Aloha Friends and Colleagues,

Herzing, D. L., Pack, A. A., Delfour, F., Starner, T., Mason, C.,
Gilliland, S., Ramey, C., & Kohlsdorf, D. (2024). Imitation of
computer-generated sounds by wild Atlantic spotted dolphins (*Stenella
frontalis*). *Animal Behavior and Cognition, 11*(2), 136-166.
https://doi.org/10.26451/abc.11.02.02.2024

Since 1985 a community of wild Atlantic spotted dolphin (*Stenella
frontalis*) have been observed underwater in the Bahamas. A human-worn,
acoustic underwater two-way communication interface was developed and
deployed from 2013-2016. Dolphins were exposed to an acoustic referentially
based wearable underwater computer/interface. A model/rival system was used
with dolphins and human participants during in-water sessions. Artificial
and natural objects were labeled with computer generated sounds. Female
juvenile spotted dolphins dominated the activity. Group size averaged seven
dolphins for an average duration of 37 minute over 58 sessions. Of 243
video audio imitations and 56 Cetacean Hearing Augmentation Telemetry
(CHAT) audio imitations, six potential response types were documented and
measured.  *Stand-alone* vocal contour mimics and Frequency *Modulated
Contours* were the most common imitations. Within 5 sec of a
computer-generated sound playing, of the 191 non-stand-alone vocal
responses that were produced, 114 of them (59.7%) were judged as partial
accurate matches, 3 of them (1.57%) were judged as non-matching partial
imitations of a computer-generated sound, 67 of them (35.08%) were
signature whistles, and seven of them (3.67%) were either non-signature
whistle vocalizations or a mimic of the start or end tones. Thus, the
majority of vocalizations produced by the dolphins within five seconds of a
computer-generated sound were partial accurate imitations for the
computer-generated sound played. Dolphins demonstrated both immediate and
delayed vocal imitation and flexible attempts at imitation but did not show
signs of a functional understanding of object labels. Atlantic spotted
dolphins showed vocal flexibility in reaction to humans broadcasting
computer generated sounds.


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