A Spectrographic Analysis of the Vocal Repertoire of the African Village Weaverbird

Abstract

The object of this report is to make a contribution toward the understanding and objective portrayal of the vocabulary of a passerine bird. In 19.53, the author, together with a specialist on human linguistics (Collias and Joos, 1953), published a report on the spectrographic analysis of the vocalizations of chickens. There seems to have been no previous spectrographic study of the vocal repertoire of a bird. Since that time the acoustic spectrograph has become quite widely used as an instrumental aid to the study of animal sounds and communication. However, most authors dealing with birds have largely restricted their attentions to the detailed analysis of song patterns. Quite recently, Poulsen (19.58)) working in Denmark, has presented a spectrographic study of the calls of the Chaffinch (Fringilla coelebs), using Marler’s (1956) names of the calls as based on an intensive field study in England. The paper by Marler emphasizes song analysis, but it does not include spectrograms of some of the calls. Gompertz (1961) in Britain has described the vocabulary of the Great Tit (Parus major) using spectrographic analysis. There are many other excellent studies of bird vocalizations, but those studies either lack spectrograms or else illustrate only a few of the calls of a species spectrographitally. This article is not intended to be a comprehensive review of such papers but rather is a report of an attempt to cover the entire vocal repertoire of a species of bird with the aid of spectrographic analysis. A general classification of animal sounds from the viewpoint of communication and of function in the natural life of the animal is available (Collias, 1960). The present report is based on a nine-months’ field study of the eastern Congo race, graueri, of the common Village Weaverbird (Textor cucullatus) in Africa (Collias and Collias, 1959) and especially on observations of a breeding colony of the West African race, cucullatus, held in aviaries on the campus of the University of California at Los Angeles over a period of several years. In general, there was not much difference between the calls of these two races. The spectrograms accompanying this report are all based on tape-recordings made in California. A brief abstract of some of the results has been published (Collias, 1961). This investigation has been supported by Grant G-9741 from the National Science Foundation and Grant 1623 from the University of California at Los Angeles. My wife, Elsie, helped in many ways, particularly by raising a young weaverbird used in the study. I am indebted to my colleague Thomas R. Howell for a critical reading of the manuscript and to W. R. Fish for advice on recording techniques.