ESR 10:93-106 (2009)  -  doi:10.3354/esr00239

Behavioural estimation of blue whale movements in the Northeast Pacific from state-space model analysis of satellite tracks

Helen Bailey1,*,**, Bruce R. Mate2,**, Daniel M. Palacios1,3, Ladd Irvine2, Steven J. Bograd1, Daniel P. Costa4

1NOAA/NMFS/SWFSC/Environmental Research Division, 1352 Lighthouse Avenue, Pacific Grove, California 93950, USA
2Marine Mammal Institute, Department of Fisheries and Wildlife, and Coastal Oregon Marine Experiment Station, Oregon State University, Hatfield Marine Science Center, 2030 SE Marine Science Drive, Newport, Oregon 97365, USA
3Joint Institute for Marine and Atmospheric Research, University of Hawaii at Manoa, 1000 Pope Road, Marine Science Building 312, Honolulu, Hawaii 96822, USA
4Ecology and Evolutionary Biology, Long Marine Laboratory, University of California, Santa Cruz, 100 Shaffer Road, Santa Cruz, California 95060, USA
*Email: **Both authors contributed equally to this work

ABSTRACT: Baleen whale migrations typically consist of annual movements between productive, high-latitude feeding grounds and unproductive, low-latitude breeding grounds. However, the actual migratory path and whales’ behaviour in these locations are poorly known. The objectives of this study were to apply a switching state-space model to the satellite tracks of blue whales Balaenoptera musculus in the Northeast Pacific to improve location estimation and gain insight into the migratory (transiting) and foraging (area-restricted search, ARS) behaviours of this population. During the period 1993 to 2007, Argos satellite tags were attached to 159 whales, mainly off the coast of California during late summer, of which 92 tracks were >7 d in duration. There was generally a southward movement during the winter to Baja California and to an area west of the Costa Rica Dome, in the eastern tropical Pacific (ETP). Travel speeds during transit were significantly faster than during ARS movements (mean = 3.70 and 1.05 km h–1, respectively). On average, 29% of the track time was spent in ARS, and the mean time within an ARS patch was 21 d. The occurrence of ARS behaviour throughout the migration cycle suggests that these animals may forage year-round, but could also indicate limited movements during the reproductive season. The extent of their northward migration from Baja California to Washington varied significantly interannually, likely in response to environmental changes affecting their prey. The long track durations obtained from electronic tagging have provided essential new information about the critical habitats of Northeast Pacific blue whales.


KEY WORDS: Balaenoptera musculus · Satellite telemetry · Area-restricted search · Migration · First-passage time · Foraging · Baja California · Eastern tropical Pacific


Full text in pdf format  
Cite this article as: Bailey H, Mate BR, Palacios DM, Irvine L, Bograd SJ, Costa DP (2009) Behavioural estimation of blue whale movements in the Northeast Pacific from state-space model analysis of satellite tracks. Endang Species Res 10:93-106

Export citation: Endnote - Reference Manager
Mail this link - Contents Mailing Lists - RSS
- -