02299nas a2200253   4500008004100000245010500041210006900146300001400215490000700229520153000236653002401766653001401790653001501804653000701819653001101826100002801837700002101865700002501886700002301911700002001934700002001954700002201974856004901996       2004                        eng d00aAcoustic and satellite remote sensing of blue whale seasonality and habitat in the Northeast Pacific0 aAcoustic and satellite remote sensing of blue whale seasonality   a967–9860 v513 aNortheast Pacific blue whales seasonally migrate, ranging from the waters off Central America to the Gulf of Alaska. Using acoustic and satellite remote sensing, we have continuously monitored the acoustic activity and habitat of blue whales during 1994-2000. Calling blue whales primarily aggregate off the coast of southern and central California in the late summer, coinciding with the timing of the peak euphausiid biomass, their preferred prey. The northward bloom of primary production along the coast and subsequent northbound movements of the blue whales are apparent in the satellite and acoustic records, respectively, with the calling blue whales moving north along the Oregon and Washington coasts to a secondary foraging area with high primary productivity off Vancouver Island in the late fall. El Nio conditions, indicated by elevated sea-surface temperature and depressed regional chlorophyll-a concentrations, are apparent in the satellite records, particularly in the Southern California Bight during 1997/1998. These conditions disrupt biological production and alter the presence of calling blue whales in primary feeding locations. Remote sensing using acoustics is well suited to characterizing the seasonal movements and relative abundance of the northeast Pacific blue whales, and remote sensing using satellites allows for monitoring their habitat. These technologies are invaluable because of their ability to provide continuous large-scale spatial and temporal coverage of the blue whale migration.10aacoustic-monitoring10amigration10amonitoring10ars10awhales1 aBurtenshaw, Jessica, C.1 aOleson, Erin, M.1 aHildebrand, John, A.1 aMcdonald, Mark, A.1 aAndrew, Rex, K.1 aHowe, Bruce, M.1 aMercer, James, A.  uhttp://dx.doi.org/10.1016/j.dsr2.2004.06.020