Aim: To develop an approach to model the spatial dynamics of emerald ash borer Agrilus planipennis (Coleoptera: Buprestidae) in European Russia. This tree-killing pest was detected in Moscow 15 years ago and began to spread, posing a threat to ashes all over Europe. The aim was to determine its probable current range and to evaluate the probability of its dispersal to neighboring countries within the next 5 years.
Location: Cities and transport hubs of European Russia and neighboring countries. Ash trees in this region occur mainly in urban plantations and along highways.
Methods: Pairwise distances between all locations were used as the main parameter determining the probability of pest spread. For each location, the probability of detection of A. planipennis was calculated using three simulation recurrent models of long-distance dispersal. Parametrization was made by comparison with results of surveys in 2003-2015. Field data on the range of A. planipennis in 2016-2017 were mapped and used for model verification. A prognosis of spread of the pest by 2022 was made.
Results: A model based on fat-tailed kernel corresponds to both negative and positive results of surveys. According to the model, the current range is likely to be restricted to Russia, but probability of detection of the pest in the east of Belarus, Ukraine, Estonia, Latvia, and Lithuania by 2022 is 15%-40%.
Main conclusions: The forestry services of neighboring countries probably have about 5 years to prepare for the invasion of this pest, but regular surveys are necessary, since the pest can appear at any time. The case considered shows that the simple approach based on a fat-tailed kernel and just one parameter-pairwise distance between cities-can be used for modeling long-distance dispersal of alien pests of urban plantations.
Keywords: Agrilus planipennis; ash pest; biological invasions; emerald ash borer; simulation model.