Facts about signature whistles of bottlenose dolphins, Tursiops truncatus

Data collected from wild and captive bottlenose dolphins, Tursiops truncatus , over the past five decades indicate that they produce individually distinctive signature whistles that function in individual recognition and in maintaining group cohesion. However, a recent study by McCowan & Reiss (2001, Animal Behaviour , 62 , 1151–1162) failed to detect signature whistles in nine of 12 captive bottlenose dolphins. These authors suggested that previous studies of signature whistles had used biased data sets, and claimed that the visual classification methods used by most researchers were inferior to their computerized technique. To evaluate their claims, we randomly selected 20 whistles from each of 20 bottlenose dolphins from recordings made during brief capture–release events in Sarasota Bay, FL, U.S.A., and asked 10 judges to visually group spectrograms based on similarity of their contours. Judges consistently grouped whistles according to the identity of the vocalizer; the mean number of whistles of a single dolphin in the judges' groups was 18.9 ± 1.6 out of 20 possible; resampling simulations indicate that it is highly unlikely ( P

[1]  J. Mann,et al.  Use of signature whistles during separations and reunions by wild bottlenose dolphin mothers and infants , 1993, Behavioral Ecology and Sociobiology.

[2]  Randall S. Wells,et al.  Signature whistles of free-ranging bottlenose dolphins Tursiops truncatus: stability and mother-offspring comparisons , 1990, Behavioral Ecology and Sociobiology.

[3]  Randall R. Reeves,et al.  The Bottlenose dolphin , 1990 .

[4]  Diana Reiss,et al.  Whistle contour development in captive-born infant bottlenose dolphins (Tursiops truncatus): Role of learning. , 1995 .

[5]  P. Tyack,et al.  Whistle sharing in paired male bottlenose dolphins, Tursiops truncatus , 2004, Behavioral Ecology and Sociobiology.

[6]  R. Wells,et al.  Signature–whistle production in undisturbed free–ranging bottlenose dolphins (Tursiops truncatus) , 2004, Proceedings of the Royal Society of London. Series B: Biological Sciences.

[7]  D. K. Caldwell,et al.  Individualized Whistle Contours in Bottle-nosed Dolphins (Tursiops truncatus) , 1965, Nature.

[8]  Randall S. Wells,et al.  Sex difference in signature whistle production of free-ranging bottlenose dolphins, Tursiops truncates , 1995, Behavioral Ecology and Sociobiology.

[9]  J. W. Boughman,et al.  Greater spear-nosed bats give group-distinctive calls , 1997, Behavioral Ecology and Sociobiology.

[10]  Alexander Ya. Supin,et al.  Marine Mammal Sensory Systems , 1992, Springer US.

[11]  Randall Wells,et al.  Bottlenose dolphin (Tursiops truncatus) calves appear to model their signature whistles on the signature whistles of community members , 2004, Animal Cognition.

[12]  Peter L. Tyack,et al.  DEVELOPMENT AND SOCIAL FUNCTIONS OF SIGNATURE WHISTLES IN BOTTLENOSE DOLPHINS TURSIOPS TRUNCATUS , 1997 .

[13]  P. Slater,et al.  Context-specific use suggests that bottlenose dolphin signature whistles are cohesion calls , 1998, Animal Behaviour.

[14]  J. Buck,et al.  Captive dolphins, Tursiops truncatus, develop signature whistles that match acoustic features of human-made model sounds. , 2002, The Journal of the Acoustical Society of America.

[15]  D. K. Caldwell,et al.  Vocalization of Naive Captive Dolphins in Small Groups , 1968, Science.

[16]  Randall S. Wells,et al.  2. Dolphin Social Complexity: Lessons from Long-Term Study and Life History , 2003 .

[17]  L. Lefebvre,et al.  Cetaceans Have Complex Brains for Complex Cognition , 2007, PLoS biology.

[18]  D. K. Caldwell,et al.  STATISTICAL EVIDENCE FOR INDIVIDUAL SIGNATURE WHISTLES IN THE SPOTTED DOLPHIN, STENELLA PLAGIODON. , 1970 .

