A malaise trap is a large, tent-like structure used for trapping flying insects, particularly Hymenoptera and Diptera. The trap is made of a material such as terylene netting and can be various colours to attract different classes of insects. Insects fly into the tent wall and are funnelled into a collecting vessel attached to the highest point. There are several models of Malaise traps are available like; Malaise traps, ez-Malaise trap, Standard Malaise trap, ez-migration trap, SLAM trap standard, SLAM trap large, SLAM -4headed, Bottom collection for standard SLAM trap.
Placement of the trap is very important; it should be positioned to maximize the number of flying insects that pass through the opening. This is determined by the natural features of the site. One should evaluate topography, vegetation, wind, and water. For example, if a wide corridor in a forest such as a trail is used, the trap should be oriented with its opening to the corridor. Also, places, where vegetation is growing high around the opening, limits the number of flying insects that enter the trap. Other ideal places may be above small streams or on edges of forests.
A well-placed trap in ideal seasonal conditions can catch over 1,000 insects a day. Even in less ideal conditions, such as rain, the trap is still effective.