We used bird abundance data from the Netherlands and France to train random forest models, using the SDMaps package in R (Sierdsema et al., n.d.). Future scenario data was taken from future climate scenarios produced by the KNMI (Dutch Meteorological Organisation) ((KNMI, 2023) and the Dutch One Health SSPs (Dellar et al., n.d., 2024). The reference or 'current' time period used was 1991-2020. The future period was 2036-2065. Full details can be found in the accompanying article. Dellar, M., Geerling, G., Kok, K., van Bodegom, P., Schrama, S., & Boelee, E. (2024). Creating the Dutch One Health Shared Socio-economic Pathways (SSPs). Regional Environmental Change, 24, 16. https://doi.org/https://doi.org/10.1007/s10113-023-02169-1 Dellar, M., Geerling, G., Kok, K., van Bodegom, P., van der Schrier, G., Schrama, M., & Boelee, E. (n.d.). Future land use maps for the Netherlands based on the Dutch One Health Shared Socio-economic Pathways. Submitted. KNMI. (2023). KNMI National Climate Scenarios 2023 for the Netherlands. knmi.nl/klimaatscenarios Sierdsema, H., Kampichler, C., & Hallmann, C. (n.d.). Creating distribution maps from monitoring data and casual observations. Retrieved March 21, 2022, from https://www.sovon.nl/nl/content/trimmaps

We have modelled the current and future abundance and distribution of three different bird species in the Netherlands: blackbirds, mallards, and house sparrows. These are all species which are widespread in north-western Europe and which are likely to play a role in the transmission of several pathogens. We used random forest models created using the SDMaps R package. Climate, land use, and vegetative cover were all found to be important predictors. We found that the abundance of mallards and house sparrows is expected to increase in the future, while the abundance of blackbirds shows little change. These changes will likely have consequences for disease risk. By providing these future abundance maps, we are enabling detailed modelling of the future risk of disease outbreaks.

Funding provided by: Dutch Research CouncilROR ID: https://ror.org/04jsz6e67Award Number: NWA.1160.1S.210