Gladstone Fish Health Investigation 2011 - 2012 - Western Basin ...

4,000Commercial effort (days fished) for mud crab in the Gladstone region2000 - 20123,5003,0002,500Days2,0001,5001,00050002000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012YearFigure 16. The number of days fishing where commercial fishers have reported mud crab from theGladstone region (CFish grid S30), as reported in commercial fisher logbooks (calendar years 2000 –2012).Crab size structureConcerns were raised that fishers were not catching large numbers of juvenile (undersize)crabs during normal commercial fishing activities. These concerns were investigated, as theyrelate to recruitment and mud crab catches into the future for the Gladstone region.To illustrate the size structure of the catch, crabs caught during the program werecategorised as legal male, large female (≥ legal size limit for males) or undersize (males andfemales combined).Phase 1: During Phase 1, mud crab sampling was conducted between December 2011 andJanuary 2012. A total of 1435 crabs were caught with their size and sex recorded. Thepercentage of undersized crabs varied between sites within Gladstone, with the percentageof undersized crabs ranging between 34.67% (Rodds Bay) and 50.91% (South Trees Inlet).The percentage of undersized crabs caught in the Fitzroy River was 42.14%, while nosampling of mud crabs was conducted in Bundaberg during this phase of the program (seeFigure 17).38