Development of a Poisoned Bait Strategy against the Silverfish Ctenolepisma longicaudata (Escherich, 1905)

SIMPLE SUMMARY: Ctenolepisma longicaudata is emerging as a nuisance pest in private homes in some European countries, and it is considered a serious problem in museums and libraries where it can do damage to objects of historical value. It is a silverfish that may be difficult to eradicate because it utilizes many parts of a building. Heavy use of pesticides is undesirable from a health perspective, and baits with low concentrations of toxins are consequently preferable. To safeguard the indoor environment during management, the present study describes procedures for the efficient control of Ctenolepisma longicaudata with small amounts of bait. This is as efficient, as sprayable pesticides and declines with more than 90% reduction of the pest population can be achieved within 15 to 20 weeks. Successful eradication can be achieved with as little as 0.5 to 1.0 g bait per 100 m(2). ABSTRACT: Pest management strives to be an efficient, yet healthy and environmentally safe control method, and the use of poisoned bait often fulfils these criteria. In the present study, we show that bait with indoxacarb as the active ingredient is highly efficient for controlling Ctenolepisma longicaudata (Escherich, 1905) and two of its relatives, Lepisma saccharina (Linnaeus, 1758) and Ctenolepisma calva (Ritter, 1910). Applying small bait droplets (size ~10 mg) along the walls of several types of buildings, at no more than 0.5 to 1.0 g bait per 100 m(2), was a cost-efficient and safe strategy for the knockdown and eradication of C. longicaudata. During field experiments, the demography changed from an initial mixture of different stages to total dominance of early instars preceding the population collapse. Poisonous bait outcompeted mass-trapping with sticky-traps and conventional insect spray treatment for the efficient control of C. longicaudata in apartments. Different droplet densities (1 vs. 0.5/m(2)) and active ingredients (indoxacarb vs. clothianidin) did not have different effects in field experiments. These results show that poisoned bait is a highly relevant tool for managing C. longicaudata and potentially against other silverfish infestations.