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Rare white rātā in Lower Hutt, rarer than the kākāpō

It is rarer than the kākāpō and most people have never heard of it but a population of Bartlett’s white rātā is thriving in Lower Hutt.

Te Papa

Hutt City Council staff recently used a drone to survey trees in Percy Scenic Reserve and made an unexpected discovery.

One of the seven Bartlett’s rātā was flowering, which means it has the potential to be used in a project that is trying to save the critically endangered tree.

There are only 13 Bartlett’s rātā left in the wild and the population is too spread out for pollination.

Botanists and scientists from a number of organisations including Te Papa and Otari Wilton Bush are working to save the rātā, which only survives on three sites in the Far North.

Otari Wilton Bush manager and president of the New Zealand Plant Conservation Network Rewi Elliot said the beautiful tree faced an uncertain future.

Bartlett’s is the only white tree rātā and it has been decimated by possums and habitat destruction, and is also under threat from Myrtle rust.

It was discovered in the 1970s and since then the wild population has fallen from 34 trees to 13.

Although there are a number of Bartlett’s in cultivation, they are mostly clones from a single tree.

Otari Wilton had a cutting from a tree from Spirits Bay, which was planted in 1992. It did not flower until 2017 and Elliot said botanists were trying to work out how to pollinate it by hand.

Botanist were also working on how to store the seeds with Myrtle rust poising a major threat

It was not clear if climate change was having an impact but with so few trees left in the wild finding a way to germinate and store the seeds was critical.

Although most people had never heard of white tree rātā , he said the species was more at risk than the kākāpō and other high-profile bird species.

“The reason people should consider it important is because if there are no plants there are no animals and that is a fact.”

In the long term the aim was to create a healthy viable wild population and Elliot said the future of the species was  hanging in the balance.

White beauty

* Its conservation status is Threatened – Nationally Critical.
* Auckland school teacher John Bartlett discovered the species in 1975.
* It is the same genus as the pōhutukawa, which is also under threat from Myrtle rust.

Nicholas Boyack/Stuff