Vocalization of Western Tarsier (Cephalopachus bancanus Horsfield, 1821) in Bangka Island, Indonesia

Every tarsier species performs different vocalization behaviour. Cephalopachus bancanus as one of the tarsier species listed as vulnerable in the IUCN red list has limited and different information about their vocalization. This research was designed to explore the species vocalization in the vicinity of Petaling Village, District of Bangka, Bangka Island, Indonesia. Tarsier vocalization inside temporary enclosures was recorded using a handy recorder and analysed using bioacoustics software Audacity 2.3.3 and Raven Pro 1.6.1. We described seven vocalization types with different functions and spectrogram patterns. One type of vocalization, squeak, is produced only by the infant. Two types of vocalizations (whistle and cheeps) were produced by the infant and adult, and four vocalization types were performed by adults. Those types of vocalizations can be heard within human hearing. Some types of vocalizations have peak frequencies at the ultrasonic level, i.e.: agonistic scream, alarm call, distress call, and hysteresis.

Bioacoustic Characteristics of the Crimean Gecko Mediodactylus danilewskii (Strauch, 1887) (Reptilia: Sauria: Gekkonidae)

For the first time, the amplitude-frequency and temporal characteristics of the acoustic signals (the distress one and two types of advertisement calls) of the Crimean gecko (Mediodactylus danilewskii) were analyzed. The distress call is a rather long one (usually around 150–350 ms, but sometimes up to nearly 1 s), with a peak frequency of 6.86 kHz in both males and females. The upper harmonics of this type of signal lie in the ultrasonic region of the frequency spectrum. The short advertisement call has a different duration in males and females, namely, about 23 ms and 35–40 ms on average, respectively. The peak frequency of this type of signal is 4.82 kHz in both sexes. Some frequency parameters of the acoustic signals are characterized by lower values in males than those in females, despite the larger body sizes of the latter. E.g., 35% and 11% of the total distress call energy is below 4 kHz in males and females, respectively. The average value of the fundamental frequency of short advertisement calls in males and females is 1.75 kHz and 3.33 kHz, respectively, while the limits of variability of this parameter in representatives of both sexes almost do not overlap. The prospects of using bioacoustics for solving important issues of the Mediodactylus (kotschyi) superspecies taxonomy are discussed. We assume that the male long advertisement call, which is a sequence with a duration of 4 to 9 s consisting of 24–44 clicks with an average peak frequency below 4 kHz following each other at a rate of 6.4–9.1 clicks/s, will be most informative for these goals.

Call Types of the Oriental Magpie Robin (Copsychus saularis) in Suburban Areas in Kota Samarahan, Sarawak

The Oriental Magpie Robin (Copsychus saularis) is among the popular passerines songbird in Borneo. A study on the vocalisation of this tropical species has been conducted at Universiti Malaysia Sarawak (UNIMAS) Campus and Tanjung Bundong village areas, Kota Samarahan, Sarawak starting from March 2015 until February 2017 to understand more on their call types. Call samples were recorded from 38 individuals of Magpie Robin (8 colour-ringed males, 6 colour-ringed females, 10 juveniles and 14 nestlings) during breeding seasons. A total of six call types were successfully identified which were territorial, threat, submissive, juvenile, distress and begging calls. Both territorial and threat calls are uttered in response to the presence of an intruder in the vicinity of nesting sites while begging call is crucial to the nestlings as it stimulates parental food provisioning activities. Distress call was uttered when in stress situations while juvenile calls were associated with learning process to vocalise. Territorial, threat and begging calls were substantially important during breeding season and the survival of Magpie Robins.

