12 



Fishery Bulletin 93(1), 1995 



40" 



38 



■£ 36 ' 



34" 



30' 



132' 



120' 



118' 



Longitude 



Figure 6 



Locations of on-effort sightings of beaked whales of the genus Mesoplo- 

 don (...), Cuvier's beaked whales (O), Baird's beaked whales ( ), and 

 unidentified beaked whales (x). Scientific names are given in Table 1. 



model by minimizing AIC would have been too time 

 consuming to include in the bootstrap procedure; 

 hence, precision estimates are contingent on the cho- 

 sen models being approximately correct. Variability 

 in estimating mean group size was included implic- 

 itly in the Monte Carlo sampling, but it was assumed 

 that the group size estimate for any given group was 

 accurate. Pooling of data to estimate /10) and g(0) 

 introduces a bias (to the extent that individuals dif- 

 fer within a pooled group) which is not accounted for 

 in precision estimates. All of these factors would tend 

 to result in precision being overestimated. Overall, 

 coefficients of variation are likely to be too small and 

 true confidence intervals are probably wider than 

 those reported. 



Acknowledgments 



This survey could not have been accomplished with- 

 out the diligent work of many people, including the 

 officers and crew of the RV McArthur. S. Hill served 

 as cruise coordinator. The six primary observers were 

 W. Armstrong, S. Benson, J. Cotton, D. Everhardt, 

 M. Lycan, and R. Mellon. The independent observ- 



ers included E. Archer, K. Forney, S. Hill, S. 

 Kruse, M. Lowry, V. Philbrick, B. Taylor, and 

 P. Wade (and J. B.). The ship-board data log- 

 ging software was written by J. Cubbage (and 

 J. B.). Observer training was provided by S. 

 Hill, A. Jackson, W. Perryman, and R. Pit- 

 man. Data were edited and archived by A. 

 Jackson and K. Wallace. Sighting distribu- 

 tions were plotted with software written by 

 T Gerrodette. The survey design was im- 

 proved by thoughtful suggestions from T 

 Gerrodette and D. DeMaster. This manu- 

 script was improved by helpful suggestions 

 from S. Buckland, K. Burnham, J. Calam- 

 bokidis, J. Carretta, K. Forney, T Gerrodette, 

 J. Laake, R. Brownell, P. Wade, and two 

 anonymous reviewers. 



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