Insect Distribution in a Vacant Multi-Level Office Building

SIMPLE SUMMARY: Insects are a problem in domestic and commercial environments where they damage stored products, fabric, and wood. In a vacant building, during its preparation for renovation, a clothes moth (Tineola bisselliella) population grew particularly large on the floors close to ground level. A campaign to trap and identify the insects present suggested that the warm and stable climate allowed the insects to thrive. The basement levels, where sunlight was absent, saw large numbers of silverfish, and the population was dominated by the hitherto little-known ghost silverfish (Ctenolepisma calvum). The larger rooms tended to have more insects. The study suggests that in unoccupied buildings, even where food is limited, insect populations can thrive and expand, so it is important that the interior is occasionally checked for invasive pests. ABSTRACT: The webbing clothes moth (Tineola bisselliella) causes extensive and costly damage to fabrics, furnishings, and museum objects. It is best known from its presence in homes, museums, and historic properties, while infestations in office buildings are not as well understood. Offices typically have more frequent cleaning, fewer quiet habitats, less food availability, and fewer breeding environments for moths, which may explain the lower abundance. Nevertheless, they can be introduced with materials or by employees whose homes have a moth infestation. This study examines the distribution of different insect pests determined from pheromone traps set out in an unoccupied multi-floor office building in Switzerland. Tineola bisselliella dominated the insect catch but was mostly found in the aisles on the lower floors. The larger rooms tended to have a greater insect catch. Carpet beetles (Attagenus smirnovi) and silverfish (Zygentoma) were also found, although in smaller numbers, and often preferred the basement floors. The ghost silverfish (Ctenolepisma calvum) dominated the Zygentoma, even though it has been rare until recently in Switzerland. The study suggests the need for Integrated Pest Management within office buildings. In addition, in unoccupied buildings under renovation, with no obvious sources of food, insect pests still need monitoring.