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Understanding drivers and monitoring changes of biodiversity forms the basis for evidence-based management and policy recommendations that aim to reduce biodiversity loss and to ensure the delivery of ecosystem services on which we rely. Ecoacoustic monitoring can be applied across large spatial and temporal scales, offering the potential for less resource-intensive ecosystem monitoring. Indices of acoustic diversity have been shown to correlate with species richness of various taxa, as well as vegetation and landscape structure. In order to apply ecoacoustic monitoring at large scales we need to improve our understanding of the effects of local and regional land-use on acoustic patterns, and assess how temporal aspects of acoustic patterns can be integrated in these analyses. We hypothesized that land-use intensity and landscape structure affect species richness and composition of birds and orthopteran, and therefore indirectly affect acoustic diversity and composition. To test this, we set up autonomous recording systems in grassland plots along land-use intensity gradients in three regions in Germany. We applied structural equation modelling to analyze the direct and indirect drivers of acoustic diversity and composition, including mowing and grazing intensities, landscape diversity, distance to the nearest road, vascular plant species richness as well as bird and orthopteran species richness and composition. Single indices of acoustic diversity did not reflect changes in bird or orthopteran species richness, making them poor predictors for local land-use related changes in species richness in grassland plots. Acoustic composition (non-metric multidimensional scaling combination of mean monthly acoustic indices at different day phases), however, did relate to differences in landscape structure, land-use intensity, vocalizing species composition and orthopteran species richness. We propose the developed acoustic composition metric as suitable proxy to detect ecosystem changes in grasslands. • Acoustic composition relates to species composition of birds and orthopterans. • Local land-use intensities and landscape structure affect soundscapes. • Acoustic composition is a suitable proxy to detect ecosystem changes in grasslands. [ABSTRACT FROM AUTHOR]

The sounds present inside a beehive originate from the overlap of honeybee buzzes with external sounds. They reveal patterns that support the hypothesis that the sonic context of the beehive may be utilized by honeybees as a source of ecoacoustic codes for communication and the coordination of social activity. Patterns were observed in a data series of acoustic files sampled at a frequency of 48 kHz during the period May-July 2023 in a beehive of Apis mellifera ligustica (Spinola, 1806). The acoustic information was extracted using the acoustic complexity index (ACIt f ) algorithm applied to a fast Fourier transform matrix. Data series, aggregated in 1368 min × 512 frequency bins × 61 days, were tentatively classified according to three temporal classes of aggregation (eight, six, and four clusters, respectively) using the hierarchical K-means clustering algorithm. The clusters obtained at these three resolutions were considered potential ecoacoustic codes (PECs) belonging to each minute of the data series. The number of discontinuities along the 24-h PEC sequence, the coefficient of variation of the number of PECs at daily and seasonal scales, and the PEC sample entropy confirmed a patterned distribution of PECs across the 24 h, modulated at a monthly scale. A significant correlation was found between these indices and the daily average wind speed, and temperature. Honeybee buzz is an informative medium used by honeybees to develop survival strategies., Competing Interests: Declaration of competing interest We declare that we have not interest and that we have not received funds for this paper. Sincerely., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Ecological codes have been defined as every biological code integrated by factors originated by the environmental context that participates in the codepoiesis process. Ecological codes create a strict relationship between the inner world of organsims and the external relational world, and represent the mechanism with which the vivo-scape is realized. Acoustic codes are used in nature to decode acoustic signals between individuals of the same or different species and belong to the category of biological codes. Ecoacoustic codes are the outcome of the evolution of acoustic codes, and results as the interplay between acoustic codes and environmental factors. Soundtope codes represent the results of emerging properties of the acoustic communities., Competing Interests: Declaration of competing interest We declare that we have not interest, and that we have not received funds for this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

