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The genus Trypocopris Motschulsky, 1858 includes six species of medium-large size tunnellers, inhabiting pastures and forests of the Palearctic Region. The genus encompasses a large geographical area, but species' ranges are highly fragmented and several subspecies have been recognised and described on morphological grounds. At this very preliminary stage of the research we analysed distress signals of three species (T. alpinus, T. pyrenaeus and T. vernalis) to compare bioacoustic and morphological patterns of variability and differentiation. Insects were collected during the summer of 2000 in north-western Italy and sounds were recorded in an anechoic chamber. Recordings were analysed using Avisoft-SASlab Pro 3.92b software. Four temporal and seven frequency variables were sampled from the displayed waveforms and sonograms. Both inter-sex and inter-specific relationships were examined. A nested analysis of variance showed significant differences between sexes in one temporal and five frequency variables and among species in three temporal and seven frequency variables. A discriminant function analysis significantly discriminated between sexes and among species, suggesting that stridulation distress signals can be considered both sex and species-specific morphological characters.

Mice emit ultrasounds (70 ± 5 kHz) in infancy as well as in adulthood. Both male and female NMRI mice emit ultrasounds during the first 3 minutes of presentation of a conspecific female. The number of calls recorded is higher in female-female than in male-female pairs. If the same female is represented after a short interval of time to the conspecific the amount of calls uttered decreases. This suggests that ultrasounds can be used as an index of social memory. The time interval necessary to determine this decrease, following successive exposure to the same female, is different in male and female mice. In contrast to males, females show lower ultrasonic emission when the same female is reintroduced in their home cage four hours after the first exposure. In contrast, these animals emit a similar amount of calls when a different female is presented after the same time interval. If 24 hrs elapsed from the first presentation, the ultrasonic performance of males and females does not change according to the familiarity with the female partner. This suggests that females are able to recognise a female conspecific after a four-hour time interval, whereas males' ultrasonic performance is not affected by the characteristics of the female partner. A detailed behavioural analysis of the first minutes of male-female and female-female interaction was conducted to ascertain if different motivational systems are involved according to the sex of the vocalising animals.

Research into the rutting behaviour and territoriality of male alpine chamois Rupicapra rupicapra rupicapra (L. 1758) was done in Gran Paradiso National Park during November - December 1995. The area of study covers the left mountain of the high Orcos Valley, between 1,950 and 2,300 metres elevation. Data acquisition in the field was made from 5 November to 3 December 1995 (the chamois rutting season): a total of 88 hours of observation. The observation distance ranged from 20 to 300 metres. Animals observed were nine adult males from seven to eleven years old, and one of six, marked with radiocollars and / or eartags. 31 kinds of behaviours, which are the base of male-male and male-female social interactions (aggressive or not) have been described. In this ambit I will consider the Rut Call, which is a vocal display of dominance and threat, used by the male chamois in the two contexts of aggression and courtship. It is a sonorous grunt of a relatively low pitch, emitted through the nose and, most of all, the mouth, with the tongue extended. Of the total Rut calls recorded, I considered just those from four males having the meaning of beginning an aggressive interaction between males (Lovari & Locati 1991). These calls are at a time (first lo-day period), when those interactions appear longer and more ritualised then the second lo-day period when, while as the rut season advances, they become more violent and energetically costly. Since the call is produced also by isolated males and since Marking behaviour shows the same progression as the Rut call during the rutting season, 1 interpreted the Rut call as a vocal marking behaviour, connected to the defence of the hypothetical "territories'' (Giametta 1996, degree thesis). In the case of the Rut calls addressed to females, it assumes a meaning of vocal threat towards females which attempt to leave the herd. It is emitted repeatedly, furthermore, by males before and after mounting. Finally it is shown that the older males, who have the greatest reproductive success, emit to females a greater number of Rut calls than the younger males.

The transmission of high frequency sound through the environment has been studied using continuous and pulsed sound. The bush cricket Leptophyes punctatissima is able to communicate very successfully at ultrasonic frequencies, hence it is a significant biological model to use. Measurements of attenuation were made using a signal broadcast over reflecting and absorbing surfaces and over a pre-calibrated series of glasspapers, artificial surfaces for which there are also S.E.M. images available. Measurements of sound radiation around a singing insect suggest that leaf angle influences the reflection of sound at 40 kHz. It may be possible to identify potential acoustical effects that have enabled Leptophyes punctatissima to communicate so effectively at this high frequency, though it may also be the case that the insect's own size and shape have also determined the use of this particular frequency.

Nature sounds are treasure boxes of information. They give us some clues as to the sound sources in terms of the identity, life cycle and interactions with other elements in the environment. They also tell us the type and nature of different events that take place close to or afar in the environment. The range and significance of nature sounds is the general foundation for the study of sound environments. Different habitats respectively hold the unique sound environment in terms of their acoustical characteristics and sound source species composition (SSSC). The acoustical indices such as taxonomic groups, locality bonds and trophic levels have made it possible to carry out environmental surveys without imposing a harmful effect on the local ecosystem as the conventional methods of collection and capture tend to do. SSSC monitored in a local area will be the main source for diagnosing and assessing the environment. In order to make use of such treasure boxes of nature sounds, however, we first need to learn properly how to listen to and hear nature sounds using our own ears. As part of the sound and environmental education, I would like to propose .a sound map method. The sound map is a handy way for both children and adults to describe and discover the sound environment. It is also an effective way to develop their hearing sensitivity and aural recognition of nature sounds in an enjoyable manner. Further, the sound map provides us with the means to share the image of sound environment with other people and is a good foundation for communicating and making decisions on it. To show the potentials of sound map method in monitoring and diagnosing environments, a pilot study made at a planned site of EXPO 2005 in Kaisho-no-mori Forest, Aichi, Japan is briefly introduced.

