Steller Sea Lion Research
Tracking Projects

The Steller Sea Lion Program has collected data on movement and diving behavior of sea lions since the early 1990s. Initial efforts focused on adult females tracked from rookeries in southeastern Alaska during 1992-1994. Results are reported in:

  • Rehberg, M. J., Andrews, R. D., Swain, U. G and Calkins, D. G. 2009. Foraging behavior of adult female Steller sea lions during the breeding season in Southeast Alaska. Marine Mammal Science 25(3): 588–604.

After management concern shifted from adults to immature sea lions, we began tracking sea lions between 2 months and 4 years of age (1998–2004) to better understand the development of diving and movement abilities of young sea lions and its potential implications during times of sparse or limited food supply. This expanded research effort was made possible by development of the dive capture technique. This work yielded several contributions to the literature:

  • Call, K.A., Fadely, B.S., Greig, A. and Rehberg, M.J. 2007. At-sea and on-shore cycles of juvenile Steller sea lions (Eumetopias jubatus) derived from satellite dive recorders: A comparison between declining and increasing populations. Deep Sea Research II. 54: 298–310.
  • Pitcher, K. W., Rehberg, M. J., Pendleton, G. W., Raum-Suryan, K. L., Gelatt, T. S., Swain, U. G., and Sigler, M. F. 2005. Ontogeny of dive performance in pup and juvenile Steller sea lions in Alaska. Canadian Journal of Zoology 83(9): 1214–1231.
  • Raum-Suryan, K. L., Rehberg, M. J., Pendleton, G. W., Pitcher, K.W., and Gelatt, T. S. 2004. Development of dispersal, movement patterns, and haul-out use by pup and juvenile Steller sea lions (Eumetopias jubatus) in Alaska. Marine Mammal Science 20(4): 823–850.
  • Sigler, M. F, Tollit, D. J., Vollenweider, J. J., Thedinga, J. F., Csepp, D. J., Womble, J. N., Wong, M. A., Rehberg, M. J. and Trites, A. J. 2009. Steller sea lion foraging response to seasonal changes in prey availability. Marine Ecology Progress Series 388: 243–261.

Because sea lions are difficult to recapture and can travel great distances after tagging, we primarily use tracking instruments that relay their results via satellite and thus do not require recovery. We attach instruments to sea lion fur using a cool-setting epoxy. Tags can remain attached to sea lions until the annual molt, which begins in late summer, at which time they are shed.

Contact the ADF&G Steller Sea Lion Program at