摘要:

Nuttall's white-crowned sparrowZonotrichia leucophrys nuttalliand the Puget Sound white-crowned sparrowZ. i. pugetensisintergrade through a zone of hybridization in northern California. The songs of the two differ in the sequence of syllable types and in the phonology of the complex syllables. We did a playback experiment to males of both subspecies in the field and to females of both subspecies in the laboratory to determine their response to the two subspecies songs. By making alterations of features of the songs, we also attempted to identify characteristics that account for subspecific recognition. Males of both subspecies were more responsive to their own subspecies song than to that of the other subspecies. Substitution of Puget Sound complex syllables into the Nuttall's song caused a reduction in response by male Nuttall's, but alteration of a Nuttall's song to a Puget Sound sequence of syllables had no effect. Females of both subspecies gave more sexual displays when played a song of their own subspecies than when played that of the other subspecies. Female Nuttall's gave an intermediate response when played Nuttall's songs with Puget Sound complex syllables or when played Nuttall's songs altered to a Puget Sound sequence. Puget Sound females did not discriminate between their own subspecies song and either of the altered stimulus songs separately. They did respond less to a song that combined both alterations than to their own subspecies song.

ISSN:0952-4622    

DOI:10.1080/09524622.1994.9753243

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

When studying the acoustic signals of animals, it is often necessary to obtain the precise time structure of the frequency. It is also useful to extract the envelope of a signal or to modify a signal to obtain its frequency modulated part. This can be achieved digitally using the analytic signal concept.

ISSN:0952-4622    

DOI:10.1080/09524622.1994.9753244

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

Bat detectors are commonly used to monitor bat behaviour. Earlier research has suggested that there may be systematic differences in the response of different detectors to bat calls. Such differences would have important implications for the comparability of quantitative surveys conducted with bat detectors. The present study examines variability within and between brands of bat detector in accuracy of tuning, directionality and sensitivity to different types of bat echolocation call in bat detectors from three manufacturers. The consistency of results from a field survey incorporating the three brands in a standardised methodology are also examined. Significant differences were found within and between brands in directionality and sensitivity which would lead to bias in bat surveys. The implications of these findings for bat surveys are discussed, as are the design features of importance for species identification.

ISSN:0952-4622    

DOI:10.1080/09524622.1994.9753245

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

ISSN:0952-4622    

DOI:10.1080/09524622.1994.9753246

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

ISSN:0952-4622    

DOI:10.1080/09524622.1994.9753247

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

ISSN:0952-4622    

DOI:10.1080/09524622.1994.9753248

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

ISSN:0952-4622    

DOI:10.1080/09524622.1994.9753249

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

ISSN:0952-4622    

DOI:10.1080/09524622.1994.9753250

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

ISSN:0952-4622    

DOI:10.1080/09524622.1994.9753251

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

ISSN:0952-4622    

DOI:10.1080/09524622.1994.9753252

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor