Trap design for monitoring moth biodiversity in tropical rainforests

Experimental comparisons were made between samples of moths obtained by Rothamsted tungsten-filament and Robinson mercury-vapour light-traps operating in a lowland dipterocarp forest in Peninsular Malaysia. The Rothamsted trap gave more uniform and consistent samples and performed better in the tropical conditions than the Robinson trap. There were no significant differences between the overall measurement of diversity for the group Geometroidea between the two trap designs although the Robinson trap was much more erratic from night to night. The total catch of non-Geometroidea moths was remarkably similar in the two trap types. The choice of appropriate light-trap designs for biodiversity studies in tropical rainforest is discussed.