The present study is the first modeling effort at a global scale to predict habitat suitability of fall armyworm (FAW), Spodoptera frugiperda and its key parasitoids, namely Chelonus insularis, Cotesia marginiventris,Eiphosoma laphygmae,Telenomus remus and Trichogramma pretiosum, to be considered for biological control. An adjusted procedure of a machine-learning algorithm, the maximum entropy (Maxent), was applied for the modeling experiments. Model predictions showed particularly high establishment potential of the five hymenopteran parasitoids in areas that are heavily affected by FAW (like the coastal belt of West Africa from Côte d’Ivoire (Ivory Coast) to Nigeria, the Congo basin to Eastern Africa, Eastern, Southern and Southeastern Asia and some portions of Eastern Australia) and those of potential invasion risks (western & southern Europe). These habitats can be priority sites for scaling FAW biocontrol efforts. In the context of global warming and the event of accidental FAW introduction, warmer parts of Europe are at high risk. The effect of winter on the survival and life cycle of the pest in Europe and other temperate regions of the world are discussed in this paper. Overall, the models provide pioneering information to guide decision making for biological-based medium and long-term management of FAW across the globe.

The pinewood nematode (PWN) is one of the worst tree-killing exotic pests in East-Asian countries. The first European record of establishment in Portugal in 1999 triggered extensive surveys and contingency plans for eradication in European countries, including immediate removal of large areas of conifer host trees. Using Norway as an example, we applied a simulation model to evaluate the chance of successful eradication of a hypothetical introduction by the current contingency plan in a northern area where wilting symptoms are not expected to occur. Despite a highly variable spread of nematode infestations in space and time, the probability of successful eradication in 20 years was consistently low (mean 0.035, SE 0.02). The low success did not change significantly by varying the biological parameters in sensitivity analyses (SA), probably due to the late detection of infestations by the survey (mean 14.3 years). SA revealed a strong influence of management parameters. However, a high probability of eradication required unrealistic measures: achieving an eradication probability of 0.99 in 20 years required 10,000 survey samples per year and a host tree removal radius of 8,000 m around each detection point.

Skarveit, J. and Gjerde, I. 2003. The canopy arthropods of old and mature pine Pinus syl6estris in Norway. -Ecography 26: 490-502.We fogged 24 trees in two pine dominated forests in Norway with a synthetic pyrethroid in order to compare the canopy-dwelling fauna of arthropods between costal (Kvam) and boreal (Sigdal) sites and between old (250-330 yr) and mature (60-120 yr) trees at Sigdal. Almost 30 000 specimens were assigned to 510 species; only 93 species were present at both sites. Species diversity, as established by rarefaction, was similar in old and mature trees. However, the number of species new to Norway (including nine species new to science) was significantly higher in the old trees. We suggest that the scarcity of old trees, habitat heterogeneity and structural differences between old and mature trees may explain these patterns. Productivity and topographic position at the site of growth explained the between-tree variation in species occurrence for the more abundant species, which were mainly Collembola and Oribatida. Species diversity was similar at the boreal and coastal sites, but there were clear differences in species composition.K. H. Thunes (karl.thunes@skogforsk.no) and I. Gjerde, Norwegian Forest Research Inst.,

Sporophores of Piptoporus betulinus (Bull. ex Fr.) Karst. and Fomes fomentarius (L. ex Fr.) Kickx were collected during March to December 1991 from five different West Norwegian forests. Their beetle faunas are described in detail. Various factors contribute in the decomposing process of the sporophore, and the faunas change considerably during this process. The host specificity of the obligatory polypore inhabitants is probably determined by other factors besides the polypore itself, because the faunas change between forests of different productivity classes and with different tree compositions. Furthermore, the almost vicariant distribution of Cis alter and C. jacquemarti could best be explained by interspecific competition. A simple phenology for Cis bidentatus, C. alter, C. lineatocribatus, C. jacquemarti, Leptusa pulchella, L. fumida and L. ruficollis is given.