Weed Control Advances in Lake Wānaka Battle

  • Hon Chris Penk

A more than two-decade-long campaign to reclaim Lake Wānaka from an invasive aquatic weed has reached a major victory, with 40 kilometres of shoreline now successfully cleared. 

"This milestone marks a real triumph for the beautiful Lake Wānaka ecosystem and for everyone who treasures this iconic place," Land Information Minister Chris Penk says. 

"For the first time since 2013, Land Information New Zealand (LINZ) has been able to shift the lake's containment line, the invisible boundary separating weed-free and infested waters, marking real progress in a long and determined fight to turn the tide in our favour. 

"Lagarosiphon grows extremely quickly and forms dense, thick mats. Left unchecked it can choke waterways, smother native plants, and ruin how we use and enjoy our lakes.

"All it takes for a new invasion is a tiny fragment carried by a boat, a fishing line, and lake users moving between different bodies of water.

"The clearing of lagarosiphon is a testament to the sustained commitment of LINZ, its partner agencies, local groups, and the wider community, who have shown the power of working together to protect our freshwater ecosystems. 

"Innovative control methods, particularly the use of hessian mats, have been vital on the frontlines, acting like underwater shields that suppress lagarosiphon while allowing native vegetation to regroup and reclaim ground. 

"Today's good news and the shifting of the containment line prove we have won a key battle, but the war against this aquatic invader is not yet over. 

"Ultimately, the goal for LINZ is to keep pushing that containment line further south towards Roys Bay near the Wānaka township, and we will need every ally we can get. 

"I want to acknowledge the lake users who have been diligent in checking, cleaning, and drying their gear and to urge them to keep up the good work.

"Their ongoing vigilance is crucial to preventing this aquatic enemy from regaining a foothold and to ensuring we maintain the progress we have made."

Notes to editor:

  • This work is funded by LINZ, Queenstown Lakes District Council (QLDC) and Otago Regional Council (ORC), with support from the Lake Wānaka Aquatic Weed Management Committee. 
  • The committee includes LINZ, QLDC, ORC, Department of Conservation, Guardians of Lake Wānaka, Kāi Tahu, Wānaka Marina Limited, and Fish and Game Otago Region. It also includes representatives from LINZ's biosecurity delivery partner Boffa Miskell Limited and Earth Sciences New Zealand, who provide scientific advice.
/Public Release. This material from the originating organization/author(s) might be of the point-in-time nature, and edited for clarity, style and length. Mirage.News does not take institutional positions or sides, and all views, positions, and conclusions expressed herein are solely those of the author(s).View in full here.