eled In 24 hours as 185 kni. Pike 

 (1962) used the same calculations to 

 determine that northward migrants 

 traveled from 56-80 km/day at about 

 Vi-'/i the rate of southern migrants. 



During this study, natural markings 

 on three whales observed on successive 

 days permitted the calculation of 

 speeds of movement along two areas 

 of the coastline. Rates of movement 

 of all 3 are comparable to Pike's 

 calculations. 



Two 12-1.^ meter individuals, one 

 distinctly marked with white brush 

 markings on the tail stock and flukes, 

 were seen 11. 12. and 13 April 1972. 

 During the 49.5 hours between the 

 first and third sightings, they moved 

 approximately 129 km from the 

 Coronado Islands to near .San Cle- 

 mente. Calif., an average speed of 

 only 2.6 km/hour. 



A 12-meter individual with a nearly 

 all white tail fluke and a wide white 

 band across the tail stock was seen 

 with four other animals off Point 

 La Jolla on 27 March 1972. The 

 same animal was observed again on 

 the 28th just northwest of Newport 

 Beach and on the 29th 13 km south- 

 west of Point Vincente. Net movement 

 in 44 hours was 128 km or 2.9 km/ 

 hour. 



Finally, an unusually dark yearling 

 observed just south of Point .San Luis 

 27 April 1972 had moved 64 km to 

 the north when it was resighted 23 

 hours later northwest of Point Estero. 

 It had moved at an average rate of 

 2.8 km/hour. 



SUMMARY 



Results of periodic aerial surveys 

 are comparable to those from ship 

 and land-based surveys in defining 

 the timing of migration of gray whale 

 populations past southern California. 

 Peak densities were observed in Janu- 

 ary for the southward and in March 

 for the northward migration. Over 

 half the population observed passed 

 more than 64 km offshore from San 

 Diego. Cows with calves were seen 

 from February through May primar- 

 ily inshore and tended to be alone or 

 with other cows with calves. Yearling 

 whales were seen inshore from Feb- 

 ruary through April and tended to be 

 solitary or with other yearlings. Fi- 

 nally, average speeds observed for 

 three individuals over small segments 

 of the northward migration route 

 were comparable to estimates based 

 on peak movements past shore stations. 



ACKNOWLEDGMENTS 



I am indebted to many people for 

 help with this project. John Hall and 

 Larry Tsunoda each flew some of the 

 survey flights. George Lingle and 

 John Moore helped summarize the 

 data. Raymond Gilmore. Dale W. 

 Rice, and William F. Perrin read the 

 manuscript and made useful sugges- 

 tions. Marita Doerflein. Marty Allen, 

 and Shirlee Preis typed the manu- 

 script. 



Finally. I am indebted to the officers 

 and men of Carrier Antisubmarine 

 Air Groups 53 and 59 for their skill, 

 patience and helpful spirit, and to 

 LCDR Al Zollers for scheduling air- 

 craft. 



This research was part of NUC IR 

 Project 150550 "Marine Mammal 

 Populations," W. E. Evans principal 

 investigator. 



LITERATURE CITED 



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Evans. W. E. 1972. A mobile maruie en- 

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Evans, W. E., and J. S. Lealherwood. 1972. 

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1:9-20. 



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MFR Paper 1055. From Marine Fisheries Review, Vol. 

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