Veronica Rotman is calling for cameras on commercial fishing boats, much greater observer coverage, investment in dolphin-friendly fishing methods to protect the Maui's and Hector dolphin. Photo: Getty Images

A series of full page Seafood NZ advertisements in the Dominion Post suggests the industry is throwing its weight behind a ‘lip service’ campaign to reassure the public it’s a sustainable industry.

Claims that “most (dolphins) feed around river mouths in the protected area”, and the existing sanctuary is the “heart of the Māui habitat” are vague and misleading. The Māui dolphin habitat is largely inaccessible, along rough coastline where boat surveys are near impossible for most of the year and research is limited to summer months. This means there isn’t enough information to fully support Seafood NZ’s self-serving claims.

We do know Māui dolphins come inshore during the summer months but acoustic surveys suggest they travel offshore during winter, likely outside the current protection area. This means they need better protection, and we need improved understanding of their movements, to prevent them joining the list of New Zealand’s extinct species. We challenge Seafood NZ to support these research efforts via new technologies such as drones, artificial intelligence, thermal imaging and acoustic monitoring.

So back to the advertisements – and one which states: the “Last confirmed death of a Māui dolphin by commercial fishing happened 17 years ago”. This is misleading.

Bycatch data sourced from “Dragonfly Data Science” indicated zero observed bycatch associated with set net or trawl commercial fisheries between 2003 and 2017.  Set net commercial fisheries on the West coast of the North Island averaged observer coverage of less than one percent, while trawls were between four and 55 percent during this time period.

It is suggested set nets attribute 84 percent of fisheries risk to Māui dolphins. However, Department of Conservation statistics from 2019 confirm trawls had far greater coverage of observers. It would be more accurate if Seafood NZ said the last confirmed death willingly recorded by the commercial fishing industry happened 17 years ago.

DOC’s Māui dolphin incident database displays the death of a Māui dolphin in 2012 with cause of death as “known bycatch in commercial set net”. This is well within the previous 17 year time period and was reported by a commercial fisherman. However, because the dolphin was not brought ashore, a necroscopy was not performed and Seafood NZ claims the dolphin ‘was not identified as a Māui’. Very fishy indeed.

The incident database states that it relies on reports from fishing vessels, as well as public sightings of dead dolphins, and is biased towards areas with high visitor numbers. In many cases, dolphin carcasses in this DOC database have been found decomposed beyond possibility of a necroscopy and therefore no cause of death determined.

The 2012 Māui Dolphin Threat Management Plan states that bycatch is likely under-reported. The Ministry for Primary Industries suggests incidental capture information available on the DOC database does not represent the magnitude of fisheries capture for reasons including under-reporting, carcasses not washing ashore, or lack of evidence that fishing gear was the cause of death.

International Whaling Commission representative and prominent dolphin researcher, Elisabeth Slooten, suggests not all dolphins caught in set nets show symptoms of capture. Trawl deaths are even more difficult to distinguish. The recent 2019 Threat Management Plan Risk Assessment estimates commercial fishing currently accounts for one Māui dolphin death every nine years. Although fishermen are compelled by law to report entanglements, there is no incentive to do so.

Trawl commercial fisheries are known to kill Hector’s dolphins, however there are no records of Māui dolphins being caught. Bycatch of other cetacean species such as Common dolphins have been reported by trawls off the west coast of the North Island which indicates the threat to Māui dolphins is significant. We will only get a full extent of risk and mortality rate of Māui dolphins if observer coverage is greatly improved.

The New Zealand Marine Mammals Act (1978) clearly states bycatch mortality rates must be managed to ensure threatened species achieve non-threatened status as soon as practicable, not exceeding a period of 20 years. This is not possible with existing protection measures.

Although a small portion of Māui dolphin range is protected, there is still considerable overlap between their habitat and commercial set net and trawl fisheries. Considering their conservation status is ‘nationally critical’ and population has depleted to approximately 63 individuals, any bycatch is unsustainable and unacceptable.

The International Whaling Commission encourages full protection from set net and trawl commercial fishing for both Māui and Hector’s dolphins in the entirety of its range, out to the 100 metre depth contour. This would provide the best chance of population recovery, and Our Seas Our Future urges extended protection until definitive information on dolphin distribution has been acquired.

If Seafood NZ cannot “countenance the obliteration of small fishing companies”, they must support their transition to sustainable dolphin-safe fishing methods in the region, such as hook and line techniques and fish-traps. A recent report by Fisheries New Zealand estimated a financial loss of between $20.9 million and $143.5 million over five years depending on area of fishery closed. Market Economics’ associate director Rodney Yeoman suggested these figures to be 10 times overestimated in Newsroom in July. Does anyone smell a red herring?

Maui dolphins provide ecosystem value, and cultural and economic value, being the smallest and rarest marine dolphin in the world. Actions put in place now must reflect the values of Aotearoa, and not solely those of the fishing industry.

OSOF founder Noel Jhinku says: “We need cameras on boats, much greater observer coverage, investment in dolphin-friendly fishing methods, more research to better understand populations and use of cutting-edge monitoring technology. Only then will we have a chance to prevent human-caused extinction of our endemic Māui and Hector’s dolphins.”

Veronica is science advisor to Our Seas Our Future (OSOF), a voluntary organisation which aims to protect New Zealand’s coastal and marine ecosystems. 

Veronica Rotman is studying for an MSc in Marine Science at the University of Auckland.

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