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

Observational findings Phase 2April 2012: During trawl sampling in April, the catch of banana pawns at each location was150 kg or greater. Due to the size of the catch, observations were made from a sub-sampleof at least 100 prawns at each location.A single prawn was collected in the Gladstone Harbour and one from the offshore FitzroyRiver site with shell erosion. A single prawn at Bundaberg and a single prawn from theoffshore Fitzroy River sites were observed to be affected by an isopod parasite under the gillcarapace. No other signs of ill health were observed in banana prawns caught during thetrawl sampling.June/July 2012: Observations were made from the complete banana prawn catch at boththe Gladstone Harbour (approximately 1.5 kg) and offshore Fitzroy River sites (approximately2 kg). Due to the size of the catch at Bundaberg (approximately 200 kg) observations weremade from a sub-sample of 100 prawns.Two prawns collected from the Gladstone Harbour and one prawn collected from theoffshore Fitzroy River sites had minor shell erosion. Two prawns collected from the offshoreFitzroy River site and a single prawn collected from Bundaberg had isopod parasites locatedunder their gill carapace (see Figures 43 and 44). No other signs of ill health were observedin banana prawns caught during the trawl sampling.Figure 43. Banana prawns collected during the sampling program from (a) the Gladstone Harbour and (b)offshore Fitzroy River sites showing signs of shell erosion (circled).64