Integrating organismal, population, and community ecology using passive acoustic sensor networks
Sound is a widespread communication mode across vertebrate and invertebrate lineages. Across these taxa, sound is used primarily in reproductive and agonistic behavioral contexts. While these signals are primarily used to convey information to conspecifics, the passive acoustic recording of these sounds can be used to establish a wide range of information in space and time of acoustically active organisms including their physiological state, behavioral state, population-level activity (e.g., reproduction), community assembly, and species interactions. Long-term recordings covering broad geographical scales can address patterns of organismal, population, and community-level change. Here, we present new, representative data from several acoustically active species to demonstrate the range of fundamental ecological questions at multiple levels of biological organization that can be addressed using passive acoustics.
Recent results from a diversity of taxa in marine and terrestrial ecosystems reveal exciting ecological insights through the use of acoustics. For two focal marine fish species in the Atlantic coast, patterns of calling activity indicate both their physiological and behavioral states. Frequency properties of these calls, determined by the contraction rate of dedicated sound producing muscles, show a positive relationship with water temperature. The onset and duration of their reproductive chorusing activity also positively correlates with water temperature. Persistent acoustic monitoring across the Atlantic coast demonstrates seasonal migration patterns of marine mammals and their interannual variation. At the community level, work in both fish and insects show how diverse species assemblages partition “acoustic space” within their communities, and occupy or compete for acoustic niches. Many of the behavioral changes observed through these long-term recordings suggest population-level responses to environmental change in both marine and terrestrial ecosystems. An integrative and comparative approach to the study of animal bioacoustics demonstrates how fundamental principles of animal ecology can be addressed through the recording and interpreting sounds in nature.