Recent Advances in Insect Population Dynamics

Abstract

A field study concerning insect abundance begins with the identification of the insects concerned and with a study of their life cycles and natural history. It then progresses to the taking of census counts from which life tables can be derived, as discussed by Harcourt in the last volume of An­ nual Review of Entomology. We wish first to examine the next two stages in the study, the analysis of life tables and the development of population models, and to discuss their properties; second, to stimulate workers to de­ fine more precisely their reasons for collecting census figures and help them develop a critical understanding of the analytical methods they apply to them, particularly as there are already in the literature examples of the in­ correct use of analytical methods and of their application to unsuitable data. Census routines must be carefully planned to provide information of sufficient accuracy about all the important factors concerned. Provisional analyses should be used early in the study so that serious gaps are revealed; then, census methods can be improved as soon as possible. Many studies in­ clude some routine measurement of weather factors, but if these figures are thought to be important this should be confirmed by physiological studies. If parasites are thought to be important, then a life table must be prepared for them; this will require, as a minimum, separate counts of the parasite's adult and larval popUlation densities in each generation. If predators are thought to be important, their numbers, food requirements and population' regulation also must be investigated.