Markus Melin, Heli Viiri, Olli-Pekka Tikkanen, Riku Elfving, Seppo Neuvonen. (2020). From a rare inhabitant into a potential pest – status of the nun moth in Finland based on pheromone trapping. Silva Fennica vol. 54 no. 1 article id 10262. https://doi.org/10.14214/sf.10262

Keywords: climate change; forest health; forestry; Lymantria monacha; forest damage; insect; range expansion

Highlights: The nun moth is a significant defoliator of coniferous forests in Central-Europe; In Finland, the populations have grown and expanded northwards; Pheromone trapping confirmed the species’ presence throughout central- and southern Finland; The risk of the nun moth becoming a pest for Finland is real as the area offers endless habitats, and climatic conditions are becoming more favourable; This note describes the results from the first nun moth surveys conducted in 2018 and 2019.

Abstract | Full text in HTML | Full text in PDF | Author Info

Forests are affected by climate change in various ways. This includes abiotic factors such as droughts, but also biotic damage by pest insects. There are numerous examples from cases where pest insects have benefitted from longer growing seasons or from warmer summers. Similarly, new pest insects have been able to expand their range due to climatic conditions that have changed from hostile to tolerable. Such seems to be the case with the nun moth (Lymantria monacha), an important defoliator of coniferous trees in Europe. For centuries, the species has had massive outbreaks across Central-Europe, while it has been a rare inhabitant in Northern Europe. Recently, the nun moth population in Finland has not only expanded in range, but also grown more abundant. This research note describes the results from the first years (2018–2019) of a monitoring program that is being conducted with pheromone traps across central and southern Finland. So far, the northernmost individuals were trapped near the 64 N degrees. However, there were more southern locations where no moths were trapped. The species was present in every trapping site below the latitude of 62 N degrees. More importantly, at some sites the abundance of the nun moth suggested that local forest damage may already occur. Given the current climatic scenarios for Fennoscandia, it is likely that the nun moth populations will continue to grow, which is why systematic surveys on their abundance and range expansions will be topical.

Melin, Natural Resources Institute Finland, Yliopistokatu 6b, FI-80100 Joensuu, Finland https://orcid.org/0000-0001-7290-9203 E-mail: markus.melin@luke.fi
Viiri, Natural Resources Institute Finland, Yliopistokatu 6b, FI-80100 Joensuu, Finland; UPM-Kymmene Oyj, UPM Forest, Åkerlundinkatu 11 B, FI-33100 Tampere, Finland E-mail: heli.viiri@upm.com
Tikkanen, University of Eastern Finland, School of Forest Sciences, Yliopistokatu 6, FI-80100 Joensuu, Finland E-mail: olli-pekka.tikkanen@uef.fi
Elfving, Natural Resources Institute Finland, Yliopistokatu 6b, FI-80100 Joensuu, Finland; University of Oulu, Department of Biology, Pentti Kaiteran katu 1, FI-90014 Oulu, Finland E-mail: riku.elfving@gmail.com
Neuvonen, University of Turku, Biodiversity Unit, Kevo Subarctic Research Institute, FI-20014 Turku, Finland E-mail: seppo.neuvonen@utu.fi

Click this link to register to Silva Fennica.

If you are a registered user, log in to save your selected articles for later access.

Contents alert

Your selected articles

Follow @SilvaFennica