COMPARISON OF DORSAL AND VENTRAL TAG RETENTION IN WESTERN ROCK LOBSTERS, PANULIRUS-CYGNUS (GEORGE)

Over 13 000 western rock lobsters double-tagged in Western Australia w ith dorsal and ventral tags between 1992 and 1995 have been recaptured . Ventral tags suffered significantly less damage over time (P < 0.001 ) than did dorsal tags. Dorsal tag durability was significantly less ( P <0.001) for lobsters in shallow (<37 m) than deep (>37 m) water. Fur thermore, dorsal tags returned from the Abrolhos Islands showed substa ntially more mutilation and loss than did those from the coast (P < 0. 001), and even within the coastal areas there were significant differe nces (P < 0.05) between management zones. Tag durability was less in a reas of high lobster density than low, but was not influenced by the s ex or size of the animals.