Effects of density, species interactions, and environmental stochasticity on the dynamics of British bird communities

Our knowledge of the factors affecting species abundances is mainly based on time-series analyses of a few well-studied species at single or few localities, but we know little about whether results from such analyses can be extrapolated to the community level. We apply a joint species distribution model to long-term time-series data on British bird communities to examine the relative contribution of intra- and interspecific density dependence at different spatial scales, as well as the influence of environmental stochasticity, to spatiotemporal interspecific variation in abundance. Intraspecific density dependence has the major structuring effect on these bird communities. In addition, environmental fluctuations affect spatiotemporal differences in abundance. In contrast, species interactions had a minor impact on variation in abundance. Thus, important drivers of single-species dynamics are also strongly affecting dynamics of communities in time and space.

Automated summary

Our understanding of factors affecting species abundances is mainly based on the analysis of time-series data for a few well-studied species, but there is limited knowledge about whether these results can be applied to the community level. In this study, we used a joint species distribution model to analyze long-term time-series data on British bird communities. We found that intraspecific density dependence is the major factor influencing the structure of these bird communities, and environmental fluctuations also affect spatiotemporal variation in abundance. In contrast, species interactions have a minor impact on abundance variation. Therefore, the important drivers of single-species dynamics also strongly affect community dynamics in both time and space.