Biodiversity and Conservation

, 17:2979 | Cite as

The European spruce bark beetle Ips typographus in a national park: from pest to keystone species

  • Jörg MüllerEmail author
  • Heinz Bußler
  • Martin Goßner
  • Thomas Rettelbach
  • Peter Duelli
Original Paper


The influence of natural disturbance on biodiversity is poorly known in the intensively cultivated landscape of Europe. As an example of insect disturbance we studied effects of gaps generated by outbreaks of the spruce bark beetle (Ips typographus) on biodiversity in the area of the National Park “Bavarian Forest” and compared them with openings (e.g. meadows) created by humans in these forests. Insects were sampled using flight interception traps across twelve ecotones between edges of closed forest, six bark beetle gaps and six meadows. The diversity and species density of true bugs and of bees/wasps increased significantly from the closed stand to the edge, and continued to increase inside the openings at interior and exterior edges. Species density in saproxylic beetles also increased significantly from closed forest to opening, but only across ecotones including bark beetle gaps. Similarly, the number of critically endangered saproxylic beetles increased significantly in bark beetle gaps. Using indicator species analysis a total of 60 species were identified as possessing a statistically significant value indicating preference for one of the habitat types along the ecotones: 29 of them preferred gaps, 24 preferred meadows, three were characteristic for edges of meadows, three for edges of bark beetle gaps, but only one was typical of closed forest. Most of our results support the thesis that I. typographus fulfils the majority of criteria for a keystone species, particularly that of maintenance of biodiversity in forests. Our results emphasize the value for the study and conservation of insect diversity of the policy of non-interference with natural processes pursued in some protected areas. As a recommendation to forest management for increasing insect diversity even in commercial forest, we suggest that logging in recent gaps in medium aged mixed montane stands should aim at retention of a part of the dead wood. Planting should be avoided, to lengthen the important phase of sunlit conditions.


Bark beetles Forest edge Gaps Saproxylic beetles True bugs Bees and wasps Insect outbreak 



We thank the following persons and institutions: M. Preis and G. Sellmayer for assistance in the fieldwork, M. Preis for sorting the material, A. Liston for revising the language, Jens Esser for verification of determinations of some beetle specimens, two anonymous referees for their valuable comments, and the administration of the National Park “Bavarian Forest” for providing financial support.


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Copyright information

© Springer Science+Business Media B.V. 2008

Authors and Affiliations

  • Jörg Müller
    • 1
    Email author
  • Heinz Bußler
    • 2
  • Martin Goßner
    • 3
  • Thomas Rettelbach
    • 4
  • Peter Duelli
    • 5
  1. 1.National Park “Bavarian Forest”GrafenauGermany
  2. 2.Bavarian State Institute for ForestryFreisingGermany
  3. 3.Loricula – Agency for Canopy Research, Ecological Studies and DeterminationFronreuteGermany
  4. 4.SurbergGermany
  5. 5.Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland

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