Trait‐mediated responses of caterpillar communities to spongy moth outbreaks and subsequent tebufenozide treatments

作者：Benjamin M. L. Leroy, Dominik Rabl, Marcel Püls, Sophia Hochrein, Soyeon Bae, Jörg Müller, Paul D. N. Hebert, Maria Kuzmina, Evgeny V. Zakharov, Hannes Lemme, Walter A. Hahn, Torben Hilmers, Martin Jacobs, Sebastian Kienlein, Hans Pretzsch, Lea Heidrich, Sebastian Seibold, Nicolas Roth, Sebastian Vogel, Peter Kriegel, Wolfgang W. Weisser · 发表于：Ecological Applications · 年份：2023 · DOI：10.1002/eap.2890 · 被引用次数：14 · 研究领域：Insect and Pesticide Research、Forest Insect Ecology and Management、Insect-Plant Interactions and Control

Outbreaks of the spongy moth Lymantria dispar can have devastating impacts on forest resources and ecosystems. Lepidoptera-specific insecticides, such as Bacillus thuringiensis var. kurstaki (BTK) and tebufenozide, are often deployed to prevent heavy defoliation of the forest canopy. While it has been suggested that using BTK poses less risk to non-target Lepidoptera than leaving an outbreak untreated, in situ testing of this assumption has been impeded by methodological challenges. The trade-offs between insecticide use and outbreaks have yet to be addressed for tebufenozide, which is believed to have stronger side effects than BTK. We investigated the short-term trade-offs between tebufenozide treatments and no-action strategies for the non-target herbivore community in forest canopies. Over 3 years, Lepidoptera and Symphyta larvae were sampled by canopy fogging in 48 oak stands in southeast Germany during and after a spongy moth outbreak. Half of the sites were treated with tebufenozide and changes in canopy cover were monitored. We contrasted the impacts of tebufenozide and defoliator outbreaks on the abundance, diversity, and functional structure of chewing herbivore communities. Tebufenozide treatments strongly reduced Lepidoptera up to 6 weeks after spraying. Populations gradually converged back to control levels after 2 years. Shelter-building species dominated caterpillar assemblages in treated plots in the post-spray weeks, while flight-dimorphic species were slow t...