Studies on the exposition and temperature of nests of Thaumetopoea pityocampa (Den. & Schiff.) (Lep., Thaumetopoeidae) in Greece

Abstract

Studies on nests of the pine processionary caterpillar were carried out in different parts of Greece in the years 1985 to 1988. Most of the nests could be found at the southeast, south and southwest of pine trees. Deviations in the distribution could be due to the slope of forests and a high population pressure. Registering of temperature data verified that the inner temperature of the caterpillar nests could rise quite high. Such a warming is clearly dependent on the intensity of the insolation and the thickness of the nest webs. The biogenic heat production has not a significant role.

Climate change and the incidence of a forest pest in Mediterranean ecosystems: can the North Atlantic Oscillation be used as a predictor?

“…The zones dominated by this pine species have a mild climate in winter, conducive to PPM development irrespectively of NAO phases. Pines in these areas need to be resistant to PPM because its incidence is chronic, and predators and parasitoids probably have more diverse and developed populations than in high-mountain sites, and it is known that stone pine is the species least susceptible to the PPM (Démolin 1969b;Avtzis 1986;Breuer et al 1989;Devkota and Schmidt 1990;Tiberi et al 1999). As a result, the defoliation dynamics in the woodland stands dominated by stone pine differ sharply from those of more palatable pines (black or Scots pine, Fig.…”

“…This is a key factor determining the outbreak capacity of PPM, as low winter temperatures heavily determine the larval survival of this insect (e.g. Breuer et al 1989;Battisti et al 2005;Buffo et al 2007). Several studies have found, as a consequence of the general rise in temperatures, a progression in latitude and/or altitude with respect to the previous distribution of the pest, as well as an increase in outbreak severity (Hódar et al 2003;Battisti et al 2005Battisti et al , 2006Robinet et al 2007).…”

Larval development of Thaumetopoea pityocampa (Den. & Schiff.) (Lep., Thaumetopoeidae) from Greece as influenced by different host plants under laboratory conditions1

“…Different species of the pines serve as the host plants to these polyphagous voracious feeders. In Kalogria (Greece), P. halepensis is overwhelmingly preferred to P. pinea ( BREUER et al 1989) where both stands occur together. In the eastern Mediterranean forests, the three close relatives of pines P. eldarica, P. brutia and P. halepensis are attacked in decreasing magnitude by T.…”

Effects of climate on pine processionary moth fecundity and on its egg parasitoids

“…As tent temperatures are always 0.5–9°C higher than air temperatures (Breuer et al. ), we assume that, in our study site, tent temperatures were above 6°C when the preceding day's maximum air temperatures were close to 0°C Secondly, we included the average minimum daily temperatures, which had been suggested by Buffo et al. () as a suitable index for PPM winter feeding.…”

“…Firstly, we examined the number of days with a minimum temperature above 0°C, which is the lowest PPM feeding limit (Huchon and D emolin 1970) with temperatures inside the tent reaching at least 6°C the preceding day (Battisti et al 2005). As tent temperatures are always 0.5-9°C higher than air temperatures (Breuer et al 1989), we assume that, in our study site, tent temperatures were above 6°C when the preceding day's maximum air temperatures were close to 0°C Secondly, we included the average minimum daily temperatures, which had been suggested by Buffo et al (2007) as a suitable index for PPM winter feeding. In addition, another CIV, the average minimum temperatures for the October-March period, indicated by Robinet et al (2007) as the best predictor of the number of PPM feeding days, were also evaluated.…”