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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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The Ecoacoustic Event Detection and Identification (EEDI) system is a recent methodology to investigate structure and dynamic of soundscapes. In this study, EEDI has been re-engineered by adding to the Acoustic Complexity Index (ACI) calculated for each temporal step ( ACIf t ) and to its evenness ( ACIf t evenness ), the evenness of ACI calculated along each frequency bin ( ACIt f evenness ), and upgrading the ecoacoustic code (EC) from a two-digit to a three-digit code, thus increasing the analytical resolution of EEDI. Furthermore, a new metric, the Acoustic Information (AI) index, is introduced which is obtained by multiplying the value of each EC by the number of Recording Minutes (RM) in which every EC occurs. The EEDI was tested in four localities within a Mediterranean landscape using Soundscape Explorer [Terrestrial] digital recorders. Based on 273,360 RMs, 436 ECs were detected from a field recording system active from December 2015 to November 2016. The number of ECs and AI values increased in late winter and early spring, followed by a reduction in late spring and summer. A second increase was observed in early autumn. Based on bird phenology, non-significant differences in the number of ECs were found between the breeding (395 ECs) and non-breeding season (417 ECs). The sequence of the ECs during night time resulted in significant differences from the sequence of the ECs during daytime, but the number of RMs and of AI values of ECs exclusive of day or night time resulted negligible. Hourly abundance of ECs and the associated AI showed a similar sequence for all the localities, confirming a common daily pattern in soundscape organization. According to the way in which ECs are distributed along the 24 h, the first hundred more frequent ECs were aggregated into seven major patterns: some ECs have a dominant distribution around sunrise, whereas others prevail at midday or at night. EEDI provides a visual representation of each recording day (240 RMs) in an Euclidean space delimited by ACIf t (x), ACIf t evenness (y) and ACIt f evenness (z). An “asymptotical like” distribution that occurs during rain or wind events, and a “shower jet like” distribution that occurs when biophonies are dominant, are the two major patterns that were discovered. The ecoacoustic codes EC000, EC999, EC997, EC476, and EC271, have been utilized after their identification, to classify and analyze ecoacoustic events as an example of the capacity of EEDI. This holistic approach starting with detection of patterns delimited by the combination of ACI metrics associated with the AI, overcomes the usual procedure to first identify the sources and then determine the resulting patterns. The use of EEDI provides the potential to explore and to compare the characteristics of soundscapes with other environmental variables and represents an innovative and flexible ecological indicator. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Climate change is an important cause of the irreversible transformation of habitats, of the rapid extinction of species, and of the dramatic changes in entire communities, especially for tropical assemblages and for habitat- and range-restricted species, such as mountaintop and polar species. In particular, climate change effects several aspects of animal sounds (e.g., song amplitude and frequency, song post, and sound phenology). Animal sounds, which are life traits characterized by high plasticity, are able to cope with even modest variations of environmental fundamentals like vegetation cover, land mosaic structure, temperature, humidity, and pH (for aquatic medium). Moreover, the climatic effects on these biophonies can be observed earlier than change in vegetation patterns and visible landscape structures. Ecoacoustics, the discipline that investigates the role of sound on animal ecology from species to landscapes, offers robust models, such as acoustic adaptation, acoustic niche, acoustic active space, acoustic community, and acoustic phenology to investigate the effect of climate change on species, populations, communities, and landscapes. From an operational perspective, ecoacoustics procedures can be applied in different contexts, such as locations, weather, species, populations, behavior, physiology, and phenology. In addition, thematic priorities can be selected, such as latitudinal and altitudinal gradients, restricted habitats, stopover areas, extreme environments, weather conditions, short distance migrants, species at high vocal plasticity, sink-source status, active space, social attraction, physiological modifications, dawn and dusk choruses, sound from stressed plants, and time series analysis. The noninvasiveness of passive acoustic recording, the simultaneous collection of important data, such as community richness and diversity, immigration and extinction events, and singing dynamics as well as the availability of innovative noninvasive technologies operating over a long-term period, establish ecoacoustics as a new and important tool with which it is possible to analyze massive acoustic data sets and quickly predict and/or evaluate the effects of climate change on the environment. Moreover, passive recording is supported by cheap, user-friendly field sensors and robust data processing and may be part of the citizen science research agenda on climate change. [ABSTRACT FROM AUTHOR]

