riverine, ascending the river following spawning. 

 Movements offish F 1 and F3 revealed that fish resid- 

 ing upstream during the summer will return to the 

 spawning grounds the following spring, and then 

 reascend the river after spawning. Factors respon- 

 sible for this behavior, quite different from that in 

 northern populations, are not positively known. 



Dudley et al. (1977) suggested temperature pre- 

 ference may be a reason for riverine behavior, and re- 

 cent studies by Coutant and Carroll (1980) and 

 Coutant et al. 3 further support this idea. Cooler, more 

 preferable temperatures are likely to be found up- 

 stream in the Savannah River in late spring and sum- 

 mer. In late May 1980 the temperature at km 30 1 was 

 16°C, while the river temperature at Savannah (km 

 35) was 24°C. Four striped bass were found up- 

 stream on 28 and 29 May in waters of between 16° 

 and 19°C. While Coutant and Carroll (1980) found 

 that small (3.1 kg) striped bass preferred tem- 

 peratures of 20°-24°C, striped bass of 5 kg or greater 

 preferred temperatures of 16°-22°C (Coutant et al. 

 footnote 3). All our tagged fish exceeded 5 kg. Both 

 Orsi (1971), working in California, and Nichols and 

 Miller (1967), working in Chesapeake Bay, found 

 that larger striped bass were more likely to move to 

 cooler ocean waters. 



Available evidence suggests that striped bass use 

 the saline portions of the Savannah River estuary and 

 adjacent waters during the winter. Of five fish known 

 to have working transmitters during the winter, only 

 one could be regularly located and it was in saline 

 water. The other four could not be found in 

 freshwater or saline reaches of the river. These fish 

 likely moved to nearby marine or estuarine waters 

 during January and February. Fish known to be in the 

 river in summer had already departed by October. 



Although our tagged fish probably inhabited the 

 lower estuary or marine waters during the winter of 

 1980, Savannah River striped bass sometimes re- 

 main in areas 250-330 km from the river mouth dur- 

 ing the winter (Dudley et al. 1977). The differences in 

 these findings could reflect variations among in- 

 dividual fish or among years, caused, perhaps, by 

 winter temperature or flow regimes. The small num- 

 ber of fish tagged during the winter precludes inves- 

 tigating this problem, but observations made during 

 attempts to collect striped bass suggest that year-to- 

 year variations in wintering areas do occur. In some 

 years (e.g., 1974) large striped bass were commonly 

 sighted in upstream areas (Dudley et al. 1977). In 



other years (1979, 1980) none were seen there in 

 spite of intensive efforts to collect them. 



Acknowledgments 



Many thanks are extended to field personnel K. Ed- 

 wards, J. Hatcher, D. Goodrum, W. Butler, D. 

 Goldbaugh, and K. Black, and to others who helped 

 with the project. Special thanks go to State of 

 Georgia personnel who contributed their time and 

 expertise, especially R. Rees, C. Hall, W. Vallentine, 

 M. Shell, and L. Bryan. Thanks also are due L. Mc- 

 Swain, Assistant Chief of the State of Georgia 

 Fisheries Division, and L. Villanova of the U.S. Fish 

 and Wildlife Service, Federal Aid Office in Atlanta. 

 R. Reinert and R. Gilbert also provided helpful assis- 

 tance. This research was funded by the U.S. Fish and 

 Wildlife Service via the Anadromous Fish Conserva- 

 tion Act (P.L. 89-304) and by the School of Forest 

 Resources, University of Georgia. 



Literature Cited 



Coutant, C. C, and D. S. Carroll. 



1980. Temperatures occupied by ten ultrasonic- tagged 

 striped bass in freshwater lakes. Trans. Am. Fish. Soc. 

 109:195-202. 

 Dudley, R. G., and K. N. Black. 



1978. Distribution of striped bass eggs and larvae in the 

 Savannah River estuary. Proc. Annu. Conf. Southeast. 

 Assoc. Fish Wildl. Agencies 32:561-570. 

 Dudley, R. G., A. W. Mullis, and J. W. Terrell. 



1977. Movements of adult striped bass in the Savannah 

 River, Georgia. Trans. Am. Fish. Soc. 106:314-322. 

 Nichols, P. R., and R. V. Miller. 



1967. Seasonal movements of striped bass Roccus saxatilis 

 (Walbaum) tagged and released in the Potomac River, 

 Maryland, 1959-61. Chesapeake Sci. 8:102-124. 

 Orsi, J. J. 



1971. The 1965-67 migrations of the Sacramento-San 

 Joaquin estuary striped bass population. Calif. Fish Game 

 57:257-267. 



Richard G. Dudley 



School of Forest Resources 



University of Georgia, Athens, GA 30601 



Present address: Department of Fisheries and Wildlife 



Oregon State University, Corvallis, OR 97331 



T. Glenn McGahee 



School of Forest Resources 



University of Georgia 



Athens, GA 30601 



Present address: Southeastern Wildlife Services 



119 Hoyt Street, Athens, GA 30613 





'Coutant, C.C..H.R. Waddle, and B. A. Schaich. 1980. Tempera- 

 ture and habitat selection by striped bass. Underwater Telem. 

 Newsletter 10(1): 1-4. Available from Environmental Sciences 

 Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830. 



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