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Fishery Bulletin 96(4), 1 998 
crabs and certain polychaetes (Ray-Culp et al., 1997). 
Queen conch <50 mm shell length have rarely been 
encountered in the field (Iversen et al., 1994; Ray 
and Stoner, 1995; Iversen and Jory, 1997), and the 
only density data extant for these small conch were 
collected by Sandt and Stoner (1993) near Lee Stock- 
ing Island, Bahamas. However, queen conch settle 
at a large size (1.2 mm), compared with many other 
mollusks, and even the smallest juvenile, unless 
crushed completely, leaves an identifiable shell record 
of its settlement in the sediment (our study). This record 
can be used to examine the settlement-recruitment 
relationship and spatial variation in settlement. 
Our study had three primary objectives. First, we 
conducted an extensive dredge survey for newly 
settled queen conch in and around a well-studied 
nursery area in the central Bahamas during the sum- 
mer recruitment season in 1992. The survey was 
designed to test the hypothesis that the long-term 
distribution pattern of year-class 1 and 2 conch was 
associated with settlement pattern. The sum of live 
and dead individuals was used as an index of settle- 
ment at each sampling station, and the number of 
surviving (live) conch served as an index of recruit- 
ment. Through this survey, we gathered the first 
quantitative data on the distribution of queen conch 
<45 mm shell length (1.5-44 mm). Second, we used 
observations of shell damage sustained by dead in- 
dividuals to determine the primary predatory forms 
on newly settled queen conch. We also examined spa- 
tial variation in predation type. Third, we examined 
the effects of environmental characteristics, such as 
depth, sediments, macrophytes, older conspecifics, 
and distribution of potential predators, on the ob- 
served distribution of newly settled queen conch. 
Study area 
The Exuma Cays are an important source of queen 
conch for a large fishery in the Bahamas; the island 
chain is 250 km long, bordered to the east by the 
Exuma Sound, and to the west by the Great Bahama 
Bank. Water exchange occurs through numerous 
tidal inlets separating the islands, creating exten- 
sive tidal flow fields on the shallow bank. Nurseries 
of juvenile conch (1- and 2-yr-old, 70-150 mm SL) 
are located primarily on the bank side of the Exuma 
Cays near these inlets and are typically associated 
with seagrass meadows (2-4 m deep) that are flushed 
with clear, oligotrophic water from the Sound dur- 
ing flood tide (Stoner et al., 1996b). 
We elected to survey postlarval conch in a tidal 
flow field located west of Lee Stocking Island and 
south of Norman’s Pond Cay because the conch nurs- 
ery near Shark Rock (Fig. 1) is well studied. Prior to 
sampling, five years of data had been collected on 
the distribution and abundance of 1- and 2-year-old 
juvenile conch, and environmental characteristics 
such as seagrass biomass, depth, and tidal currents 
had been mapped (Jones, 1996; Stoner et al., 1996b). 
Drogue studies have shown that, on flood tide, wa- 
ter from the Sound enters the inlet north of Lee Stock- 
ing Island, passes close to Shark Rock, and flows west 
of the nursery for a distance that is dependent on 
wind conditions and tidal phase (e.g. spring, neap) 
(Stoner et al., 1994). Tidal currents, which reach 100 
cm/s at midtide, flow between sand bars in an S-shaped 
pattern following the bank bathymetry (Fig. IB). The 
middle of the tidal channel is ~3 m deep and veg- 
etated primarily with the seagrass Thalassia 
testudinum. Depth and seagrass density gradually 
decrease from midchannel to bare sand on both sides 
of the channel. Tidal range is ~1 m. 
Annual surveys conducted between 1988 and 1992 
showed that aggregations of juvenile queen conch 
always grazed within a 2-km long section of the tidal 
flow field close to Shark Rock (Fig. 1) and, at any 
given time, occupied only portions of the suitable 
habitat available (Stoner et al., 1996b). Stations for 
this study were established with reference to long- 
term distribution of conch in this area (Stoner and 
Waite, 1990; Stoner and Ray, 1993; Ray and Stoner, 
1994) and to represent both down-channel and across- 
channel dimensions of the flow field. One line of sta- 
tions was established in midchannel down the flow 
field from Adderly Cay (A) to Cook’s Cay (F) with an 
attempt to locate all of the stations in similar depth 
and moderate seagrass shoot density. Stations A and 
F were each located ~4 km from the geographic center 
of the traditional nursery ground (Fig. 1), and stations 
B and E were located -250 m outside the northeastern 
and southwestern ends of the nursery, respectively. 
Stations C3 and D3 were each established -500 m from 
the geographic center of the nursery (Fig. 1C). 
To represent the across-flow field dimension, five 
more stations were selected along two transects that 
lay perpendicular to the main axis of the tidal cur- 
rent at stations C3 and D3, as well as across the 
seagrass gradient. Thalassia testudinum density 
ranged from 4 to 704 shoots/m 2 and from 0.5 to 178 g 
dry wt/m 2 across this gradient in 1991 (Ray and 
Stoner, 1994) (Fig. 1C). Three stations were estab- 
lished along the D transect in addition to D3, increas- 
ing in macrophyte cover from bare sand at D1 to high 
seagrass and detrital biomass at D4. Along transect 
C, two stations were established in addition to C3, 
ranging from sand to moderate seagrass shoot den- 
sity and macrophyte biomass. There were no areas 
of high seagrass biomass present near transect C and, 
