Mud crab indicators for the 2023 Gladstone Harbour Report Card

Giant mud crabs (Scylla serrata) are a recreationally and commercially important species across the Indo-Pacific, an iconic seafood item, and have cultural value to Indigenous Australians. The Gladstone Harbour Report Card mud crab indicator has been monitored in seven Gladstone Harbour zones since 2017, and this report presents the results of the seventh year of sampling, in 2023. The indicator scores and grades cover three metrics: abundance (catch per unit effort), prevalence of rust lesions, and sex ratio, in each zone and across the harbour. Two field sampling events were conducted in February and June 2023. Scores and grades were calculated using both of the 2023 data sets for the three metrics within each of the seven recommended long-term monitoring zones in Gladstone Harbour.