Boosting natural diversity . . . Invasive crack willow trees will be removed at Lake Middleton later this year. PHOTO: SUPPLIED/ECAN

Invasive crack willow trees will be removed at Lake Middleton later this year, thanks to support from the Upper Waitaki Water Zone Committee.

The project, run by the Ohau Conservation Trust, received $11,000 to boost the natural biodiversity of the small lake, which sits beside the much larger Lake Ohau.

The lake has well›established crack willows growing on its eastern and south›eastern margins. The project aims to stop seedlings from these established crack willows spreading around the entire lake, by controlling them along 1.25km of the lake’s perimeter.

The trust worked with the Department of Conservation (Doc), who administer the reserve, to set up the project. A contractor will undertake the control work.

Trust chairwoman Viv Smith-Campbell said the project would help protect the indigenous species which called the lake and its surrounds home.

‘‘We know there are species based in the area, of at least 26 plants (aquatic and terrestrial), 14 invertebrates (aquatic), lizards, four fish, 27 birds, 66 algae/ phytoplankton, and four zooplankton,’’ she said.

Mrs Smith-Campbell said it was a special place with a rich biodiversity.

‘‘Of these species, two fish, nine birds, one aquatic invertebrate and two plants have a conservation status threat ranking of threatened or at risk,’’ she said.

The trust would monitor for regrowth and any new spread following the control operation.

‘‘If the funding is not all used on willow control, it is proposed the contractor use the chemicals on other plant pest species, such as broom, that is also found around the lake margins,” she said.

The Ohau Conservation Trust was formed in 2004 with the aim of promoting awareness of the area’s unique biodiversity, and undertakes projects to protect it.

As well as enhancing biodiversity, the willow control project also aligns with the zone committee’s plan to enhance mahinga kai opportunities. Mahinga kai is about the value of natural resources that sustain life, including the life of people.

Committee chairman Simon Cameron said it was important to manage and protect these resources, in the same way those before them had done.

‘‘By removing willows from around the lake, the natural environment will be enhanced and the natural resources will be more likely to be able to flourish,’’ he said.

‘‘It also fits with our plan for the preservation of recreational values of Waitaki lakes.’’

The project is set to start at the end of the year, and finish in February 2023.