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The bulbul family Pycnonotidae is an Old-World group of tropical birds that plays important roles in tree seed dispersal. The behavior and vocalization of bulbuls have been studied only in a few species. The objective of the present study is to describe, for the first time, the acoustic and social behavior of three species of bulbuls of the genus Pycnonotus: the sooty-headed bulbul (P. aurigaster), the streak-eared bulbul (P. conradi), and the stripe-throated bulbul (P. finlaysoni). Field studies were conducted from November 2021 to May 2022 in Cat Tien National Park, Dong Nai Province, Vietnam, where all three species are sympatric and tend to inhabit disturbed biotopes. We analyzed "observations," that is, a single record of a bird or a group of birds of a given species. During each observation (about 800 in total), the behavior of the birds was described and, when possible, vocalizations were recorded. The total duration of phonograms of all three species amounted to about 227 min. The sooty-headed and streak-eared bulbuls are social birds that maintained pairs throughout the year, but often, especially during the nonbreeding season, gathered in larger groups. Pair members and individuals from neighboring pairs maintained acoustic contact with each other all the time. To do so, they used calls: broadband calls (noise sounds without clear structure, but with a wide continuous frequency spectrum) emitted by streak-eared bulbuls, and tonal calls (musical sounds showing one clearly defined frequency) by sooty-headed bulbuls. Both these species were only rarely observed singing, this possibly being due to reduced territorial behavior in these birds. The stripe-throated bulbul differs from the other two in singing more frequently, along with producing calls, and song could be used for territorial purposes. We assume that territorial behavior is better expressed in stripe-headed bulbuls than in the other two species. However, even stripe-throated bulbuls did not react to playback-simulated territorial intrusion in our experiments. We assume that vocalizations play important roles in the communication of the three species because we noted these sounds or others in almost all observations. Moreover, we observed a general increase in vocal activity at the beginning of the breeding season (February–March). In addition, during this time, bulbuls were most often those to sing. [ABSTRACT FROM AUTHOR]

The amphibians of the Indonesian island of Sumatra are poorly known, despite it being recognized as a biodiversity hotspot. For determining conservation priorities, up-to-date knowledge of the state of amphibian diversity in Sumatra is crucial, particularly considering the high deforestation rate on the island. To address this, I compiled and analysed a comprehensive dataset for amphibians known from Sumatra, to identify knowledge gaps and assess the significance of these data for conservation on the island and, more broadly, across Indonesia. The compilation indicates there are 135 amphibian species currently recorded for Sumatra, 55% more than the number known in 1923. Approximately 44 species have been described since 2000. Associated data on larvae and calls is lacking for many species. Although 66% of the amphibians of Sumatra are categorized as Least Concern on the IUCN Red List, this may not represent the actual conservation status of these species because many of the assessments are outdated. In addition, 14% of species have not yet been evaluated. This study highlights the need for more comprehensive studies on the amphibians of Sumatra.

The amphibians of the Indonesian island of Sumatra are poorly known, despite it being recognized as a biodiversity hotspot. For determining conservation priorities, up-to-date knowledge of the state of amphibian diversity in Sumatra is crucial, particularly considering the high deforestation rate on the island. To address this, I compiled and analysed a comprehensive dataset for amphibians known from Sumatra, to identify knowledge gaps and assess the significance of these data for conservation on the island and, more broadly, across Indonesia. The compilation indicates there are 135 amphibian species currently recorded for Sumatra, 55% more than the number known in 1923. Approximately 44 species have been described since 2000. Associated data on larvae and calls is lacking for many species. Although 66% of the amphibians of Sumatra are categorized as Least Concern on the IUCN Red List, this may not represent the actual conservation status of these species because many of the assessments are outdated. In addition, 14% of species have not yet been evaluated. This study highlights the need for more comprehensive studies on the amphibians of Sumatra. [ABSTRACT FROM AUTHOR]

The acoustic repertoires of long-finned pilot whales (Globicephala melas) in the Mediterranean Sea are poorly understood. This study aims to create a catalogue of calls, analyse acoustic parameters, and propose a classification tree for future research. An acoustic database was compiled using recordings from the Alboran Sea, Gulf of Lion and Ligurian Sea (Western Mediterranean Basin) between 2008 and 2022, totalling 640 calls. Using a deep neural network, the calls were clustered based on frequency contour similarities, leading to the identification of 40 distinct call types defining the local population’s vocal repertoire. These categories encompass pulsed calls with varied complexities, from simplistic to highly intricate structures comprising multiple elements and segments. This study marks the initial documentation of the vocal catalogue of long-finned pilot whales in the Mediterranean Sea. Subsequent research should delve deeper into this multifaceted communication system and explore its potential linkages with social structures.

Abstract The reaction of birds to the nest parasite, the European cuckoo Cuculus canorus, has been the subject of extensive testing in various aspects. However, while the cuckoo is a long-distance migrant, some of its hosts are sedentary species. In this study, we aimed to investigate whether species, primarily hosts, react to the presence of the cuckoo also in the winter season. This behaviour may involve an attempt to drive the parasite away from locations that will subsequently become their breeding sites. During playback experiments conducted in the winter of 2021/2022 in Poland, we demonstrated that numerous bird species react to the male cuckoo calls in winter. These calls may be perceived as a source of danger, particularly by cuckoo hosts, who responded to this call more frequently than non-hosts and the control species (pigeon). Nonetheless, the birds’ reactions were not strong, as they did not approach the source of the call. However, our results are constrained by the limited number of cuckoo host species wintering in Poland. To better evaluate the intensity of bird responses to the male cuckoo’s call during the non-breeding season, further studies should be conducted in regions where a greater variety of species, especially those most susceptible to parasitism, overwinter.

