346 
Fishery Bulletin 116(3-4) 
The spatial disjunction of squatinid sharks between 
the EC and the GOM suggests the possibility of genetic 
isolation between angel sharks in the 2 regions. There¬ 
fore, we hypothesize that squatinid sharks in the GOM 
and the EC are separate evolutionary units. Although 
current research cannot address the species status of 
squatinid sharks in US waters of the WNA, our find¬ 
ings do suggest an evaluation is warranted. Further, 
on the basis of the presence of what appears to be a 
distributional break at the Mississippi River Delta/Mis¬ 
sissippi Canyon, we hypothesize that squatinids in the 
eastern and western GOM represent, at a minimum, 2 
separate populations. As human activities intensify in 
offshore waters of the GOM (e.g., commercial fishing, 
petroleum industry), it will become increasingly imper¬ 
ative to understand the species composition and popu¬ 
lation structures of marine organisms in poorly studied 
areas so that conservation efforts can effectively miti¬ 
gate potentially deleterious effects. 
Acknowledgments 
We thank J. Gartland (Virginia Institute of Marine 
Science), R. Hart (NMFS), R Kostovick (NMFS), and 
T. Smart (South Carolina Department of Natural Re¬ 
sources) for providing data from various surveys. We 
also thank the numerous persons who spent an ex¬ 
traordinary amount of time at sea collecting the data 
used in our study. 
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