Jane Nees BOP Regional Councillor www.janenees.co.nz

Our knowledge of science and the environment has been built up over many years. There are few ‘eureka' moments - it takes a lot of research, trial and error before we are sure we have the facts straight or the best solution.

And so it is with any activity that impacts on the environment. Our environment is a very complex ecological system, with very many variables and a small change in any one of these can lead to an unanticipated result.

So it is no surprise that some concerns are surfacing - despite trials of various methods, a rigorous resource consent process, mulching by a machine with a low pressure footprint to remove the mangroves, and months of mechanical removal. There are many variables at the different sites – the depth of the underlying sediments, the density of the mangroves, the strength of the current flow, the speed of sediment mobilisation, and the proximity and numbers of wildlife that can colonise areas previously occupied by the mangroves. Even the amount of sea lettuce in the harbour, the ambient temperature, and the amount of rainfall will have an impact on how quickly the mangrove mulch decomposes.

Like others, I have been worried about the black slime left by the decomposing mulch in some areas, and the sea lettuce snagged on the remaining stumps in others. I am concerned about how long the mulch is likely to stick around. I worry about what negative impacts on the harbour may possibly arise if we don't get the removal process right. It has been a learning process for us all, and what is most important is that the Bay of Plenty Regional Council exercises adaptive management in the removal of mangroves from our harbour. It is essential that we continue our work on mangrove removal. If we don't, we will lose our beautiful estuarine areas and access to the harbour in many places. Stopping the removal of mangroves is just not an option for me – we need to be doing more not less – and prioritising the areas that need urgent action.

The current concerns which have been raised by Forest and Bird and some members of the community, and the early research by NIWA on harbour impacts, do need serious consideration. However, some estuary care groups who have had areas cleared have been very satisfied with the results, and want more of their mangroves cleared. We need to be stepping up our monitoring of the impacts of our current clearing operations. We need to talk to those with experience in the field – unfortunately we are breaking new ground so this is not an easy task. We need to be asking – is there a real problem? Is there a better way?

This week the Regional Council has had discussions with many different people on the mangrove issue. There are a number of options. Our resource consent has a clause which enables some adjustment of the way things are done if there are problems. We will consider what we can do under this clause. We need to be clear about the nature of the problem and where it is occurring, so that we can evaluate possible actions. Regardless, we will trial different ways of doing things - especially for areas of high density mangroves. Things we will look at include removal of the mulch and ways of encouraging mulch dispersal. Different methods of mangrove removal could be considered. In the interim, it is likely we will only use the mulcher in areas where we are sure the mulch will disperse. This may slow things up a little, but it is worth taking a little time to get it right. You can be sure that we all want the very best for our harbour, and will work hard to find a sustainable solution for the future.

If you have any views on this or any other issue, please contact me on neesj@xtra.co.nz or ring me on 07 579-5150. Or you can check out my website at www.janenees.co.nz