Pine processionary maximum recorded of . The species flies from May to July. "T. pityocampa" is a highly social organism. Throughout its life cycle, a pine processionary will make several shelters. The first of these are flimsy and temporary, but in the third instar, they build a permanent nest. Once their permanent nest is built, the caterpillars become foragers staying in the vicinity of the nest. The nest has no openings, so caterpillars force themselves through the layers of the shelter. The waste from the larvae's diet accumulates at the bottom of the nest. The pine processionary caterpillar is responsible for most
Natural hazard human activity. Disease is a natural hazard that can be enhanced by human factors such as urbanization or poor sanitation. Disease affecting multiple people can be termed an outbreak or epidemic. In some cases, a hazard exists in that a human-made defense against disease could fail, for example through antibiotic resistance. Each of the natural hazard types outlined above have very different characteristics, in terms of the spatial and temporal scales they influence, hazard frequency and return period, and measures of intensity and impact. These complexities result in "single-hazard" assessments being commonplace, where the hazard potential from one particular hazard