Collections of animal sound recordings serve many uses in education, entertainment, science and nature conservation. The first animal sound recording dates from as early as 1889, although systematic collecting did not begin until the 1950s. The largest collections between them now hold around 0.5 million recordings with their associated data. They preserve the sounds of all kinds or animals with multiple examples of their seasonal, geographical and individual variations. For example, the British Library National Sound Archive (NSA) has 140,000 recordings of more than 10,000 species of birds, mammals, insects and amphibians, donated by numerous individual scientists and amateur recordists worldwide. Preserving such large collections for the long term is a primary concern in the digital age. While digitisation and digital preservation have many advantages over analogue methods, the rate of technology change and lack of standardisation is a serious problem for the world's major audio archives. Techniques to reduce the risk of obsolescence include technology preservation, migration or emulation. Another challenge is to make collections more easily and widely accessible via electronic networks. On-line catalogues are already available for some collections (NSA collection: www.cadensa.bl.uk ; Borror collection: blb.biosci.ohio-state.edu/). Providing internet access to the actual audio is the next goal although because currently the data rate of most internet connections is slow compared to CD quality audio rates of 706 kbps, on-line recordings are short, low-quality clips of the archival versions.

The organisation of scientific knowledge and the tools of information retrieval have traditionally been discipline-based, an approach which is effective for a homogenous user-base. However, profound changes in the presentation of scientific thought, notably an increase in collaboration and a blurring of the literary boundaries between disciplines, call for corresponding changes in the electronic information retrieval systems designed to serve the complex information needs of interdisciplinary scientists. This paper describes a project to address this challenge, by studying the information-seeking behaviour of the members of a representative interdisciplinary science organisation, the International Bioacoustics Council (IBAC), and identifying the problems they encounter in using discipline-based information systems. The presentation will include a summary of findings from the survey and demonstration of a prototype system design to facilitate interdisciplinary information seeking (supported by Institute of Museum and Library Service-LL90187 National Organization for Hearing Research and NIMH-58198).

Male frogs produce acoustic signals that are used by females for recognition of conspecific mates. For communication to be efficient, mate recognition requires that there is a functional association between the signal (sender) and the response properties of the sensory system that decodes the signal (receiver). This correlation between signal and receiver can, by promoting assortative mating, restrict genetic exchange among populations and is therefore thought to constitute a crucial component in speciation. We recorded advertisement calls of Philautus spp. (Ranidae, Rhacophorinae) from the Western Ghats, India. In order to get as much information as possible out of the collected data, optimal analysing tools have to be developed. Frequency is generally considered to be one of the important species recognition cues. To analyse the frequency content (spectrum) and to observe changes in the sound spectrum (spectrogram), the traditional approach used in bioacoustics is based on Fourier analysis. A recent alternative to this classical tool is wavelet analysis, which has become quite popular in several disciplines both in theory and in practice. So far, however, it has been little used in bioacoustics. By computing wavelet transforms of the samples of the digitally recorded frog croaking, a more subtle analysis can be achieved and some chirps, which can hardly be detected through a Fourier analysis, are clearly revealed by wavelet techniques. Such wavelet-based analysis is expected to be of great help in identifying a set of most significant sound characteristic features or "signatures'' on which a more efficient population discrimination can be based. An understanding of the basis of such discrimination is expected to lead to a better insight into the evolution of the frog acoustic communication system.

The latest version of the real-time Digital Signal Processing Workstation developed at CIBRA runs in a standard Windows environment and can use a wide range of sound acquisition devices. It can operate on a notebook computer to allow in-field use. Depending on the acquisition devices, recording, analysis and display can be performed in real-time up to 500 ksamples/sec to provide useful bandwidth to more than 200 kHz. At present, National Instruments DAQ devices, which are available in PCI, FireWire and PCMCIA standards, can be used. On a PIII 500MHz notebook it is possible to acquire, analyse, display and record at 320 ksamples/sec (single channel) with a PCMCIA card and at about 500 ksamples/sec with a FireWire device. The software was primarily developed for bioacoustical studies, though it can be used in a wide range of tasks requiring continuous broadband monitoring.

There is growing concern that aquatic vertebrates may be affected by the increasing noise of anthropogenic origin in their environment. Several studies have been conducted on the effects of noise on marine mammals, but only a few studies have dealt with fish. The aim of the present study is to measure and compare the immediate effects of intense noise exposure (160 dB re 1 µPa for 12 and 24 hours) on two otophysine fish species, the non-vocal cyprinid Carassius auratus and the catfish Pimelodus pictus, which produces low-frequency drumming and high-pitched stridulatory-sounds. The second aim of this study was to determine the effects of noise on the ability of P. pictus to communicate acoustically. Hearing sensitivity was determined utilising the auditory evoked potential (AEP) recording technique. Measurements were performed prior and directly after noise exposure as well as after several days of recovery. Threshold shifts immediately after noise exposure ranged from 13-22 dB in C. auratus and from 7-34 dB in P. pictus. In both species the greatest hearing loss occurred at their most sensitive frequencies (C. auratus: 500 - 1000 Hz; P. pictus: 500-4000 Hz). Sound energies in the pimeloid catfish were maximally 10 dB above hearing curves immediately after noise exposure. Differences in recovery were observed between species. Carassius auratus recovered completely after 3 days, whereas in Pimelodus pictus reduced auditory sensitivity of up to 15 dB was still observed after 3 days. Our results showed that these two hearing specialists are differently affected by noise exposure and that the threshold shifts are more persistent in P. pictus. The hearing loss in the vocalising pimelodid catfish indicates that sound communication is impaired in noisy environments. This research was supported by the Austrian Science Fund (FWF No 12411 to F.L.).