A great proportion of the Helicoverpa eggs laid onto cotton never hatch. They are either eaten by predators, dislodged from the plant by wind and rain, killed by climatic extremes, or are infertile. If we could accurately predict the level of natural mortality of eggs, growers would be better placed to make control decisions. Utilising the natural mortality of these pests would allow growers the option of sometimes reducing or avoiding insecticidal controls when natural mortality rates are high. A reduction in pesticide application holds many benefits, especially early in the season, when sprays can disrupt the establishment of beneficial insects which are important for the integrated control of both Helicoverpa and mites in cotton. Over the past three seasons, research has been carried out to determine the levels of natural mortality in Helicoverpa eggs, the primary factors causing this mortality and changes in rates of mortality throughout the season. In addition to this, preliminary studies on the establishment and behaviour of newly hatched Helicoverpa larvae on cotton have also been conducted