These actions appeared almost aggressive in nature. The sustained high-speed swimming during the latter part of our encounter is noteworthy considering the presence of a neonate only about an hour old. Based on our experience with this population, we conclude that the behavior of this group during the entire encounter was unusual. Similar behaviors may provide cues for future observers for detecting parturition events. The event is particularly meaningful because of the long history of research on this population of killer whales.
Information is available on the age and maternal relatedness of the identified whales.
Many of these whales were in direct physical contact with the neonate within minutes of birth. We would like to thank Alex Rhodes, Seacoast Expeditions, Victoria, for use of one of the observation boats, and Larry Dill, Simon Fraser University, for use of the other. We thank Glen Hvenegaard and two anonymous reviewers for editorial suggestions. Observations on the birth and development of a captive-born killer whale Orcinus orca . Balcomb, K.C. 1974.