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Fishery Bulletin 105(3) 



both sexes with size may indicate that larger individu- 

 als are more likely to survive the attack of a predator, 

 although perhaps with the loss of appendages. 



The effect of appendage damage on 

 reproductive output 



Appendage damage can lead to an associated reduction 

 in the reproductive output of female P. cygnus directly, 

 namely as reduced proportions of females that develop 

 ovigerous setae, and as a reduction in the proportions of 



80 100 120 



Carapace length (mm) 



Figure 6 



The relationship between total egg production (total fecun- 

 dity) and carapace length (mm) of female western rock 

 lobster (Panulirus cygnus) in one season at the Abrolhos 

 Islands (zone A) with none, one, two, or three damaged 

 appendages. 



ovigerous females that will produce one or two batches 

 of eggs within a season. Reproductive output is also 

 affected indirectly when females with appendage damage 

 do not molt into breeding condition (with ovigerous 

 setae); a female above the legal minimum size without 

 ovigerous setae can be legally retained by commercial 

 and recreational fishermen and thus her contribution to 

 the broodstock is removed. 



The significant reduction in reproductive output of 

 female P. cygnus with appendage damage is not sur- 

 prising, because regeneration places large demands on 

 energy reserves, often in the form of a reallocation 

 of resources that were originally destined for repro- 

 duction and growth (Demeusy, 1965; Norman and 

 Jones, 1992; Juanes and Smith, 1995). Moreover, 

 if appendage damage is extensive, the process of 

 regenerating multiple appendages may result in a 

 long-term reallocation and an overall increase in 

 energy demand (McVean, 1982). 



Most P. cygnus caught during the survey were in- 

 tact when examined; less than 15'7f of the entire 

 catch had damaged appendages. This 15'7f was prob- 

 ably due, in part, to management measures based on 

 previous work on the effects of appendage damage 

 (Brown and Caputi, 1985, 1986) to initiate changes 

 aimed at reducing limb loss. Methods for limiting 

 appendage damage even further are being developed, 

 i.e., cold stunning (Davidson and Hoskin, 2002). How- 

 ever, even with the best intentions, some appendage 

 damage through handling is unavoidable. 



This study has highlighted that management mea- 

 sures aimed at protecting the western rock lobster 

 broodstock inevitably result in the animals being 

 handled more than once (or multiple times) in the 

 course of the fishing season, and the damage to ap- 

 pendages caused by handling produces a significant, 

 and previously unrecognized, effect on the overall 

 egg production of this resource. These effects need 



