Sampling, monitoring and forecasting.

A good understanding of sampling theory is essential for research on insect monitoring as well as every other component of insect pest management. This chapter provides both a basic framework of information on sampling, monitoring and forecasting, and an insight into some of the problems confronting scientists working in this field. Case studies are presented, dealing with the effect of trap spacing on trap catch of Erioischia brassicae [ Delia radicum ]; a pheromone trap capture threshold of pink bollworm moths ( Pectinophora gossypiella ) in cotton ( Gossypium hirsutum ); forecasting the time of emergence of sheep blowfly ( Lucilia sericata ); pheromone trap catches of male pink bollworm ( P. gossypiella ) and cotton boll infestation in Barbados; and short-term forecasting of peak population density of the grain aphid ( Sitobion avenae ) on wheat.