Changing Insect Catch in Viennese Museums during COVID-19

The COVID-19 pandemic led to significant changes in societies across the globe. In many countries in Europe, national lockdowns during the spring of 2020 meant that museums were closed, and maintenance and housekeeping were at a minimum. We compared the insect monitoring data of 15 museums in and around Vienna between the years 2018 and 2022 to see potential effects of the two lockdowns (spring 2020 and winter 2020/21) on insect populations. In Vienna, these changes altered the presence of pests, most notably an increase in silverfish by late spring (March–May 2020). We also found increased numbers of other pest species (notably Tineola bisselliella and Attagenus sp.), though these changes were seen later (June–October 2020). Thylodrias contractus, although found only in one museum, appeared to show decreased numbers during 2020. Storage areas in some of the museums revealed no significant increase in insect catch during the COVID-19 related closures. Since there are rarely visitors in such spaces, the situation did not change much during the closures. Silverfish are shy insects, but they were able to range more freely during the closures in the mostly darkened rooms. The increase of Tineola bisselliella and Attagenus sp. could be a result of reduced cleaning in the first lockdown. In the second lockdown, no significant changes were found. Human activity from staff was much higher compared to the first closure; a second reason could be the time of year, as in the winter period, it is mainly larvae that are active. Increased insect populations remind us that even when museums are unoccupied, they still need monitoring for possible risks from pests. No damage to the objects from the pests was observed in the museums investigated.