Climate change impacts on forest pests*

Changes in the patterns of disturbance by forest pests (insects, pathogens and other pests) are expected under a changing climate as a result of warmer temperatures, changes in precipitation, increased drought frequency and higher carbon dioxide concentrations. These changes will play a major role in shaping the world's forests and forest sector.

Insects and pathogens have been noted to respond to warming in all the expected ways, from changes in phenology and distribution to influencing community dynamics and composition. While some impacts of climate change may be beneficial in terms of protecting forest health (e.g. increase winter mortality of some insect pests due to thin snow cover; slower larval development and increased mortality during droughts), many impacts will be quite detrimental (e.g. accelerated insect development rate; range expansions of pests).

Climate change can affect forest pests and the damage they cause by:

  • directly impacting their development, survival, reproduction, distribution and spread;
  • altering host physiology and defences;
  • impacting the relationships between pests, their environment and other species such as natural enemies, competitors and mutualists.

* More detailed information, including references, can be found in our publication Climate change impacts on forest health.
last updated:  Monday, December 27, 2010