bioacoustics article: Nature 428, 29 April 2004

[Dave Mellinger <>]

Andrew D. Foote, Richard W. Osborne, and A. Rus Hoelzel
 Nature Vol. 428, p. 910
 29 April 2004
 
 Background noise can interfere with the detection and discrimination
 of crucial signals among members of a species. Here we investigate the
 vocal behaviour in the presence and absence of whale-watcher boat
 traffic of three social groups (pods) of killer whales (Orcinus orca)
 living in the nearshore waters of Washington state. We find longer
 call durations in the presence of boats for all three pods, but only
 in recent recordings made following a period of increasing boat
 traffic. This result indicates that these whales adjust their
 behaviour to compensate for anthropogenic noise once it reaches a
 threshold level.