Ecoacoustic techniques using multiple acoustic sensors and two metrics of the acoustic community -- the acoustic complexity index (ACI) and the chorus ratio (CR) -- were successfully used to describe and characterize the morning acoustic activity of birds according to three equal temporal intervals during spring 2013: Dawn Chorus, Post Chorus 1, and Post Chorus 2.The metrics were applied across five Italian Mediterranean locations (Valenza, Madonna dei Colli, Monte Curto, Virolo, Croce di Tergagliana) that differed by land-cover typologies. Results from the ACI metrics showed a peak during the Dawn Chorus and a visible lull close to sunrise between Dawn Chorus and Post Chorus 1 .The lull was evident in all localities except Valenza, where singing activity was relatively constant across the successive morning intervals. Temperature and vegetation structure were confirmed as important factors associated with morning acoustic activities. Vegetation evenness and temperature across the season was negatively correlated with ACI, whereas CR was positively correlated with temperature and vegetation diversity. Of the 33 species of birds identified during the maximum dawn chorus activity. Blackcap, Blackbird, European Robin, and Great Tit were acoustically dominant and their activity was significantly higher before sunrise except for Blackcap, whose acoustic activity showed no significant differences across time intervals. The dawn chorus is one of the most conspicuous behaviours of birds, engendering much speculation but no definitive, univocal explanations. The ecoacoustic approach opens a new perspective for investigating this complex phenomenon. [ABSTRACT FROM AUTHOR]

The Red-billed Leiothrix (Leiothrix lutea) is an invasive species which has recently been found to be locally abundant in eastern Liguria (Italy). The song production of this bird was recorded over the course of an entire year (2011) and evaluated using both aural information and applying innovative automatic processing metrics. Our findings revealed that the Red-billed Leiothrix has loud vocalizations that are heard for most of the year, including in July and August when other birds are silent. Its song production has been estimated to amount to 37% of the sounds uttered by the entire bird community. The next most vocal species are the European Robin (36%), the Common Blackbird (18%), the Subalpine Warbler (5%) and the Sardinian Warbler (1%). The Red-billed Leiothrix can be seen as a new acoustically dominant species and, consequently, a potential modifier of the soundscape patterns of the indigenous bird community. The modification of acoustic traits in the repertoire of both indigenous species and the Red-billed Leiothrix is to be expected according to a co-evolution hypothesis. [ABSTRACT FROM AUTHOR]

An altered acoustic environment can have severe consequences for natural communities, especially for species that use acoustic signals to communicate and achieve breeding success. Numerous studies have focused on traffic noise disturbance, but the possible causes of road effects are inter-correlated and the literature on noise qua noise is sometimes contradictory. To provide further empirical data in this regard, the authors investigated the spatio-temporal variability of the singing dynamics of an avian community living in an acoustic context altered by traffic noise. Fieldwork was carried out in a wood of Turkey oaks (central Italy) bordered on one side by a main road. The soundscape was examined by positioning eight digital recorders, distributed in two transects perpendicular to the road, and recording between 6:30 and 8.30 a.m. for 12 continuous sessions. The acoustic complexity index was used to obtain a quantification of singing dynamics, which were positively correlated with traffic noise. This may indicate that birds try to propagate their signals with greater emphasis (e.g., amplified redundancy or loudness of the songs) to override the masking effect of noise. Nevertheless, an ecotonal effect could have influenced the correlation results, with this enhanced dynamic possibly being due to a more densely populated environment. [ABSTRACT FROM AUTHOR]

In territorial songbirds, duets between mates represent one of the best-known examples of communal display, with the main function being the defence of joint resources. In this study, we found evidence of a coordinated choral display performed by neighbouring heterospecific songbirds. In such choruses, most of the participating species perform a deliberate temporal overlap of songs, thus suggesting agonistic behaviour. However, they then utilize a complex form of behaviour to avoid signal jamming, making the aggressive purpose unlikely. We define these displays as "coordinated interspecific choruses". We recorded dusk choruses of songbirds living in a mixed turkey oak wood in central Italy, and then carried out a niche overlap analysis using null models that were intended for investigations of concurrent emissions of songs, finding that species tend to sing concurrently instead of using the refractory period of another species. Among the species singing concurrently, about half used the same frequency range, but instead of finding considerable spectral overlap between their vocalizations, the number of real spectral overlaps was lower than would be expected by chance. We propose a tentative explanation for this, where such choruses are the expression of the existence of a neighbourhood of different species that has evolved a communal signal that is similar to that used by mates in a pair, i.e. coordinated vocalizations. As coordination requires experience of each other's songs, we propose that evolution has selected individuals that are more skilled at learning heterospecific songs. [ABSTRACT FROM AUTHOR]

