Graham et al : Prosomal-width-to-weight relationships for Limulus polyphemus 
243 
to collect data on the average PW of female and male 
horseshoe crabs to fine tune these conversion factors. 
The PW-equations derived from this study can be used 
to estimate weight based on an average prosomal width. 
In this way, the accuracy of these conversion factors 
could be improved, thereby providing better data for 
future management assessments. 
Acknowledgments 
We sincerely thank S. Michels, M. Beekey, and J. Mattei 
for generously providing unpublished data on horse- 
shoe crab populations from Delaware and Connecticut 
(listed in Table 1), and B. Spear for his contributions 
to this manuscript. J. Brust, R. Burgess, L. DeLancey, 
S. Doctor, S. Gerhart, L. Gillingham, P. Himchak, A. 
Leschen, C. McBane, T. Moore, M. Oates, S. Olszewski, 
and P. Thayer provided valuable information about state 
conversion factors. We also thank M. Davis, M. Duncan, 
R. Leaf, B. Ray, and A. Villamagna for their assistance 
with data analyses, manuscript reviews, and discussion 
of research ideas. 
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