Please read the abstract in the 00front part of this document / Dissertation (MSc (Zoology))--University of Pretoria, 2006. / Zoology and Entomology / unrestricted

The bottlenose dolphin Tursiops truncatus is an extremely well-studied species. We have an extensive knowledge of certain aspects of their vocal behaviour, particularly from captive contexts. Bottlenose dolphins produce a rich tapestry of vocalisations, however, which have historically received minimal attention. Resident groups of bottlenose dolphins frequent the waterways of Fiordland in southwest New Zealand. These deep, sheltered fiords are ideally suited for acoustic studies. This thesis presents the first detailed study of bottlenose dolphin acoustics in New Zealand. Both narrowband and broadband systems were used to record the vocalisations of two resident groups. Effort was distributed evenly over three years for both Doubtful Sound and Milford Sound. From 875 recordings, I proposed a repertoire of 15 discrete calls. These categories were subsequently compared using parameters measured from almost 2000 individual vocalisations. Various multivariate techniques revealed some redundancy in the proposed repertoire, and it was subsequently reduced to 12 calls. The 12 call repertoire was compared between the potentially interbreeding populations of Doubtful Sound and Milford Sound. Fiord-specificity was revealed for many of the calls, particularly the sequenced calls and whistles. These differences suggest bottlenose dolphins use dialects, in keeping with studies of killer whales and sperm whales. As Fiordland dolphins are out of sight for 90% of the time, acoustic techniques allow inference in to subsurface behaviour. I investigated sequential relationships among sounds and between sounds and behaviours. Many calls were strongly implicated in social interactions. The vocalisations ratchet, orca and the sequenced calls were associated with periods of conflict. A number of the click-based calls were linked to diving and presumed foraging events. Inference on the functional significance of sounds allowed an interpretation of habitat use. This appears to be the first study relating the entire vocal repertoire of a cetacean population to a complete home range. Areas important for socialising, foraging and resting are proposed. Local management decisions may be well served by this information. This study uses benign techniques to build on previous research in Fiordland, and adds a new dimension to the study of these populations.

Vocalization patterns of two groups of captive Francois' langurs (Presbytis francoisi) were studied between August 1989 and June 1990. During the 11 months of observation, 109 hours of vocalization recordings were made at Metro Washington Park Zoo, Portland, and the San Diego Zoo, San Diego. Based on the behavioral observations and the vocalization recordings, two categories of vocalization types are described. Type I consists of 20 basic patterns including infant vocalizations and a vocalization recorded by other observers. Type II consists of 3 patterns related to stereotypic behavior and possible stress under captive conditions. Physical characteristics and the context of behavior for each call type are described. Spectrograms are given for all call types except the loud call. Among the calls recorded, whistle vocalizations of infants are the longest in duration. Comparison of vocalization patterns of P. francoisi to those of other species of the genus Presbytis revealed similarities in behavior and context among some call types in the species of P. entellus and P. johnii. / Graduation date: 1992

Alarm or warning vocalizations are produced by many animals when they detect a potential predator. However little is known about the information contained in these vocalizations. This study investigated the warning vocalisations of three passerine species, viz. the Buff-streaked Chat Oenanthe bifasciata, the Stonechat Saxicola torquata and the Bronze Mannikin Spermestes cucullatus. The study investigated whether the alarm calls for terrestrial predators differ in their acoustic structure from alarm calls emitted for aerial predators. Birds were exposed to latex terrestrial snakes and mounted aerial raptors, while changes in six acoustic parameters of alarm calls were measured. Bronze Mannikins were investigated for differences in intra-specific alarm calls between familiar and unfamiliar group members by capturing wild groups of mannikins and randomly mixing these to form assorted groups. Bronze Mannikins emitting warning calls were able to discriminate differences in predator size, and increased their calling rate and decreased the end frequency of the alarm call in response to larger predators. This may be the caller’s response to increased threat or variation in frequency may obscure cues to the caller’s whereabouts. Assorted group members were less aggressive to predator models than original members and panicked more during confrontations. Hence the unfamiliarity of the caller may have disrupted group cohesion. The alarm call acoustics of the social Buff-streaked Chats and the solitary Stonechat were compared to examine the effect of group-living on alarm behaviour. Snakes elicited louder calls from both the chat species than raptors. Louder and collectively more vocal social groups might be more successful in discouraging attacks than an asocial species. Variation in amplitude and call frequencies by the Stonechat provided some evidence that they are equally adapted to identifying predator type. Although Buff-streaked Chats increased their call rate in response to nearby predator models, Stonechats produced shorter calls in response to terrestrial predation particularly when the predators were in close proximity. Knowledge gained through direct encounters with predators or the ease with which raptors and snakes can gain access to nests may have played a part in discrimination of predator threat. Overall this study indicated strong correlations between some alarm acoustic parameters and predator size as well as the degree of threat. / Thesis (M.Sc.)-University of KwaZulu-Natal, 2008.