Acoustic communication, such as bird song, is vital in animal ecology, facilitating reproduction, feeding, defense, and more. Variation in bird song may result from adaptation to environmental features such as anthropogenic noise. The vocal repertoire of raptors is essentially unstudied, particularly in urban environments. The aim of this work was to describe and quantify the acoustic repertoire of Chimango Caracaras (Milvago chimango) in rural and urban areas in La Pampa Province, Argentina. I recorded 26 1-min sound samples at each of four breeding colonies (one rural and three urban) during the austral reproductive season of 2021–2022. I recorded 241 vocalizations corresponding to nine clearly distinct call types. Two types of calls made up 50.6% and 19.5% of the vocalizations and seven others made up <10.0% each. Three call types had trills (fast repetitive notes). Average percentage of call types differed significantly between the two habitats (P < 0.01), with more trills produced in rural habitats. Average calling rate was 6.6 ± 5.1 calls/min at rural colonies and 10.7 ± 10.7 at urban colonies. The number of different call types produced was 2.1 ± 1.6 types/min at rural colonies and 2.7 ± 1.8 at urban colonies. The greater calling rate of Chimango Caracaras in urban areas may represent an attempt to improve signal effectiveness among the anthropogenic acoustic clutter. La comunicación acústica, como el canto de las aves, es vital en la ecología animal, al facilitar la reproducción, alimentación, defensa y otras actividades. La variación en el canto de las aves puede deberse a la adaptación a características ambientales como el ruido antropogénico. El repertorio vocal de las rapaces ha sido poco estudiado, especialmente en entornos urbanos. El objetivo de este trabajo fue describir y cuantificar el repertorio acústico de Milvago chimango en áreas rurales y urbanas en la provincia de La Pampa, Argentina. Registré 26 muestras de sonido de 1 minuto de duración cada una provenientes de cuatro colonias reproductivas (una rural y tres urbanas) durante la temporada reproductora austral de 2021–2022. Registré 241 vocalizaciones correspondientes a nueve tipos de llamadas claramente distintas. Dos tipos de llamadas representaron el 50.6% y el 19.5% de las vocalizaciones y otras siete representaron <10.0% cada una. Tres tipos de llamadas tuvieron trinos (notas rápidas y repetitivas). Los porcentajes de tipos de llamadas difirieron significativamente entre los dos hábitats (P<0.01), con más trinos producidos en hábitats rurales. La tasa de llamadas fue de 6.6 ± 5.1 llamadas/minuto en colonias rurales y 10.7 ± 10.7 en colonias urbanas. El número de tipos de llamadas diferentes producidas fue de 2.1 ± 1.6 tipos/minuto en colonias rurales y 2.7 ± 1.8 en colonias urbanas. La mayor tasa de llamadas de M. chimango en áreas urbanas puede representar un intento de mejorar la efectividad de la señal ante la distorsión acústica antropogénica. [Traducción del equipo editorial] [ABSTRACT FROM AUTHOR]

Background: National suicide prevention strategies are general population-based approaches to prevent suicide by promoting help-seeking behaviors and implementing interventions. Crisis helplines are one of the suicide prevention resources available for public use, where individuals experiencing a crisis can talk to a trained volunteer. Samaritans UK operates on a national scale, with a number of branches located within each of the United Kingdom's 4 countries or regions. Objectives: The aim of this study was to identify any differences in call duration across the helpline service in order to determine whether service varied interregionally and intraregionally and to determine the impact of calls answered in the same region as the caller, compared with calls answered in a different region on the duration of calls made from landlines to Samaritans UK. Methods: Calls may be routed by Samaritans, wherein the telephony system sends the call to the next available volunteer, irrespective of location; therefore, individuals may be routed to a branch within the same region as the caller's current region (intraregional calls) or routed to a branch that is in a different region from that of the caller's current region (interregional calls). The origin of calls by region was identified using the landline prefix of the anonymized caller identifier, along with the region of the destination branch (as branch details are recorded in the call details record). First, a Levene's test of homogeneity of variance was carried out for each condition, that is, England calls and Scotland calls. Thereafter, for each condition, a one-way ANOVA or one-way analysis of means was carried out to evaluate any significant differences in call duration. Results: ANOVA results showed that there are significant differences in call durations between intraregional calls and interregional calls (P<.001). Across all conditions within this study, callers stayed on the phone for a shorter period of time when routed to a branch that is within the same region as the call origin than if they were put through to a branch within a different region than the call origin. Conclusions: Statistical analyses showed that there were significant differences between interregional and intraregional calls. On average, callers to crisis helplines stayed on the phone for a shorter period of time if they were routed to a branch within the same region in which the call originated than if they were routed to a branch in a different region of origin. The findings from this study have practical applications, which may allow crisis helplines to manage their resources more effectively and improve caller satisfaction with the service. [ABSTRACT FROM AUTHOR]

The acoustic repertoires of long-finned pilot whales ( Globicephala melas ) in the Mediterranean Sea are poorly understood. This study aims to create a catalogue of calls, analyse acoustic parameters, and propose a classification tree for future research. An acoustic database was compiled using recordings from the Alboran Sea, Gulf of Lion and Ligurian Sea (Western Mediterranean Basin) between 2008 and 2022, totalling 640 calls. Using a deep neural network, the calls were clustered based on frequency contour similarities, leading to the identification of 40 distinct call types defining the local population's vocal repertoire. These categories encompass pulsed calls with varied complexities, from simplistic to highly intricate structures comprising multiple elements and segments. This study marks the initial documentation of the vocal catalogue of long-finned pilot whales in the Mediterranean Sea. Subsequent research should delve deeper into this multifaceted communication system and explore its potential linkages with social structures., Competing Interests: We declare we have no competing interests., (© 2024 The Authors.)