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Rare black mudfish return home


A colony of one of New Zealand’s rarest freshwater fish has been released into a new habitat near Rangiriri, in the Waikato.

The large population of black mudfish were discovered by ecologists during environmental investigations carried out before construction of the Rangiriri section of the Waikato Expressway began.

The mudfish were caught and moved to specialised tanks at the University of Waikato, where they have been cared for by an expert team – until today, when they were released into their new, purpose built home.

Local tangata whenua, students from Rangiriri School and other invited guests, joined representatives from the NZ Transport Agency, Fletchers Construction and Kessels Ecology for the release, at 10.30am.

The fish were blessed by Tainui iwi, before being released into their new habitat by Kessels Ecology staff, who will monitor them for the next three years. 

The Transport Agency’s Waikato highway manager, Kaye Clark, said the new habitat, built by Fletcher Construction as part of the Rangiriri section of the Waikato Expressway, incorporated the colony’s initial home, with many improvements.

“These black mudfish are a vital part of the wetland food chain and ecosystem and they are at risk of extinction due to habitat loss, which is why it was vital we got their new home just right,” she said.

“The new habitat includes native plants and a winding stream channel, surrounded by shallower wetland areas.

“It is more than double the size of the area they were first discovered in and has been designed to exclude predators such as eels. There is also a system in place to adjust the water level if necessary.”

Waikato-Tainui chief executive, Parekawhia McLean, said the protection and restoration of native fisheries was important to Waikato-Tainui and was promoted through the iwi Environmental Plan and partnership with the NZ Transport Agency.

“Having our local marae and school children involved in today's release, will ensure the ongoing support for our native fisheries into the future,” he said.

Fletcher Construction project manager, Charles Stokes, said building the habitat had allowed his team to showcase their creative talents.

“The design for this habitat was relatively open with only criteria for water depth, area and planting which has allowed us to think outside the square and come up with something we believe will allow the population to flourish,” he said.

The mudfish remained a key focus as construction of the Rangiriri section started, Mr Stokes said,  with key projects planned to lessen the duration that the mudfish were relocated for.

“It has been an exciting process and it is great to see the mudfish return home.”

Kessels Ecology senior freshwater ecologist, Dr Jennifer Price, said the mudfish were at risk of extinction and it was great that the Transport Agency was doing everything possible to preserve their habitat.

“Black mudfish are only found in New Zealand and they are an important part of our unique indigenous biodiversity, just like kiwis but not quite as cuddly,” she said.

“They are at risk of extinction, and once they go extinct, we will lose them forever so it is great that the NZ Transport Agency are doing everything possible to preserve their habitat here in the Waikato.”

For more information about the Waikato Expressway go to: link)

 Adult mudfish
Adult mudfish.

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Rangiriri School students check out the mudfish before their release.

Ecologists release the  mudfish into their new home.


Editor’s note: The $4.8million Rangiriri section of the Waikato Expressway is currently under construction and is expected to open in late 2016. Extensive earthworks are scheduled to start later this month with the drier weather.

The Rangiriri section starts immediately north of the SH 1 intersection at Te Kauwhata and follows a new alignment closer to the Waikato River, joining onto the completed Ohinewai section of the expressway south of Rangiriri.




For more information please contact:

Natalie Dixon
Media Manager
Waikato and Bay of Plenty region

T: 07 928 7908
M: 021 928 413