216 
Fishery Bulletin 108(2) 
are on the horizon. These fishery-dependent data can 
now be compared directly with fishery-independent sur- 
vey data, creating two independent lines of evidence for 
management strategies. Specific catch data may also 
be used to identify areas in which the most vulnerable 
species may be most heavily impacted and thus can 
help identify areas in which restrictions or closures 
are necessary. Although observer data do not give a 
complete account of skate bycatch in the fisheries of 
Alaska, the information currently provided allows this 
diverse assemblage of species to be managed in a more 
biologically appropriate way than was possible in the 
past. As fishing pressure on Alaska’s skate populations 
increases, the consequences of data deficiencies will be 
magnified, and observer data will play an increasingly 
important role in protecting skates from the declines in 
biomass and shifts in community structure that have 
befallen these fishes in other parts of the world. 
Acknowledgments 
We thank the multitude of staff and observers of the 
North Pacific Groundfish Observer Program that have 
helped to collect the data used here. We also thank S. 
Gaichas, O. Ormseth, and B. Matta for discussions about 
skate stock assessments, R. Narita for assistance with 
data retrieval, and T. Hiatt for providing skate price 
information. For comments on an early draft of the 
manuscript, we thank M. Loefflad, B. Mason, B. Matta, 
P. Nelson, O. Ormseth, and J. Orr. 
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