Microgeographic Variation and Sharing of the Gargle Vocalization and Its Component Syllables in Black-Capped Chickadee (Aves, Paridae, Poecile atricapillus) Populations

Throughout the year during agonistic encounters, black-capped chickadees (Poecile atricapillus) emit a vocal signal known as the gargle call. Each bird has a repertoire of structurally differing gargle calls; some are shared with others in the local area. As a basis for understanding the cultural evolution of this social signal, we initiated a study of gargle call repertoires of birds living in a narrow belt of continuous riparian habitat occupied throughout by a resident population of chickadees. During two consecutive winter seasons, we sampled repertoires at three locations over a distance of 8.4 km to quantify micro-geographical variation. Analyses of vocal sharing and population differentiation were carried out on whole gargle calls and on the individual acoustic units (syllables) from which the whole calls are constructed. We analysed 28 380 calls of 46 subjects in the two seasons of study. Birds averaged 7.6 different calls in their gargle repertoires. Calls were composed of about 10 syllables on average. Fifty-six different syllables were used to construct the calls of all birds. Each study site had some gargle calls unique to the local birds and some that were shared with one or both of the other two sites. There was significantly greater sharing of both calls and syllables among birds within sample sites than between sample sites. The frequencies of the different kinds of gargles and syllables were significantly correlated across the 2 yr of the study, but the correlation was stronger (r 2 = 0.93) for syllables than for whole gargle calls (r 2 = 0.61).

[1]  M. C. Baker,et al.  A COMPARISON OF GARGLE CALLS OF BLACK-CAPPED CHICKADEES RECORDED IN THE LABORATORY AND IN THE FIELD , 2000 .

[2]  M. C. Baker,et al.  Black-capped chickadee call dialects along a continuous habitat corridor , 1999, Animal Behaviour.

[3]  S. Peters,et al.  Song-type sharing in song sparrows: implications for repertoire function and song learning , 1998, Behavioral Ecology and Sociobiology.

[4]  M. C. Baker,et al.  Gargle vocalizations of black-capped chickadees: test of repertoire and video stimuli , 1996, Animal Behaviour.

[5]  M. Ficken,et al.  Long-term persistence of a culturally transmitted vocalization of the black-capped chickadee , 1995, Animal Behaviour.

[6]  M. C. Baker,et al.  Effects of gargle vocalizations on behavior of black-capped chickadees , 1991 .

[7]  M. Ficken,et al.  A complex vocalization of the black-capped chickadee. II: Repertoires, dominance and dialects , 1987 .

[8]  C. Weise,et al.  A complex call of the black-capped chickadee (Parus atricapillus). I. Microgeographic variation , 1984 .

[9]  J. Craig,et al.  The evolution of complexity in broadcast song of passerines , 1982 .

[10]  M Andersson,et al.  Why are there so many threat displays? , 1980, Journal of theoretical biology.

[11]  M. C. Baker,et al.  Discrimination of Gargle Calls by Black-Capped Chickadees (Poecile atricapillus) , 1999 .

[12]  J. P. Hailman,et al.  The organization of major vocalizations in the paridae , 1989 .

[13]  Robert W. Ficken,et al.  VOCAL REPERTOIRE OF THE BLACK-CAPPED CHICKADEE , 1978 .

[14]  K A Shiovitz,et al.  The process of species-specific song recognition by the indigo bunting, Passerina cyanea, and its relationship to the organization of avian acoustical behavior. , 1975, Behaviour.