[19]  J. W. Boughman,et al.  Vocal learning by greater spear–nosed bats , 1998, Proceedings of the Royal Society of London. Series B: Biological Sciences.

[20]  Scott,et al.  Estimating bottlenose dolphin population parameters from individual identification and capture-release techniques , 1990 .

[21]  E. D. Brown,et al.  Social influences on vocal development: What birds with complex social relationships can tell us about vocal learning: Vocal sharing in avian groups , 1997 .

[22]  Randall S. Wells,et al.  The Social Structure of Free-Ranging Bottlenose Dolphins , 1987 .

[23]  C. Clark,et al.  Communication and Acoustic Behavior of Dolphins and Whales , 2000 .

[24]  LAURANCE R. DOYLE,et al.  Quantitative tools for comparing animal communication systems: information theory applied to bottlenose dolphin whistle repertoires , 1999, Animal Behaviour.

[25]  Charles T. Snowdon,et al.  Social Influences on Vocal Development , 2005 .

[26]  Diana Reiss,et al.  The fallacy of ‘signature whistles’ in bottlenose dolphins: a comparative perspective of ‘signature information’ in animal vocalizations , 2001, Animal Behaviour.

[27]  Whitlow W. L. Au,et al.  Hearing by Whales and Dolphins , 2000, Springer Handbook of Auditory Research.

[28]  Peter L. Tyack,et al.  Animal social complexity : intelligence, culture, and individualized societies , 2003 .

[29]  V. Janik,et al.  Signature whistle variations in a bottlenosed dolphin, Tursiops truncatus , 1994, Behavioral Ecology and Sociobiology.

[30]  Melba C. Caldwell,et al.  10 – Review of the Signature-Whistle Hypothesis for the Atlantic Bottlenose Dolphin , 1990 .

[31]  Michael D. Scott,et al.  Individual recognition in wild bottlenose dolphins: a field test using playback experiments , 1999, Animal Behaviour.

[32]  P. Slater,et al.  Bird Song: Biological Themes and Variations , 1995 .

[33]  Cynthia F. Moss,et al.  Social Sounds: Vocal Learning and Development of Mammal and Bird Calls , 2003 .

[34]  V. Janik,et al.  Signature whistle shape conveys identity information to bottlenose dolphins. , 2006, Proceedings of the National Academy of Sciences of the United States of America.

[35]  VINCENT M. JANIK,et al.  Pitfalls in the categorization of behaviour: a comparison of dolphin whistle classification methods , 1999, Animal Behaviour.

[36]  Kenneth S. Norris,et al.  Dolphin societies : discoveries and puzzles , 1991 .

[37]  B. McCowan,et al.  Maternal aggressive contact vocalizations in captive bottlenose dolphins (Tursiops truncatus): Wide‐band, low‐frequency signals during mother/aunt‐infant interactions , 1995 .

[38]  D. Fripp.  BUBBLESTREAM WHISTLES ARE NOT REPRESENTATIVE OF A BOTTLENOSE DOLPHIN'S VOCAL REPERTOIRE , 2005 .

[39]  V. Janik,et al.  Whistle matching in wild bottlenose dolphins (Tursiops truncatus) , 2000, Science.

[40]  C. Barnard.  Kin recognition: problems, prospects, and the evolution of discrimination systems , 1990 .

[41]  Randall S. Wells,et al.  Bottlenose Dolphins as Marine Ecosystem Sentinels: Developing a Health Monitoring System , 2004, EcoHealth.

[42]  P. Corkeron,et al.  EVIDENCE FOR SIGNATURE WHISTLE PRODUCTION BY A PACIFIC HUMPBACK DOLPHIN, SOUSA CHINENSIS , 2001 .

[43]  Jeanette A. Thomas,et al.  Sensory abilities of cetaceans : laboratory and field evidence , 1991 .

[44]  P. Tyack,et al.  Whistle repertoires of two bottlenosed dolphins, Tursiops truncatus: mimicry of signature whistles? , 1986, Behavioral Ecology and Sociobiology.

[45]  B. Truax.  Acoustic Communication , 1985 .