Caulerpa partial lifting of Lake Macquarie netting bans

A recent survey in Lake Macquarie has found that all but one of the sites previously known to be infested with the invasive weed Caulerpa taxifolia are now weed free.

This dramatic reduction from a peak of around 4 hectares in 2001/02 comes after an intensive control programme by the NSW Department of Primary Industries (DPI).

We have worked very hard to eradicate Caulerpa from Lake Macquarie, since 2002 using more than 750 tonnes of pool salt to kill beds of this aquatic weed in the lake.

Although the latest survey results are welcome we must remain vigilant, as the exact reasons why Caulerpa appears and disappears are still not fully understood.

The absence of the weed around Pulbah Island and Wangi has led to the removal of the netting bans in this area; however a netting closure remains in place in the Vales Point/Mannering Park area.

This closure, which is clearly marked with yellow buoys, extends from the tip of Vales Point to the Vales Point Power Station inlet.

Within the closure area the use of any net, except a landing net used with a fishing rod or handline is prohibited. This prohibition includes hoop nets, also known as “witches’ hats”, for catching crabs. 

The small patches of Caulerpa that remain in the Mannering Park area were treated with 48 tonnes of salt in early June.

NSW DPI is encouraging water users to avoid this area where possible, so fragments of the weed are not transferred to other parts of the Lake.

We are also asking residents to keep a lookout for the weed in other parts of the Lake, and to report any new sightings immediately.

New warning signs are being erected at boatramps around the lake to remind residents and visitors to watch out for the weed.

Caulerpa taxifolia is an extremely fast growing noxious weed that can easily regenerate from pieces that break off existing plants.

The NSW Government is spending nearly $1 million a year to improve the management of aquatic pests with a major focus on controlling Caulerpa taxifolia. NSW DPI has developed a variety of methods for fighting Caulerpa, including handpicking, smothering and applying salt which, in most situations, has proved the most effective means of control.

Report any new sightings of Caulerpa by calling the NSW DPI aquatic pest species hotline on 4916 3877.