Aaibers and Sepulveda: Seasonal movement patterns and temperature profiles of adult Atractoscion nobilis off California 
13 
stock assessment with currently available data sources 
would better enhance our understanding of the popula- 
tion dynamics of this species and facilitate the develop- 
ment of long-term management strategies. 
In conclusion, this work provides insight into the 
seasonal movement patterns, habitat use, and depth 
distribution of wild-caught white seabass off the coast 
of California. Distinct seasonal depth distributions were 
identified with significantly deeper profiles during the 
winter months. Despite interannual variability, tagged 
adults spanned a narrow thermal gradient (13-16°C) 
centered around the 14°C isotherm, indicating the im- 
portance of environmental temperature on horizontal 
and vertical movements. A vertical shift to shallower 
waters during the spring and summer months directly 
coincides with the white seabass spawning period and 
with peak landings and fishing effort. Because of the 
diverse harvesting methods and seasonally high levels 
of fishing effort over a broad geographic range, all fish- 
eries must be considered for the effective management 
and long-term sustainability of this resource. 
Acknowledgments 
We thank T. Pfleger and family, the George T. Pfleger 
Foundation, the Catalina Seabass Fund, P. Offield, and 
the Offield Family Foundation for their generous sup- 
port. We appreciate donations from the San Diego Fish 
and Wildlife Commission, the Avalon Tuna Club, Oak- 
power Unlimited, and the Long Beach Neptunes. We 
also thank Captain T. Fullam, C. Heberer, M. Okihiro, 
B. Seiler, V. Wintrode, and K. Lafferty for assistance 
on various aspects of this work. We appreciate assis- 
tance and support from J. Albright and C. Albright, 
along with cooperation from all fishers that reported 
tag recovery information. We also thank J. Stopa for 
aid with graphic illustrations and J. Sepulveda for 
editorial support, in addition to valuable recommenda- 
tions by 3 anonymous reviewers. All experiments were 
performed under valid California Scientific Collection 
permit 002471. 
Literature cited 
Aaibers, S. A., G. M. Stutzer, and M. A. Drawbridge. 
2004. The effects of catch-and-release angling on the 
growth and survival of juvenile white seabass captured 
on offset circle and j-type hooks. N. Am. J. Fish. Man- 
age. 24:793-800. doi: 10.1577/M03-034.1. 
Aaibers, S. A. 
2008. Seasonal, diel, and lunar spawning periodicities 
and associated sound production management of the 
white seabass ( Cynoscion nobilis) in California waters. 
Fish. Bull. 106:143-151. 
Aaibers, S. A., and M. A. Drawbridge. 
2008. White seabass spawning behavior and sound 
production. Trans. Am. Fish. Soc. 137:542-550. doi: 
10.1577/T04-058.1. 
Aaibers, S. A., and C. A. Sepulveda. 
2012. The utility of a long-term acoustic recording sys- 
tem for detecting white seabass Atractoscion nobilis 
spawning sounds. J. Fish. Biol. 81:1859-1870. doi: 
10.111 1/j. 1095-8649. 2012. 03399.x. 
Allen, L. G., D. J. Pondella, and M. A. Shane. 
2007. Fisheries independent assessment of a returning 
fishery: abundance of juvenile white seabass (Atrac- 
toscion nobilis) in the shallow nearshore waters of 
the Southern California Bight, 1995-2005. Fish. Res. 
88:24-32. doi: 10.1016/j.fishres.2007.07.012. 
Baxter, J. L. 
1960. A study of the yellowtail Seriola dorsalis (Gill). 
Fish Bull. Calif. Dep. Fish Game 110:1-91. 
Bestley, S., T. A. Patterson, M. A. Hindell, and J. S. Gunn. 
2008. Feeding ecology of wild migratory tunas revealed by 
archival tag records of visceral warming. J. Anim. Ecol. 
77:1223-1233. doi: 10. 1111/j. 1365-2656. 2008. 01437.x. 
Cairns, J. L. 
1968. Thermocline strength fluctuations in coastal 
waters. J. Geophys. Res. 73:2591-2596. doi: 10.1029/ 
JB073i008p02591. 
Cairns, J. L., and E. O. LaFond. 
1966. Periodic motions of the seasonal thermocline 
along the southern California coast. J. Geophys. Res. 
71:3903-3915. doi: 10.1029/JZ071i016p03903. 
CDFG (Calif. Dep. Fish Game). 
2009. Review of selected California fisheries for 2008: 
coastal pelagic finfish, market squid, ocean salmon, 
groundfish, California spiny lobster, spot prawn, white 
seabass, kelp bass, thresher shark, skates and rays. Rel- 
iefs whelk, and sea cucumber. CalCOFI Rep. 50:14-42. 
2011. Review of selected California fisheries for 2010: 
coastal pelagic finfish, market squid, ocean salmon, 
groundfish, highly migratory species, Dungeness crab, 
spiny lobster, spot prawn. Reliefs whelk, and white sea- 
bass. CalCOFI Rep. 52:13-35. 
Clark, F. N. 
1930. Size at first maturity of the white seabass (Cy- 
noscion nobilis). Calif. Fish Game 16:319-323. 
Coykendall, D. R. 
1998. Population structure and dynamics of white 
seabass (Atractoscion nobilis) and the genetic ef- 
fect of hatchery supplementation on the wild popula- 
tion. Ph.D. diss., 106 p. Univ. Calif., Davis, CA. 
Danylchuk, S. E., A. J. Danylchuk, S. J. Cooke, T. L. Goldberg, 
J. Roppelman, and D. P. Phillip. 
2007. Effects of recreational angling on the post-release 
behavior and predation of bonefish (Albula uulpes ): 
the role of equilibrium status at the time of release. 
J. Exp. Mar. Biol. Ecol. 346:127-133. doi: 10.1016/j. 
jembe.2007.03.008. 
Franklin, M. P. 
1997. An investigation into the population structure of 
white seabass (Atractoscion nobilis), in California and 
Mexican waters using microsatellite DNA analysis. 
Ph.D. diss., 109 p. Univ. Calif., Santa Barbara, CA. 
Garcia-Reyes, M., and J. L. Largier. 
2012. Seasonality of coastal upwelling off central and 
northern California: new insights, including tempo- 
ral and spatial variability. J. Geophys. Res. 117, 
C03028. doi: 10.1029/2011JC007629. 
Gruenthal, R. M., and M. A. Drawbridge. 
2012. Toward responsible stock enhancement: broadcast 
spawning dynamics and adaptive genetic management 
