Current address: Nicholas School of the Environment, Duke University, PO Box 90328, Durham, North Carolina 27708, U.S.A.
Effects of research disturbance on the behavior and abundance of Steller sea lions (Eumetopias jubatus) at two rookeries in Alaska
Article first published online: 15 JUN 2011
© 2011 by the Society for Marine Mammalogy
Marine Mammal Science
Volume 28, Issue 1, pages E58–E74, January 2012
How to Cite
Wilson, K., Fritz, L., Kunisch, E., Chumbley, K. and Johnson, D. (2012), Effects of research disturbance on the behavior and abundance of Steller sea lions (Eumetopias jubatus) at two rookeries in Alaska. Marine Mammal Science, 28: E58–E74. doi: 10.1111/j.1748-7692.2011.00485.x
- Issue published online: 28 DEC 2011
- Article first published online: 15 JUN 2011
- Received: 18 June 2009, Accepted: 18 February 2011
- Steller sea lion;
- Eumetopias jubatus;
We examined the effects of research disturbance on the behavior and abundance of Steller sea lions (Eumetopias jubatus) at rookeries on Marmot and Ugamak Islands in Alaska. During 3 of 6 yr, researchers intentionally drove all adult and juvenile sea lions off at least part of the beach in order to permanently mark and measure sea lion pups. The research disturbance occurred after the majority of females had bred and when most pups were 1 mo old. We used generalized linear models to determine the relationship between research disturbance and sea lion behavior or abundance. Research disturbance was related to changes in the proportion of sea lions exhibiting two to three of nine behavior metrics: agonistic and resting females and active males at Marmot, and active and resting males and females at Ugamak. Model results indicated that changes lasted between 3 and 20 d depending on the sex, behavior, and rookery. Inclusion of research disturbance into Marmot abundance models did not improve the fit to the data, if variability between years was permitted. Optimally timed, low-frequency research disturbance did not appear to have long-term effects on sea lion behavior or abundance and was largely associated with changes that were similar to natural variation.