Processes affecting the estimation of the size at onset of maturity (SOM) using ovigerous setae were investigated in southern rock lobsters Jasus edwardsii. Comparison of estimates of SOM based on ovigerous setae in samples collected during summer months (December-March) with those based on the presence of external eggs from winter months (June-August) indicated that ovigerous setae provide an accurate classification of maturity. Females with partially developed setation on pleopods are frequently observed in research catch-sampling projects and their maturity status was unclear. Our results show that these females with partially developed setae are most appropriately classed as immature, based on comparison between estimates of SOM determined by presence of external eggs or setae. The seasonal timing of field sampling affected estimates of SOM based on ovigerous setae, though tag-recapture data indicated that this was not associated with a loss of setae during a second annual moult. Estimates of SOM for populations of Jasus edwardsii around Tasmania can be based on maturity classification using ovigerous setae but care should be taken to ensure that seasonal timing of sampling is consistent.

Item Type:	Refereed Article
Research Division:	Agricultural and Veterinary Sciences
Research Group:	Fisheries Sciences
Research Field:	Fisheries Management
Objective Division:	Animal Production and Animal Primary Products
Objective Group:	Fisheries - Wild Caught
Objective Field:	Fisheries - Wild Caught not elsewhere classified
Author:	Gardner, C (Professor Caleb Gardner)
Author:	Mills, D (Mr David Mills)
Author:	Frusher, SD (Professor Stewart Frusher)
ID Code:	34450
Year Published:	2005
Web of Science® Times Cited:	4
Deposited By:	TAFI - Marine Research Laboratory
Deposited On:	2005-08-01
Last Modified:	2010-05-05
Downloads:	0