Sampling Adults by Animal Bait Catches and by Animal-Baited Traps

Female mosquitoes are sampled primarily through the use of a suitable bait to attract hungry host-seeking individuals. Human bait catches or landing catches have been used for many years and remain the most useful single method to collect anthropophagic species. Variations on the simple direct bait catch have included enclosing humans or other bait animals in nets, cages or traps which, in theory at least, permit the entrance of mosquitoes but prevent their escape. Although bait catches are not completely free from sampling bias they are usually more so than most other collecting methods that employ an attractant. Direct human landing catches are easily performed and require no complicated or expensive equipment. In some areas, especially in North America, light-traps, with or without carbon dioxide as a supplement, have more or less replaced human and animal baits as a routine sampling method for several species, and the use of light-traps in conjunction with a human volunteer sleeping inside a mosquito net as an alternative to the human landing catch has been investigated in several countries and is discussed further in Chapter 9. However, despite intensive studies on host-seeking behaviour no trapping method has been identified that is sufficiently effective to completely replace the use of human landing catches or animal-baited traps.