Boat electrofishing survey of Lake Ngaroto

Abstract

Lake Ngaroto, a 130-ha hypertrophic lake located near Te Awamutu, has previously been found to contain a diverse fish fauna of both native and introduced fish. Native fish in the lake are common bullies (Gobiomorphus cotidianus), shortfin eels (Anguilla australis), longfin eels (Anguilla dieffenbachii) and common smelt (Retropinna retropinna). Introduced species include goldfish (Carassius auratus), brown bullhead catfish (Ameiurus nebulosus), rudd (Scardinius erythrophthalmus), gambusia (Gambusia affinis) and koi carp (Cyprinus carpio), with some koi carp/goldfish hybrids. As part of the ongoing research of the invasive fish research programme, run by the Centre for Biodiversity and Ecology Research (CBER), current baseline values for species abundance and indigenous biodiversity need to be established for at least 5 Waikato lakes over 5 ha in size, with Lake Ngaroto selected as a candidate.