New measures to protect Maui's dolphins suggest the
Government is responding to international fears for the
diminutive dolphin found only in New Zealand waters. But is it
too little, too late? Geoff Cumming, of the NZ Herald
What is required to save the Maui's dolphin, or even if it
can be saved, is uncertain. Photo from NZ Herald.
If the world's most endangered dolphin has any awareness of
its plight, it would do well to make itself known to the
Taranaki fishing fleet right now.
Since July, the five set-net fishing boats out of New
Plymouth have been barred from fishing within two nautical
miles of shore, where the rig and blue warehou they target
are most abundant. To fish further out - between two and
seven nautical miles - they must have observers on board who
record in their log books every 15 minutes what they have
At the time of writing, they had covered 4540 nautical miles
during 168 days at sea both inside and outside the restricted
area - and the number of Maui's dolphin sightings remains a
big, fat zero.
But marine scientists want fishing restrictions extended even
further and Primary Industries Minister David Carter is about
to decide whether to retain the interim measures or to ban
gill-net fishing out to four nautical miles - arguably
triggering extinction for the region's fishing industry.
The options are outlined in a review of the Threat Management
Plan for Hector's and Maui's dolphins, for which consultation
closes on Monday.
If the fishermen are right and there are no Maui's dolphins
off Taranaki, what will the measures achieve?
It's not just a handful of fishermen, their crew and families
whose livelihoods are at stake. New Plymouth has two fish
processors employing a further 30 people. The impact of the
interim restrictions on catches has already forced one to lay
Their jobs might be a small price to pay for saving an
endemic (found only in New Zealand waters) dolphin, not least
in sparing the blow to our clean, green image that extinction
will bring. But if fishermen, marine scientists and
conservationists agree on one thing, it is that the latest
measures will not save the dolphins.
Most scientists on a risk assessment panel that informed the
review agreed the extent of the dolphins' range is Wanganui,
and wanted fishing restrictions extended that far south.
The Department of Conservation wanted the interim Taranaki
ban to go out to seven nautical miles, in line with
restrictions introduced in 2008 off Auckland and Waikato (as
far south as Pariokariwa Pt).
International agencies including the International Whaling
Commission support a ban on set nets and trawlers to the 100m
depth contour. But the Ministry of Primary Industries - in
charge of the fishing options in the review - gives Carter
the choice of sticking with the two nautical mile ban as far
south as Hawera or extending it to four nautical miles.
The fishermen say any restrictions are pointless south of
Pariokariwa Pt because the dolphins are not there. Keith
Mawson, of processor Egmont Seafoods, says for the past
decade targeting fishing has been a soft option rather than
funding research into the Maui's numbers, location and
"We should be able to fish our historical grounds until
there's evidence that there are Maui's dolphins in this area.
"There are guys who've been fishing for 35 or 40 years and
they've never seen one." But the industry's stance was not
helped in January, when fisherman Ian McDougall killed a
dolphin while gill-netting off Cape Egmont.
We will never know whether it was a Hector's or a Maui's - he
threw it overboard, fearing prosecution under the Wildlife
Act for having an endangered species in his possession. But
he reported the bycatch and MPI concluded it was most likely
Found only in New Zealand waters, the threatened Hector's
dolphin is the world's smallest, with its critically
endangered sub-species, the Maui's, growing to no more than
The Maui's evolution as a sub-species stems from its
isolation from South Island Hector's populations off
northwest Nelson, Banks Peninsula and the bottom of the South
They prefer coastal shallows, harbours and estuaries, finding
their way in turbid inshore waters using ultrasound, but they
have trouble picking up modern nylon gill nets.
Their plight was highlighted in the early 1990s when
University of Otago researchers Liz Slooten and Steve Dawson
found large numbers were dying in gill nets off Banks
Alarmingly, research estimates the adult Maui's population is
about 55, with fewer than 20 females of breeding age. This is
half the estimate from a previous survey.
The Doc-funded research by University of Auckland scientists
over consecutive summers also challenged assumptions that the
dolphins do not travel far, revealing one had moved 80km.
Then came confirmed sightings of Hector's dolphins in the
area - two live and two washed ashore. Their presence has
excited scientists by raising the prospect that the Hector's
could provide a lifeline for the Maui's through
Fishers say the Hector's are occasional strays and argue that
any interbreeding would result in a hybrid, not a Maui's.
Though genetic sampling has confirmed the Maui's were once as
far south as Kapiti and Wellington harbour, they are now
thought largely confined to the coast between the Kaipara and
Kawhia harbours and concentrated in a 40 nautical mile
stretch from Manukau Harbour to south of Port Waikato.
The Prime Minister's chief science adviser, Sir Peter
Gluckman, is one scientist who has publicly wondered whether
the dolphin is beyond the tipping point for species survival.
But cetacean experts on the risk assessment panel concluded
the Maui's was not beyond salvation, pointing to the recovery
of southern right whales and Antarctic blue whales from quite
low numbers once protections were in place.
"Saving Maui's is quite simple," Slooten says.
"It simply consists of stopping an impact. There is no need
to pour millions of dollars in. All we need to say is, if you
want to fish in a critically endangered habitat please use
Sightings of Hector's dolphins in the area have raised hopes.
Environmental groups and some scientists want a "protection
corridor" created between Taranaki and northwest Nelson to
increase the chances that Hector's dolphins may move north
"Fifty-five adults is really low," says Slooten.
"They don't stand much chance unless many animals come in
from the South Island.
It's better to have a slightly weakened Maui's dolphin gene
pool than to preside over the extinction of an entire
Other scientists agree interbreeding would not erase the
genetic differences that make the Maui's distinct. In fact,
increased genetic diversity is what the tiny population
Dr Slooten says there is not time to obtain the level of
proof needed to quieten the fishermen.
"We've got to make a precautionary decision and this seems to
be lost on MPI." However, New Zealand was the only country to
oppose an International Union for the Conservation of Nature
resolution calling for gill nets and trawling to be banned to
the 100m depth contour in areas of Maui's and Hector's
Doc representatives at the meeting bowed to Ministry of
Primary Industries advice that such an extension lacked
MPI is in charge of the fisheries recommendations for the
Latest research has thrown a new element into the mix.
Massey University pathobiologist Dr Wendi Roe has established
a parasite traced to cats as the prime cause of death in
seven of 28 beached Hector's-type dolphins she autopsied,
including two out of three Maui's dolphins.
The fishing industry has seized on the findings to back its
argument that, instead of targeting fishing, urgent research
is needed into the range, health and abundance of the
dolphins so steps can be taken to rebuild the population.