Abstract The Gladstone Healthy Harbour Partnership (GHHP) was established in May 2012 to assess the health of Gladstone Harbour following public concern about a range of fish health issues that emerged in 2011. The GHHP is responsible for producing an annual report card on the health of the harbour that includes social, cultural, economic and environmental health indicators. Fish recruitment and fish health were identified as important measures to inform the fish and crab indicator group. The objective of this study was to determine suitable species and develop a fish recruitment indicator for incorporation into the health grading for Gladstone Harbour. Following a trial survey in 2014–15, Yellowfin Bream (Acanthopagrus australis) and Pikey Bream (Acanthopagrus berda) were selected for the development of a fish recruitment indicator. A total of 26 sites in 13 zones were selected as survey sites. Surveys were undertaken using a standardised castnet method that had previously been used for recruitment surveys. Surveys were undertaken in 2015–16 and 2016–17. Historic data from surveys from 2011 to 12 to 2013–14 at a number of sites were also assessed to provide historic gradings. A modelling strategy using a negative binomial distribution was used to determine the total juvenile Bream catch per visit to a site. Bream productivity was initially assessed as Year × Zone in 2015–16 and Year × Site in 2016–17 and then averaged to provide a zone and a whole of harbour score on a 0–1 scale. This was then converted to an A-E grading to ensure consistence with the other indicators. Based on the grading score Bream recruitment was assessed for the whole harbour as D (poor) in 2015–16 and B (good) in 2016–17. The results from the 2 years of surveys, the trial survey and the historic surveys confirmed that Bream recruits provide a suitable fish recruitment indicator for the Gladstone Harbour report card.
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