A new study from southeastern Sweden reveals that different sampling methods detect very different portions of the beetle community in recently burned forests — especially when it comes to red-listed species. Researchers tested five common methods in a post-fire nature reserve (2022–2024): trunk traps, flight-intercept traps, pheromone traps, Malaise traps, and manual searches.
Across all methods, the team collected 2,258 beetles representing 559 species, including 36 red-listed taxa. Flight-intercept traps detected the highest total richness (331 species), while trunk traps were the most effective for threatened species — with 13.4 % of their captured species being red-listed.
Combining flight-intercept and trunk traps could detect nearly 89 % of the beetle fauna, but the study notes that these methods were deployed in different years, meaning temporal variation may influence comparisons. Importantly, 61 % of red-listed species appeared in only one trap type, showing that each method captures a unique part of the community.
The findings highlight that multi-method, temporally consistent sampling is essential for conservation monitoring. Post-fire forests are critical habitats for many specialised beetles, and using only one method risks overlooking species of conservation concern. The authors recommend combining complementary sampling techniques — especially flight-intercept and trunk traps — to improve biodiversity assessments and support evidence-based management of fire-dependent insects.
