Abstract

Frequent bark beetle outbreaks cause biome-scale impacts in boreal and temperate forests worldwide. Despite frequent interceptions at ports of entry, the most aggressive bark beetle species of Ips and Dendroctonus in North America and Eurasia have failed to establish outside their original home continents. Our experiments showed that Ips typographus can breed in six North American spruce species: Engelmann spruce, white spruceA Sitka spruce, Lutz spruce, black spruce and red spruce. This suggests that differences between the Eurasian historical host and North American spruce species are not an insurmountable barrier to establishment of this tree-killing species in North America. However, slightly diminished quality of offspring beetles emerged from the North American spruces could reduce the chance of establishment through an Allee effect. The probabilistic nature of invasion dynamics suggests that successful establishments can occur when the import practice allows frequent arrivals of non-indigenous bark beetles (increased propagule load). Model simulations of hypothetical interactions of Dendroctonus rufipennis and I. typographus indicated that inter-species facilitations could result in more frequent and severe outbreaks than those caused by I. typographus alone. The potential effects of such new dynamics on coniferous ecosystems may be dramatic and extensive, including major shifts in forest structure and species composition, increased carbon emissions and stream flow, direct and indirect impacts on wildlife and invertebrate communities, and loss of biodiversity.

Keywords

Species introduction; Invasive species; Ips; Dendroctonus; Coniferous forests; Outbreak frequency

Published in

Biological Invasions
2011, Volume: 13, number: 5, pages: 1151-1164
Publisher: SPRINGER

SLU Authors

• Långström, Bo

  • Department of Ecology, Swedish University of Agricultural Sciences
    

Sustainable Development Goals

Protect, restore and promote sustainable use of terrestrial ecosystems, sustainably manage forests, combat desertification, and halt and reverse land degradation and halt biodiversity loss


UKÄ Subject classification

Forest Science
Ecology


Publication identifier

DOI: https://doi.org/10.1007/s10530-011-9957-2

Permanent link to this page (URI)

https://res.slu.se/id/publ/57733