Includes bibliographical references (p. 27).

This study, conducted pursuant to Ministry of Fisheries project GMU200601, had two objectives: 1. To characterise the GMU 1 fishery, 2. To update the standardised CPUE index for grey mullet in GMU 1 with the inclusion of data up to the end of the 2005/2006 fishing year. Analyses were undertaken of the six geographical areas where most of the GMU 1 catch was taken: Lower Waikato River and southern coastal harbours (Stat areas 41 & 42); Manukau Harbour (Stat Area 43); Kaipara Harbour (Stat area 44); Northwest coast and harbours (Stat Areas 45, 46, & 47); East Northland (Stat Areas 2 & 3); Hauraki Gulf (Stat Areas 5, 6, & 7). Commercial catch and effort information, covering the period 1990 to 2006, came from the Ministry of Fisheries catch reporting database. Standardised CPUE indices were derived using Generalised Linear Modelling analyses (GLM). The basic observational unit was daily catch and the GLMs were used to explore the level of catch variation explained by fishing year and other potentially "explanatory" parameters including fishing-effort, vessel, and season. A stepwise procedure was used to assess the overall contribution of fishing-year and other parameters in the models; parameters that failed to increase model precision by more than 3% were dropped.