Urban ecology: comparison of the effectiveness of five traps commonly used to study the biodiversity of flying insects

In this paper, we compare five different types of traps currently used in biodiversity studies to collect flying insects. Our aim is to evaluate the potentials and the limits of these traps in the assessment of insect biodiversity. Hence, we compared the diversity of insects caught by a malaise trap, a yellow pan trap, a blue pan trap, a suction trap and a light trap in six different lo- cations in Brussels. We showed that these traps caught nearly only insects: more than 98.3% of all collected organisms were insects. Only the blue pan trap caught, in higher proportions, other arthropods such as isopods or spiders. The Malaise trap was generally the most effective trap capturing the majority of Homoptera, Heteroptera, Psocoptera, Diptera, Trichoptera and Hy- menoptera. The yellow pan trap was often the second most effective trap particularly for Hy- menoptera, Diptera and Homoptera. Without surprise, the light trap caught nearly all Lepidoptera (Heterocera). Some combinations of two different traps were very effective. However, none of these combinations were the most effective for all families of insects. Moreover, the combination of the two most effective traps (Malaise and yellow pan traps) was not the best combination. We discuss about the effectiveness of traps and the usefulness of their association. Finally, we raise the particular case of urban environment which needs the use of discreet traps.