The Mediterranean region shows unique environmental and ecological characteristics. The observed ecological complexity is the result of a long-lasting and intense co-evolutionary process between human and non-human organisms. Most of the valuable landscapes at the present time are under serious threat from agricultural intensification, land abandonment and forestation, urban sprawl, and mass tourism. The urgency of conservation clashes against these threats. Such complexity of human–nature interactions is best represented by the “full and empty” world ecological model. Cultural landscape and niche construction theories belong to this framework. In turn, perception and cognition are central themes in the definition of such paradigms. This leads ecological research into the field of eco-semiotics, a new scientific perspective that can provide powerful tools for the study of the Mediterranean ecological complexity, as it addresses the interpretation of signs that human and other evolutionary drivers leave in the environment. Such signs are the expression of mutual interactions that shaped patterns and processes in the region. The eco-field paradigm, derived from the eco-semiotic approach, is a theoretical tool that allows one to intercept a portion of such signals to model the relationship between any species and its environment. [ABSTRACT FROM AUTHOR]

Abstract: Landscape ecology deals with ecological processes in their spatial context. It shares with ecosystem ecology the primate of emergent ecological disciplines. The aim of this contribution is to approach the definition of landscapes using cognitive paradigms. Neutral-based landscape (NbL), individual-based landscape (IbL) and observed-based landscape (ObL) are defined to explore the cognitive mechanisms. NbL represents the undecoded component of the cognitive matrix. The IbL is the portion of landscape perceived by the biological sensors. ObL is the part of the cognitive matrix perceived using the cultural background of the observer. The perceived landscape (PL) is composed by the sum of these three approaches of landscape perception. Two further types of information (sensu Stonier) are recognized in this process of perception: the compressed information, as it is present inside the cognitive matrix, and the decompressed information that will structure the PL when a semiotic relationship operates between the organisms and the cognitive matrix. Scaling properties of these three PL components are recognized in space and time. In NbL scale seems irrelevant, in IbL the perception is filtered by organismic scaling and in ObL the spatio-temporal scale seems of major importance. Definitively, perception is scale-dependent. A combination of the cognitive approach with information paradigms to study landscapes opens new perspectives in the interpretation of ecological complexity. [Copyright &y& Elsevier]

In the spirit of the theory of biocomplexity and of the non-linear emergent characters of ecological systems, the eco-field is a new paradigm that integrates the vision of the landscape as a neutral matrix (like a habitat) in which organisms are living, and contemporarily as a product of the human mind. Eco-field is defined a ‘cognitive field’ created by the interference between functional traits and the ‘real world’. Species-specific environmental suitability is the result of the quality of the different eco-fields and the landscape becomes a cognitive entity. The eco-field paradigm can be extended to the emergent properties of the systems. The eco-field of emergences is the geographic space in which the emergent properties appear. The eco-field of organisms and the eco-field of emergences, like results of aggregated entities, have in common the multidimensionality of landscapes, refusing the vision of landscape like a neutral geographic matrix for organisms and processes. [ABSTRACT FROM AUTHOR]

Discusses the interchanges of human society and forces of nature in the global arena, and describes the processes by which human civilization and the natural world are interrelated. Structural complexity of cultural landscapes; Functional complexity in cultural landscapes; Attributes of cultural landscapes; Biodiversity in cultural landscapes; Historical persistence and cultural gaps; The global economy and the cultural landscape economy; Ecology of modern and cultural landscapes. INSET: The ecological characteristics of cultural landscapes.