In a development of the ecosemiotic vivo-scape concept, a 'safety eco-field' is proposed as a model of a species response to the safety of its environment. The safety eco-field is based on the ecosemiotic approach which considers environmental safety as a resource sought and chosen by individuals to counter predatory pressure. To test the relative safety of different locations within a landscape, 66 bird feeders (BF) were deployed in a regular 15 × 15 m grid in a rural area, surrounded by shrubs, small trees, hedgerows, and buildings. On each of 48 days in November 2021 and February and March 2022, dried mealworms were placed on each BF and counts of larvae at each BF were made at noon and dusk. The European robin ( Erithacus rubecula ) and the great tit ( Parus major ) were the most regular visitors to the BFs. Land cover at each BF was recorded. Bird behaviour at the BFs was noted from direct video recordings of the birds at nine selected BFs, totalling 32 daily sessions in March. The different behaviours of the European robin and the great tit were observable. The safety eco-field changed according to the month and the time of day. The distance of the BF from the woodland edges seemed to be important only in the morning. In the afternoon, BFs that were more distant from the woodland edges received the highest number of visits. Weather conditions were found to influence the number of mealworms removed, but this requires further investigation. A significant relationship between land cover and the number of mealworm larvae removed from the BFs was observed. Within the grid of BF, three regions were distinguishable which were related to land cover in the safety eco-field process. The experimental framework confirms the adequacy, at least for birds that have cryptic predators, to map the landscape as a proxy of safety resource. From the video recordings it was noted that the European robin visits were distributed throughout the day without apparent temporal preferences, while the great tit visits were concentrated in the central part of the day. This result has the limitation of the short period of observation (March) and should be extended to the entire period of the experiment to eventually capture seasonal variation. The experimental evidence obtained confirms that the ecosemiotic-based models of safety eco-field are an efficient approach to explain bird feeding preferences and behaviours., Supplementary Information: The online version contains supplementary material available at 10.1007/s12304-023-09522-1., Competing Interests: Competing InterestsThe authors declare no competing interests.Conflict of Interest Authors have no conflict of interest to declare., (© The Author(s), under exclusive licence to Springer Nature B.V. 2023, Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

Multi-layer communication and sensing network assures the exchange of relevant information between animals and their umwelten, imparting complexity to the ecological systems. Individual soniferous species, the acoustic community, and soundscape are the three main operational levels that comprise this multi-layer network. Acoustic adaptation and acoustic niche are two more important mechanisms that regulate the acoustic performances at the first level while the acoustic community model explains the complexity of the interspecific acoustic network at the second level. Acoustic habitat and ecoacoustic events are two of the most relevant mechanisms that operate at the third level. The exchange of ecoacoustic information on each of these levels is assured by ecoacoustic codes. At the level of individual sonifeorus species, a dyadic intraspecific exchange of information is established between an emitter and a receiver. Ecoacoustic codes discriminate, identify, and label specific signals that pertain to the theme, variation, motif repetition, and intensity of signals. At the acoustic community level, a voluntarily or involuntarily communication is established between networks of interspecific emitters and receivers. Ecoacoustic codes at this level transmit information (e.g., recognition of predators, location of food sources, availability and location of refuges) between one species and the acoustically interacting community and impart cohesion to interspecific assemblages. At the soundscape level, acoustic information is transferred from a mosaic of geophonies, biophonies, and technophonies to different species that discriminate meaningful ecoacoustic events and their temporal dynamics during habitat selection processes. Ecoacoustic codes at this level operate on a limited set of signals from the environmental acoustic dynamic that are heterogeneous in time and space, and these codes are interpreted differently according to the species during habitat selection and the completion of phenological cycles. The process of ecoacoustic coding can be interpreted according to the eco-field theory, which describes the procedures utilized by a receiver to intercept and optimize acoustic information. The acoustic codes may be detected and identified using mathematical models that simulate their performances. The Acoustic Complexity Indices are an appropriate tool to investigate the acoustic codes in action on all three levels. Ecoacoustic codes are powerful agencies used by sound-adapted species to cope with environmental novelties, and their efficiency may represent an important divide between whether a species perpetuates or becomes extinct., (Copyright © 2017 Elsevier B.V. All rights reserved.)

An acoustic community is defined as an aggregation of species that produces sound by using internal or extra-body sound-producing tools. Such communities occur in aquatic (freshwater and marine) and terrestrial environments. An acoustic community is the biophonic component of a soundtope and is characterized by its acoustic signature, which results from the distribution of sonic information associated with signal amplitude and frequency. Distinct acoustic communities can be described according to habitat, the frequency range of the acoustic signals, and the time of day or the season. Near and far fields can be identified empirically, thus the acoustic community can be used as a proxy for biodiversity richness. The importance of ecoacoustic research is rapidly growing due to the increasing awareness of the intrusion of anthropogenic sounds (technophonies) into natural and human-modified ecosystems and the urgent need to adopt more efficient predictive tools to compensate for the effects of climate change. The concept of an acoustic community provides an operational scale for a non-intrusive biodiversity survey and analysis that can be carried out using new passive audio recording technology, coupled with methods of vast data processing and storage., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)