McElroy et al.: Comparison of length distributions from a longline survey and a trawl survey for 2 groundfish species 241 
in the BTS. It remains to be determined if other factors 
could influence the gear selectivity or availability of large 
cod; however, the results of analysis in this study support 
the continued use of the asymptotic (flat-topped) selectiv- 
ity for the BTS in the GOM cod stock assessment. 
Acknowledgments 
We thank captains P. Lynch (F/V Mary Elizabeth) and 
E. Hesse (F/V Tenacious IT) and their crews for contributions 
to the LLS. We thank the NEFSC Cooperative Research 
Branch staff, particularly C. Alexander, B. Gervelis, 
G. Gianesin, and D. St. Amand, for their support of the LLS. 
Special thanks to L. O’Brien, M. Martin, and P. Rago for con- 
tributions to the design of the LLS. We are grateful to staff of 
the NEFSC Ecosystems Surveys Branch for tireless efforts 
on the BTS. Thanks to A. Wood and P. Politis for comments 
on an earlier draft. 
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