Tallgrass prairies are rapidly vanishing biodiversity hotspots for native and endemic species, yet little is known regarding how spatial and temporal variation in prairie soundscapes relates to biological communities, in particular non-soniferous species composition. In this study, we coupled ecoacoustic recorders with above-ground pitfall traps across a 16,000 ha tallgrass prairie preserve to study the abundance and distribution of five burying beetle species including the highly endangered American burying beetle (Nicrophorus americanus). Given impending ecological shifts related to climate change, it is imperative to understand how the acoustic signature of an ecosystem may highlight important biological relationships between community constituents.
Results/Conclusions
We used values derived from six acoustic indices to quantify the ratio of technophony to biophony, acoustic complexity, diversity, evenness, entropy, and biological acoustic diversity to study the relationship between burying beetle abundance and the prairie soundscape. We found that associations were unique to particular indices, species, and times of day. For example, N. americanus trap rates showed a positive correlation to areas of increased acoustic complexity specifically at dawn. In addition, two diurnal beetle species showed significant correlations to all six acoustic indices used to quantify the July 2017 prairie soundscape. N. marginatus was consistently negatively correlated to higher levels of biophony, while N. tomentosus was consistently positively correlated to places with higher levels of biophony. Although both species are necrophilous burying beetles, breeding and emergence phenology and body size of N. marginatus and N. tomentosus are different such that competition for resources is minimized. Results from this study provides further evidence for niche segregation of sympatric species from the apparent segregation acoustic habitats.
Our findings suggest that abundances of ecologically important non-soniferous community constituents may be identified by parameters of an ecosystem soundscape. Identifying biologically relevant times from which to extract index values was more informative than relying on gross 24-hour averages of acoustic diversity. Finally, we show that favorable habitat for a rare necrophilous insect can be identified by the acoustic signature extracted from a short temporal window of its grassland ecosystem soundscape.