摘要:

Male common loons,Gavia immer, produce a territorial vocalization called the yodel. We quantitatively examined yodels using discriminant and cross correlation analysis. Both techniques correctly assigned the majority of the male's yodels to the proper group, however discriminant analysis was more accurate for making long term comparisons of a yodel's stability. Of four male loons in a color marked, breeding population at the Seney National Wildlife Refuge in Michigan, each male's yodel was different and these differences were maintained over the six years of this study. There is a suggestion that changes in the yodel may be related to territory and mate switching, indicating that individuality in the yodel may be linked to female choice.

ISSN:0952-4622    

DOI:10.1080/09524622.1999.9753424

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

The role of male sounds in attracting females and in mating was investigated in the three most common species ofMicronectafound in ponds 60 km NE of Melbourne, Australia:M. concordia, M. tasmanicaandM. robusta.In playback experiments using recorded male signals, females were attracted to signals of conspecific males, in preference to signals of heterospecific sympatric males. Studies of mating behaviour, using video recording, showed that signals were obligatory for mating. These findings strongly suggest that acoustic signalling is important in reproductive isolation inMicronecta.Comparisons between matings and rejected matings showed that, within each species, copulation only occurred following a certain minimum number of acoustic signals with more pulse-trains than the mean for the species. Low amplitude sounds (after signals) were also important in courtship, immediately preceding mating. No sounds occurred during copulation.

ISSN:0952-4622    

DOI:10.1080/09524622.1999.9753425

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

The conspicuous vocalisations of a three-month old cat with craniocerebellar trauma were studied. A temporal coincidence between the improvement of the clinical condition and the change of the vocal utterances was observed. This vocal change could be observed in relevant acoustic parameters but it was seen more clearly in nonlinear phenomena (biphonation, subharmonics and deterministic chaos) in the cat's acoustic repertoire. The vocal change was also recognizable to the unaided ears.

ISSN:0952-4622    

DOI:10.1080/09524622.1999.9753426

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Exact locations of spawning areas used by marine fishes are needed to design marine reserves and estimate spawning stocks. The location of spawning areas of soniferous fishes such as weakfishCynoscion regaliscan be determined by means of passive hydroacoustic surveys. We conducted nocturnal hydrophone surveys at 12 locations in Pamlico Sound in May of 1996 and 1997. Digital audio tapes were made of weakfish “purring” sounds, the tapes were analyzed spectrographically and compared with ichthyoplankton surveys taken at the same stations and times. All weakfish “purring” sounds were recorded at stations near inlets. Maximum sound pressure levels recorded after sunset were 127 dB (re 1 (μPa) for individual weakfish, but reached a maximum of 147 dB when weakfish and other fish were producing sounds simultaneously. The maximum distance that an individual weakfish “purr” can be detected above the background sound, assuming a cylindrical spreading model, is approximately 50 m. There was a strong association (r = 0.78) between the log10— transformed abundance of early-stage sciaenid-type eggs and maximum sound pressure levels, with the greatest numbers occurring at the inlet stations. These results suggest that passive hydroacoustic surveys can be used to delimit spawning areas for conservation and management purposes.

ISSN:0952-4622    

DOI:10.1080/09524622.1999.9753427

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

The study describes the vocal repertoire of the Grey Crowned CraneBalearica regulorum gibbericepsand speculates on the purpose the calls serve. The repertoire consists of 4 tonal and 7 non-harmonic calls. Chicks have 3 different vocalizations.

ISSN:0952-4622    

DOI:10.1080/09524622.1999.9753428

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

The systematic classification of tree frogs(Hyla)inhabiting different regions of the country of Turkey is unclear. Recordings of natural advertisement calls of individual male tree frogs in different locations in Turkey were analyzed to determine variation in acoustic features that may be related to taxonomic status. Multivariate analysis of covariance showed that call duration, intercali interval and number of pulses per call varied significantly between frogs in different locales. Call duration, intercall interval, and number of pulses per call were related to air temperature. Dominant frequency differed significantly between different groups of frogs, and was temperature-independent. These data are consistent with the hypothesis that tree frogs in Turkey represent two distinct species,Hyla arboreaandHyla savignyi.

ISSN:0952-4622    

DOI:10.1080/09524622.1999.9753429

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

This paper presents the acoustic features and the behavioural context of the unison call of the East African Crowned CraneBalearica regulorum gibbericeps.It speculates on the different functions of the unison call according to the situations where it is given. This is tested with the appeasement-threat hypothesis, which claims that the threatening acoustic characteristics of the unison call should be enhanced if it is given as a territorial call. In comparison, the appeasing acoustic characteristics should be stronger if the unison call is performed at flock sites where it possibly serves for mate assessment.

ISSN:0952-4622    

DOI:10.1080/09524622.1999.9753430

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Subterranean rodents are interesting organisms for communication studies because of their fossorial way of life. Acoustic communication in the South American genusCtenomyshas not yet been studied even though this species is geographically widespread. This paper represents a preliminary survey ofCtenomysvocalizations. Three types of vocal signals were identified: S-, C- and G-signals. Using field, laboratory and literature data, we provide interpretations on the possible functions of these signals. S-signals are harsh and low-pitched putative spatial localization signals that may also encode for sexual identification. C-signals are relatively high-pitched and narrow-banded FM vocalizations that are sexual signals used by females in a copulatory context. Finally, G-signals are harsh and patternless sounds that are aggressive signals used in direct encounters with con- or hetero- specific individuals.

ISSN:0952-4622    

DOI:10.1080/09524622.1999.9753431

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

ISSN:0952-4622    

DOI:10.1080/09524622.1999.9753432

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

ISSN:0952-4622    

DOI:10.1080/09524622.1999.9753433

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor