How Can Global Change Affect Insect Population Dynamics in Mediterranean Ecosystems? A Case Study with Pine Shoot Beetle and Pine Processionary Moth

Abstract

Many insect species are able to cause important damage in agriculture, forestry and human health due to their ability to feed on plants and animals tissues or transmit fungi and other diseases. Entomologists have long recognised that periods of atypical weather conditions, such as drought, excessive precipitation or unusually hot or cold weather, have great impact on insect development. Understanding the effects of climate on ecological processes has become increasingly important in entomological research as a result of global warming, which appears to be affecting their geographic ranges and population dynamics. In Mediterranean ecosystems, pine shoot beetle, Tomicus destruens Woll, and pine processionary moth, Thaumetopoa pityocampa (Denis & Schiff), are examples of species that origin problems to man. Tomicus destruens is a phytophagus insect responsible for several damages on maritime pine (Pinus pinaster Aiton) stands during its feeding on needles and its capacity to inoculate fungi and other decaying biotic agents. Thaumetopoea pityocampa is also responsible for damages in P. pinaster stands and can provoke strong allergic reactions due the presence of urticains hairs. Both species have a physiological response to the temperature variation, which is observed in the life cycle duration and in the mortality rate. The present study aims to highlight the effect of global change/global warming in the bioecology of those Mediterranean species and their implication in forest productivity and human health.