Varroa alert service for beekeepers consists of a user interface, a prediction model, a risk assessment tool and an alert function. The user interface allows individuals participating in a crowd sourcing scheme to enter the Varroa infestation rate of their beehives, assessed according to a standardised method. The prediction model processes infestation data coming in at different points in time from different hives and predicts the current infestation rate of individual hives, sites and regions. The model considers, among other factors, growth rate, population density and mortality of Varroa mites as well as activity of honeybee colonies and control treatments applied by the beekeeper. Based on this prediction a risk analysis is performed, which triggers alerts, if infestation increases above a threshold. Alerts are posted on social networks, on the website and sent to registered users.