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Waihou and Piako ecological monitoring 2018

TR 2018/28

Report: TR 2018/28

Author: James Shelley, Elizabeth Graham, Paul Franklin, Peter Williams, Nicola Pyper (National Institute of Water & Atmospheric Research Ltd (NIWA))

About this report

The Waihou and Piako instream ecological monitoring is annually recurring work and the long-term monitoring results will be used to detect trend changes in instream ecological composition. If we detect any significant changes in ecology, we will need to consider changing the way we manage water. This long-term accumulation of ecological data will also be valuable for next round of Waihou and Piako catchment investigations which will happen 15 years in future. These catchment investigations will update water allocation limits for these rivers. The report shows, this year, there was no consistent pattern in direction of change in fish population. Macroinvertebrate community index showed similar pattern as was in previous years, except for the Wairere stream, where it showed notable decline this year; this was linked with a large increase in periphyton sliminess at the location. Otherwise, all sites showed quality staying within same range as previous years. Sites that showed decline last year recovered this year.

Read or download the report

Waihou and Piako ecological monitoring 2018 [PDF, 4.7 MB]

Contents
1 Introduction
2 Methodology
2.1 Sites
2.2 Flow
2.3 Fish
2.4 Macroinvertebrates
2.5 Macrophytes & periphyton
3 Results
3.1 Piako catchment
3.2 Waihou catchment
4 Discussion
4.1 Piako catchment
4.2 Waihou catchment
5 Conclusions
6 Recommendations
7 Acknowledgements
8 References