Can the non-native ambrosia beetle Xylosandrus germanus withstand an unusually cold winter in the West Carpathian forest in Central Europe?

Authors: DZURENKO, MAREK - Technical University In Zvolen; KULFAN, J - Slovak Academy Of Sciences; GALKO, J - National Forest Centre; HOLEC, J - Slovak Hydrometeorological Institute; SANIGA, M - Slovak Academy Of Sciences; ZUBRIK, M - National Forest Centre; Ranger, Christopher; ZACH, PETER - Slovak Academy Of Sciences

Submitted to: Folia Oecologica
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/1/2021
Publication Date: 12/29/2021
Citation: Dzurenko, M., Kulfan, J., Galko, J., Holec, J., Saniga, M., Zubrik, M., Ranger, C.M., Zach, P. 2021. Can the non-native ambrosia beetle Xylosandrus germanus withstand an unusually cold winter in the West Carpathian forest in Central Europe? Folia Oecologica. 49(1):1-8. https://doi.org/10.2478/foecol-2022-0001.
DOI: https://doi.org/10.2478/foecol-2022-0001

Interpretive Summary: The exotic ambrosia beetle Xylosandrus germanus has become established in Slovakia. The exceptionally cold winter of 2016/2017 provided a rare oportunity to assess whether or not X. germanus can resist low winter temperatures in the forests of the Western Carpathians in Slovakia, Central Europe, where it was first recorded in 2010. We compared trap captures of this species before and after the respective cold winter. Ethanol-baited traps were first deployed during peak flight activity of X. germanus from May 2016 – June 2016, and then deployed again from May 2017 – June 2017. Traps were deployed in 24 oak (Quercus spp.) dominated forest stands within two habitats consisting of a warm, dry southern area, and a moderately warm, moderately humid central area. Dispering females of X. germanus were recorded in all surveyed stands before and after the cold winter temperatures experience within the region in 2016/2017. Trap captures of X. germanus decreased in the southern area following the excessively low winter temperatures, but remained unchanged it the central area. Our results suggest X. germanus can withstand adverse winter weather in oak forests within altitudes between 171 and 450 m a.s.l. with varying success depending on the area and extremeness of the winter weather. Long-term field studies combined with cold hardiness experiments are needed to determine the causal effects of freezing air temperatures and other factors on the overwintering success of X. germanus in forest ecosystems.

Technical Abstract: The ability of a non-native species to withstand adverse weather conditions is indicative of its successful establishment in a newly colonized area. The exceptionally cold winter of 2016/2017 provided a rare oportunity to assess whether or not an exotic ambrosia beetle, Xylosandrus germanus (Blandford), can resist low winter temperatures in the forests of the Western Carpathians in Slovakia, Central Europe, where it was first recorded in 2010. To answer this, we compared trap captures of this species before and after the respective cold winter. Ethanol-baited traps were first deployed during peak flight activity of X. germanus from May 2016 – June 2016, and then deployed again from May 2017 – June 2017. Traps were deployed in 24 oak (Quercus spp.) dominated forest stands within two habitats consisting of a warm, dry southern area, and a moderately warm, moderately humid central area. Dispering females of X. germanus were recorded in all surveyed stands before and after the cold winter temperatures experience within the region in 2016/2017. Trap captures of X. germanus decreased in the southern area following the excessively low winter temperatures, but remained unchanged it the central area. Our results suggest X. germanus can withstand adverse winter weather in oak forests within altitudes between 171 and 450 m a.s.l. with varying success depending on the area and extremeness of the winter weather. Long-term field studies combined with cold hardiness experiments are needed to determine the causal effects of freezing air temperatures and other factors on the overwintering success of X. germanus in forest ecosystems.