The Advocate 2014/1

I have not written for some time. I had the occasion to go to England for 3 months and spent 3 months in Oxford and enjoyed the most peaceful holiday I have had. I have found it hard to pick up the pieces again on my return but feel acclimatised to pick up now. I am pleased that John Toogood who acted as Treasurer in my absence has accepted the position and relieved me of that responsibility.

Today I shall post the Annual Report for 2013. We face yet again another postage increase as of 1 July driving us closer to all communication being by way of the internet. Even the Post Office is sending accounts by way of the internet no doubt to save on postage. There are fewer people these days without internet making the probability of the paperless society a step closer.

The Annual meeting will be on the Saturday of Queen’s Birthday weekend. Saturday 31.5.2014. We hope that you can make it. We welcome new committee members and would urge you to consider putting your name forward. Our present committee members would be pleased to discuss with you.

We have in place the PhD study and the following is the media release announcing the study.





March 2014



David Hamilton, Professor of Biology and Lakes Restoration at the University of Waikato has received funding of $108,000 towards a doctoral research project aimed at understanding the biological processes in Lake Taupo that are responsible for fluctuations in the trout population.

This study, which is supported by the Tuwharetoa Maori Trust Board, is being funded equally by the WN Pharazyn Estate Charitable Trust, the Department of Conservation and the Taupo District Council in the interests of improving the Taupo fishery and the economy of the Taupo District.

Until quite recently the trout sports fishery in Lake Taupo went through a well-publicised depression in which the numbers and quality of the rainbow trout had declined to a level not seen since the early 1990s. Fortunately this trend seems to have been reversed whereby the size and quality of the trout have improved significantly. However, it is considered that this is an ideal time to undertake research to ascertain if it is possible to determine what brought about the decline and this subsequent most welcome and unexpected resurgence in the fishery. Research is needed to assess the interactions amongst nutrients, phytoplankton, zooplankton, smelt and trout as the linkages in the food web, particularly between zooplankton and smelt, are not well understood.

Also not  understood is how changes in environmental conditions in the lake impact the top of the food web (i.e. trout). The current evidence suggests that this is due to changes in resource supply in the lake. The hypothesis suggests that stable isotopic mapping of the food web to trace how specific elements are cycled through the food chain represents a promising avenue for investigation. An ecosystem level investigation to these links allows for an integrated study and could shed some insight into other issues such as catfish and macrophyte infestations. A detailed map of the food web is seen as the backbone of this research.

Already some progress has been made. First, a doctoral student, Simon Stewart, who has a Master of Science degree in Biology with first class honours from Canterbury University joins the project and Professor Hamilton will supervise Simon’s Ph.D. study. Secondly, a Scientific Advisory Group has been formed with representatives from Waikato Regional Council, TMTB, NIWA, DOC, GNS and other Waikato scholars.

A successful scientific study will help fishery managers to take the best possible measures to limit the impacts of imbalances in the populations of the various plants and animals in the food web which have occurred and provide them with another tool in their management tool box successfully to manage the Taupo fishery.

The funding for this study has been initiated by the Advocates for the Tongariro River.

For further scientific information contact Professor David Hamilton, [email protected], Simon Stewart, [email protected], Dr Michel Dedual, ([email protected]) on behalf of DOC and Dr Mark Cosgrove on behalf of The Advocates for the Tongariro River, [email protected]


Eric Wilson