Back in 2019 Baybuzz published The kahikatea are dying, which looked in depth into the fate of Hawke’s Bay’s last remnant of alluvial kahikatea forest, in the Inglis Bush Scenic Reserve near Onga Onga beside the Tukituki River.
The reserve is also home to a population of thumb-sized long-tailed bat (pekapeka), NZ’s only native mammal and critically endangered.
At the time, the hypothesis was that these trees were a casualty of large-scale irrigation, with water drawn from the Ruataniwha aquifer, which diminished the springs feeding the reserve. As far back as 1996 a Landcare Report observed: “The Reserve should be regarded as having as much right to water as any other land use or user. At present, increased agricultural use is already seen to be prejudicing the Reserve, as manifest in the failure of the seepage springs.”
Nearly 30 years later, with sharply rising water extraction for irrigation, nothing has been done to address the situation.
Weeks ago, CHB conservationist Clint Deckard flew a drone over the reserve, producing this video showing the spreading death of the kahikatea.
The video will be part of Deckard’s evidence to be presented to the Environment Court in opposing an allocation of another 15 million cubic metres of water from the Ruataniwha aquifer.
Here’s what Deckard tells us today:
“A comprehensive study by a multi-disciplinary team from the Department of Conservation and the Hawke’s Bay Regional Council in 2021 determined that the death of the Kahikatea was most likely caused by the failure of the springs that have fed this area for hundreds of years. Other causes have been ruled out.
“The springs appear to be connected to the deeper aquifer and mirror the decline in the aquifer level. These trees could be seen as a sentinel species, the equivalent of the canary in the mine. Their death should be a wakeup call for all, especially those tasked with protecting our environment. The Ruataniwha Basin is in trouble and the Kahikatea are a clear sign of what can result from over allocation of our ground water.
“Despite all the investigations and reports about the reserve, nothing has been done to alleviate the situation.”
For its part, HBRC was unable to provide a human response this week, referring me instead to a stale paywalled April 2021 article in HB Today that included a quote from a staffer no longer employed by HBRC, with a message saying “We won’t make any further comment”. That’s a creative use HBRC Comms dollars! I take the response to mean: We don’t know or won’t admit what’s killing those trees.
Water being taken from the aquifer in CHB for farming at greater levels – and the demand for even more with a dam being continually suggested – seems to have dire effects on everybody except the farmers. CHB has always been dry land farming and the proliferation of orchards, dairying and so on must have a huge effect on the aquifer as more and more water is used for irrigation. The powers that be should be viewing all this on an urgent basis before we actually lose our environment totally and replace it with cows and fruit trees while water restrictions start becoming more frequent during summers for households
Very sad – I hope Clint Deckard’s report will be taken seriously by the Environment Court as it needs to be.
I take HBRC response to mean: We don’t care.
BNZ and Peter Fraser both costed water from the “Ruataniwha” dam at 53 cents/cubic metre.
When a “tax” of 7 cents/cum was suggested by the Labour Government, farmer organisations clamoured that it would bankrupt them — Really??
Now HBRC is again supporting farmers at the expense of ratepayers and the environment. Prof. Moot is just one of those who have shown irrigation need not be essential in Canterbury. This has also been demonstrated in CHB. Production and profit are linked, but ONLY when the marginal return from the additional product exceeds the additional costs. The true cost of irrigation is $negative and environmentally destructive.
When we get the ECONOMICS right, the environment will follow.
HBRC seems unable to grasp this concept,.
We have a 13ha stand of old native forest on our farm near Elsthorpe and it seems since Cyclone Gabrielle a large number of big old Kahikatea are dying, I don’t know why, but it’s not from a lack of water???