A study of five methods of sampling Hymenoptera (Insecta) in a tropical rainforest, with special reference to the Parasitica

Abstract

Five methods of sampling Hymenoptera (sweep-netting, Malaise trapping, yellow pan trapping, flight intercept trapping and canopy fogging) in a forest in Sulawesi, Indonesia are investigated. A comparison is made of the relative efficiencies of the methods in terms of sample sizes and numbers of species obtained and the amount of effort involved in obtaining the samples. For most groups of Hymenoptera, sweeping was the most effective single method of sampling. Malaise traps were also very effective in most habitats. At one site, yellow pan traps were found to be exceptionally good for some groups, e.g. Proctotrupidea, Ceraphronoidea, Chalcidoidea and Aculeata. This may have been related to altitude or to the increased visibility of the traps in certain vegetation types. Flight intercept traps were found to be an ineffective means of sampling populations of Hymenoptera although the the use of a contact insecticide might have improved their effectiveness considerably. Knockdown insecticide fogging was found to be an excellent means of sampling the Hymenoptera fauna present in the canopy of a tropical forest.

Keywords :

• Sampling methods
• Hymenoptera
• Tropical forest