234
D.L. Herzing
monkey society (Seyfarth and Cheney 1980) and warrants caution in
dolphin research. Factors beyond the structure of the call itself include
gender, age class, social context, developmental status, and, possibly, reproductive status. Difficulties in documenting contextual information,
combined with the lack of ultrasonic recordings of conspecific social
vocalizations (as a potential location for supplemental or modulated information), may be responsible, methodologically, for our lack of information
on the details of the hearing of conspecific vocalizations.
3. Atlantic Spotted Dolphin Vocal and
Nonvocal Repertoire
The basic life history, age class categories, and behavioral habits for S.
frontalis have recently been described (Herzing 1996, 1997). A sympatric
species, T truncatus, also shares the same habitat (Herzing and Johnson
1997; Rossbach and Herzing 1997). Previous studies on the behavior and
vocalizations of S. frontalis in captivity also exist (Wood 1953; Caldwell and
Caldwell 1966,1971; Caldwell et al. 1973). Due to the lack of observations
of most delphinid species under natural social conditions, there remains a
significant gap of understanding in the most basic functional and developmental aspects of the hearing and use of conspecific vocalizations.
Following is a detailed account of vocalizations and associated underwater behavior of S. frontalis in various age classes, relationships, and during
interspecific interactions with bottlenose dolphins. Like many social species,
S. frontalis employ vocalizations and postural behavior in a wide range of
behavior contexts. Although many vocalizations under analysis are within
human audible range, there has been little work done on the presence of
ultrasonic information during the use of social sounds. Most data are taken
from Herzing (1996), and a summary of these vocalizatons and contextual
information can be found in Table 5.3. Analysis of the full repertoire and
contextual use of vocalizations of this species should eventually yield a
functional description of these communication signals and how they relate
to the hearing abilities of delphinids in the wild.
3.1 Vocalizations Associated with Contact, Reunions,
and Broadcasting
Frequency-modulated whistles are the predominant vocalizations heard
during behavioral contexts including (1) mother/calf reunions-mothers
produce their own signature whistle after calves depart and until they rejoin
her; (2) alloparental care-older conspecifics, including male and female
dolphins, produce their own signature whistles prior to the retrieval of
younger dolphins; (3) courtship behavior-females and males repetitively
D.L. Herzing
monkey society (Seyfarth and Cheney 1980) and warrants caution in
dolphin research. Factors beyond the structure of the call itself include
gender, age class, social context, developmental status, and, possibly, reproductive status. Difficulties in documenting contextual information,
combined with the lack of ultrasonic recordings of conspecific social
vocalizations (as a potential location for supplemental or modulated information), may be responsible, methodologically, for our lack of information
on the details of the hearing of conspecific vocalizations.
3. Atlantic Spotted Dolphin Vocal and
Nonvocal Repertoire
The basic life history, age class categories, and behavioral habits for S.
frontalis have recently been described (Herzing 1996, 1997). A sympatric
species, T truncatus, also shares the same habitat (Herzing and Johnson
1997; Rossbach and Herzing 1997). Previous studies on the behavior and
vocalizations of S. frontalis in captivity also exist (Wood 1953; Caldwell and
Caldwell 1966,1971; Caldwell et al. 1973). Due to the lack of observations
of most delphinid species under natural social conditions, there remains a
significant gap of understanding in the most basic functional and developmental aspects of the hearing and use of conspecific vocalizations.
Following is a detailed account of vocalizations and associated underwater behavior of S. frontalis in various age classes, relationships, and during
interspecific interactions with bottlenose dolphins. Like many social species,
S. frontalis employ vocalizations and postural behavior in a wide range of
behavior contexts. Although many vocalizations under analysis are within
human audible range, there has been little work done on the presence of
ultrasonic information during the use of social sounds. Most data are taken
from Herzing (1996), and a summary of these vocalizatons and contextual
information can be found in Table 5.3. Analysis of the full repertoire and
contextual use of vocalizations of this species should eventually yield a
functional description of these communication signals and how they relate
to the hearing abilities of delphinids in the wild.
3.1 Vocalizations Associated with Contact, Reunions,
and Broadcasting
Frequency-modulated whistles are the predominant vocalizations heard
during behavioral contexts including (1) mother/calf reunions-mothers
produce their own signature whistle after calves depart and until they rejoin
her; (2) alloparental care-older conspecifics, including male and female
dolphins, produce their own signature whistles prior to the retrieval of
younger dolphins; (3) courtship behavior-females and males repetitively