Invasive species

 

Invasive species

 

Invasive exotic insects can cause substantial damage to trees and the environment. The extensive trade with wooden products represents a high risk of transferring forest pests to new territories. In some cases, the damage is greater in the introduced range than in the native range of the pest. Increasing global trade of timber and frequent use of wood packaging materials like pallets, crating, and dunnage, have provided important pathways for the introduction of forest pests worldwide. The increasing import of wood chips for bioenergy production represents a potential introduction pathway for harmful organisms.

Our research is aimed at predicting the effects of forest pest introductions and reducing the risk of spread and establishment of such species. Because direct experiments with introduced species are too dangerous, we most often use a combination of data analysis and modelling. Once alien pest species have become established in their new habitats, they may be extremely difficult to eradicate, and the costs of damages and control programmes may be very high. Thus, it is of particular interest to learn what management efforts are useful for stopping the establishment and spread of new forest pests. Special attention is given to the most damaging taxa that may have biome-wide effects, such as bark beetles and the pinewood nematode.

 

International publications

 

Flø, D., Norli, H.R, Økland, B. and Krokene, P. 2018. Successful reproduction and pheromone production by the spruce bark beetle in evolutionary naïve spruce hosts with familiar terpenoid defenses. Agricultural and Forest Entomology DOI: 10.1111/afe.12280. LINK

 

Flø, D., Krokene, P., Økland, B. 2015. Invasion potential of Agrilus planipennis and other Agrilus beetles in Europe: import pathways of deciduous wood chips and MaxEnt analyses of potential distribution areas. EPPO Bulletin 45 (2), 259–268. PDF

 

Flø, D., Krokene, P., Økland, B. 2014. Importing deciduous wood chips from North America to northern Europe – the risk of introducing bark- and wood-boring insects. Scandinavian Journal of Forest Research. 29(1): 77-89. PDF

 

Økland, B., Haack, R.A. & Wilhelmsen, G. 2012. Detection probability of forest pests in current inspection protocols - A case study of the bronze birch borer. Scandinavian Journal of Forest Research 27: 285-297. PDF

Bergseng, E., Økland, B., Gobakken, T., Magnusson, C., Rafoss, T. and Solberg, B. 2012. Costs of a pest invasion contingency plan – the case of Pine Wood Nematode in Norway. Scandinavian Journal of Forest Research 27: 337-349. PDF

Økland, B., Erbilgin, N., Skarpaas, O. and Christiansen, E. 2011. Inter-species interactions and ecosystem effects of non-indigenous invasive and native tree-killing bark beetles. Biological Invasions. 13(5): 1151-1164. PDF

Økland B, Skarpaas O, Schroeder M, Magnusson C, Lindelöw Å, Thunes K. 2010. Is eradication of the pinewood nematode (Bursaphelenchus xylophilus) likely? An evaluation of current contingency plans. Risk Analysis 30(9): 1424-1439. PDF

Økland, B. Skarpaas, O. & Kausrud, K. 2009. Threshold facilitations of interacting species. Population Ecology 51: 513-523. PDF

Skarpaas, O. & Økland, B. 2009. Timber import and the risk of forest pest introductions. Journal of Applied Ecology 46: 55-63. PDF

Johnson D.M., A.M. Liebhold, K. Kausrud & B. Økland. 2007. The dispersal paradox: Are good dispersers poor invaders? Ecological Society of America Annual Meeting, August 5-10, San Jose, California. LINK

Often, A., Stabbetorp, O. & Økland, B. 2006. The role of imported pulpwood for the influx of invasive plants to Norway. Norwegian Journal of Geography 60(4): 295-302.

Reports and popular scientific publications

Sundheim, L., Flø, D., Magnusson, C., Rafoss, T., Solheim, H. & Økland, B. 2013. Import of deciduous wood chips from eastern North America – pathway-initiated risk characterizations of relevant plant pests. Opinion of the Panel on Plant Health of the Norwegian Scientific Committee for Food Safety. PDF

 

Sundheim, L., Flø, D., Rafoss, T. & Økland, B. 2012. The EPPO PRA for Agrilus anxius: Assessment for Norwegian conditions. Opinion of the Panel on Plant Health of the Norwegian Scientific Committee for Food Safety. PDF

 

Sundheim, L., Flø, D., Rafoss, T. & Økland, B. 2012. Risikovurdering av planteskadegjøreren Anoplophora chinensis for Norge. Opinion of the Panel on Plant Health of the Norwegian Scientific Committee for Food Safety. [in Norwegian] PDF

 

