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The songs of the following species are presented: Conocephalus (Xiphidion) cinereus Thunberg, 1815, C. (X.) ictus (Scudder, 1875), C. (X.) magdalenae Nascrecki, 2000, C. (Anisoptera) strictus (Scudder, 1875), Dichopetala brevihastata Morse, 1902, D. castanea Rehn & Hebard, 1914, D. pollicifera Rehn & Hebard, 1914, Phyllophyllia guttulata Stål, 1863, Stilpnochlora azteca (Saussure, 1859), Boopedon gracile Rehn, 1904, Syrbula montezuma (Saussure, 1861) and Teniopoda tamaulipensis Rehn, 1904. Considerations on distribution, taxonomy, ethology, biodiversity and conservation are given.

Potential predators elicit alarm calls in many birds and mammals. The context-specific occurrence of acoustically distinct alarm call types may allow conclusions about their functions and/or the underlying call system. Furthermore, many group-living species exhibit a co-operative system of vigilance in terms of predator avoidance. In a descriptive field study I investigated alarm calling and sentinel activity in group-living Arabian Babblers Turdoides squamiceps focussing on the context-specificity of call type occurrence in relation to the caller’s behaviour. The results revealed that two of the three different alarm call types were correlated to the distance to the predator: Barks were uttered more frequently to distant and tzwicks to close predators. Sentinels were more likely to utter barks and trills, but foraging group members tzwicks. Results suggest that sentinels detect potential dangers in greater distances and start calling earlier, whereas foraging birds detect predators only closer and therefore utter higher urgency calls. Finally, the results added to the current knowledge of the urgency-based call system of Arabian babblers, in which information can be provided on different levels: Variation in the call structure of single call types, combined use of different call types and discrete use of different call types in different contexts.

In domestic sheep Ovis aries, the mother and the young display a preferential bond for each other that relies on multimodal inter-individual recognition. Lambs show a preference for their own dam shortly after birth, and this is important for their survival. The role of acoustic cues in this early preference for the mother is not clear. The aim of the present work was to analyze the timing of acoustic recognition of the mother and to identify the physical parameters used in the recognition of maternal bleats by the lamb.
In a first study, we investigated the ability of lambs to discriminate between the bleats of their own mother and an alien equivalent mother in a two-choice test. Both ewes were hidden behind a canvas sheet and lambs were not allowed to approach the dams closer than 1 m, thus preventing visual as well as olfactory perception. Tests were conducted 12 hr, 24 hr or 48 hr after birth (n=19 or 20/group). An indication of vocal discrimination was already present at 24 hr and at 48 hr lambs spent significantly more time near their mother than near the alien dam. In a second step, we investigated which physical parameters of the bleats were important for recognition. For this, we conducted playback experiments with modified bleats at two weeks postpartum. Ours results show that lambs pay attention to a combination of various time, energy and frequency parameters: timbre (distribution of energy within the spectrum), amplitude and frequency modulations appear to be the most important parameters encoding the individual signature.
We conclude that vocal recognition between the ewe and her lamb plays an important role in the display of preferential mother-young bond from very early on. Our studies also demonstrate that the encoding of the individual signature is not limited to the frequency domain but rather involves a multiparametric encoding process.

The vocal repertoire of Amazona amazonica during its breeding season has been recorded from wild individuals in Santa Bárbara, Pará State, Brazil. At individual nests, we continuously recorded vocalizations and behaviour for four hours in the early morning and three hours in the late afternoon, three times a week throughout the breeding season. We identified nine vocalizations that we classified in three behavioural categories: (1) Flight call – emitted when parrots arrive in the nest area; (2) Perched contact calls – two different vocalizations, one of them related to feeding, were emitted when the pair was perched in the nest area and interacted socially between themselves or with other individuals; (3) Aggressive calls – emitted when birds were in a dangerous situation, i.e. alarm (three types of calls), agonistic contact and distress calls (two types of call). The Orange-winged Parrot is a highly social species and the complexity of its social interactions is reflected in the diversity of its vocal repertoire.

Whales living within seismically active regions are subject to intense disturbances
from strong sounds produced by earthquakes that can kill or injure individuals.
Nishimura & Clark (1993) relate the possible effects of underwater earthquake noise
levels in marine mammals, adducing that T-phase source signal level (10- to 30- Hz
range) can exceed 200 dB re: 1 µPa at 1 m, for a magnitude 4-5 earthquake, sounds
audible to fin whales which produce low frequency sounds of 16-20/25-44 Hz over
0.5-1s, typically of 183 dB re: 1 µPa at 1 m. Here we present the response of a fin
whale to a 5.5 Richter scale earthquake that took place on 22 February 2005, in
the Gulf of California. The whale covered 13 km in 26 min (mean speed = 30.2 km/
h). We deduce that the sound heard by this whale might have triggered the costly
energy expenditure of high speed swimming as a seismic-escape response. These
observations support the hypothesis of Richardson et al. (1995) that cetaceans may
flee from loud sounds before they are injured, when exposed to noise in excess of 140
dB re: 1 µPa 1 m.

This paper presents a framework effort to allow the experimentation of various devices in order to automatically record, detect and classify marine mammal vocalizations in the open sea. Some tools for the protection of Killer Whales and other cetaceans are founded in the analysis of their recorded vocalizations. With this framework we are able to test every part under controlled conditions before open sea experiments. Some of these devices have been designed to localize and track open sea populations in order to facilitate data collection for conservation management.
At this moment the framework consists of the basic necessary instruments and IT resources for continuously multichannel recording of vocalizations from four specimens of Killer Whale. The enormous raw data stream forces the implementation of a data reduction strategy. As a result, the present research is focused in the development of techniques for this purpose that will allow the automatic classification of events and obtain statistical data. Complementarily, our research goals are also focused on the design of prototypes for source localization using time tags of events on multiple channels for continuous real time logging of behaviour and position of specimens. This paper presents some preliminary results of automatically detected calls.

We present a series of practical techniques designed to standardize, quantify and allow comparison of population information obtained from periodic automated terrestrial recordings of acoustic animals. From the experience obtained mainly from anuran monitoring systems, we discuss issues such as establishing comparable recording levels, calibrating the detection space for each station, establishing correlations with population densities and comparison with other acoustical surveys. We emphasize the need to obtain species-specific data on source levels (sound pressure levels).