558 



Fishery Bulletin 94(3), 1996 



juveniles in the sound (33.3 juveniles/ha) occurred 

 in the MFR at 5-10 m, but the standard deviation 

 for this depth interval was more than twice the mean 

 (all other densities were 0, except 1 at 5.1 juveniles/ 

 ha). In contrast with adults, intersite differences for 

 juvenile densities in Exuma Sound were not signifi- 

 cant (Student's <-test, P>0. 2 for 2.5-5 m, 5-10 m, and 

 10-15 m). 



50 

 40 

 30 

 20 

 I 







50 

 40 

 30 

 20 

 10 







50 

 40 



3 



20 

 i 





 50 

 40 

 30 

 20 

 10 





 50 

 40 

 30 

 20 

 10 



50 

 40 

 30 

 20 

 10 

 

 50 

 40 



30 



:;o 

 10 

 



Bank 



D 12 ±6 (213) 



• 10 ±6 (472) 



P<0 001 



Shell 2 5-5 m 



» 



*..b^i 



Shelf 5-10 m 



□ 26 ±8 (144) 

 I • 28 ±6 (57) 

 P=0 08 



• • • 



£~L 



J7L 



Shell 10-15 m 



Shelf 15-20 m 



Q 21 ±5(60) 



• 27*6(150) 



P 10 001 



Shelf 20-25 m 



a 23 ±5 (70) 



• 28 ±6 (100) 



P<0 001 



Shelf 25-30 m 



□ 22 ±6 (63) 



• f. mch 



=u 



13 17 21 25 29 33 37 41 45 49 



Lip thickness (mm) 



Figure 3 



Frequency distribution of shell lip thickness of adult conch 

 on the bank and at 6 depth intervals in Exuma Sound on 

 the island shelf near WW in the marine fishery reserve 

 (columns) and in the fished area near LSI (points). Each 

 value on the x-axis represents a range of sizes starting 

 with the lower end of the size interval (e.g. 5-8). Mean lip 

 thickness l±SD) and sample sizes in parentheses are also 

 given for each distribution. Values for LSI are adapted from 

 Stoner and Schwarte 1 1994 1. P-values are for intersite com- 

 parisons iKolmogorov-Smirnov tests) 



The majority of juvenile conch at both sites were 

 found on the Great Bahama Bank. On the bank in 

 the fished area, interannual variation in the surface 

 area occupied by juvenile aggregations was high, 

 ranging from 8 to 44 ha in the flow field north of LSI 

 and from 2 to 87 ha in the Children's Bay Cay flow 

 field (Table 2). In the MFR in 1991, juveniles occu- 

 pied 125 ha. Although data for the MFR are avail- 

 able for only 1 yr, the surface area was nearly twice 

 a large as the average surface area occupied in two 

 flow fields over 6 yr in the fished area. In the MFR, 

 juvenile aggregations covered 3.849f of the bank area 

 surveyed, compared with a mean value of 1.62% in 

 the fished area. 



Larval surveys 



Densities of queen conch larvae were consistently 

 higher in the MFR near WW than in the fished area 

 near LSI. In 50 plankton tows made at the two sites 

 between 1993 and 1994, densities in the fished area 

 were always <6 larvae/10 m 3 and typically near 1-2 

 larvae/10 m 3 (Table 3). Densities in the MFR were 

 frequently an order of magnitude higher, reaching a 

 maximum of 55 larvae/10 m 3 in July 1994. Intrasite 

 differences were most notable in the MFR on 22 Au- 

 gust 1993 when the offshore station had 184 times 

 the density of veligers as the inshore station. How- 

 ever, results were variable, and during both June 

 cruises in 1993, the inshore station at the MFR had 



Marine fishery reserve 



Fished area 



25-5 5-10 10-15 15-20 20-25 25-30 

 Depth (m) 



Figure 4 



Juvenile conch density at 6 depth intervals in Exuma 

 Sound on the island shelf at the fished area near LSI 

 i Stoner and Schwarte, 1994) and at the marine fishery re- 

 serve near WW i this study). Values are mean (+SE). 



