Preliminary analysis of boat electrofishing in the Waikato River in the vicinity of the Huntly Power Station: Part 1 - fishing on 2 September 2013

Abstract

This report gives a basic summary of the first sampling of a three-part monitoring project for Genesis Power Ltd (Genesis) that the University of Waikato is undertaking in close collaboration with National Institute of Water and Environmental Research Institute Atmosphere Ltd (NIWA), Hamilton, Boat electrofishing results will eventually be combined with netting undertaken by NIWA in a final report to Genesis. The boat electrofishing survey took place on 2 September, the objective of which was to undertake the first of three surveys to estimate fish distributions and abundances over key seasons: 1. Early spring 2013 (end August/early September) to target peak trout abundances and cyprinid distributions during cooler months of the year. 2. Summer 2014 (Jan/February) to capture peak summer abundances for target indigenous and exotic species. 3. Winter 2014 (June/July) to target mullet and cyprinid distributions during cooler months of the year. At the surveyed reach is about 80 km from the sea, and at this point the Waikato River is a 7th order river with at a bed elevation of about 19.1 m above sea level. The catchment area upstream is 12,188 km², and the river has a mean flow of 352.3 m³ s⁻¹ and a mean annual low flow of 123.5 m³ s⁻¹ (Freshwater Fish Database Assistant version 6.1, I.G. Jowett).