Sonotopes are the acoustic patches of a soundscape, composed by different occurrences of geophonies, biophonies, and technophonies. According an ecosemiotic perspective, ecoacoustic events (EEs) are the vehicles from the attribution of meaning to the emergent sonotopes and work as neural codes. The process of encoding is suggested to be active between the perception of sonotopes and EE detection. In Ortolano Rural Sanctuary, from a grid of 12 acoustic digital recorders (ADRs) at an average distance of 30 m each with a microphone set to receive sounds from a near acoustic field, 824,160 one-minute acoustic files were obtained from October 2017 to September 2018. From these files, using the combination of three acoustic complexity indices (ACI ft , ACI ft evenness , and ACI tf evenness), through the ecoacoustic event detection and identification (EEDI) procedure, more than 200 EEs on average per ADR were extracted during this period. The EEs were seasonally aggregated with a significant separation between fall-winter and spring-summer periods. Rain and wind were important in EE composition according to location and seasonality. The number of EEs detected from just one month to three months was 57% of the total, and the first of the nine classes of ACI ft belonged to 78% of all classes of abundance. The EEs and ACI tf similarity were not correlated with the distance between ADRs, confirming the correctness of the near-field approach to detect sounds from landscapes and EE spatial independence. The ranging capacities to distinguish distance from sound sources and to discriminate the temporal and frequential patterns of acoustic signals are some of the mechanisms that species use to detect and encode environmental acoustic complexity. Species are supposed to use EE to explore and assess the acoustic habitat and probably to obtain mental maps of the surroundings they must move around using an acoustic exploration. [ABSTRACT FROM AUTHOR]

Ecoacoustics is a recent ecological discipline focusing on the ecological role of sounds. Sounds from the geophysical, biological, and anthropic environment represent important cues used by animals to navigate, communicate, and transform unknown environments in well-known habitats. Sounds are utilized to evaluate relevant ecological parameters adopted as proxies for biodiversity, environmental health, and human wellbeing assessment due to the availability of autonomous audio recorders and of quantitative metrics. Ecoacoustics is an important ecological tool to establish an innovative biosemiotic narrative to ensure a strategic connection between nature and humanity, to help in-situ field and remote-sensing surveys, and to develop long-term monitoring programs. Acoustic entropy, acoustic richness, acoustic dissimilarity index, acoustic complexity indices (ACItf and ACIft and their evenness), normalized difference soundscape index, ecoacoustic event detection and identification routine, and their fractal structure are some of the most popular indices successfully applied in ecoacoustics. Ecoacoustics offers great opportunities to investigate ecological complexity across a full range of operational scales (from individual species to landscapes), but requires an implementation of its foundations and of quantitative metrics to ameliorate its competency on physical, biological, and anthropic sonic contexts. [ABSTRACT FROM AUTHOR]

Presents the history of thoughts surrounding the idea of integrating ecology and economics, and argues for the integrative approach to the two fields. Linear economies which focus on the maximization of production; Circular economies which focus on the production of basic products by which to sustain human life; Modern approach which is known as the ecological economics approach to sustainability, and focuses on the potential perpetuity of both economic and ecological cycles.

Forests, deserts, rivers, and oceans are filled with animal vocalizations and geological sounds. We postulate that climate change is changing the Earth's natural acoustic fabric. In particular, we identify shifts in acoustic structure that all sound-sensitive organisms, marine and terrestrial, may experience. Only upstream solutions might mitigate these acoustic changes. [ABSTRACT FROM AUTHOR]

Jérôme Sueur and colleagues introduce the acoustic components of biodiversity. [ABSTRACT FROM AUTHOR]

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]

This article presents a unifying theory of soundscape ecology, which brings the idea of the soundscape -- the collection of sounds that emanate from landscapes -- into a research and application focus. Our conceptual framework of soundscape ecology is based on the causes and consequences of biological (biophony), geophysical (geophony), and human-produced (anthrophony) sounds. We argue that soundscape ecology shares many parallels with landscape ecology, and it should therefore be considered a branch of this maturing field. We propose a research agenda for soundscape ecology that includes six areas: (1) measurement and analytical challenges, (2) spatial-temporal dynamics, (3) soundscape linkage to environmental covariates, (4) human impacts on the soundscape, (5) soundscape impacts on humans, and (6) soundscape impacts on ecosystems. We present case studies that illustrate different approaches to understanding soundscape dynamics. Because soundscapes are our auditory link to nature, we also argue for their protection, using the knowledge of how sounds are produced by the environment and humans. [ABSTRACT FROM AUTHOR]