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Fishery Bulletin 92(2), 1994 



had heavier tissue wet weight than wild conch (slopes 

 were homogeneous, F=0.163, P=0.688; ANCOVA: 

 F=7.12, P= 0.010) (Fig. 7C). This can be explained 

 by examining the ratio between tissue and shell 

 weight. At the beginning of the experiment these 

 ratios for hatchery and wild conch were 0.34 ± 0.04 

 and 0.22 ± 0.03 (mean ± SD), respectively. This indi- 

 cates that hatchery conch had lighter shells and 

 heavier soft tissue than wild conch. At the end of the 

 experiment ratios for hatchery and wild conch were 

 0.30 ± 0.04 and 0.25 ± 0.04 (mean ± SD), respectively. 



The lower ratio for hatchery conch indicates that both 

 the tissue and shell weight were increasing. 



Hatchery-reared conch that survived 11 months 

 in the field either developed morphological charac- 

 teristics of wild conch, or the survivors had such char- 

 acteristics at release. Because there was little over- 

 lap in regressions of shell width versus shell length 

 at the beginning of the experiment, change in shape 

 is the most plausible explanation for characteristics 

 measured in hatchery-reared conch at the end of the 

 experiment. Presence of short spines on pretran- 



120 



en 



s 



I) 

 in 



S 



tn 

 P 



20 



120 



SO 90 100 110 120 



Shell Length (mm) 



Figure 6 



Shell weights (A), shell widths (B), and tissue 

 weights (C) of hatchery- reared and wild queen conch, 

 Strombus gigas, shown as a function of shell length. 

 Measurements were taken for conch of each stock 

 type collected at the beginning of the free-ranging 

 experiment ( 1 April 1990). 



