title: Vocal reporting of echolocation targets: dolphins often report before click trains end.
abstract: Bottlenose dolphins (Tursiops truncatus) wore opaque suction cups over their eyes while stationing behind an acoustically opaque door. This put the dolphins in a known position and orientation. When the door opened, the dolphin clicked to detect targets. Trainers specified that Dolphin S emit a whistle if the target was a 7.5 cm water filled sphere, or a pulse burst if the target was a rock. S remained quiet if there was no target. Dolphin B whistled for the sphere. She remained quiet for rock and for no target. Thus, S had to choose between three different responses, whistle, pulse burst, or remain quiet. B had to choose between two different responses, whistle or remain quiet. S gave correct vocal responses averaging 114 ms after her last echolocation click (range 182 ms before and 219 ms after the last click). Average response for B was 21 ms before her last echolocation click (range 250 ms before and 95 ms after the last click in the train). More often than not, B began her whistle response before her echolocation train ended. The findings suggest separate neural pathways for generation of response vocalizations as opposed to echolocation clicks.
authors.affiliation: National Marine Mammal Foundation, 2240 Shelter Island Drive, San Diego, California 92106, USA. sridgway@ucsd.edu
authors.forename: S H
authors.initials: SH
authors.lastname: Ridgway
authors.forename: W R
authors.initials: WR
authors.lastname: Elsberry
authors.forename: D J
authors.initials: DJ
authors.lastname: Blackwood
authors.forename: T
authors.initials: T
authors.lastname: Kamolnick
authors.forename: M
authors.initials: M
authors.lastname: Todd
authors.forename: D A
authors.initials: DA
authors.lastname: Carder
authors.forename: Monica
authors.initials: M
authors.lastname: Chaplin
authors.forename: T W
authors.initials: TW
authors.lastname: Cranford
mesh_terms: D000818:Animals; D050681:Bottle-Nosed Dolphin / Q000502:physiology*; D004455:Echolocation / Q000502:physiology*; D004867:Equipment Design; D005260:Female; D008568:Memory / Q000502:physiology; D021641:Recognition, Psychology / Q000502:physiology; D012683:Sensory Deprivation / Q000502:physiology; D013018:Sound Spectrography; D013997:Time Factors; D014828:Vocalization, Animal / Q000502:physiology*