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Published: 2007-04-05 00:00:00

This column was written by Councillors Ian Balme, Lois Livingston, David Peart and Paula Southgate. from Environment Waikato.

The fight against introduced pests like possums and stoats, and pest plants like old man’s beard, has been going on for more than 100 years. It has been a seesaw battle, but until recently the pests have generally had the upper hand. And of course our predecessors shot themselves in the foot several times by intentionally introducing creatures that would have been better left in their native environments. The losses to New Zealand have been both tragic (native birds driven into extinction) and costly (almost incalculable agricultural losses).

Several things have changed in the last few years, however, that make the future look slightly brighter. First, the public and governmental awareness of the potential threat from introduced organisms is higher than ever before. This applies not just to the risks of new organisms breaching our border controls, but also to our understanding of the damage done by pests already here. The best example is the growing awareness of the enormous damage that ship rats cause to our native ecology.

Second, the technology used to control pests has improved dramatically. Thirty years ago it would have been inconceivable to think of eliminating all animal pests from large, rugged bush areas. Now, however, pest eradications are almost commonplace. The Hamilton area is fortunate to have one of the most impressive examples of that right on its doorstep through the work of the Maungatautari Ecological Island Trust.

These changes don’t mean we are winning the war, but they do give us confidence that we can deliver more effective strategies and better outcomes.

Like all regional councils, Environment Waikato has a responsibility to control plants and animal pests (under the Biosecurity Act) and to protect native biodiversity (under the Resource Management Act). These responsibilities have come together in EW’s proposed five-year Regional Pest Management Strategy that is available for public comment until April 10.

Environment Waikato is proposing to structure its pest control programmes around ‘regional priority areas’ focusing on three main goals: protecting biodiversity in high value areas, reducing erosion and flooding in steep catchments, and keeping possum numbers low in areas that have already been treated.

At the moment, about 70 per cent of the region is benefiting from pest control work done by Environment Waikato and others. We want to raise that figure to 90 per cent within five years. This would include doubling the amount of land where pest control protects native birds and other species.

Hamilton city benefits from pest control in a number of ways. Firstly, in the 2007/08 year Environment Waikato will be carrying out significant work to control plant pests. Alligator weed, an aggressive threat to ponds, streams and land is the biggest concern. The cost of controlling this weed has grown considerably in the past three years as new infestations have been found in the city, mostly in new subdivisions.

City residents also benefit from plant pest control undertaken for environmental reasons. Environment Waikato controls invasive plants such as evergreen buckthorn, old man’s beard, and moth plant. We also collaborate with Hamilton City Council to enhance gully systems by reducing plant pest infestations and actively replanting with native species. Starting in the next month, Environment Waikato will have one full time staff person almost entirely dedicated to plant pest control in the city.

Second, there will be more native birds in city gardens thanks to the proposed ‘Hamilton Halo’ project that will control rats in bush areas surrounding Hamilton. If tui and other birds can breed safely in those areas then there will be more birds coming in to Hamilton to feed in our parks and gardens. Hamilton residents will also benefit from Environment Waikato’s work to enhance biodiversity in some of our favourite tramping areas. Next year, for example, Environment Waikato and DOC are co-operating to tackle pests on about 75,000 hectares on and around Mt Pirongia. This kind of partnership can reduce costs for everyone.

Like other parts of the region, the city has also benefited economically from the millions of dollars spent to control possums that can spread Tb to cattle and deer. This work has been a huge benefit to the agricultural economy that surrounds and helps sustain Hamilton. The programme has been funded from national sources with a Waikato contribution. While Waikato farmers will continue to pay their share through Animal Health Board levies, the national programme will soon start directing funding to other parts of the country. We can either choose to maintain the gains made under that programme or let possum numbers rebound, with all the associated environmental damage. The regional council believes that would be irresponsible and a waste of the millions of dollars invested already. Everyone in the community will benefit if we can maintain the gains we have made in pest control so far.

How much is it worth to you?

Pest control has many benefits for both urban and rural residents. Some benefits area easily measured – like the economic gain from controlling Tb in cattle and deer – while some are harder to quantify in dollar terms – like bringing native birds back to our parks and gardens.

Most of these are widespread regional benefits, which is why the regional council has proposed a new way to collect rates that fund pest control. Right now, funding comes from a mix of various targeted rates, plus a portion of the general rate that everyone pays. The new proposal would replace all existing pest control rates with one single targeted rate of about $8 per $100,000 of capital value. No rating system is perfect but the council believes this method would be a better reflection of the ‘public good’ benefits communities across the region get from pest control.

A key question for the regional council is whether the public supports the cost of doing this increased pest control. In Hamilton, the additional cost would be about $12 for a typical property value of around $300,000. That would mean an increase from about $13 to $25. All across the region, doing more pest control next year would cost most people around $20 more in rates. However, the impact will vary depending on the size and value of each property.

You can find out more about Environment Waikato’s pest control proposal at Submissions must be received by April 10. If you are most interested in the costs of pest control, take a look at Environment Waikato’s Draft Annual Plan and get your comments in before May 2. More information is available by calling the Environment Waikato freephone, 0800 800 401.

Submissions to the RPMS can be emailed to, however we do ask that you also post or fax a signed hard copy of your submission to (07) 859 0998 (this can be sent after your email) to satisfy the requirements for signatures and formal receipt of submissions.