Port Waikato Riparian Enhancement Project

In 2002 Genesis Energy began a project to enhance Inanga spawning and feeding grounds of the Lower Waikato River. An area in the lowermost reach of the Whauwhautahi Stream was selected as a suitable location for the enhancement project. The project aims to enhance Inanga spawning and feeding habitats through works such as fencing, planting, and channel and pond construction etc. Whitebait (Inanga) were chosen as the focus of the enhancement project because of their cultural significance to Tangata Whenua and also because of the threatened status of a number of whitebait species.

The enhancement of the Whauwhautahi Stream included:

• Fencing of the area so that any Inanga eggs would not be trampled by cattle.
• Planting of the area with indigenous trees, shrubs and grasses to provide cover and food for fish.
• Creation of channels and ponding areas to increase fish habitat and improve access to spawning and feeding areas on the river margin.
• Creation of sloping banks where Inanga can spawn.
• Removal of weeds and ongoing maintenance to ensure indigenous plants establish and provide continuous cover.

Outcomes of the Whauwhautahi Project

Monitoring of the area in 2006 showed that there were significantly more adult Inanga in the constructed pond and channel leading to the pond (channel 6) compared to a non-enhanced site.

Plantings are also becoming well established with species such as Manuka, Pukatea and Kahikatea present in the area.

Ongoing Maintenance

Genesis Energy carries out ongoing maintenance in the area to ensure the success of the project. This has included control of possums and pest plants such as gorse and woolly nightshade as well as removal of weeds to help the establishment of indigenous plants.