Insect populations in European forests show notable declines, harming a key part of forest ecosystems
In European forests, insect numbers, which account for about 60 percent of the region’s species, have fallen markedly. This trend was reported by TASS and underscores growing concerns about biodiversity in these woodlands.
Insects are among the most diverse animal groups, delivering a range of essential ecosystem services. They help clean ecosystems by removing carrion and diseased trees, serve as crucial prey for mammals and fish, and play a central role in plant pollination. Many insect species are at risk due to habitat loss and rising global temperatures. For example, over the last six years the population of European wasps has dropped by roughly one third, highlighting broad declines in several insect lineages.
Researchers from Europe are increasingly focused on how forest management and natural dynamics influence these numbers. A team led by Michael Staab at the Dresden University of Technology examined insect trends across Germany, sampling 140 locations nationwide. The study tracked changes in more than 1,800 forest-associated species of beetles, together with about 300 herbivorous arthropod species and around 500 invertebrates that eat fungi, are omnivorous, or feed on other invertebrates. The researchers also looked at how forest area, tree and plant diversity, biomass, deadwood volume, and other ecological parameters correlated with insect abundance.
The analysis found a pronounced and sustained decline in forest beetles over the past decade. The downturn affected more than 60 percent of the arthropod species examined, with fungus-eating and carnivorous insects experiencing the strongest declines. The most substantial reductions were observed among insects in forests with a high share of coniferous trees, such as pine and spruce, suggesting that tree composition may influence vulnerability in these communities.
While the researchers do not yet have a definitive explanation for the observed trends, the evidence points toward human activities as a contributing factor. The pattern of declines is notably less pronounced in protected areas, where conservation measures and limited development help shield wildlife from some pressures. These findings align with broader concerns about how land use changes, climate shifts, and forest management practices shape insect diversity and forest health across Europe. The study emphasizes the need for continued monitoring, diversified forestry strategies, and protective initiatives to sustain these crucial components of forest ecosystems. These insights are consistent with global observations that habitat integrity and climate resilience strongly influence insect populations in temperate forests. The work highlights the importance of maintaining a mosaic of forest structures to support a wide range of insect species and the ecological services they provide. See the report for details through the attribution to the research team and the original source of the data. (Source: TASS, Dresden University of Technology)
Additional context from related research suggests that even when overall forest productivity remains stable, shifts in species composition, particularly toward conifer dominance, can alter the habitats that many insects rely on. In practical terms, this means forest managers may need to balance conifer regeneration with mixed-species planting and strategic deadwood retention to help uphold insect diversity and the broader forest food web. As North American forests share many of these ecological dynamics, the findings may offer transferable lessons on how forestry decisions influence insect communities, potential indicators to monitor, and strategies to mitigate declines while supporting timber production and forest resilience.
The conversation around these trends continues in the scientific community, with researchers advocating for integrated approaches that combine field surveys, long-term data, and adaptive management. The goal is to understand how local conditions intersect with global pressures to shape insect populations and to design policies that protect these vital components of forest ecosystems for years to come. The evolving picture suggests that proactive stewardship, rather than reactive measures, will be key to sustaining healthy insect communities and the ecological services they provide. (Source: TASS, study findings from the Dresden University of Technology)