Adult Queen Conch 



Horseshoe Reef, Lee Stocking Island 



Adult queen conch in the Exuma Cays are now only found in 

 relatively deep water ( >6 m), generally in channels with high 

 concentrations of Thalassia and offshore on sand and relic coral 

 reef outcroppings. 



The most significant adult population in the Lee Stocking 

 Island area is an offshore spawning stock found at a depth of 15- 

 23 m on the Exuma Sound side of the Island and ranging in size 

 from 17.7-26.8 cm. They are found mainly during late spring 

 through early fall on carbonate sand bottom partially covered by 

 a thin algal mat adjacent to a deepwater reef (Horseshoe Reef) 

 running parallel to, and about 1/2 mile from, the beach. This 

 reef, with a steep vertical profile of about 5m, is a barrier 

 which prevents the conch from moving further inshore. During 

 the winter months most of the offshore group have been observed 

 on top of relic patch reefs. These large mounds have little 

 living hard coral but are covered by algae and soft corals. The 

 algae most likely provide food to the conch during the winter. 

 During August 1987 some individuals remained on the offshore 

 mounds (Allan Stoner, CMRC, pers. comm.). We believe that a 

 sizeable portion of the Children's Bay Cay, Tugboat Cay and other 

 nursery conch populations in the area are recruited from the 

 offshore spawning groups. The depth of the offshore conch 

 population protects them from most fishing pressure allowing 

 their numbers to remain constant and ensuring spawning success. 



Studies of conch by other investigators indicate that their 

 spawning season ranges from March to September (Randall 1964; 

 D'Asaro 1965; Brownell 1977) and that they migrate offshore in 

 the winter (Randall 1964; Hesse 1979). We observed spawning 

 behavior in this deepwater population on the sand bottom 

 throughout spring and summer in 1985, 1986, and 1987. One small 

 shallow water (<5 m) spawning group was also observed near the 

 eastern shore of Norman's Pond Cay in July 1987. 



In summary, the area around Lee Stocking Island is a major 

 nursery ground for juvenile S^ gigas and an excellent site for 

 research on the species. We suggest that this site be the focus 

 of future research concentrating on the following: 1) recruitment 

 of young into the nursery areas, 2) description of factors 

 necessary for the survival of the youngest conch, 3) predation, 

 and 4) food availability. 



ACKNOWLEDGMENTS 



This research was supported by the Office of Undersea 

 Research, National Oceanic and Atmospheric Administration, U.S. 



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