In programs of acoustic survey, the amount of data collected and the lack of automatic routines for their classification and interpretation can represent a serious obstacle to achieving quick results. To overcome these obstacles, we are proposing an ecosemiotic model of data mining, ecoacoustic event detection and identification, that uses a combination of the acoustic complexity indices and automatically extracts the ecoacoustic events of interest from the sound files. These events may be indicators of environmental functioning at the scale of (...) individual vocal species, the acoustic community, the sound marks, or the soundscape. The EEDI model is represented by three procedural steps: 1) selecting acoustic data according to environmental variables, 2) detecting the events by creating an ecoacoustic event space produced by plotting ACIft and its evenness, 3) identifying events according to the level of correlation between the acoustic signature of the detected events and an ad hoc library of previously identified events. The EEDI procedure can be extensively used in basic and applied research. In particular, EEDI may be used in long-term monitoring programs to assess the effect of climate change on individual vocal species behavior, population, and acoustic community dynamics. The EEDI model can be also used to investigate acoustic human intrusion in natural systems and the effect in urban areas. (shrink)

Acoustic codes assure the intra and interspecific communication of vocal animals. They are composed by a sequence of nominal entities and by magnitude modulation confirming in such a way contemporarily a behavioural and ecological nature. The acoustic codes find evidence in the acoustic niche hypothesis by which species in order to reduce interspecific competition occupy a restricted portion of the available frequencies modulating very precise acoustic cues . Their evolution, like other aspect of biology, is under control of the environmental (...) conditions assuming the more favourable configurations. These nominal entities respond also to the amount of energy by which are emitted allowing to the eavesdropping individuals to range the distance at which a potential competitor is broadcasting a signal. Environmental alterations, especially if of anthropogenic origin, can produce severe consequence of the acoustic codes that in turn may affect the prey–predator balance and the complexity of communities. In fact acoustic codes under an environmental constraint like human noise intrusion can be modified in order to reduce a masking effect, demonstrating their phenological plasticity. The new ecological discipline of soundscape ecology offers the possibility to investigate the nature and the evolution of the acoustic codes in different environmental conditions. (shrink)

The soundscape, which is defined as the entire acoustic environment of an area, is a relevant biosemiotic ingredient of environmental complexity. It is composed of geophonies, anthrophonies, and biophonies where, in temperate biomes, birds are the major producers of the latter. The soundscape is heterogeneous in terms of space and time, and is affected by landscape features such as vegetation cover. It also operates as a communication network in which intra- and inter-specific interactions create a complex, eavesdropping-broadcasting network, namely, the (...) soundtope. This acoustic context provides public information for tracking resources like territory, mates, food, safety, and roosting sites and it can be considered a multifunctional eco-field. The Acoustic Complexity Index is a new metric that is used to efficiently process the sound files that, when collected by sampling matrixes, return by interpolation the spatial distribution of a soundscape. High quality soundscapes are sought to guarantee the biosemiotic mechanisms among species, but polluted conditions degrade and mask biophonies, thus reducing communication efficiency, with severe consequences for both individual and collective fitness. Preserving high quality soundscapes is therefore an important conservation issue and a target to aim for if we are to assure animal and human wellbeing. (shrink)

Capturing information means for every organism acquiring knowledge about the living and not living objects that exist in its surroundings. In this way, the “historical” concept of Umwelt, as a subjective surrounding has been recently integrated in the theory of landscape ecology where a landscape is not only a geographical entity but also a cognitive medium. The landscape may be considered a semiotic context used by the organisms to locate resources heterogeneously distributed in space and time. In particular, inside a (...) landscape there are different eco-fields defined as spatial arrangements of objects carrier of meaning that organisms utilize to track resources. Along this epistemic path the sonic component of the landscape is an important carrier of information commonly used by the majority of animal species to managing many vital functions. In particular birds, which are animals with a complex system of acoustic communication, seem to organize acoustic centers for public information. These sonic patterns (soundtopes) are characterized by a great variability in space and time and function like a special eco-field that allows species to share information about the status of resources and the dynamics of populations. The availability of such public information avoids a deeper and more expensive exploration of the environment to assess its quality. (shrink)