Even years after a forest was infested by the pest, the woodpecker population remained high.

Bark beetles have an undeserved bad reputation, wrote the Swiss Federal Institute for Forest, Snow and Landscape Research (WSL) in a press release on the study on Wednesday.

For the study, which was published in the Journal of Animal Ecology, WSL researchers compiled three decades of data on bark beetle infestations and woodpecker populations. The researchers used computer modelling to look for correlations in this data.

After a bark beetle infestation, the number of woodpeckers increased significantly. Of the three woodpecker species analysed, the researchers found the strongest correlations with the three-toed woodpecker.

The scientists expected this, as this woodpecker eats the bark beetles. But even after infested trees had been removed, woodpecker numbers remained high.

According to the researchers, this shows that the birds benefit from the dead wood that the beetles leave behind in large quantities by damaging the trees.

Forestry has already recognised the importance of deadwood for biodiversity and is specifically promoting it, the WSL noted. These efforts are having an effect and there is now more deadwood in Swiss forests than just a few years ago.

Translated from German by DeepL/mga