Through observation of young children much has been learned regarding elementary word acquisition and ordering, sentence formulation, and expansion of verbal experience; but little research regarding what precedes "the word" has been done. The present study was concerned with that period in infancy prior to communicative speech production. The purpose of the present study was to answer the question: Can one selectively reinforce a particular babble?

Žvirblinė pelėda yra plačiai paplitusi, tačiau visame areale saugoma rūšis. ES šalyse šios rūšies apsaugai steigiamos specialios saugomos teritorijos, kuriose pagal Paukščių direktyvą vykdomas rūšies monitoringas. Tačiau iki šiol nėra kiekybiškai analizuotos žvirblinės pelėdos buveinės bei nežinoma, kokiomis sąlygomis ši pelėda dažniausiai vokalizuoja. Todėl šio tyrimo tikslas buvo išanalizuoti žvirblinės pelėdos buveinių pasirinkimą ir vokalizacijos sąlygas. Žvirblinės pelėdos makrobuveinės (200 ha kvadratai, kuriuose 2005-2011 m. buvo fiksuotos žvirblinės pelėdos) darbo metu buvo palygintos su atsitiktinai parinktomis teritorijomis. Nustatyta, kad žvirblinė pelėda teikia pirmenybę didesniam miško plotui makrobuveinėje (82 % ± 18 % SD, n = 178), taip pat eglynams (21 % ± 14 % SD, n = 160) ir brandiems miškams (33 % ± 14 % SD, n = 160), tačiau vengia minkštųjų lapuočių (baltalksnių, tuopų ir gluosnių) medynų (2 % ± 4 % SD, n = 160). Žvirblinės pelėdos buveinių pasirinkimas skyrėsi skirtinguose Lietuvos subregionuose. Nerasta nė vieno kintamojo, kuris būtų svarbus visuose subregionuose. Natūrali žvirblinės pelėdos vokalizacija buvo registruojama 2001-2011 metais, žiemos – pavasario ir rudens – žiemos sezonais. Vokalizacijos datos skirtingais metais skyrėsi, tačiau vidutinė vokalizacijos data žiemos – pavasario sezonu buvo kovo 20 d. (n = 117), rudens – žiemos sezonu – spalio 12 d. (n = 42). Nustatyta, kad pagrindiniai pelėdos vokalizacijai įtaką darantys veiksniai yra... [toliau žr. visą tekstą] / The Eurasian Pygmy Owl (Glaucidium passerinum L.) is a widely distributed and protected species all over its distribution range. There are special protected areas in EU countries, where species’ monitoring is carried out under EU Birds directive. However, there is a lack in quantitative data on species macrohabitat, habitat preferences, and vocalization conditions. This thesis addresses these issues. The Eurasian Pygmy Owl macrohabitats – squares of 200 ha, where territorial owls were located in 2005 - 2011 – were compared with randomly selected 200 ha squares. It was ascertained that the Pygmy Owl prefers forest (82 % ± 18 % SD, n = 178) with spruce (21 % ± 14 % SD, n = 160) and mature stands (33 % ± 14 % SD, n = 160) in its macrohabitats. It avoids deciduous trees like the Grey Alder, poplar and willow (2 % ± 4 % SD, n = 160). On the other hand, the Eurasian Pygmy Owl inhabits various types of forests in distinct sub-regions of Lithuania. There was no single variable, which was more important than others for the species habitat use in three analysed sub-regions, however, different preferred/avoided variables emerged. Natural Eurasian Pygmy Owl vocalization was registered 2001 - 2011, during two seasons per year. The date of vocalization varied between years, however, the average date of owl vocalization was 20th of March in winter - spring season (n = 117) and 12th of October in autumn - winter season (n = 42). It was found, that the key factors affecting the Eurasian Pygmy... [to full text]

