Top down or bottom up? Feasibility of water clarity restoration in the lower Karori Reservoir by fish removal

Abstract

As part of an overall ecosystem assessment of lower Karori Reservoir Sabctuary, Wellington, a number of variables are being monitored routinely, including temperature, nutrients, and phytoplankton and zooplankton populations. Ammonium (NH₄) tends to be the dominant species of inorganic nitrogen most of the time except in late winter when nitrate (NO₃) becomes dominant. Total nitrogen concentrations place Karori Sancturay in a mesotrophic to eutrophic category.