Bengtson et al,: Comparison of survey methods for estimating abundance of Phoca vitulina 



355 



Acknowledgments 



L. Dzinich, O. Harding, K. Blejwas, and N. Tex pro- 

 vided field assistance with shore-based counts at Johns 

 Hopkins Inlet. Funding for this project was provided by 

 the National Park Service to E. A. Mathews and J. L. 

 Bengtson and by the National Oceanic and Atmospheric 

 Administration and the National Park Service to J. L. 

 Bengtson. We thank M. Kralovec and M. B. Moss at the 

 Glacier Bay National Park for their support in helping to 

 secure funding. S. Slade at Leica GeoSystems provided 

 technical assistance for Erdas Imagine for the aerial 

 photography counts. S. Tackley produced Figures 2 and 

 3. This manuscript was improved by comments from J. 

 K. Jansen, J. M. Waite, and three anonymous reviewers. 

 This research was conducted under Marine Mammal 

 Protection Act permits 527-1461, 782-1355, and 782-1676. 



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