes and population decline.
Maui’s dolphins are literally on the brink of extinction!
Population Decline
In the nineteenth century Maui's dolphins were spread around the North Island coastline, from Tuaroa Point in Northland to mid-Bay of Plenty (yellow).
In the 1970s the majority of strandings (the main indicator of historical distribution) were around the lower North Taranaki Bight. Decline in reported deaths in this area illustrate the rapid shrinkage of their distribution (see graph).
The Maui’s dolphins distribution has shrunk in recent years. Maui’s dolphins are now only found from Maunganui Bluff (near Dargaville) to just south of New Plymouth. Research in 2005 showed that the highest densities are between Manukau Harbour and Port Waikato.
Human caused deaths must be zero to allow Maui's dolphins to survive and recover.
What are the threats and what is being done?
Hector’s dolphins prefer shallow (less than 100m) waters, which brings them into direct contact with humans. This creates many threats, the single biggest threat being from set nets.
Set net ban
In August 2001, after lobbying from Forest & Bird and other groups, the Minister of Fisheries made a decision to ban all set netting from Maunganui Bluff to Pariokariwa Point. This ban was appealed through the courts by commercial fishers, and the ban and trawling controls were lifted (a ban remained on recreational set netting).
The ban was appealed, during which time at least 3 more Maui’s dolphins washed up dead on beaches - and more were likely to have drowned and not washed up.
The Ministry of Fisheries initiated a new consultation process in April 2002. After extensive discussions with stakeholders the Minister decided in favour of the ban on commercial set netting in January 2003.
The ban prohibits the use of commercial and recreational set nets within four nautical miles of the coast from Maunganui Bluff (north of Dargaville) to Pariokariwa Point (north of New Plymouth). In addition, all set netting is banned in the Manukau Harbour entrance west of Puponga Point (Cornwallis) to a point 0.5nm north of Kauri Point (eastern end of Big Bay), and then to Kauri Point.
Since the ban has been in place, there have been no reported Maui dolphin deaths confirmed caused by set nets.
Although a very positive step forward, the ban only partially protects Maui's dolphins.
Most of the Maui's dolphins range, particularly offshore, is unprotected. Also, none of the inner harbours are included in this ban. Maui’s dolphins have been sighted in three out of five of these harbours. Detailed studies have been carried out only in the Manukau Harbour and confirm that Maui’s dolphins regularly use the harbour and range further into the harbour than the protected area.
Maui's dolphins sighted south of the regulated zone, are also not being adequately addressed.
An immediate set net ban over their entire range is crucial in helping Maui's dolphin survival.
Trawling and Danish seining ban
Trawling and Danish seigning also pose significant threats to Maui’s dolphins. Of particular concern is trawling by the West Coast snapper fishery. Both fishing methods are banned in defined areas including: Kawhia Harbour, Aotea Harbour, Raglan Harbour, Manukau Harbour, Kaipara Harbour, Hokianga Harbour, Waikato River Mouth and the harbours of Herekino and Whangape. There is also a voluntary trawl agreement in place that requires vessels to not trawl within 1 nautical mile from shore.
These closures were not necessarily put in place for the purpose of protecting Maui’s dolphins, nevertheless they do offer some protection, but not to all dolphins throughout their range.
One of the key problems with this threat is that there is minimal observer coverage and so little known about if and how many Maui’s are being caught and not reported.
The critically endangered Maui's dolphin cannot withstand any fishing deaths if it is to survive and recover to a safe population size.
Other threats
Other human-induced threats –boat strikes, tourism, marine farming, pollution, sand mining and construction.
Forest & Bird is proposing the protection of Maui’s dolphins with a Marine Mammal Sanctuary covering their entire range: from Maunganui Bluff to Cape Egmont, in all waters less than 100m deep.
Click here for a copy of the Forest & Bird proposal for a Marine Mammal Sanctuary to protect Maui's dolphins.(PDF)
Under the proposed marine mammal sanctuary, Forest & Bird is seeking the following restrictions:
A ban on set nets and drift nets
Trawling banned within four nautical miles of the coast; all vessels to have vessel monitoring systems, observers or by-catch monitoring equipment on board
Boats to adhere to existing speed limits within 300 metres of Maui’s dolphins
No marine mining, littering, waste discharge, pollution.
Forest & Bird has received public feedback on the marine mammal sanctuary proposal. Click here for our Consultation Report. (PDF) We continue to work with government agencies, community groups, fishers and iwi to develop the proposal..
Long-term solutions
An education and enforcement regime to ensure compliance with Marine Mammal Sanctuary regulations is essential for long-term protection of Maui’s dolphins. Once effectively implemented, a sanctuary should take away the focus on fishing related threats and allow for broader management of other threats and protection of the west coast marine environment.
The only viable solutions to provide long-term protection of Hector’s dolphins as a species, are to implement:
a national set net banand
Marine Mammal Sanctuaries around each of the critical areas.
Email or write to your local MP and ask them to support the call for the above mentioned solutions
If you are lucky enough to see a Maui's dolphin please report your sighting. Call 0800 4 MAUIS (462 847) or contact the Department of Conservation's marine mammal researcher Kirsty Russell at krussell@doc.govt.nz
Download our Disappearing Hector's Dolphin Desktop Image - Don't let this be the last time you see them! Click here for JPEG
More information on this
site
Forest & Bird proposal for a Marine Mammal Sanctuary to protect Maui's dolphins Click for PDF
Forest & Bird Marine Mammal Sanctuary proposal consultation report Click for PDF
Maui's Dolphins - Emergency 111: Feature article by Helen Bain, Communications Officer Click for PDF
Maui's Dolphins - Frequently Asked Questions Click for PDF
Leaping Hector's photograph by Steve Dawson/NZ Whale & Dolphin Trust; Hector's in net photograph by Department of Conservation; Maui & calf by Silvia Scali
Immediate solutions: Maui Marine Mammal Sanctuary 
