Modelling Zero-inflated Fish Counts in Estuaries – A Comparison of Alternate Statistical Distributions
نویسندگان
چکیده
Freshwater flows have an important influence on the balance of fish species in estuaries. As well as supporting general ecosystem health, these flows are also necessary to comply with Australia-wide legislation aimed at the sustainable management of water resources. The Coastal Zone CRC and Fisheries Research and Development Corporation (FRDC) instigated the ‘environmental flows for estuaries’ project in three dry-tropics estuaries in central Queensland, namely the Fitzroy, Calliope and Boyne Rivers. The effects of the independent variables, including freshwater flows, on catch rates now need to be quantified. Typically, for each species the count data from the two-minute spatial and temporal trawl samples include many zeros, and are significantly skewed.
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