BROWN and CAPUTI: FACTORS AFFECTING GROWTH OF ROCK LOBSTER 

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C. NOV- DEC 1979 RELEASES 

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1980 



RECAPTURE MONTH 



Figure 1— The mean size (carapace) increment by month of recapture and the sample size involved in calculating it shown next 



to the points, for the three tagging trials at Two Rocks. 



around February was clearly evident in animals 

 caught from February 1980 onwards (Fig. 3, Ikble 1). 



Damage 



Damage to undersize rock lobsters was clearly 

 shown to have a detrimental effect on growth (Ikble 

 1), which was directly proportional to the level of 

 damage (Figs. 2, 3). 



Chittleborough (1975) found that growth incre- 



ment of i? cygrnts was reduced under laboratory con- 

 ditions when four or more legs were removed and 

 repetitive loss of two or more limbs led to precocious 

 molting with reduced molt increments leading to an 

 overall reduction in growth. Davis and Dodrill (1980) 

 and Davis (1981) undertook research on the effect 

 of injuries Oimb loss) produced by amateur and pro- 

 fessional fishermen and natural causes (e.g., 

 predators, molting accidents, etc) on the growth rate 

 of P. argus populations in the wild. They found that 



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