Generic Model to Predict the Outbreak of Insects in European Forests

Insect pests are one of the major threats to forests. Although invasive species cause more and more impacts, native species could also become real pests. The population dynamics of insects relies on several factors, going from weather to stand conditions. Due to global change, insects could face conditions they have never encountered, leading to unusual population outbreaks. Forest managers need to consider these possible emergent pests. However, the biology of these new pests is generally poorly described and predicting insect outbreaks is thus very challenging. In this context, we have developed a generic model of emergence to describe local outbreaks. This model describes the probability of occurrence of an outbreak at a given time and at a given area, based on several conditions (34 variables). It has been built and parametrized on different orders of European forest pests. This parametrization allows obtaining species profiles that can be used as a baseline to make predictions even if poor data are available on the pest, to ensure the genericity of the model. This is to our knowledge the very first generic outbreak model that has been developed so far. This model was coded in R and a user-friendly version using a shiny app was developed. In this work, we are going to present the model and its validation.