Økland, B., Børja, I. and Often, A. 2012. Føre var eller aldri klar. Chronicle in VG, 17 June 2012. PDF

Økland, B., Børja, I., Often, A., Solheim, H. & Flø, D. 2012. Import av tømmer og andre treprodukter som innførselvei for fremmede insekter, sopp og planter - trendanalyse av importstatistikk. Rapport fra Skog og landskap 10/12: 137 s. PDF

Økland, B., Dalen, L.S. and Venn, K. 2011. Risiko for stor skade på skogen. Chronicle in Dagens Næringsliv, 1 February 2011. PDF

Sundheim, L., Økland, B., Magnusson, C., Solberg, B., Rafoss, T. 2010. Pest risk assessment of the Pine Wood Nematode (PWN) Bursaphelenchus xylophilus in Norway – Part 2. Opinion of the Plant Health Panel of the Scientific Committee for Food Safety, 08/906. PDF

Bergseng, E., Økland, B., Gobakken, T., Magnusson, C., Rafoss, T. and Solberg, B. 2010. Report on the economic impacts of the Norwegian contingency plan for Pine Wood Nematode (PWN) Bursaphelenchus xylophilus. Report from VKM to Mattilsynet. PDF

Økland 2009. Tredrepende barkbiller i Europa og Nord-Amerika. Glimt 06/09.

Sundheim, L., Økland, B., Magnusson, C., Solberg, B., Rafoss, T. 2008. Pest risk assessment of the Pine Wood Nematode (PWN) Bursaphelenchus xylophilus in Norway – Part 1. Opinion of the Plant Health Panel of the Scientific Committee for Food Safety, 18.09.08.

Økland, B. & Skarpaas, O. 2008. Draft pest risk assessment report on the small spruce bark beetle, Ips amitinus. Commissioned Report from Norwegian Forest and Landscape Institute 10/08: 20 pp. PDF

Økland, B., Skarpaas, O., Kausrud, K., Stenseth, N.C., Erbilgin, N. 2007. Spatiotemporal dynamics of introduced bark beetles. pp. 89-93 in Evans, H. and Oszako, T. (eds) Alien invasive species and trade. IUFRO Unit 7.03.12 Monograph. PDF

Kausrud, K., Økland, B., Skarpaas, O., Stenseth, N.C. & Erbilgin, N. 2007. Spatiotemporal dynamics of invasive bark beetles - modeling dispersal strategies. USDA Interagency Research Forum USDA General Technical Report-NRS-Proceedings 28: p. 42. PDF

Økland, B & Skarpaas, O. 2006. Risikovurdering av Ips amitinus ved tømmerimport - sannsynlighet for introduksjon og effekt på barkbilleutbrudd. Oppdragsrapport fra Skog og landskap 07/2006 PDF

Økland, B., Kvamme, T. & Wollebæk, G. 2005. Ny barkbilleart funnet overvintrende. Skogeieren 10/2005: 30-31 PDF

Økland, B. (ed.) 2004. Sopp, insekter og karplanter innført til Norge ved tømmerimport fra Russland og Baltikum. Aktuelt fra skogforskningen 5/2004: 1-24. PDF

Økland, B., Kvamme, T. & Thunes, K. 2004. Tømmerimport og innføring av insekter. Glimt fra skogforskningen 2-2004: 1-2. PDF

Kvamme, T., Thunes, K. & Økland, B. 2003. Insekter innført ved tømmerimport. In: Thunes, K. (ed.) Insekter, sopp og karplanter innført til Norge ved tømmerimport fra Russland og Baltikum 2002. Aktuelt fra skogforskningen 4/2003: 1-24.

 

Økland, B., Kvamme, T. & Thunes, K. 2003. Kan nye insekter introduseres med importtømmer? Aktuelt fra Skogforsk 6/03: 9-10.

 

Økland, B. 2002 (ed.). Insekter, sopp og karplanter innført til Norge ved tømmerimport fra Russland og Baltikum. Aktuelt fra skogforsk 2/02: 1 – 24.

 

 

Biodiversity

 

Forest management has a strong influence on the biodiversity of invertebrates, and the effects of similar management practice differ significantly for the various invertebrate taxa. There is a taxonomic bias in conservation research making insects, and especially less charismatic insect groups, underrepresented compared to their large species numbers.

