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Fishery Bulletin 106(3) 
94°0’0"W 92WW 90°0'0"W 88WW 86”0'0"W 
The locations of the shipwreck sites surveyed in the Gulf of Mexico with the XL-11 ROV. Red deepsea 
crabs ( Chaceon quinquedens ) were found at the four deeper sites (Gulf Penn, U-166, Robert E. Lee, and 
Alcoa Puritan). 
in the Mississippi Canyon or adjacent areas (Fig. 1) and 
varied in water depth from 90 to 1970 m. At each wreck, 
ROV transects were conducted over the wreck and over 
the debris field. Once transects were completed, traps 
were set and biological sampling with the ROV began. 
Transects over the wreck and in parallel lines adjacent 
to the wreck until about 300 m were mapped before the 
deployment of the ROV. The ROV and trap sampling 
time lasted a minimum of eight hours and a maximum 
of sixteen hours. At each wreck, both a small baitfish 
trap (95 cm width x 75 cm length x 50 cm height) and a 
chevron fish trap (150 cm width x 180 cm lengthx60 cm 
height) baited with herring and squid were set within a 
few meters of the wreck and approximately 300 m away 
from the wreck. A baited crab trap (64 cm width x 97 
cm length x 51 cm height) was placed near the wreck, 
and two minnow traps (23 cm diameter x 44 cm length) 
bound together were placed far from the wreck; both 
were baited with canned cat food and biolume sticks. 
Additional collections were made at the direction of 
biologists using the manipulator arm of the ROV for 
larger invertebrate specimens and the suction hose of 
the ROV (approximately 10 cm in diameter) for smaller 
invertebrate specimens. 
Each crab specimen collected was measured from the 
anterolateral spine on one side of the carapace to the 
anterolateral spine on the opposite side for carapace 
width (CW) to the nearest 0.1 mm with vernier calipers. 
Shell condition and missing appendages were noted and 
sex was recorded. If the crab was female, presence and 
color of eggs were also recorded. Voucher specimens 
from each wreck were either preserved in 90% ethanol 
or frozen. 
Statistical analyses were performed with SPSS 14.0 
( SPSS, Inc., Chicago, IL) software to determine if crab 
size or sex was related to the distribution of the crabs. 
To determine if there was a correlation with size and 
depth, a linear regression was performed with a 95% 
confidence interval. To examine the relationship of sex 
with depth, the Kruskal-Wallis test was used because 
the data were non-normal. Data were also non-normal 
for depth distribution, but linear regression was used 
to determine if a linear correlation existed. 
Results 
Chaceon quinquedens was found at the four deepest of 
the six shipwrecks, and there was no linear distribu- 
tion of the crabs by sex. A total of 127 specimens was 
collected at the four sites, with CW ranging from 21.2 
mm to 141.1 mm (Table 1). No significant correlation 
occurred between depth and crab size (R 2 - 0.051). The 
smallest crabs were found at the shallowest depth, and 
