The doors to our Whitianga and Paeroa offices will be closed for the summer break from 4pm on Friday, 20 December, while our Taupō and Hamilton offices will close for the summer break at 1pm on Tuesday, 24 December. All offices will reopen on Monday, 6 January 2025. To report air or water pollution, unsafe water activities in or on a river, lake or harbour, or make a general enquiry or information request during this time, call us 24/7 on 0800 800 401.

Close alert

Waihou and Piako ecological monitoring 2017

TR 2017/32
  1. Services »
  2. Publications »
  3. TR2017/32

Report: TR 2017/32

Authors: Elizabeth Graham, Paul Franklin, Kathryn Reeve and Peter Williams (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 there was a decline in bully population and macro-invertebrate community index during this year. These changes might be temporary fluctuation so we will see how these change in the next year’s monitoring effort. In general, there was an improvement in habitat quality score, largely associated with increase in riparian cover and bank stability.

Read or download the report

Waihou and Piako ecological monitoring 2017 [PDF, 4.9 MB] 

Contents
  Executive summary
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 Conclusion
6 Recommendations
7 Acknowledgements
8 References
  Appendix A - Habitat assessment forms
  Appendix B -  Fish surveys
Appendix C - Macrophytes and periphyton
Appendix D - Macroinvertebrate taxa list
Appendix E - Bully phylogenetic analysis