Simms et al.: Distribution, growth, and mortality of larval Istiophorus platypterus in the northern Gulf of Mexico 
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Hatch date (month/day) 
Figure 7 
Hatch-date distribution of sailfish (Istiophorus platypterus ) larvae collected 
from the northern Gulf of Mexico in 2005 (n=1037) and 2006 Cm. = 1317 ) (gray 
bars). Larvae were pooled and arranged by month and day. Hatch dates were 
determined by subtracting age from catch date. Otolith-derived ages were used 
when available; remaining ages were predicted by applying age-length key. The 
mortality-adjusted hatch-date distribution as a percentage of hatching events 
per day (solid line) is also shown. 
Acknowledgments 
This work was supported by the McDaniel Charitable 
Foundation, the National Oceanic and Atmospheric 
Administration, and the Oceanic Conservation Organiza- 
tion. We thank J. Alvarado Bremer, T. Potter, C. Pratt, 
B. Saxton, T. Tidwell, and others for assistance in the 
field and in the laboratory. J. Magnussen and M. Shivji 
of Nova Southeastern University provided the genetic 
identification protocol, and J. Graves and J. McDowell 
of the Virginia Institute of Marine Science provided 
training in identification of larvae. This work would not 
have been possible without the support of J. Heldt who 
provided the boat time. A. Anis, A. Armitage, and D. 
Wells provided comments on the manuscript. 
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