Underwater Behavior of Blue Whales Using a Suction-cup Attached CRITTERCAM
Calambokidis, J. 2002. Underwater Behavior of Blue Whales Using a Suction-cup Attached CRITTERCAM. Final Technical Report to Office of Naval Research for Grant Number: N00014-00-1-0942. 7pp
We deployed an instrument package developed by National Geographic (CRITTERCAM) on blue whales at three locations and time periods to examine their underwater behavior. Deployments were conducted in Monterey Bay, southern California Bight, and Sea of Cortez, Mexico. In total, 17 deployments were made, with 8 deployments and recoveries of 15 min to over 6 h. We have developed more effective approaches resulting in an increased success rate in attaching tags, and improved the performance of the Crittercams themselves. Deployments have revealed that: 1) whales were feeding by conducting multiple upward lunges into prey, 2) whales were coming into the krill layer from below and then inverting, 3) lunges brought the whales to near stand-still within dense layers of krill, 4) blue whales were diving deeper (300 m) than had previously been reported, 5) most animals were not vocalizing during feeding, and 6) there did not appear to be close spacing or coordination between pairs of whales.