Perrin et al.: Geographic variation in cranial morphology of Stenella attenuata 



345 



nificantly in some regard from those south of 5°N 

 and should be managed separately (yielding three 

 management units instead of the present two). Cer- 

 tainly, the specimens from the Hawaiian Islands are 

 generally larger than those from the south, south- 

 west, and west with which they have their closest 

 morphologic affinity. 



Note added in proof Based in part on the results 

 and recommendations in this paper, the manage- 

 ment unit boundaries for the offshore spotted dol- 

 phin in the eastern Pacific have been changed. The 

 boundary of a new "Northeastern stock" runs south 

 along the 120°W meridian to 5°N and then east to 

 the mainland. Offshore spotted dolphins outside this 

 zone to the west and south are now part of a "West- 

 ern/Southern stock." February, 1994. 



Acknowledgments 



Support for aspects of this research was received by 

 the University of Oklahoma through Contract 

 79-ABC-00167 from the U.S. Department of Com- 

 merce, National Oceanographic and Atmospheric 

 Administration, and Purchase Orders 84-ABA- 

 02177 and 40JGNF0532 from the National Marine 

 Fisheries Service, Southwest Fisheries Science Cen- 

 ter, La Jolla, CA. We thank individuals (listed in 

 Douglas et al., 1992) who provided access to mu- 

 seum specimens. M. E. Douglas measured the ini- 

 tial set of specimens used in this study. Pamela A. 

 Pogorelc assisted with preparation of some of the 

 figures. Paul Fiedler, Steven Reilly, Michael Scott, 

 and an anonymous reviewer provided useful sugges- 

 tions on earlier drafts of this paper. 



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