560 



Fishery Bulletin 94(3). 1996 



magnitude (Table 5). Mean values in the MFR near 

 WW for each depth interval were always >34/ha, well 

 above those reported for Bermuda, Florida, Puerto 

 Rico, and the U.S. Virgin Islands. Densities in the 

 MFR in depths >10 m were comparable to those ob- 

 served before 1984 at Cabo Cruz, Cuba, in the Turks 

 and Caicos Islands, and at a fished area of Venezu- 

 ela. Only two other studies quantified adult conch 

 densities by depth (Table 6). In Puerto Rico, maxi- 

 mum adult density occurred at 20-25 m, but the 

 value was only 0.05 adults/ha (Torres Rosado, 1987), 

 three orders of magnitude lower than that for our 

 MFR, and two orders of magnitude lower than that 

 at our fished area near LSI. In the U.S. Virgin Is- 

 lands, adult density was maximum ( 17.1 adults/ha) 

 at 18-24 m (Friedlander et al., 1994), and nearly 

 identical to densities ( 18.3 adults/ha) observed in 20- 

 25 m in our fished area. 



Highest densities reported in the literature were 

 observed >20 years ago in Cuba and >10 years ago 

 in Venezuela. The highest single density estimate in 

 our study (568 adults/ha) represented only 30-367r 

 of the highest densities reported for Diego Perez, 

 Cuba (1,582/ha), and for a fishery reserve at Islas 

 Los Roques in Venezuela (1,886/ha) (Table 5). This 

 protected area in Venezuela was subsequently de- 

 pleted of adult conch through illegal fishing 

 (Rodriquez and Posada, 1994), and declines in popu- 

 lation density throughout the Caribbean are well 

 documented (Appeldoorn, 1994a). Densities of conch 

 in the Exuma Cays are now among the highest in 

 the region. 



Low numbers of adults found in shallow water have 

 been attributed directly to fishing off the Turks and 



Caicos Islands (Hesse, 1979), Venezuela (Weil and 

 Laughlin, 1984), Puerto Rico (Torres Rosado, 1987), 

 the U.S. Virgin Islands (Friedlander etal., 1994), and 

 the Bahamas (Stoner and Schwarte, 1994). In this 

 investigation there were >31 times the number of 

 adult conch on the bank in the MFR compared with 

 the number in the fished area. Because any adult 

 conch living in water <10 m deep near LSI can be 

 collected easily by abundant free-diving fishermen, 

 we also attribute density differences between our 

 sites at least partly to fishing, although other expla- 

 nations are also plausible (see below). 



Densities of queen conch larvae have been reported 

 in only two published studies. Our estimates of den- 

 sity near WW, commonly >30 veligers/10 m 3 , were 

 much higher than these studies. The highest den- 

 sity from a cruise in the eastern Caribbean in 1988 

 was only 1.2 veligers/10 m 3 (mid- and late-stages) 

 near the Grenadines (Posada and Appeldoorn, 1994), 

 and the highest value found near Puerto Rico in 1993 

 was only 0.68 veligers/10 m ! (Appeldoorn and 

 Rodriquez 1 ). The highest single value recorded for a 

 site outside the Exuma Sound was 2.0 veligers/10 

 m 3 (including newly hatched larvae) in the Florida 

 Keys in 1994, with all other values one or two orders 

 of magnitude lower (Stoner et al., in press; Stoner 

 and Mehta, unpubl. data). High larval densities in 

 the Exuma Cays, particularly in the MFR, appear to 

 be directly associated with abundance of spawning 

 stocks. 



Appeldoorn, R. S., and L. Rodriquez. 1995. Department of 

 Marine Sciences, University of Puerto Rico, P.O. Box 908, 

 Lajas, Puerto Rico 00667. Unpubl. data. 



