Investigating insect catch metrics from a large Austrian museum

Abstract

Insects can damage museum collections. Heritage organisations are increasingly alert to such risk, so have moved towards integrated pest management which sees monitoring as important to conservation strategies. Museum insects are usually monitored using sticky traps, although the records these provide are not always easy to interpret or analyse, so scoring methods, pest occurrence indices and zone systems have been used to use the observations to manage pests. A six-year trapping programme at almost 700 sites (i.e. traps) across six floors of a large museum in Austria provided a total catch of ∼30 000 arthropods. Catch rate (catch per trap) was higher on lower floors although there was a substantial year-to-year variation. In addition to blunder traps, a proportion using pheromones as an attractant were effective at catching T. bisselliella. The pheromone is not attractive to silverfish (Zygentoma) yet the shy insects appear to take cover in the pheromone traps. In contrast Attagenus spp. were caught at equal rates on both pheromone and blunder traps. The study examined what factors influence the catch of insects in traps. The overall catch in a room is proportional to the number of traps set out. Catch increases with the size of the room, but this may arise because the number of traps is also related to room size. More specifically catch seems proportional to square root of room area, suggesting it relates to its perimeter. Infestations are revealed by high catch rate, maximum catches on a set of traps and the proportion of traps that are active in catching insects. The study aims to assess which parameters that might assist in identifying infested locations in museums.