Spectral entropy of early-life distress calls as an iceberg indicator of chicken welfare

Chicks ( Gallus gallus domesticus ) make a repetitive, high energy ‘distress’ call when stressed. Distress calls are a catch-all response to a range of environmental stressors, and elicit food calling and brooding from hens. Pharmacological and behavioural laboratory studies link expression of this call with negative affective state. As such, there is an a priori expectation that distress calls on farms indicate not only physical, but emotional welfare. Using whole-house recordings on 12 commercial broiler flocks ( n = 25 090–26 510/flock), we show that early life (day 1–4 of placement) distress call rate can be simply and linearly estimated using a single acoustic parameter: spectral entropy. After filtering to remove low-frequency machinery noise, spectral entropy per minute of recording had a correlation of −0.88 with a manual distress call count. In videos collected on days 1–3, age-specific behavioural correlates of distress calling were identified: calling was prevalent (spectral entropy low) when foraging/drinking were high on day 1, but when chicks exhibited thermoregulatory behaviours or were behaviourally asynchronous thereafter. Crucially, spectral entropy was predictive of important commercial and welfare-relevant measures: low median daily spectral entropy predicted low weight gain and high mortality, not only into the next day, but towards the end of production. Further research is required to identify what triggers, and thus could alleviate, distress calling in broiler chicks. However, within the field of precision livestock farming, this work shows the potential for simple descriptors of the overall acoustic environment to be a novel, tractable and real-time ‘iceberg indicator’ of current and future welfare.

The weeping vocalization of the screaming hairy armadillo (Chaetophractus vellerosus), a distress call

Distress calls are signals given by individuals experiencing physical stress such as handling by a predator. These calls have been recorded in numerous phylogenetically distant vertebrate species, and share certain acoustic features, such as high amplitude, broadband, and rich harmonic structure. Screaming hairy armadillos (Chaetophractus vellerosus) sometimes give a high-amplitude weeping call when captured by predators or disturbed by humans. We provide an acoustic characterization of this call using recordings of hand-held wild individuals, and test whether it constitutes a distress signal. The weeping call was a harsh, loud, broadband, long sound, composed of five note types: crying, inhaled, inhaled sobbing, exhaled sobbing, and grunt notes. Crying notes were the most common, distinctive, and loudest sounds. The proportion of armadillos that called when disturbed was between nearly five to seven times higher than when treated with care. Likewise, 223 hunters reported armadillos consistently weeping when trapped by dogs, and no weeping was heard in natural undisturbed conditions. Our data support a distress signal role for the weeping call.

Rencontres exceptionnelles

In “Rencontres exceptionnelles” Jean Vanmai offers a thoughtful personal account of his participation in the colloquium “Rencontres”. Taking the perspective of a Caledo-Viet author, whose writing has long been confined to his small home island in the Pacific, he reflects on how his enchanting encounter with a larger community of readers, researchers and, in particular, French and Australian fellow writers of Vietnamese origin reconnected him with his roots and voices of the Vietnamese diaspora. Using the trope of the unanswered letter from a Vietnamese boatperson stranded in a Malaysian refugee camp in the early 1980s, he addresses the painful questions of war, loss and exile. By taking upon himself to respond some forty years later to his compatriot’s distress call, he dwells on the Vietnamese collective past and investigates his own sense of identity and belongingness. He concludes his narrative with the vision of a borderless Vietnamese diaspora where generations of proud descendants of Dragons and Immortals bond and share the same love for the ancestral land. “Rencontres exceptionnelles” est un compte-rendu personnel et réflectif dans lequel Jean Vanmai réfléchit à sa participation au colloque “Rencontres”. En prenant la perspective d’un auteur Calédo-Viet dont l’écriture a été longtemps confinée à sa petite île au cœur du Pacifique, l’auteur se penche sur les rencontres établies avec les lecteurs, les chercheurs et surtout ses confrères franco- et australo-vietnamiens qui l’ont reconnecté à ses racines et à la diaspora vietnamienne. Il utilise le motif de la lettre morte qu’une migrante vietnamienne échouée dans un camp de réfugiés en Malaisie lui a envoyée et qu’il a oubliée pendant une quarantaine d’années pour aborder les questions douloureuses de la guerre, la perte et l’exil. À travers sa réponse tardive à l’appel de détresse de sa compatriote, Vanmai replonge dans le passé collectif vietnamien et examine ses propres sentiments d’identité et d’appartenance. Pour conclure, il offre la vision d’une diaspora vietnamienne sans frontière où les fiers descendants de Dragons et d’Immortels se retrouvent unis dans un même amour de la terre ancestrale.