Return of the moth: rethinking the effect of climate on insect outbreaks. ...

• Main Authors: Büntgen, Ulf, Liebhold, Andrew, Nievergelt, Daniel, Wermelinger, Beat, Roques, Alain, Reinig, Frederick, Krusic, Paul J, Piermattei, Alma, Egli, Simon, Cherubini, Paolo, Esper, Jan
• Format: Article in Journal/Newspaper
• Language: English
• Published: Springer Science and Business Media LLC 2020
• Subjects: Dendroecology; European Alps; Insect outbreaks; North Atlantic Oscillation; Population cycles; Zeiraphera diniana or griseana; Animals; Climate Change; Disease Outbreaks; Larix; Moths; Population Dynamics; North Atlantic; North Atlantic oscillation
• Online Access: https://dx.doi.org/10.17863/cam.47925; https://www.repository.cam.ac.uk/handle/1810/300848

The sudden interruption of recurring larch budmoth (LBM; Zeiraphera diniana or griseana Gn.) outbreaks across the European Alps after 1982 was surprising, because populations had regularly oscillated every 8-9 years for the past 1200 years or more. Although ecophysiological evidence was limited and underlying processes remained uncertain, climate change has been indicated as a possible driver of this disruption. An unexpected, recent return of LBM population peaks in 2017 and 2018 provides insight into this insect's climate sensitivity. Here, we combine meteorological and dendrochronological data to explore the influence of temperature variation and atmospheric circulation on cyclic LBM outbreaks since the early 1950s. Anomalous cold European winters, associated with a persistent negative phase of the North Atlantic Oscillation, coincide with four consecutive epidemics between 1953 and 1982, and any of three warming-induced mechanisms could explain the system's failure thereafter: (1) high egg mortality, (2) ...