Movements and Area Use of Belugas in a Subarctic Alaskan Estuary
In this study, scientists monitored the movements of belugas tagged in Cook Inlet in mid to late summer during the years 2000 to 2002 and used the satellite telemetry data to define wintering areas and examine monthly patterns of area use.
Seasonal movements of 14 belugas in Cook Inlet, Alaska were monitored by satellite telemetry between July and March in 2000–2003. Whales used waters in the upper Cook Inlet intensively between summer and late autumn and dispersed to mid-inlet offshore waters during winter months. All whales remained in Cook Inlet the entire time they were tracked, and several whales were tracked through March. During summer and early fall, movements were clearly concentrated in specific areas, generally river mouths or bays, where whales were likely feeding on fish runs. Average daily travel distances ranged from 11 to 30 km per day. monthly home ranges, estimated using the 95 percent kernel probability distribution of average daily positions, were smallest in August (982 km2), increased throughout autumn, and peaked in winter (reaching approximately 5000 km2). The seasonal variation in distribution and movement patterns displayed by belugas in Cook Inlet affect the sighting rates and seasonal abundances estimates obtained for this depleted population.
R.C. Hobbs, K.L. Laidre, D.J. Vos, B.A. Mahoney, and M. Eagleton. Published in Arctic, Vol. 58, No. 4 (December 2005).