Infants are perceptually sensitive to rising pitch over falling pitch (Sullivan & Horowitz, 1983) and this is reflected in their ability to discriminate between questions and declaratives in maternal speech (Soderstrom, Ko, & Nevzorova, 2011). Questions are proposed to play a fundamental role in the acquisition process by soliciting vocalization on the part of the infant (Snow, 1977). In the current study, we explored whether infant vocal responses to questions were distinct from those to declaratives; in particular, whether the use of questions by mothers encouraged greater vocalization by infants. Contrary to our hypothesis, infant vocalizations were no more likely to occur in response to questions. Infants responded more to questions when they were defined by rising pitch contours rather than falling ones. Infants did not respond more to declaratives with rising pitch contours. Questions, in combination with rising pitch contour, may provide especially salient response cues for infants. We propose that infants rely on these perceptual cues to learn when to respond during vocal exchanges with their mothers.

Infants are perceptually sensitive to rising pitch over falling pitch (Sullivan & Horowitz, 1983) and this is reflected in their ability to discriminate between questions and declaratives in maternal speech (Soderstrom, Ko, & Nevzorova, 2011). Questions are proposed to play a fundamental role in the acquisition process by soliciting vocalization on the part of the infant (Snow, 1977). In the current study, we explored whether infant vocal responses to questions were distinct from those to declaratives; in particular, whether the use of questions by mothers encouraged greater vocalization by infants. Contrary to our hypothesis, infant vocalizations were no more likely to occur in response to questions. Infants responded more to questions when they were defined by rising pitch contours rather than falling ones. Infants did not respond more to declaratives with rising pitch contours. Questions, in combination with rising pitch contour, may provide especially salient response cues for infants. We propose that infants rely on these perceptual cues to learn when to respond during vocal exchanges with their mothers.

Long calls are highly stereotyped calls used by primates to communicate across distances; the function of these calls has been debated. Goustard (1983:405) defines them as " ... an extended utterance which has a high degree of structural organization." Habitat structure has been considered a shaping force of the acoustic structure of nonhuman primate long calls as part of the local adaptation hypothesis (Brown et al. 1995). This study examines the effect of phylogeny, habitat density, diet, and social and mating systems as seen through the structure of the fundamental frequency (the lowest frequency of the call; Rogers 2000; Ey, Pfefferle, and Fischer 2007). Results of ANOVA and post hoc tests indicate there are both phylogenetic and habitat-related influences in the acoustic structure of the first phrase (first part of the long call separated from the next by a discrete break). Dietary preferences and social and mating systems are also correlated with acoustic structure.

This PhD. thesis focuses on the vibrational communication of subterranean mammals, in particular, vocal communication of bathyergids (Heliophobius argenteocinereus, Fukomys mechowii, Fukomys darlingi) and seismic communication of Tachyoryctes. We recorded and analyzed the vocalization of three species and discussed the physical parameters of their vocalization in relationship to the special underground acoustic environment. Moreover, social systems of African mole-rats range from solitary to eusocial and thus our results enabled us to discuss the influence of sociality on vocal repertoire richness and its composition. Long distance communication possesses many challenges in underground environments; the only effective mean is seismic communication. We described for the first time seismic signaling in Tachyoryctes and proposed its function.