#rp188

Fish-eating ‘‘resident’’-type killer whales ~Orcinus orca! that frequent the coastal waters off northeastern Vancouver Island, Canada have a strong preference for chinook salmon. The whales in this region often forage along steep cliffs that extend into the water, echolocating their prey. Echolocation signals of resident killer whales were measured with a four-hydrophone symmetrical star array and the signals were simultaneously digitized at a sample rate of 500 kHz using a lunch-box PC. A portable VCR recorded the images from an underwater camera located adjacent to the array center.