Population ecology and natural control of the oak processionary moth

This project aims to compare the behaviour of oak processionary moth populations in open and woodland habitats, to predict when and where damaging infestations are most likely to occur and to identify which factors (microclimate, natural enemies or host phenology) are most important in determining the moth’s abundance.

Research objectives

Specific research objectives are to:

  • develop standardised methods for assessing OPM populations
  • analyse variation in OPM population numbers in relation to habitat type, microclimate, the prevalence and diversity of naturally occurring parasitoids and predators, and variation in tree size and phenology
  • develop molecular techniques for identifynig parasitoids and predators of OPM and use these techniques to quantify parasitism rates
  • construct and analyse ecological networks of natural enemies that attack OPM and other moth species living in the same habitats

Results so far

Fieldwork carried out in 2014 indicates significant differences in OPM populations between habitat types. Samples of OPM larvae and pupae collected during the summer are being analysed over the autumn and winter period to identify parasitoids and estimate mortality rates.


The project started in 2014 and will end in 2017.

Studies on OPM populations in different habitats and factors that influence abundance are being carried out as part of a PhD studentship with the University of Southampton.

Molecular techniques to identify parasitoids of OPM and to quantify their impact are being developed by a research post at the University of Hull

Related Resources

Forestry Commission web pages on OPM

Pest Risk Analysis of Oak Processionary Moth

FR resources pages on OPM


Dr Nigel Straw

Funders and partners

This research project is funded by Forestry Commission England as part of the enhanced OPM control programme, which began in 2013 http://www.forestry.gov.uk/forestry/INFD-9Q5HNT

The programme is supported by Defra.

Forestry Commission policy
This research underpins the evidence base for the delivery of healthy and resilient forests and wider ecosystems which is part of the Tree Health and Plant Biosecurity Action Plan

Current action against OPM