Evaluating the impact of extreme climatic events
The pine procession moth (Thaumetopoea pityocampa) is considered among the most important limiting factors for both growth and survival of pine forests in southern Europe and Mediterranean countries. This is because this species of moth is an important pine defoliator whose larvae feed in colonies during the winter. Recently the species has exhibited a tendency to expand its range to upper latitude and elevation. This is likely due to the effects of global warming. Therefore it is important to reconsider current pest management strategies since the traditional methods used in core areas should be assessed before they can be applied in expansion areas. Climatic anomalies can produce or accelerate geographic range expansions of species limited by temperature or other climatic variables. Expansions like this are usually short term since the climatic conditions that prevail end up causing the populations to become extinct. However, a recent rapid shift of range limit in the summer heat wave of 2003 in southern Europe could end up being permanent as well as having crucial implications on species range dynamics overall. That summer the winter pine processionary moth (Thaumetopoea pityocampa), exhibited remarkable expansion to high elevation pine stands in the Italian Alps. During the winter, the moth is limited in its distribution due to temperature. However, the past three decades, warmer winters have caused a slow yet signification expansion of the moth's latitudinal and altitudinal range. According to the results of the conducted experiment it was concluded that the colonies established at extreme sites survived the winter and produced offspring in 2004. The advantages of the findings are that a general model was constructed which can predict the expansion of the moth at range edge and take extreme climatic conditions into consideration. Since this is a rather unique case, it may be used as a reference model in numerous studies to come. Partners are seeking collaboration from parties interested the evaluation of the role extreme climatic events have on insect pests.