World’s rarest dolphin faces extinction

By Tracy Brighten

Will the New Zealand government protect the last 50 Maui dolphins from fishing and oil industry threats?

Science Nutshell Single Maui dolphin by Will Rayment

Experts presented new research on the critically endangered Maui’s dolphin that sends a clear message to the New Zealand government: act now or be responsible for following in China’s footsteps after the extinction of the Yangtze River dolphin in 2006.

In May, the International Whaling Commission Scientific Committee held its annual meeting in San Diego, U.S, where 200 of the world’s leading scientists presented their latest cetacean research.

In 2014, Otago University professors Dr Liz Slooten and Dr Steve Dawson, the world’s leading New Zealand dolphin experts, estimated the Maui’s dolphin population at 55 adults over one year old.

Slooten and Dr Barbara Maas, NABU International’s Head of Endangered Species Conservation, presented revised population calculations showing 43-47 dolphins and only 10-12 breeding females. They predict functional extinction of the Maui’s dolphin within 15 years unless protection measures are increased.

Found only in the coastal waters of the North Island’s west coast, the Maui’s dolphin with distinct rounded dorsal fin is a subspecies of Hector’s dolphin that inhabits the South Island. At only 1.6 m long, the Maui’s is not only the world’s rarest dolphin, it is also the smallest.

According to the 2012 Maui’s Dolphin Threat Assessment, a joint Department of Conservation and Ministry of Primary Industries report, fishing-related activities are responsible for 95.5% of human-related Maui’s dolphin mortalities.

The population can sustain one death in 10-23 years, yet the estimated death rate from bycatch alone is 3-4 per year. Considering Maui’s and Hector’s biology – a female does not reach reproductive maturity until 7-9 years old, giving birth to one calf every 2-4 years – the loss of a female significantly impacts species survival.

Gillnets pose the biggest threat. The mesh of nylon gillnetting is so fine it is almost invisible, and dolphins become entangled. Interviewed by journalist Zoe Helene, Slooten describes what happens.

“A dolphin caught in a net struggles madly to try to escape. At the end of this struggle, the dolphin suffocates. It would take up to five minutes or so to die.”

Like humans, dolphins are social mammals. Slooten recalls, “We’ve seen one dolphin that had died in a gillnet that was covered in fresh toothrakes, many of which were bleeding. It seems that the other dolphins in the group tried to get this dolphin out of the net and failed.”

While acknowledging that the Maui’s Dolphin Threat Management Plan revision in 2013 provides some extra protection from set nets, Forest & Bird Advocacy Manager Kevin Hackwell wants more. “The set net ban needs to be extended to all regions where these nationally-critical Maui’s dolphins are found. That includes all harbours and offshore to the 100m depth contour.”

Domestic resistance is strong. New Zealand’s fifth largest export earner, the seafood industry is a dominant player in the conservation game. They argue that fishing has a temporary impact on the environment, unlike farming’s permanent impact. But extinction is permanent and dolphin numbers are decreasing as the debate continues.

When asked about Maui’s extinction during the last election campaign, the New Zealand Primary Industries Minister was clear. “Our position is that if there are sightings beyond the protected area then we will review the boundaries, but in 900 fishing trips, there have been no observations of Maui’s dolphins in these areas.”

Yet the chance of seeing Maui’s dolphins diminishes while the entirety of their habitat remains unprotected. While the observer program on commercial fishing boats leaving Taranaki on the west coast is well-intentioned, watching murky coastal waters for tiny dolphins must surely require uninterrupted concentration and 20/20 vision.

Dr Maas criticises economic-driven decisions on protection zones that “reflect fishing interests rather than match Maui’s dolphin distribution.”

Other threats include oil and gas exploration, mining, pollution, boat strikes, and disease. Austrian oil company OMV’s recent oil spill close to Maui’s habitat shows the danger posed by oil drilling in marine sensitive areas. Maas criticises the NZ government for granting oil drilling permits without fully considering scientific studies on the effects on the marine environment.

The campaign to save the critically endangered Maui’s has escalated into an international affair and is gaining global support.

At the International Whaling Commission meeting last September, 26 countries voted for total protection of Maui’s dolphins from fishing-related threats. Slooten and Maas seek a solution that satisfies both environmental and economic interests and will be looking for continued IWC support to save the Maui’s dolphin from extinction.

If the NZ government is to fend off international accusations of a “greenwash”, it needs to deliver on the tourist industry’s 100% Pure New Zealand image. If calls for increased dolphin protection zones and sustainable fishing methods continue to be ignored, the price to pay for eating fish caught by gillnets and trawling could be very high indeed.

Image credit: Maui dolphin by WWF/ Will Rayment.

Post updated in December 2015. First published on The News Hub on May 28, 2015


© All posts are protected by copyright with all rights reserved. You are very welcome to link to an article, but if you would like to re-publish my work, commercially or non-commercially, please contact me. Thank you.

About Tracy Brighten

With her passion for nature, health, education, and sustainability, Tracy writes creative content that connects with readers. She helps tell people's stories, build brands, and grow businesses. Thrives on words, birds and enthusiasm. For hire at www.tracybrightenwriter.com.

Leave a Reply

Your email address will not be published. Required fields are marked *