One year of acoustic data collection was completed throughout our Dr. Forest plots in Belgium, Germany, and Poland. Audio data was collected for one month in each season (summer, autumn, winter, and spring) from a total of 110 plots, which would not have been possible without the help of our colleagues at each of these sites.
Soundscapes typically show a strong daily and seasonal pattern, reflecting the activity patterns of the vocalizing communities present at those sites. In spring, dawn, and dusk choruses result from the mating activities of birds. In summer, insect stridulations dominate day and night recordings. In winter, it is typical to capture more quiet soundscapes and more wind.
After first describing the seasonal patterns in our sites, we want to analyze how these temporal patterns are influenced by forest diversity and landscape parameters. We hypothesize that higher tree diversity relates to a higher diversity of the vocalizing communities, through providing a wider range of ecological niches that they can exploit. A higher diversity of vocalizing species will result in overall higher acoustic activity. We also predict landscape parameters such as distance to the nearest road and distance to the forest edge will affect the level of anthropogenic noise we observe in our recordings.
Season patterns exist in all of our sites, such as the dawn chorus in spring or insect activity in summer; our next step is to investigate how tree diversity drives differences in these patterns. For example, is the dawn chorus more intense in plots with higher tree diversity? Is even the relatively quiet winter different among sites? Is there less wind, or more (sporadic) animal activity in a plot with a higher tree diversity? We plan to investigate all of these questions and more this year.
Some more sound examples: