Push to return endangered native fish to Mahurangi waters

Jeremy Rees-Webbe with hatchery manager Lyn Hamilton-Hunter. Insert: A giant kokopu destined for Duck Creek. Photo, Lyn Hamilton-Hunter.

A Warkworth farmer plans to release hundreds of native fish into a stream running through her land in a bid to bolster the numbers of an endangered species in the wild, and it’s hoped other Mahurangi landowners will follow suit.

Shelley Trotter is awaiting permission from the Department of Conservation (DOC) to release 1000 giant kokopu into Duck Creek, where it crosses her land between Sharp Road and Sandspit Road.

Shelley has secured an offer of the fish from Mangakura fish breeder Jeremy Rees-Webbe, who feels the extensive fencing and riparian planting that Shelley has engaged in over the years has rendered the creek clean enough to support the re-introduction of the fish.

Shelley says she has been fencing and planting for around 30 years, continuing the work of her father before her.

She estimates that she has planted tens of thousands of trees.

In recent times, monitoring of the creek by environmental group Whitebait Connection has failed to detect giant kokopu (a species of whitebait), though they have found other native freshwater fish.

But Shelley says her older brother would sometimes see them when eeling at the creek as a child back in the 1970s, and occasionally a dead one would be found washed up on the banks of the creek following flooding.

Shelley says she has been advised that the release she plans often do not work because the conditions that prompted the demise of a fish species in a particular area are often still present and pose the same threat to newly-released fish.

However, she hopes the work she has done to reduce the amount of sediment in the creek will allow the introduced fish to survive.

She says survival chances improve with multiple releases, using fish of different ages to create a more natural environment.

Jeremy Rees-Webbe says he will be supplying giant kokopu aged between one and two years old and around 75mm-120mm long for the Duck Creek project, and he is giving the fish away for free.

Jeremy runs the Mangakura Pines Fish Farm and Hatchery – a non-profit organisation that aims to protect native fish species.

“I’m an older person and just feel it’s a worthwhile thing to do. I’m driven by it. Some people take up religion, I’ve taken up the giant kokopu,” he says.

He says a lot of farmers have done a “tremendous job” cleaning up their waterways, and he encourages them to get in touch to see if similar releases can be achieved on their properties.

However, he warns such releases still require DOC permission, which can be difficult to secure. He says DOC often takes the view that if waterways are improved, fish will re-inhabit them naturally, but Jeremy disagrees. He says it’s necessary to first create a fish population in the waterways in order to attract other fish.

He says the giant kokopu are almost extinct in the Auckland region, and he worries they will disappear entirely if something is not done.

Landowners interested in securing native fish to release into their own waterways should email Jeremy at rees-webbe@xtra.co.nz.