Rock Lobster Enhancement and Aquaculture Subprogram: investigation of tail fan damage in live-held adult rock lobsters
University of Adelaide
Mike C. Geddes
FRDC Rock Lobster Enhancement and Aquaculture Subprogram Project 98/305 investigated the environmental and system requirements for juvenile and adult rock lobster holding and grow-out. Results from this Project showed that adult southern rock lobster can be held long-term in industry facilities with high survival rates and that condition and weight can be improved. However, in order for a large-scale industry to develop in this area, there is a definite need for research aimed at reducing the incidence of tail fan damage in live-held adult southern rock lobster. Tail fan damage has also been identified by the Geraldton Fishermens Co-operative as a problem with live-held western rock lobster prior to live export.
1. Investigate potential causes of tail fan damage in live-held adult southern rock lobster.
An earlier project on liveholding of adult southern rock lobster, RLEAS 98/305, demonstrated that adult SRL could survive, feed, moult and grow when held in sea cages or raceways and fed an artificial diet developed in RLEAS 98/303. The major obstacle identified to such an industry was that lobsters live-held at ambient temperatures developed a tail fan disease involving melanization and loss of tissue. We have named this condition tail fan necrosis (TFN).
Lobsters with advanced TFN are not acceptable for live export market and this limits any live-holding industry. There was a need to characterize the TFN condition, to see if it was correlated with environmental factors such as holding conditions
(density and feeding patterns) and temperature. The microbial species involved in TFN needed to be identified and their role in TFN verified. Finally ways of limiting TFN needed to be proposed.