The Threats
The values most at risk at Piha include loss of native bush due to invasive weeds; loss of fauna due to pest animals; loss of kauri to dieback disease; sand dune degradation due to pests, including exotic plant colonisation and rabbit browse, as well as trampling; health risks posed by wasps, possums, hedgehogs etc; negative lifestyle impacts of Argentine ants, wasps, rodents and pest plants; and declining asset values due to weed presence generally.
Piha provides a unique example of where being pest free can be achieved at lower cost than elsewhere and can confer greater regional benefits than at other locations. This is because Piha is essentially a small island of high pest indices surrounded by a great area of lower pest indices (the Waitakere Ranges Regional Park) and the Tasman Sea, meaning that currently rats, mice, rabbits, hedgehogs, Argentine ants, wasps and most weeds all tend to radiate out from Piha rather than come in from outside.
Maintenance of pest free borders can therefore be achieved at lower cost than in other locations. Furthermore, any effort at Piha would assist in reducing pest threats to the Park (and their cost), and essentially pilot options for Auckland Council’s (AC) recently declared Pest Free Auckland, establishing a baseline and monitoring and evaluation progress.