 

Most woodland pastures were abandoned 40-80 years ago, and have been invaded by other trees during secondary succession. A more recent land use, thinning and harvesting of tops and branches for biofuel production, may possibly lead to a new region-wide transformation of qualities in overgrown oak-pasture lands in southern Scandinanvia. The relatively fast changes of the temperate forest landscapes present a challenge to biodiversity management (Götmark et al. 2009). A project leaded from the University of Göteborg examined effects on biodiversity in various organism groups: vascular plants, lichens, bryophytes, fungi, molluscs, saproxylic beetles (Franc et al. 2007), and mycetophilids (Kurina et al. 2005, Økland et al. 2005, 2008).

 

The coniferous forests constitute a large portion of the northern forest ecosystems and are strongly influenced by management due to their importance for forest economy. In addition to amount of dead wood, the diversity of saproxylic beetles in spruce forests is determined by the spatial distribution of dead wood (Økland et al. 1996), the composition of qualitatively different saproxylic habitats (Økland 1995, Komonen et al. 2004), stand structure (Hågvar & Økland 1997), and canopy cover (Økland 2002). Mycetophilids are in particular species-rich in boreal forests (Økland et al. 2005). These dipteran insects are frequently observed in dark and closed spruce forests, and they are often found in moist holes or under root jars, especially during dry periods. Large-scale logging appears to be unfavourable for mycetophilids (Økland 1994), and their species richness is increasing with the percentage area of oldgrowth forest in the landscape (Økland 1996).

Publications

Hågvar, S., Amundsen, T. & Økland, B. 2014. Mites of the genus Carabodes (Acari, Oribatida) in Norwegian coniferous forests: occurrence in different soils, vegetation types and polypore hosts. Scandinavian Journal of Forest Research 29(7), 629-638. PDF

 

Götmark, F., Nordén, B., Franc, N., Paltto, H., von Proschwitz, T., Økland, B. & Monrad Jensen, A. 2009. Naturvårdsgallring – vad är det? Biodiverse 1-2009: 20. PDF [in Swedish]

 

Økland, B., Götmark, F. & Nordén, B. 2008. Oak woodland restoration: testing the effects on biodiversity of mycetophilids in Sweden. Biodiversity & Conservation 17(11): 2599–2616. PDF

Økland, B., Götmark, F., Nordén, B., Franc, N., Kurina, O., Polevoi, A. 2005. Regional diversity of mycetophilids (Diptera: Sciaroidea) in Scandinavian temperate forests. Biological Conservation 121(1): 9-20. PDF

Kurina, O., Polevoi, A., Götmark, F., Økland, B., Frank, N., Norden, B. & Hedmark, K. 2005. Fungus gnats (Diptera: Sciaroidea excl. Sciaridae) in the Swedish boreonemoral forests. - Studia Dipterologica, 11 (2004), Heft 2: 471 - 488.

Franc, N., Götmark, F., Økland, B., Nordén, B. & Paltto, H. 2007. Factors and scales potentially important for saproxylic beetles in temperate mixed oak forest. Biological Conservation 135: 86-98. PDF

 

Komonen, A, Jonsell, M. & Økland, B. 2004. Insect assemblage associated with the polypore Fomitopsis pinicola: a comparison across Fennoscandia. Ent. Fenn. 15: 102-112.

 

Økland, B. 2002. Canopy cover favours sporocarp-visiting beetles in spruce forests. Norw. J. Entomol. 49: 29-39. PDF

 

Økland, B. 2000. Management effects on the decomposer fauna of Diptera in spruce forests. Studia Dipterologica 7(1): 213-223.

 

Hågvar, S. & Økland, B. 1997. Saproxylic beetle fauna associated with living sporocarps of Fomitopsis pinicola (Fr.) Karst. in four spruce forests with different management histories. Fauna norv. Ser. B 44: 95-105. PDF

 

Økland, B., Bakke, A., Hågvar, S. and Kvamme, T. 1996. What factors influence the diversity of saproxylic beetles? A multiscaled study from a spruce forest in southern Norway. Biodiversity and Conservation 5: 75-100. PDF

 

Økland, B. 1996. A comparison of three methods of sampling saproxylic beetles. European Journal of Entomology 93: 195-209.

 

Økland, B. 1996. Unlogged forests: Important sites for preserving the diversity of mycetophilids (Diptera: Sciaroidea). Biological Conservation 76: 297-310. PDF

 

Økland, B. 1995. Insect fauna compared between six polypore species in a southern Norwegian spruce forest. Fauna norv. Ser. B. 42: 21-26. PDF

 

Økland, B. 1994. Mycetophilidae (Diptera), an insect group vulnerable to forestry? A comparison of clearcut, managed and semi-natural spruce forests in southern Norway. Biodiversity and Conservation 3: 68-85. PDF